adding goio

Makefile

@@ -32,8 +32,17 @@ verify: build
 	hack/verify-gofmt.sh
 	hack/verify-deps.sh
 	hack/verify-bash-completion.sh
+	hack/verify-imports.sh
 .PHONY: verify
 
+imports: ## Organize imports in go files using goio. Example: make imports
+	go run ./vendor/github.com/go-imports-organizer/goio
+.PHONY: imports
+
+verify-imports: ## Run import verifications. Example: make verify-imports
+	hack/verify-imports.sh
+.PHONY: verify-imports
+
 # Build and run unit tests
 #
 # Args:

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/docker/distribution v2.8.1+incompatible
 	github.com/docker/docker v23.0.1+incompatible
 	github.com/docker/go-connections v0.4.0
+	github.com/go-imports-organizer/goio v1.3.1
 	github.com/moby/buildkit v0.11.4
 	github.com/opencontainers/image-spec v1.1.0-rc2
 	github.com/spf13/cobra v1.6.1
@@ -63,11 +64,12 @@ require (
 	github.com/ulikunitz/xz v0.5.11 // indirect
 	github.com/vbatts/tar-split v0.11.2 // indirect
 	go.opencensus.io v0.24.0 // indirect
-	golang.org/x/mod v0.8.0 // indirect
+	golang.org/x/mod v0.9.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
 	golang.org/x/sys v0.6.0 // indirect
 	golang.org/x/text v0.8.0 // indirect
 	golang.org/x/tools v0.6.0 // indirect
 	google.golang.org/protobuf v1.28.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -300,6 +300,8 @@ github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeME
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20191125211704-12ad95a8df72/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
 github.com/go-gl/glfw/v3.3/glfw v0.0.0-20200222043503-6f7a984d4dc4/go.mod h1:tQ2UAYgL5IevRw8kRxooKSPJfGvJ9fJQFa0TUsXzTg8=
+github.com/go-imports-organizer/goio v1.3.1 h1:q72ax5m+TBu4EbbPQGjEIeGOp7SunTT6bEQXQsKWLMc=
+github.com/go-imports-organizer/goio v1.3.1/go.mod h1:2Ca2HiGdeWEra1S9MsLKWdhsf8YNZLm3PtwsFuWM6wM=
 github.com/go-ini/ini v1.25.4/go.mod h1:ByCAeIL28uOIIG0E3PJtZPDL8WnHpFKFOtgjp+3Ies8=
 github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-kit/kit v0.9.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
@@ -789,8 +791,8 @@ golang.org/x/mod v0.1.1-0.20191107180719-034126e5016b/go.mod h1:QqPTAvyqsEbceGzB
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8=
-golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/mod v0.9.0 h1:KENHtAZL2y3NLMYZeHY9DW8HW8V+kQyJsY/V9JlKvCs=
+golang.org/x/mod v0.9.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=

goio.yaml

@@ -0,0 +1,28 @@
+# How the Red Hat OpenShift organization (github.com/openshift) organizes their imports
+# See https://github.com/go-imports-organizer/goio/blob/main/README.md for more information
+excludes:
+  - matchtype: name
+    regexp: ^\.git$
+  - matchtype: name
+    regexp: ^vendor$
+groups:
+  - description: standard
+    matchorder: 3
+    regexp:
+      - ^[a-zA-Z0-9\/]+$
+  - description: kubernetes
+    matchorder: 1
+    regexp:
+      - ^k8s\.io
+  - description: openshift
+    matchorder: 2
+    regexp:
+      - ^github\.com\/openshift
+  - description: other
+    matchorder: 4
+    regexp:
+      - '[a-zA-Z0-9]+\.[a-zA-Z0-9]+/'
+  - description: module
+    matchorder: 0
+    regexp:
+      - "%{module}%"

hack/tools.go

@@ -0,0 +1,9 @@
+//go:build tools
+// +build tools
+
+package hack
+
+// Add tools that scripts depend on here, to ensure they are vendored.
+import (
+	_ "github.com/go-imports-organizer/goio"
+)

hack/verify-imports.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+bad_files=$(go run ./vendor/github.com/go-imports-organizer/goio -l)
+if [[ -n "${bad_files}" ]]; then
+        echo "!!! goio needs to be run on the following files:"
+        echo "${bad_files}"
+        echo "Try running 'make imports'"
+        exit 1
+fi

vendor/github.com/go-imports-organizer/goio/.gitignore

@@ -0,0 +1,3 @@
+goio
+*.pprof
+profile*

vendor/github.com/go-imports-organizer/goio/LICENSE

@@ -0,0 +1,202 @@
+
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+
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vendor/github.com/go-imports-organizer/goio/Makefile

@@ -0,0 +1,48 @@
+#
+# Copyright 2023 Go Imports Organizer Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# 	https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+.DEFAULT_GOAL := help
+
+verify: verify-imports verify-gofmt ## Run verifications. Example: make verify
+.PHONY: verify
+
+verify-imports: ## Run import verifications. Example: make verify-imports
+	scripts/verify-imports.sh
+.PHONY: verify
+
+verify-gofmt: ## Run gofmt verifications. Example: make verify-gofmt
+	scripts/verify-gofmt.sh
+.PHONY: verify
+
+imports: ## Organize imports in go files using goio. Example: make imports
+	go run main.go
+.PHONY: imports
+
+test: ## Run tests. Example: make test
+	go test -test.shuffle on ./pkg/... --cover
+.PHONY: test
+
+build: ## Build the executable. Example: make build
+	@go version
+	go build -mod=readonly -race $(DEBUGFLAGS)
+.PHONY: build
+
+clean: ## Clean up the workspace. Example: make clean
+	rm -rf goio *.pprof profile*
+.PHONY: clean
+
+help: ## Print this help. Example: make help
+	@awk 'BEGIN {FS = ":.*?## "} /^[a-zA-Z_-]+:.*?## / {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}' $(MAKEFILE_LIST)
+.PHONY: help

vendor/github.com/go-imports-organizer/goio/README.md

@@ -0,0 +1,140 @@
+[![Go](https://github.com/go-imports-organizer/goio/actions/workflows/go.yml/badge.svg)](https://github.com/go-imports-organizer/goio/actions/workflows/go.yml) [![Go Reference](https://pkg.go.dev/badge/github.com/go-imports-organizer/goio.svg)](https://pkg.go.dev/github.com/go-imports-organizer/goio)
+# goio
+A customizable imports organizer for the Go programming language
+
+* [Summary](#summary)
+* [Command Line Tool](#command-line-tool)
+* [CI/CD Integration](#ci-cd-integration)
+* [Configuration](#configuration)
+* [Profiling](#profiling)
+
+# <a name='summary'></a>Summary
+`goio` is a fully customizable Go imports organizer. The configuration
+is project based and is stored in a `goio.yaml` file in the root of your
+module's project folder alongside the `go.mod` file. For consistency
+the `goio.yaml` file should be committed to your projects vcs.
+
+
+
+# <a name='command-line-tool'></a>Command Line Tool
+
+## Installation
+```
+  $ go install github.com/go-imports-organizer/goio@latest
+```
+
+## Usage
+```
+Usage of goio:
+  -p value
+    	path to a file or directory to organize, use multiple times for multiple files
+  -l	list files that need to be organized (no changes made)
+  -v	print version and exit
+
+```
+# <a name='ci-cd-configuration'></a>CI/CD Configuration
+
+## Example scripts/tools.go file
+This file will ensure that the `github.com/go-imports-organizer/goio` repo is vendored into your project.
+```
+//go:build tools
+// +build tools
+
+package scripts
+
+// Add tools that scripts depend on here, to ensure they are vendored.
+import (
+	_ "github.com/go-imports-organizer/goio"
+)
+
+```
+
+## Example scripts/verify-imports.sh script
+This file will check if there are any go files that need to be formatted. If there are, it will print a list of them, and exit with status one (1), otherwise it will exit with status zero (0). Make sure that you make the file executable with `chmod +x scripts/verify-imports.sh`.
+```
+#!/bin/bash
+
+bad_files=$(go run ./vendor/github.com/go-imports-organizer/goio -l)
+if [[ -n "${bad_files}" ]]; then
+        echo "!!! goio needs to be run on the following files:"
+        echo "${bad_files}"
+        echo "Try running 'make imports'"
+        exit 1
+fi
+```
+
+## Example Makefile sections
+```
+imports: ## Organize imports in go files using goio. Example: make imports
+	go run ./vendor/github.com/go-imports-organizer/goio
+.PHONY: imports
+
+verify-imports: ## Run import verifications. Example: make verify-imports
+	hack/verify-imports.sh
+.PHONY: verify-imports
+```
+
+# <a name='configuration-file'></a>Configuration File
+The `goio.yaml` configuration file is a well formatted yaml file.
+
+## Excludes
+An array of Exclude definitions.
+
+Each Exclude definition is a rule that tells `goio` which files and folders to ignore while looking for Go files that it should organize the imports of. The default configuration file ignores the `.git` directory and the `vendor` directory. The more files and folders that you can ignore at this stage the faster `goio` will run.
+
+### RegExp
+A string, valid values are any valid Go regular expression.
+
+A well formatted Regular Expression that is used to match against. Be as specific as possible.
+
+### MatchType
+A string, valid values are `[name, path]`.
+
+Lets `goio` know whether to match agains the files `name` or the files `path` relative to the modules root directory _(where the go.mod file is located)_.
+
+## Groups
+An array of Group definitions
+
+Each group definition is a rule that tells `goio` how you would like the `imports` in your Go files organized. Each definition represents a block of import statements, describing how to identify the items that it should contain. Group blocks are displayed in **the order that they appear in the array**.
+
+### Description
+A string, valid values are any valid string value
+
+A friendly name to identify the definition by instead of trying to decipher the regular expression each time to remember what it does.
+
+### RegExp
+An array of strings, valid values are any valid Go regular expression.
+
+A well formatted Regular Expression that is used to match against. Be as specific as possible.
+
+**NOTE:**
+
+There is one keyword that is available for the RegExp value that is a special keyword, it is `%{module}%`. This keyword automatically creates a regular expression that matches the current module name as defined by the go.mod file. To ensure that it captures the correct imports you should always set the `MatchOrder` to `0` for this definition.
+
+### MatchOrder
+An integer, valid values are -n...n
+
+Tells `goio` which order the definitions should be matched against in. Lower numbers are first, higher numbers are last.
+
+It is important to ensure the correct `matchorder` is used, expecially if any of your `regexp` have any kind of overlap, such as having a module name of `github.com/example/mymodule` and a group definition for `github.com/example`. You would want to make sure that your `module` definition was matched first or those imports would get rolled into the `github.com/example` one because it is less specific.
+
+**NOTE**
+The recommended Match Order to avoid the above scenario is:
+ - module *(should always be first)*
+ - custom groups *(ordered most specific to least specific)*
+ - standard *(should be second to last)*
+ - other *(should be last)*
+
+# <a name='profiling'></a>Profiling
+Profiling via the `pprof` tools is already configured within the application and can be enabled using the following methods.
+## CPU Profiling
+You can enable CPU profiling by setting the `CPUPROFILE` environment variable to the name of the file that the profiling information should be written to.
+```
+  $ CPUPROFILE=cpu.pprof goio
+```
+
+## Memory Profiling
+You can enable MEMORY profiling by setting the `MEMPROFILE` environment variable to the name of the file that the profiling information should be written to.
+```
+  $ MEMPROFILE=mem.pprof goio
+```

vendor/github.com/go-imports-organizer/goio/go.work

@@ -0,0 +1,3 @@
+go 1.19
+
+use .

vendor/github.com/go-imports-organizer/goio/goio.yaml

@@ -0,0 +1,20 @@
+excludes:
+  - matchtype: name
+    regexp: ^\.git$
+  - matchtype: name
+    regexp: ^vendor$
+  - matchtype: name
+    regexp: ^testdata$
+groups:
+  - description: standard
+    matchorder: 1
+    regexp:
+      - ^[a-zA-Z0-9\/]+$
+  - description: other
+    matchorder: 2
+    regexp:
+      - '[a-zA-Z0-9]+\.[a-zA-Z0-9]+/'
+  - description: module
+    matchorder: 0
+    regexp:
+      - "%{module}%"

vendor/github.com/go-imports-organizer/goio/main.go

@@ -0,0 +1,186 @@
+/*
+Copyright 2023 Go Imports Organizer Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"runtime/pprof"
+	"strings"
+	"sync"
+
+	v1alpha1 "github.com/go-imports-organizer/goio/pkg/api/v1alpha1"
+	"github.com/go-imports-organizer/goio/pkg/config"
+	"github.com/go-imports-organizer/goio/pkg/excludes"
+	"github.com/go-imports-organizer/goio/pkg/groups"
+	"github.com/go-imports-organizer/goio/pkg/imports"
+	"github.com/go-imports-organizer/goio/pkg/module"
+	"github.com/go-imports-organizer/goio/pkg/version"
+)
+
+var (
+	wg       sync.WaitGroup
+	files    = make(chan string)
+	pathList v1alpha1.PathListFlags
+)
+
+func main() {
+	listOnly := flag.Bool("l", false, "only list files that need to be organized (no changes made)")
+	flag.Var(&pathList, "p", "specify individual paths to organize, use multiple times for multiple paths. defaults to entire module directory")
+	versionOnly := flag.Bool("v", false, "print version and exit")
+	flag.Parse()
+
+	// set CPUPROFILE=<filename> to create a <filename>.pprof cpu profile file
+	if len(os.Getenv("CPUPROFILE")) != 0 {
+		fmt.Fprintf(os.Stdout, "Logging CPU profiling information to %s\n", os.Getenv(("CPUPROFILE")))
+		f, err := os.Create(os.Getenv("CPUPROFILE"))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s", err.Error())
+			os.Exit(1)
+		}
+		pprof.StartCPUProfile(f)
+		defer pprof.StopCPUProfile()
+	}
+
+	if *versionOnly {
+		fmt.Fprintf(os.Stdout, "%s\n", version.Get())
+		os.Exit(0)
+	}
+
+	currentDir, err := os.Getwd()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "unable to get current working directory: %s\n", err.Error())
+		os.Exit(1)
+	}
+
+	// Find the Go module name and path
+	goModuleName, goModulePath, err := module.FindGoModuleNameAndPath(currentDir)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error occurred finding module path: %s\n", err.Error())
+		os.Exit(1)
+	}
+
+	// Load the configuration from the goio.yaml file
+	conf, err := config.Load("goio.yaml")
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error occurred loading configuration file: %s\n", err.Error())
+		os.Exit(1)
+	}
+
+	// Build the Regular Expressions for excluding files/folders
+	excludeByNameRegExp, excludeByPathRegExp := excludes.Build(conf.Excludes)
+
+	// Build the Regular Expressions and DisplayOrder for the group definitions
+	groupRegExpMatchers, displayOrder := groups.Build(conf.Groups, goModuleName)
+
+	wg.Add(1)
+	// Start up the Format worker so that it is ready when we start queuing up files
+	go imports.Format(&files, &wg, groupRegExpMatchers, displayOrder, listOnly)
+
+	// Set the basePath for use later
+	basePath := goModulePath + "/"
+
+	// Change our working directory to the goModulePath
+	err = os.Chdir(goModulePath)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "unable to change directory to %q: %s\n", goModulePath, err.Error())
+		os.Exit(1)
+	}
+
+	// Pre-optization so that we can skip the Name or Path matches if they are empty
+	excludeByNameRegExpLenOk := len(excludeByNameRegExp.String()) != 0
+	excludeByPathRegExpLenOk := len(excludeByPathRegExp.String()) != 0
+
+	// If no paths are supplied via the -p flag use the current directory
+	if len(pathList) == 0 {
+		pathList = append(pathList, goModulePath)
+	}
+
+	for _, path := range pathList {
+		f, err := os.Stat(path)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "unable to stat %q: %s\n", path, err.Error())
+			continue
+		}
+
+		// If the path is a Go file
+		if strings.HasSuffix(path, ".go") {
+			// If the files name or path matches an exclude Regular Expression, skip it
+			if (excludeByNameRegExpLenOk && excludeByNameRegExp.MatchString(f.Name())) || (excludeByPathRegExpLenOk && excludeByPathRegExp.MatchString(path)) {
+				continue
+			}
+			// If the file is not excluded by name or path, queue it for organizing
+			files <- path
+
+		} else if f.IsDir() {
+			// If the path is a directory
+			if err = filepath.Walk(path, func(path string, f os.FileInfo, err error) error {
+				if err != nil {
+					return err
+				}
+				name := f.Name()
+				isDir := f.IsDir()
+				isGoFile := strings.HasSuffix(name, ".go")
+				relativePath := strings.Replace(path, basePath, "", 1)
+				// If the object is not a directory and not a Go file, skip it
+				if isDir || isGoFile {
+					// If the objects name or path matches an exclude Regular Expression, skip it
+					if (excludeByNameRegExpLenOk && excludeByNameRegExp.MatchString(name)) || (excludeByPathRegExpLenOk && excludeByPathRegExp.MatchString(relativePath)) {
+						// If the object is a Directory, skip the entire thing
+						if isDir {
+							return filepath.SkipDir
+						}
+						return nil
+					}
+
+					// If the object is a Go file and is not excluded, queue it for organizing
+					if isGoFile {
+						files <- relativePath
+					}
+				}
+				return nil
+			}); err != nil {
+				fmt.Fprintf(os.Stderr, "unable to complete walking file tree: %s\n", err.Error())
+			}
+		}
+
+	}
+
+	// Close the files channel since we are done queuing up files to format
+	close(files)
+
+	// Wait for all files to be processed
+	wg.Wait()
+
+	// set MEMPROFILE=<filename> to create a <filename>.pprof memory profile file
+	if len(os.Getenv("MEMPROFILE")) != 0 {
+		fmt.Fprintf(os.Stdout, "Logging MEMORY profiling information to %s\n", os.Getenv(("MEMPROFILE")))
+		f, err := os.Create(os.Getenv("MEMPROFILE"))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s", err.Error())
+			os.Exit(1)
+		}
+		defer f.Close()
+		runtime.GC()
+		if err := pprof.WriteHeapProfile(f); err != nil {
+			fmt.Fprintf(os.Stderr, "could not write memory profile: %s", err.Error())
+			os.Exit(1)
+		}
+	}
+}

vendor/github.com/go-imports-organizer/goio/pkg/api/v1alpha1/types.go

@@ -0,0 +1,73 @@
+/*
+Copyright 2023 Go Imports Organizer Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package v1alpha1
+
+import (
+	"regexp"
+	"strings"
+)
+
+// RegExpMatcher
+type RegExpMatcher struct {
+	Bucket string         `yaml:"bucket"`
+	RegExp *regexp.Regexp `yaml:"regexp"`
+}
+
+const (
+	// ExcludeMatchTypeName tells an Exclude to match against the file or folder name
+	ExcludeMatchTypeName string = "name"
+	// ExcludeMatchTypeRelativePath tells an Exclude to match against the file or folder path
+	ExcludeMatchTypeRelativePath string = "path"
+)
+
+// Exclude defines a file or folder that should be excluded from being organized
+type Exclude struct {
+	// MatchType defines whether the file name or file path should be matched against
+	MatchType string `yaml:"matchtype"`
+	// RegExp is the Regular Expression that is used to match against
+	RegExp string `yaml:"regexp"`
+}
+
+// Group defines a block of imports
+type Group struct {
+	// MatchOrder is the order is which the Regular Expression will be matched
+	// against an import to determine its group
+	MatchOrder int `yaml:"matchorder"`
+	// Description is a friendly name for the group
+	Description string `yaml:"description"`
+	// RegExp is the Regular Expression that is used to match against
+	RegExp []string `yaml:"regexp"`
+}
+
+// Config is the configuration for the Go Imports Organizer
+type Config struct {
+	// Excludes is a slice of Exclude objects
+	Excludes []Exclude `yaml:"excludes"`
+	// Groups is a slice of Group objects
+	Groups []Group `yaml:"groups"`
+}
+
+// PathListFlags is a type that can store Path objects that are supplied via the -p flag
+type PathListFlags []string
+
+func (i *PathListFlags) String() string {
+	return strings.Join(*i, ",")
+}
+
+func (i *PathListFlags) Set(value string) error {
+	*i = append(*i, value)
+	return nil
+}

vendor/github.com/go-imports-organizer/goio/pkg/config/config.go

@@ -0,0 +1,26 @@
+package config
+
+import (
+	"fmt"
+	"os"
+
+	"gopkg.in/yaml.v3"
+
+	v1alpha1 "github.com/go-imports-organizer/goio/pkg/api/v1alpha1"
+)
+
+// Load loads the configuration from a yaml file
+func Load(file string) (v1alpha1.Config, error) {
+	var configFile []byte
+	var err error
+	if configFile, err = os.ReadFile(file); err != nil {
+		return v1alpha1.Config{}, fmt.Errorf("unable to read configuration file %s: %s", file, err.Error())
+	}
+
+	var config v1alpha1.Config
+	if err = yaml.Unmarshal(configFile, &config); err != nil {
+		return v1alpha1.Config{}, fmt.Errorf("unable to unmarshal file %s: %s", file, err.Error())
+	}
+
+	return config, nil
+}

vendor/github.com/go-imports-organizer/goio/pkg/excludes/excludes.go

@@ -0,0 +1,25 @@
+package excludes
+
+import (
+	"regexp"
+	"strings"
+
+	v1alpha1 "github.com/go-imports-organizer/goio/pkg/api/v1alpha1"
+)
+
+// Build assembles the Regular Expressions that are used to exclude files and folders
+// based on their name or path
+func Build(excludes []v1alpha1.Exclude) (*regexp.Regexp, *regexp.Regexp) {
+	var excludeByPath []string
+	var excludeByName []string
+
+	for _, exclude := range excludes {
+		switch exclude.MatchType {
+		case v1alpha1.ExcludeMatchTypeName:
+			excludeByName = append(excludeByName, exclude.RegExp)
+		case v1alpha1.ExcludeMatchTypeRelativePath:
+			excludeByPath = append(excludeByPath, exclude.RegExp)
+		}
+	}
+	return regexp.MustCompile(strings.Join(excludeByName, "|")), regexp.MustCompile(strings.Join(excludeByPath, "|"))
+}

vendor/github.com/go-imports-organizer/goio/pkg/groups/groups.go

@@ -0,0 +1,35 @@
+package groups
+
+import (
+	"fmt"
+	"regexp"
+	"sort"
+	"strings"
+
+	v1alpha1 "github.com/go-imports-organizer/goio/pkg/api/v1alpha1"
+	"github.com/go-imports-organizer/goio/pkg/sorter"
+)
+
+// Build asembles the RegExpMatchers that are used to group imports and the
+// array that defines the display order for the groups in the import block
+func Build(groups []v1alpha1.Group, goModuleName string) ([]v1alpha1.RegExpMatcher, []string) {
+	groupRegExpMatchers := []v1alpha1.RegExpMatcher{}
+	displayOrder := []string{}
+
+	for _, group := range groups {
+		displayOrder = append(displayOrder, group.Description)
+	}
+
+	sort.Sort(sorter.SortGroupsByMatchOrder(groups))
+
+	for i := range groups {
+		r := strings.Join(groups[i].RegExp, "|")
+		r = strings.Replace(r, `%{module}%`, fmt.Sprintf("^%s", strings.ReplaceAll(strings.ReplaceAll(goModuleName, `.`, `\.`), `/`, `\/`)), -1)
+		groupRegExpMatchers = append(groupRegExpMatchers, v1alpha1.RegExpMatcher{
+			Bucket: groups[i].Description,
+			RegExp: regexp.MustCompile(r),
+		},
+		)
+	}
+	return groupRegExpMatchers, displayOrder
+}

vendor/github.com/go-imports-organizer/goio/pkg/imports/imports.go

@@ -0,0 +1,222 @@
+/*
+Copyright 2023 Go Imports Organizer Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package imports
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"go/ast"
+	"go/format"
+	"go/parser"
+	"go/printer"
+	"go/scanner"
+	"go/token"
+	"io"
+	"os"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+
+	v1alpha1 "github.com/go-imports-organizer/goio/pkg/api/v1alpha1"
+	"github.com/go-imports-organizer/goio/pkg/sorter"
+)
+
+// AddSpaces adds empty lines (spaces) between the groups of imports
+// borrowed from https://github.com/golang/tools/blob/71482053b885ea3938876d1306ad8a1e4037f367/internal/imports/imports.go#L380
+func AddSpaces(r io.Reader, breaks []string) ([]byte, error) {
+	var out bytes.Buffer
+	in := bufio.NewReader(r)
+	inImports := false
+	done := false
+	for {
+		s, err := in.ReadString('\n')
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+
+		if !inImports && !done && strings.HasPrefix(s, "import") {
+			inImports = true
+		}
+		if inImports && (strings.HasPrefix(s, "var") ||
+			strings.HasPrefix(s, "func") ||
+			strings.HasPrefix(s, "const") ||
+			strings.HasPrefix(s, "type")) {
+			done = true
+			inImports = false
+		}
+		if inImports && len(breaks) > 0 {
+			if m := regexp.MustCompile(`^\s+(?:[\w\.]+\s+)?"(.+)"`).FindStringSubmatch(s); m != nil {
+				if m[1] == breaks[0] {
+					out.WriteByte('\n')
+					breaks = breaks[1:]
+				}
+			}
+		}
+		fmt.Fprint(&out, s)
+	}
+	return out.Bytes(), nil
+}
+
+// PopulateGroups assembles the data structure that is used to hold the groups
+// of ImportSpecs as they are organized
+func PopulateGroups(importGroups map[string][]ast.ImportSpec, regExpMatchers []v1alpha1.RegExpMatcher, imports []*ast.ImportSpec) error {
+	for _, i := range imports {
+		if len(i.Path.Value) == 0 {
+			continue
+		}
+		found := false
+		unquotedPath, err := strconv.Unquote(i.Path.Value)
+		if err != nil {
+			return fmt.Errorf("unable to unquote %s", i.Path.Value)
+		}
+		for _, r := range regExpMatchers {
+			if r.RegExp.MatchString(unquotedPath) {
+				if _, ok := importGroups[r.Bucket]; !ok {
+					importGroups[r.Bucket] = []ast.ImportSpec{}
+				}
+				importGroups[r.Bucket] = append(importGroups[r.Bucket], *i)
+				found = true
+				break
+			}
+		}
+		if !found {
+			importGroups["other"] = append(importGroups["other"], *i)
+		}
+	}
+	return nil
+}
+
+// InsertGroup places the groups of ImportSpecs into their correct order in the
+// File according to the display order
+func InsertGroups(f *ast.File, importGroups map[string][]ast.ImportSpec, displayOrder []string) ([]string, error) {
+	var breaks []string
+	for _, decl := range f.Decls {
+		gen, ok := decl.(*ast.GenDecl)
+		if ok && gen.Tok == token.IMPORT {
+			gen.Specs = []ast.Spec{}
+			for _, group := range displayOrder {
+				sort.Sort(sorter.SortImportsByPathValue(importGroups[group]))
+				for n := range importGroups[group] {
+					importGroups[group][n].EndPos = 0
+					importGroups[group][n].Path.ValuePos = 0
+					if importGroups[group][n].Name != nil {
+						importGroups[group][n].Name.NamePos = 0
+					}
+					gen.Specs = append(gen.Specs, &importGroups[group][n])
+					if n == 0 && group != displayOrder[0] {
+						newstr, err := strconv.Unquote(importGroups[group][n].Path.Value)
+						if err != nil {
+							return nil, err
+						}
+						breaks = append(breaks, newstr)
+					}
+				}
+			}
+		}
+	}
+	return breaks, nil
+}
+
+// Format processes files as they are added to the queue and organizes the imports
+func Format(files *chan string, wg *sync.WaitGroup, groupRegExpMatchers []v1alpha1.RegExpMatcher, displayOrder []string, listOnly *bool) {
+	defer wg.Done()
+	for path := range *files {
+		if len(path) == 0 {
+			continue
+		}
+
+		info, err := os.Stat(path)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "unable to stat %q", err.Error())
+			continue
+		}
+		oldModTime := info.ModTime()
+
+		fs := token.NewFileSet()
+		f, err := parser.ParseFile(fs, path, nil, parser.ParseComments)
+		if err != nil {
+			var scannerErrorList scanner.ErrorList
+			if errors.As(err, &scannerErrorList) {
+				for _, err := range scannerErrorList {
+					fmt.Fprintf(os.Stderr, "%s", err)
+				}
+			} else {
+				fmt.Fprintf(os.Stderr, "%s", err.Error())
+			}
+		}
+
+		var importGroups = make(map[string][]ast.ImportSpec)
+		if err := PopulateGroups(importGroups, groupRegExpMatchers, f.Imports); err != nil {
+			fmt.Fprintf(os.Stderr, "unable to populate import groups for %q: %s", path, err)
+			continue
+		}
+
+		breaks, err := InsertGroups(f, importGroups, displayOrder)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "unable to update groups at %q: %s", path, err.Error())
+			continue
+		}
+
+		printerMode := printer.TabIndent
+
+		printConfig := &printer.Config{Mode: printerMode, Tabwidth: 4}
+
+		var buf bytes.Buffer
+		if err = printConfig.Fprint(&buf, fs, f); err != nil {
+			fmt.Fprintf(os.Stderr, "unable to load bytes into buffer %q, %s", path, err.Error())
+			continue
+		}
+		out, err := AddSpaces(bytes.NewReader(buf.Bytes()), breaks)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "unable to add spaces to %q, %s", path, err.Error())
+			continue
+		}
+		out, err = format.Source(out)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "unable to format source %q, %s", path, err.Error())
+		}
+
+		if *listOnly {
+			oldFile, err := os.ReadFile(path)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "unable to read file %q: %s", path, err.Error())
+				continue
+			}
+			if !bytes.Equal(oldFile, out) {
+				fmt.Fprintf(os.Stdout, "%s is not organized \n", path)
+			}
+		}
+
+		info, err = os.Stat(path)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "unable to stat %q: %s", path, err.Error())
+			continue
+		}
+		if !info.ModTime().Equal(oldModTime) {
+			fmt.Fprintf(os.Stderr, "%s was modified while formatting, cowardly refusing to overwrite", path)
+			continue
+		}
+		if err = os.WriteFile(path, out, info.Mode()); err != nil {
+			fmt.Fprintf(os.Stderr, "unable to write to path %q, %s", path, err.Error())
+		}
+	}
+}

vendor/github.com/go-imports-organizer/goio/pkg/module/find.go

@@ -0,0 +1,51 @@
+/*
+Copyright 2023 Go Imports Organizer Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package module
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"golang.org/x/mod/modfile"
+)
+
+// FindGoModuleNameAndPath finds the current Go modules name (via the go.mod file)
+// and path (location of the go.mod file on the filesystem)
+func FindGoModuleNameAndPath(path string) (string, string, error) {
+	for path != "." {
+		if _, err := os.Stat(path); err != nil {
+			if os.IsNotExist(err) {
+				return "", "", fmt.Errorf("%s does not exist: %s", path, err.Error())
+			}
+		}
+		if _, err := os.Stat(fmt.Sprintf("%s/go.mod", path)); err != nil {
+			path = filepath.Dir(path)
+			continue
+		}
+		break
+	}
+
+	f, err := os.ReadFile(fmt.Sprintf("%s/go.mod", path))
+	if err != nil {
+		return "", "", fmt.Errorf("unable to open go.mod file for reading: %v", err)
+	}
+	module := modfile.ModulePath(f)
+	if len(module) == 0 {
+		return "", "", fmt.Errorf("unable to determine module")
+	}
+	return module, path, nil
+}

vendor/github.com/go-imports-organizer/goio/pkg/sorter/sorter.go

@@ -0,0 +1,36 @@
+/*
+Copyright 2023 Go Imports Organizer Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package sorter
+
+import (
+	"go/ast"
+
+	v1alpha1 "github.com/go-imports-organizer/goio/pkg/api/v1alpha1"
+)
+
+// SortImportsByPathValue sorts a slice of ImportSpecs using their Path.Value
+type SortImportsByPathValue []ast.ImportSpec
+
+func (a SortImportsByPathValue) Len() int           { return len(a) }
+func (a SortImportsByPathValue) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a SortImportsByPathValue) Less(i, j int) bool { return a[i].Path.Value < a[j].Path.Value }
+
+// SortGroupsByMatchOrder sorts a slice of Group objects using their MatchOrder
+type SortGroupsByMatchOrder []v1alpha1.Group
+
+func (a SortGroupsByMatchOrder) Len() int           { return len(a) }
+func (a SortGroupsByMatchOrder) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a SortGroupsByMatchOrder) Less(i, j int) bool { return a[i].MatchOrder < a[j].MatchOrder }

vendor/github.com/go-imports-organizer/goio/pkg/version/version.go

@@ -0,0 +1,15 @@
+package version
+
+import (
+	"runtime/debug"
+)
+
+var Version string
+
+// Get returns the applications Version based on its build information
+func Get() string {
+	if info, ok := debug.ReadBuildInfo(); ok {
+		return info.Main.Version
+	}
+	return "unknown"
+}

vendor/golang.org/x/mod/internal/lazyregexp/lazyre.go

@@ -0,0 +1,78 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package lazyregexp is a thin wrapper over regexp, allowing the use of global
+// regexp variables without forcing them to be compiled at init.
+package lazyregexp
+
+import (
+	"os"
+	"regexp"
+	"strings"
+	"sync"
+)
+
+// Regexp is a wrapper around regexp.Regexp, where the underlying regexp will be
+// compiled the first time it is needed.
+type Regexp struct {
+	str  string
+	once sync.Once
+	rx   *regexp.Regexp
+}
+
+func (r *Regexp) re() *regexp.Regexp {
+	r.once.Do(r.build)
+	return r.rx
+}
+
+func (r *Regexp) build() {
+	r.rx = regexp.MustCompile(r.str)
+	r.str = ""
+}
+
+func (r *Regexp) FindSubmatch(s []byte) [][]byte {
+	return r.re().FindSubmatch(s)
+}
+
+func (r *Regexp) FindStringSubmatch(s string) []string {
+	return r.re().FindStringSubmatch(s)
+}
+
+func (r *Regexp) FindStringSubmatchIndex(s string) []int {
+	return r.re().FindStringSubmatchIndex(s)
+}
+
+func (r *Regexp) ReplaceAllString(src, repl string) string {
+	return r.re().ReplaceAllString(src, repl)
+}
+
+func (r *Regexp) FindString(s string) string {
+	return r.re().FindString(s)
+}
+
+func (r *Regexp) FindAllString(s string, n int) []string {
+	return r.re().FindAllString(s, n)
+}
+
+func (r *Regexp) MatchString(s string) bool {
+	return r.re().MatchString(s)
+}
+
+func (r *Regexp) SubexpNames() []string {
+	return r.re().SubexpNames()
+}
+
+var inTest = len(os.Args) > 0 && strings.HasSuffix(strings.TrimSuffix(os.Args[0], ".exe"), ".test")
+
+// New creates a new lazy regexp, delaying the compiling work until it is first
+// needed. If the code is being run as part of tests, the regexp compiling will
+// happen immediately.
+func New(str string) *Regexp {
+	lr := &Regexp{str: str}
+	if inTest {
+		// In tests, always compile the regexps early.
+		lr.re()
+	}
+	return lr
+}

vendor/golang.org/x/mod/modfile/print.go

@@ -0,0 +1,174 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Module file printer.
+
+package modfile
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+)
+
+// Format returns a go.mod file as a byte slice, formatted in standard style.
+func Format(f *FileSyntax) []byte {
+	pr := &printer{}
+	pr.file(f)
+	return pr.Bytes()
+}
+
+// A printer collects the state during printing of a file or expression.
+type printer struct {
+	bytes.Buffer           // output buffer
+	comment      []Comment // pending end-of-line comments
+	margin       int       // left margin (indent), a number of tabs
+}
+
+// printf prints to the buffer.
+func (p *printer) printf(format string, args ...interface{}) {
+	fmt.Fprintf(p, format, args...)
+}
+
+// indent returns the position on the current line, in bytes, 0-indexed.
+func (p *printer) indent() int {
+	b := p.Bytes()
+	n := 0
+	for n < len(b) && b[len(b)-1-n] != '\n' {
+		n++
+	}
+	return n
+}
+
+// newline ends the current line, flushing end-of-line comments.
+func (p *printer) newline() {
+	if len(p.comment) > 0 {
+		p.printf(" ")
+		for i, com := range p.comment {
+			if i > 0 {
+				p.trim()
+				p.printf("\n")
+				for i := 0; i < p.margin; i++ {
+					p.printf("\t")
+				}
+			}
+			p.printf("%s", strings.TrimSpace(com.Token))
+		}
+		p.comment = p.comment[:0]
+	}
+
+	p.trim()
+	p.printf("\n")
+	for i := 0; i < p.margin; i++ {
+		p.printf("\t")
+	}
+}
+
+// trim removes trailing spaces and tabs from the current line.
+func (p *printer) trim() {
+	// Remove trailing spaces and tabs from line we're about to end.
+	b := p.Bytes()
+	n := len(b)
+	for n > 0 && (b[n-1] == '\t' || b[n-1] == ' ') {
+		n--
+	}
+	p.Truncate(n)
+}
+
+// file formats the given file into the print buffer.
+func (p *printer) file(f *FileSyntax) {
+	for _, com := range f.Before {
+		p.printf("%s", strings.TrimSpace(com.Token))
+		p.newline()
+	}
+
+	for i, stmt := range f.Stmt {
+		switch x := stmt.(type) {
+		case *CommentBlock:
+			// comments already handled
+			p.expr(x)
+
+		default:
+			p.expr(x)
+			p.newline()
+		}
+
+		for _, com := range stmt.Comment().After {
+			p.printf("%s", strings.TrimSpace(com.Token))
+			p.newline()
+		}
+
+		if i+1 < len(f.Stmt) {
+			p.newline()
+		}
+	}
+}
+
+func (p *printer) expr(x Expr) {
+	// Emit line-comments preceding this expression.
+	if before := x.Comment().Before; len(before) > 0 {
+		// Want to print a line comment.
+		// Line comments must be at the current margin.
+		p.trim()
+		if p.indent() > 0 {
+			// There's other text on the line. Start a new line.
+			p.printf("\n")
+		}
+		// Re-indent to margin.
+		for i := 0; i < p.margin; i++ {
+			p.printf("\t")
+		}
+		for _, com := range before {
+			p.printf("%s", strings.TrimSpace(com.Token))
+			p.newline()
+		}
+	}
+
+	switch x := x.(type) {
+	default:
+		panic(fmt.Errorf("printer: unexpected type %T", x))
+
+	case *CommentBlock:
+		// done
+
+	case *LParen:
+		p.printf("(")
+	case *RParen:
+		p.printf(")")
+
+	case *Line:
+		p.tokens(x.Token)
+
+	case *LineBlock:
+		p.tokens(x.Token)
+		p.printf(" ")
+		p.expr(&x.LParen)
+		p.margin++
+		for _, l := range x.Line {
+			p.newline()
+			p.expr(l)
+		}
+		p.margin--
+		p.newline()
+		p.expr(&x.RParen)
+	}
+
+	// Queue end-of-line comments for printing when we
+	// reach the end of the line.
+	p.comment = append(p.comment, x.Comment().Suffix...)
+}
+
+func (p *printer) tokens(tokens []string) {
+	sep := ""
+	for _, t := range tokens {
+		if t == "," || t == ")" || t == "]" || t == "}" {
+			sep = ""
+		}
+		p.printf("%s%s", sep, t)
+		sep = " "
+		if t == "(" || t == "[" || t == "{" {
+			sep = ""
+		}
+	}
+}

vendor/golang.org/x/mod/modfile/read.go

@@ -0,0 +1,958 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package modfile
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// A Position describes an arbitrary source position in a file, including the
+// file, line, column, and byte offset.
+type Position struct {
+	Line     int // line in input (starting at 1)
+	LineRune int // rune in line (starting at 1)
+	Byte     int // byte in input (starting at 0)
+}
+
+// add returns the position at the end of s, assuming it starts at p.
+func (p Position) add(s string) Position {
+	p.Byte += len(s)
+	if n := strings.Count(s, "\n"); n > 0 {
+		p.Line += n
+		s = s[strings.LastIndex(s, "\n")+1:]
+		p.LineRune = 1
+	}
+	p.LineRune += utf8.RuneCountInString(s)
+	return p
+}
+
+// An Expr represents an input element.
+type Expr interface {
+	// Span returns the start and end position of the expression,
+	// excluding leading or trailing comments.
+	Span() (start, end Position)
+
+	// Comment returns the comments attached to the expression.
+	// This method would normally be named 'Comments' but that
+	// would interfere with embedding a type of the same name.
+	Comment() *Comments
+}
+
+// A Comment represents a single // comment.
+type Comment struct {
+	Start  Position
+	Token  string // without trailing newline
+	Suffix bool   // an end of line (not whole line) comment
+}
+
+// Comments collects the comments associated with an expression.
+type Comments struct {
+	Before []Comment // whole-line comments before this expression
+	Suffix []Comment // end-of-line comments after this expression
+
+	// For top-level expressions only, After lists whole-line
+	// comments following the expression.
+	After []Comment
+}
+
+// Comment returns the receiver. This isn't useful by itself, but
+// a Comments struct is embedded into all the expression
+// implementation types, and this gives each of those a Comment
+// method to satisfy the Expr interface.
+func (c *Comments) Comment() *Comments {
+	return c
+}
+
+// A FileSyntax represents an entire go.mod file.
+type FileSyntax struct {
+	Name string // file path
+	Comments
+	Stmt []Expr
+}
+
+func (x *FileSyntax) Span() (start, end Position) {
+	if len(x.Stmt) == 0 {
+		return
+	}
+	start, _ = x.Stmt[0].Span()
+	_, end = x.Stmt[len(x.Stmt)-1].Span()
+	return start, end
+}
+
+// addLine adds a line containing the given tokens to the file.
+//
+// If the first token of the hint matches the first token of the
+// line, the new line is added at the end of the block containing hint,
+// extracting hint into a new block if it is not yet in one.
+//
+// If the hint is non-nil buts its first token does not match,
+// the new line is added after the block containing hint
+// (or hint itself, if not in a block).
+//
+// If no hint is provided, addLine appends the line to the end of
+// the last block with a matching first token,
+// or to the end of the file if no such block exists.
+func (x *FileSyntax) addLine(hint Expr, tokens ...string) *Line {
+	if hint == nil {
+		// If no hint given, add to the last statement of the given type.
+	Loop:
+		for i := len(x.Stmt) - 1; i >= 0; i-- {
+			stmt := x.Stmt[i]
+			switch stmt := stmt.(type) {
+			case *Line:
+				if stmt.Token != nil && stmt.Token[0] == tokens[0] {
+					hint = stmt
+					break Loop
+				}
+			case *LineBlock:
+				if stmt.Token[0] == tokens[0] {
+					hint = stmt
+					break Loop
+				}
+			}
+		}
+	}
+
+	newLineAfter := func(i int) *Line {
+		new := &Line{Token: tokens}
+		if i == len(x.Stmt) {
+			x.Stmt = append(x.Stmt, new)
+		} else {
+			x.Stmt = append(x.Stmt, nil)
+			copy(x.Stmt[i+2:], x.Stmt[i+1:])
+			x.Stmt[i+1] = new
+		}
+		return new
+	}
+
+	if hint != nil {
+		for i, stmt := range x.Stmt {
+			switch stmt := stmt.(type) {
+			case *Line:
+				if stmt == hint {
+					if stmt.Token == nil || stmt.Token[0] != tokens[0] {
+						return newLineAfter(i)
+					}
+
+					// Convert line to line block.
+					stmt.InBlock = true
+					block := &LineBlock{Token: stmt.Token[:1], Line: []*Line{stmt}}
+					stmt.Token = stmt.Token[1:]
+					x.Stmt[i] = block
+					new := &Line{Token: tokens[1:], InBlock: true}
+					block.Line = append(block.Line, new)
+					return new
+				}
+
+			case *LineBlock:
+				if stmt == hint {
+					if stmt.Token[0] != tokens[0] {
+						return newLineAfter(i)
+					}
+
+					new := &Line{Token: tokens[1:], InBlock: true}
+					stmt.Line = append(stmt.Line, new)
+					return new
+				}
+
+				for j, line := range stmt.Line {
+					if line == hint {
+						if stmt.Token[0] != tokens[0] {
+							return newLineAfter(i)
+						}
+
+						// Add new line after hint within the block.
+						stmt.Line = append(stmt.Line, nil)
+						copy(stmt.Line[j+2:], stmt.Line[j+1:])
+						new := &Line{Token: tokens[1:], InBlock: true}
+						stmt.Line[j+1] = new
+						return new
+					}
+				}
+			}
+		}
+	}
+
+	new := &Line{Token: tokens}
+	x.Stmt = append(x.Stmt, new)
+	return new
+}
+
+func (x *FileSyntax) updateLine(line *Line, tokens ...string) {
+	if line.InBlock {
+		tokens = tokens[1:]
+	}
+	line.Token = tokens
+}
+
+// markRemoved modifies line so that it (and its end-of-line comment, if any)
+// will be dropped by (*FileSyntax).Cleanup.
+func (line *Line) markRemoved() {
+	line.Token = nil
+	line.Comments.Suffix = nil
+}
+
+// Cleanup cleans up the file syntax x after any edit operations.
+// To avoid quadratic behavior, (*Line).markRemoved marks the line as dead
+// by setting line.Token = nil but does not remove it from the slice
+// in which it appears. After edits have all been indicated,
+// calling Cleanup cleans out the dead lines.
+func (x *FileSyntax) Cleanup() {
+	w := 0
+	for _, stmt := range x.Stmt {
+		switch stmt := stmt.(type) {
+		case *Line:
+			if stmt.Token == nil {
+				continue
+			}
+		case *LineBlock:
+			ww := 0
+			for _, line := range stmt.Line {
+				if line.Token != nil {
+					stmt.Line[ww] = line
+					ww++
+				}
+			}
+			if ww == 0 {
+				continue
+			}
+			if ww == 1 {
+				// Collapse block into single line.
+				line := &Line{
+					Comments: Comments{
+						Before: commentsAdd(stmt.Before, stmt.Line[0].Before),
+						Suffix: commentsAdd(stmt.Line[0].Suffix, stmt.Suffix),
+						After:  commentsAdd(stmt.Line[0].After, stmt.After),
+					},
+					Token: stringsAdd(stmt.Token, stmt.Line[0].Token),
+				}
+				x.Stmt[w] = line
+				w++
+				continue
+			}
+			stmt.Line = stmt.Line[:ww]
+		}
+		x.Stmt[w] = stmt
+		w++
+	}
+	x.Stmt = x.Stmt[:w]
+}
+
+func commentsAdd(x, y []Comment) []Comment {
+	return append(x[:len(x):len(x)], y...)
+}
+
+func stringsAdd(x, y []string) []string {
+	return append(x[:len(x):len(x)], y...)
+}
+
+// A CommentBlock represents a top-level block of comments separate
+// from any rule.
+type CommentBlock struct {
+	Comments
+	Start Position
+}
+
+func (x *CommentBlock) Span() (start, end Position) {
+	return x.Start, x.Start
+}
+
+// A Line is a single line of tokens.
+type Line struct {
+	Comments
+	Start   Position
+	Token   []string
+	InBlock bool
+	End     Position
+}
+
+func (x *Line) Span() (start, end Position) {
+	return x.Start, x.End
+}
+
+// A LineBlock is a factored block of lines, like
+//
+//	require (
+//		"x"
+//		"y"
+//	)
+type LineBlock struct {
+	Comments
+	Start  Position
+	LParen LParen
+	Token  []string
+	Line   []*Line
+	RParen RParen
+}
+
+func (x *LineBlock) Span() (start, end Position) {
+	return x.Start, x.RParen.Pos.add(")")
+}
+
+// An LParen represents the beginning of a parenthesized line block.
+// It is a place to store suffix comments.
+type LParen struct {
+	Comments
+	Pos Position
+}
+
+func (x *LParen) Span() (start, end Position) {
+	return x.Pos, x.Pos.add(")")
+}
+
+// An RParen represents the end of a parenthesized line block.
+// It is a place to store whole-line (before) comments.
+type RParen struct {
+	Comments
+	Pos Position
+}
+
+func (x *RParen) Span() (start, end Position) {
+	return x.Pos, x.Pos.add(")")
+}
+
+// An input represents a single input file being parsed.
+type input struct {
+	// Lexing state.
+	filename   string    // name of input file, for errors
+	complete   []byte    // entire input
+	remaining  []byte    // remaining input
+	tokenStart []byte    // token being scanned to end of input
+	token      token     // next token to be returned by lex, peek
+	pos        Position  // current input position
+	comments   []Comment // accumulated comments
+
+	// Parser state.
+	file        *FileSyntax // returned top-level syntax tree
+	parseErrors ErrorList   // errors encountered during parsing
+
+	// Comment assignment state.
+	pre  []Expr // all expressions, in preorder traversal
+	post []Expr // all expressions, in postorder traversal
+}
+
+func newInput(filename string, data []byte) *input {
+	return &input{
+		filename:  filename,
+		complete:  data,
+		remaining: data,
+		pos:       Position{Line: 1, LineRune: 1, Byte: 0},
+	}
+}
+
+// parse parses the input file.
+func parse(file string, data []byte) (f *FileSyntax, err error) {
+	// The parser panics for both routine errors like syntax errors
+	// and for programmer bugs like array index errors.
+	// Turn both into error returns. Catching bug panics is
+	// especially important when processing many files.
+	in := newInput(file, data)
+	defer func() {
+		if e := recover(); e != nil && e != &in.parseErrors {
+			in.parseErrors = append(in.parseErrors, Error{
+				Filename: in.filename,
+				Pos:      in.pos,
+				Err:      fmt.Errorf("internal error: %v", e),
+			})
+		}
+		if err == nil && len(in.parseErrors) > 0 {
+			err = in.parseErrors
+		}
+	}()
+
+	// Prime the lexer by reading in the first token. It will be available
+	// in the next peek() or lex() call.
+	in.readToken()
+
+	// Invoke the parser.
+	in.parseFile()
+	if len(in.parseErrors) > 0 {
+		return nil, in.parseErrors
+	}
+	in.file.Name = in.filename
+
+	// Assign comments to nearby syntax.
+	in.assignComments()
+
+	return in.file, nil
+}
+
+// Error is called to report an error.
+// Error does not return: it panics.
+func (in *input) Error(s string) {
+	in.parseErrors = append(in.parseErrors, Error{
+		Filename: in.filename,
+		Pos:      in.pos,
+		Err:      errors.New(s),
+	})
+	panic(&in.parseErrors)
+}
+
+// eof reports whether the input has reached end of file.
+func (in *input) eof() bool {
+	return len(in.remaining) == 0
+}
+
+// peekRune returns the next rune in the input without consuming it.
+func (in *input) peekRune() int {
+	if len(in.remaining) == 0 {
+		return 0
+	}
+	r, _ := utf8.DecodeRune(in.remaining)
+	return int(r)
+}
+
+// peekPrefix reports whether the remaining input begins with the given prefix.
+func (in *input) peekPrefix(prefix string) bool {
+	// This is like bytes.HasPrefix(in.remaining, []byte(prefix))
+	// but without the allocation of the []byte copy of prefix.
+	for i := 0; i < len(prefix); i++ {
+		if i >= len(in.remaining) || in.remaining[i] != prefix[i] {
+			return false
+		}
+	}
+	return true
+}
+
+// readRune consumes and returns the next rune in the input.
+func (in *input) readRune() int {
+	if len(in.remaining) == 0 {
+		in.Error("internal lexer error: readRune at EOF")
+	}
+	r, size := utf8.DecodeRune(in.remaining)
+	in.remaining = in.remaining[size:]
+	if r == '\n' {
+		in.pos.Line++
+		in.pos.LineRune = 1
+	} else {
+		in.pos.LineRune++
+	}
+	in.pos.Byte += size
+	return int(r)
+}
+
+type token struct {
+	kind   tokenKind
+	pos    Position
+	endPos Position
+	text   string
+}
+
+type tokenKind int
+
+const (
+	_EOF tokenKind = -(iota + 1)
+	_EOLCOMMENT
+	_IDENT
+	_STRING
+	_COMMENT
+
+	// newlines and punctuation tokens are allowed as ASCII codes.
+)
+
+func (k tokenKind) isComment() bool {
+	return k == _COMMENT || k == _EOLCOMMENT
+}
+
+// isEOL returns whether a token terminates a line.
+func (k tokenKind) isEOL() bool {
+	return k == _EOF || k == _EOLCOMMENT || k == '\n'
+}
+
+// startToken marks the beginning of the next input token.
+// It must be followed by a call to endToken, once the token's text has
+// been consumed using readRune.
+func (in *input) startToken() {
+	in.tokenStart = in.remaining
+	in.token.text = ""
+	in.token.pos = in.pos
+}
+
+// endToken marks the end of an input token.
+// It records the actual token string in tok.text.
+// A single trailing newline (LF or CRLF) will be removed from comment tokens.
+func (in *input) endToken(kind tokenKind) {
+	in.token.kind = kind
+	text := string(in.tokenStart[:len(in.tokenStart)-len(in.remaining)])
+	if kind.isComment() {
+		if strings.HasSuffix(text, "\r\n") {
+			text = text[:len(text)-2]
+		} else {
+			text = strings.TrimSuffix(text, "\n")
+		}
+	}
+	in.token.text = text
+	in.token.endPos = in.pos
+}
+
+// peek returns the kind of the next token returned by lex.
+func (in *input) peek() tokenKind {
+	return in.token.kind
+}
+
+// lex is called from the parser to obtain the next input token.
+func (in *input) lex() token {
+	tok := in.token
+	in.readToken()
+	return tok
+}
+
+// readToken lexes the next token from the text and stores it in in.token.
+func (in *input) readToken() {
+	// Skip past spaces, stopping at non-space or EOF.
+	for !in.eof() {
+		c := in.peekRune()
+		if c == ' ' || c == '\t' || c == '\r' {
+			in.readRune()
+			continue
+		}
+
+		// Comment runs to end of line.
+		if in.peekPrefix("//") {
+			in.startToken()
+
+			// Is this comment the only thing on its line?
+			// Find the last \n before this // and see if it's all
+			// spaces from there to here.
+			i := bytes.LastIndex(in.complete[:in.pos.Byte], []byte("\n"))
+			suffix := len(bytes.TrimSpace(in.complete[i+1:in.pos.Byte])) > 0
+			in.readRune()
+			in.readRune()
+
+			// Consume comment.
+			for len(in.remaining) > 0 && in.readRune() != '\n' {
+			}
+
+			// If we are at top level (not in a statement), hand the comment to
+			// the parser as a _COMMENT token. The grammar is written
+			// to handle top-level comments itself.
+			if !suffix {
+				in.endToken(_COMMENT)
+				return
+			}
+
+			// Otherwise, save comment for later attachment to syntax tree.
+			in.endToken(_EOLCOMMENT)
+			in.comments = append(in.comments, Comment{in.token.pos, in.token.text, suffix})
+			return
+		}
+
+		if in.peekPrefix("/*") {
+			in.Error("mod files must use // comments (not /* */ comments)")
+		}
+
+		// Found non-space non-comment.
+		break
+	}
+
+	// Found the beginning of the next token.
+	in.startToken()
+
+	// End of file.
+	if in.eof() {
+		in.endToken(_EOF)
+		return
+	}
+
+	// Punctuation tokens.
+	switch c := in.peekRune(); c {
+	case '\n', '(', ')', '[', ']', '{', '}', ',':
+		in.readRune()
+		in.endToken(tokenKind(c))
+		return
+
+	case '"', '`': // quoted string
+		quote := c
+		in.readRune()
+		for {
+			if in.eof() {
+				in.pos = in.token.pos
+				in.Error("unexpected EOF in string")
+			}
+			if in.peekRune() == '\n' {
+				in.Error("unexpected newline in string")
+			}
+			c := in.readRune()
+			if c == quote {
+				break
+			}
+			if c == '\\' && quote != '`' {
+				if in.eof() {
+					in.pos = in.token.pos
+					in.Error("unexpected EOF in string")
+				}
+				in.readRune()
+			}
+		}
+		in.endToken(_STRING)
+		return
+	}
+
+	// Checked all punctuation. Must be identifier token.
+	if c := in.peekRune(); !isIdent(c) {
+		in.Error(fmt.Sprintf("unexpected input character %#q", c))
+	}
+
+	// Scan over identifier.
+	for isIdent(in.peekRune()) {
+		if in.peekPrefix("//") {
+			break
+		}
+		if in.peekPrefix("/*") {
+			in.Error("mod files must use // comments (not /* */ comments)")
+		}
+		in.readRune()
+	}
+	in.endToken(_IDENT)
+}
+
+// isIdent reports whether c is an identifier rune.
+// We treat most printable runes as identifier runes, except for a handful of
+// ASCII punctuation characters.
+func isIdent(c int) bool {
+	switch r := rune(c); r {
+	case ' ', '(', ')', '[', ']', '{', '}', ',':
+		return false
+	default:
+		return !unicode.IsSpace(r) && unicode.IsPrint(r)
+	}
+}
+
+// Comment assignment.
+// We build two lists of all subexpressions, preorder and postorder.
+// The preorder list is ordered by start location, with outer expressions first.
+// The postorder list is ordered by end location, with outer expressions last.
+// We use the preorder list to assign each whole-line comment to the syntax
+// immediately following it, and we use the postorder list to assign each
+// end-of-line comment to the syntax immediately preceding it.
+
+// order walks the expression adding it and its subexpressions to the
+// preorder and postorder lists.
+func (in *input) order(x Expr) {
+	if x != nil {
+		in.pre = append(in.pre, x)
+	}
+	switch x := x.(type) {
+	default:
+		panic(fmt.Errorf("order: unexpected type %T", x))
+	case nil:
+		// nothing
+	case *LParen, *RParen:
+		// nothing
+	case *CommentBlock:
+		// nothing
+	case *Line:
+		// nothing
+	case *FileSyntax:
+		for _, stmt := range x.Stmt {
+			in.order(stmt)
+		}
+	case *LineBlock:
+		in.order(&x.LParen)
+		for _, l := range x.Line {
+			in.order(l)
+		}
+		in.order(&x.RParen)
+	}
+	if x != nil {
+		in.post = append(in.post, x)
+	}
+}
+
+// assignComments attaches comments to nearby syntax.
+func (in *input) assignComments() {
+	const debug = false
+
+	// Generate preorder and postorder lists.
+	in.order(in.file)
+
+	// Split into whole-line comments and suffix comments.
+	var line, suffix []Comment
+	for _, com := range in.comments {
+		if com.Suffix {
+			suffix = append(suffix, com)
+		} else {
+			line = append(line, com)
+		}
+	}
+
+	if debug {
+		for _, c := range line {
+			fmt.Fprintf(os.Stderr, "LINE %q :%d:%d #%d\n", c.Token, c.Start.Line, c.Start.LineRune, c.Start.Byte)
+		}
+	}
+
+	// Assign line comments to syntax immediately following.
+	for _, x := range in.pre {
+		start, _ := x.Span()
+		if debug {
+			fmt.Fprintf(os.Stderr, "pre %T :%d:%d #%d\n", x, start.Line, start.LineRune, start.Byte)
+		}
+		xcom := x.Comment()
+		for len(line) > 0 && start.Byte >= line[0].Start.Byte {
+			if debug {
+				fmt.Fprintf(os.Stderr, "ASSIGN LINE %q #%d\n", line[0].Token, line[0].Start.Byte)
+			}
+			xcom.Before = append(xcom.Before, line[0])
+			line = line[1:]
+		}
+	}
+
+	// Remaining line comments go at end of file.
+	in.file.After = append(in.file.After, line...)
+
+	if debug {
+		for _, c := range suffix {
+			fmt.Fprintf(os.Stderr, "SUFFIX %q :%d:%d #%d\n", c.Token, c.Start.Line, c.Start.LineRune, c.Start.Byte)
+		}
+	}
+
+	// Assign suffix comments to syntax immediately before.
+	for i := len(in.post) - 1; i >= 0; i-- {
+		x := in.post[i]
+
+		start, end := x.Span()
+		if debug {
+			fmt.Fprintf(os.Stderr, "post %T :%d:%d #%d :%d:%d #%d\n", x, start.Line, start.LineRune, start.Byte, end.Line, end.LineRune, end.Byte)
+		}
+
+		// Do not assign suffix comments to end of line block or whole file.
+		// Instead assign them to the last element inside.
+		switch x.(type) {
+		case *FileSyntax:
+			continue
+		}
+
+		// Do not assign suffix comments to something that starts
+		// on an earlier line, so that in
+		//
+		//	x ( y
+		//		z ) // comment
+		//
+		// we assign the comment to z and not to x ( ... ).
+		if start.Line != end.Line {
+			continue
+		}
+		xcom := x.Comment()
+		for len(suffix) > 0 && end.Byte <= suffix[len(suffix)-1].Start.Byte {
+			if debug {
+				fmt.Fprintf(os.Stderr, "ASSIGN SUFFIX %q #%d\n", suffix[len(suffix)-1].Token, suffix[len(suffix)-1].Start.Byte)
+			}
+			xcom.Suffix = append(xcom.Suffix, suffix[len(suffix)-1])
+			suffix = suffix[:len(suffix)-1]
+		}
+	}
+
+	// We assigned suffix comments in reverse.
+	// If multiple suffix comments were appended to the same
+	// expression node, they are now in reverse. Fix that.
+	for _, x := range in.post {
+		reverseComments(x.Comment().Suffix)
+	}
+
+	// Remaining suffix comments go at beginning of file.
+	in.file.Before = append(in.file.Before, suffix...)
+}
+
+// reverseComments reverses the []Comment list.
+func reverseComments(list []Comment) {
+	for i, j := 0, len(list)-1; i < j; i, j = i+1, j-1 {
+		list[i], list[j] = list[j], list[i]
+	}
+}
+
+func (in *input) parseFile() {
+	in.file = new(FileSyntax)
+	var cb *CommentBlock
+	for {
+		switch in.peek() {
+		case '\n':
+			in.lex()
+			if cb != nil {
+				in.file.Stmt = append(in.file.Stmt, cb)
+				cb = nil
+			}
+		case _COMMENT:
+			tok := in.lex()
+			if cb == nil {
+				cb = &CommentBlock{Start: tok.pos}
+			}
+			com := cb.Comment()
+			com.Before = append(com.Before, Comment{Start: tok.pos, Token: tok.text})
+		case _EOF:
+			if cb != nil {
+				in.file.Stmt = append(in.file.Stmt, cb)
+			}
+			return
+		default:
+			in.parseStmt()
+			if cb != nil {
+				in.file.Stmt[len(in.file.Stmt)-1].Comment().Before = cb.Before
+				cb = nil
+			}
+		}
+	}
+}
+
+func (in *input) parseStmt() {
+	tok := in.lex()
+	start := tok.pos
+	end := tok.endPos
+	tokens := []string{tok.text}
+	for {
+		tok := in.lex()
+		switch {
+		case tok.kind.isEOL():
+			in.file.Stmt = append(in.file.Stmt, &Line{
+				Start: start,
+				Token: tokens,
+				End:   end,
+			})
+			return
+
+		case tok.kind == '(':
+			if next := in.peek(); next.isEOL() {
+				// Start of block: no more tokens on this line.
+				in.file.Stmt = append(in.file.Stmt, in.parseLineBlock(start, tokens, tok))
+				return
+			} else if next == ')' {
+				rparen := in.lex()
+				if in.peek().isEOL() {
+					// Empty block.
+					in.lex()
+					in.file.Stmt = append(in.file.Stmt, &LineBlock{
+						Start:  start,
+						Token:  tokens,
+						LParen: LParen{Pos: tok.pos},
+						RParen: RParen{Pos: rparen.pos},
+					})
+					return
+				}
+				// '( )' in the middle of the line, not a block.
+				tokens = append(tokens, tok.text, rparen.text)
+			} else {
+				// '(' in the middle of the line, not a block.
+				tokens = append(tokens, tok.text)
+			}
+
+		default:
+			tokens = append(tokens, tok.text)
+			end = tok.endPos
+		}
+	}
+}
+
+func (in *input) parseLineBlock(start Position, token []string, lparen token) *LineBlock {
+	x := &LineBlock{
+		Start:  start,
+		Token:  token,
+		LParen: LParen{Pos: lparen.pos},
+	}
+	var comments []Comment
+	for {
+		switch in.peek() {
+		case _EOLCOMMENT:
+			// Suffix comment, will be attached later by assignComments.
+			in.lex()
+		case '\n':
+			// Blank line. Add an empty comment to preserve it.
+			in.lex()
+			if len(comments) == 0 && len(x.Line) > 0 || len(comments) > 0 && comments[len(comments)-1].Token != "" {
+				comments = append(comments, Comment{})
+			}
+		case _COMMENT:
+			tok := in.lex()
+			comments = append(comments, Comment{Start: tok.pos, Token: tok.text})
+		case _EOF:
+			in.Error(fmt.Sprintf("syntax error (unterminated block started at %s:%d:%d)", in.filename, x.Start.Line, x.Start.LineRune))
+		case ')':
+			rparen := in.lex()
+			x.RParen.Before = comments
+			x.RParen.Pos = rparen.pos
+			if !in.peek().isEOL() {
+				in.Error("syntax error (expected newline after closing paren)")
+			}
+			in.lex()
+			return x
+		default:
+			l := in.parseLine()
+			x.Line = append(x.Line, l)
+			l.Comment().Before = comments
+			comments = nil
+		}
+	}
+}
+
+func (in *input) parseLine() *Line {
+	tok := in.lex()
+	if tok.kind.isEOL() {
+		in.Error("internal parse error: parseLine at end of line")
+	}
+	start := tok.pos
+	end := tok.endPos
+	tokens := []string{tok.text}
+	for {
+		tok := in.lex()
+		if tok.kind.isEOL() {
+			return &Line{
+				Start:   start,
+				Token:   tokens,
+				End:     end,
+				InBlock: true,
+			}
+		}
+		tokens = append(tokens, tok.text)
+		end = tok.endPos
+	}
+}
+
+var (
+	slashSlash = []byte("//")
+	moduleStr  = []byte("module")
+)
+
+// ModulePath returns the module path from the gomod file text.
+// If it cannot find a module path, it returns an empty string.
+// It is tolerant of unrelated problems in the go.mod file.
+func ModulePath(mod []byte) string {
+	for len(mod) > 0 {
+		line := mod
+		mod = nil
+		if i := bytes.IndexByte(line, '\n'); i >= 0 {
+			line, mod = line[:i], line[i+1:]
+		}
+		if i := bytes.Index(line, slashSlash); i >= 0 {
+			line = line[:i]
+		}
+		line = bytes.TrimSpace(line)
+		if !bytes.HasPrefix(line, moduleStr) {
+			continue
+		}
+		line = line[len(moduleStr):]
+		n := len(line)
+		line = bytes.TrimSpace(line)
+		if len(line) == n || len(line) == 0 {
+			continue
+		}
+
+		if line[0] == '"' || line[0] == '`' {
+			p, err := strconv.Unquote(string(line))
+			if err != nil {
+				return "" // malformed quoted string or multiline module path
+			}
+			return p
+		}
+
+		return string(line)
+	}
+	return "" // missing module path
+}

vendor/golang.org/x/mod/modfile/work.go

@@ -0,0 +1,234 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package modfile
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// A WorkFile is the parsed, interpreted form of a go.work file.
+type WorkFile struct {
+	Go      *Go
+	Use     []*Use
+	Replace []*Replace
+
+	Syntax *FileSyntax
+}
+
+// A Use is a single directory statement.
+type Use struct {
+	Path       string // Use path of module.
+	ModulePath string // Module path in the comment.
+	Syntax     *Line
+}
+
+// ParseWork parses and returns a go.work file.
+//
+// file is the name of the file, used in positions and errors.
+//
+// data is the content of the file.
+//
+// fix is an optional function that canonicalizes module versions.
+// If fix is nil, all module versions must be canonical (module.CanonicalVersion
+// must return the same string).
+func ParseWork(file string, data []byte, fix VersionFixer) (*WorkFile, error) {
+	fs, err := parse(file, data)
+	if err != nil {
+		return nil, err
+	}
+	f := &WorkFile{
+		Syntax: fs,
+	}
+	var errs ErrorList
+
+	for _, x := range fs.Stmt {
+		switch x := x.(type) {
+		case *Line:
+			f.add(&errs, x, x.Token[0], x.Token[1:], fix)
+
+		case *LineBlock:
+			if len(x.Token) > 1 {
+				errs = append(errs, Error{
+					Filename: file,
+					Pos:      x.Start,
+					Err:      fmt.Errorf("unknown block type: %s", strings.Join(x.Token, " ")),
+				})
+				continue
+			}
+			switch x.Token[0] {
+			default:
+				errs = append(errs, Error{
+					Filename: file,
+					Pos:      x.Start,
+					Err:      fmt.Errorf("unknown block type: %s", strings.Join(x.Token, " ")),
+				})
+				continue
+			case "use", "replace":
+				for _, l := range x.Line {
+					f.add(&errs, l, x.Token[0], l.Token, fix)
+				}
+			}
+		}
+	}
+
+	if len(errs) > 0 {
+		return nil, errs
+	}
+	return f, nil
+}
+
+// Cleanup cleans up the file f after any edit operations.
+// To avoid quadratic behavior, modifications like DropRequire
+// clear the entry but do not remove it from the slice.
+// Cleanup cleans out all the cleared entries.
+func (f *WorkFile) Cleanup() {
+	w := 0
+	for _, r := range f.Use {
+		if r.Path != "" {
+			f.Use[w] = r
+			w++
+		}
+	}
+	f.Use = f.Use[:w]
+
+	w = 0
+	for _, r := range f.Replace {
+		if r.Old.Path != "" {
+			f.Replace[w] = r
+			w++
+		}
+	}
+	f.Replace = f.Replace[:w]
+
+	f.Syntax.Cleanup()
+}
+
+func (f *WorkFile) AddGoStmt(version string) error {
+	if !GoVersionRE.MatchString(version) {
+		return fmt.Errorf("invalid language version string %q", version)
+	}
+	if f.Go == nil {
+		stmt := &Line{Token: []string{"go", version}}
+		f.Go = &Go{
+			Version: version,
+			Syntax:  stmt,
+		}
+		// Find the first non-comment-only block that's and add
+		// the go statement before it. That will keep file comments at the top.
+		i := 0
+		for i = 0; i < len(f.Syntax.Stmt); i++ {
+			if _, ok := f.Syntax.Stmt[i].(*CommentBlock); !ok {
+				break
+			}
+		}
+		f.Syntax.Stmt = append(append(f.Syntax.Stmt[:i:i], stmt), f.Syntax.Stmt[i:]...)
+	} else {
+		f.Go.Version = version
+		f.Syntax.updateLine(f.Go.Syntax, "go", version)
+	}
+	return nil
+}
+
+func (f *WorkFile) AddUse(diskPath, modulePath string) error {
+	need := true
+	for _, d := range f.Use {
+		if d.Path == diskPath {
+			if need {
+				d.ModulePath = modulePath
+				f.Syntax.updateLine(d.Syntax, "use", AutoQuote(diskPath))
+				need = false
+			} else {
+				d.Syntax.markRemoved()
+				*d = Use{}
+			}
+		}
+	}
+
+	if need {
+		f.AddNewUse(diskPath, modulePath)
+	}
+	return nil
+}
+
+func (f *WorkFile) AddNewUse(diskPath, modulePath string) {
+	line := f.Syntax.addLine(nil, "use", AutoQuote(diskPath))
+	f.Use = append(f.Use, &Use{Path: diskPath, ModulePath: modulePath, Syntax: line})
+}
+
+func (f *WorkFile) SetUse(dirs []*Use) {
+	need := make(map[string]string)
+	for _, d := range dirs {
+		need[d.Path] = d.ModulePath
+	}
+
+	for _, d := range f.Use {
+		if modulePath, ok := need[d.Path]; ok {
+			d.ModulePath = modulePath
+		} else {
+			d.Syntax.markRemoved()
+			*d = Use{}
+		}
+	}
+
+	// TODO(#45713): Add module path to comment.
+
+	for diskPath, modulePath := range need {
+		f.AddNewUse(diskPath, modulePath)
+	}
+	f.SortBlocks()
+}
+
+func (f *WorkFile) DropUse(path string) error {
+	for _, d := range f.Use {
+		if d.Path == path {
+			d.Syntax.markRemoved()
+			*d = Use{}
+		}
+	}
+	return nil
+}
+
+func (f *WorkFile) AddReplace(oldPath, oldVers, newPath, newVers string) error {
+	return addReplace(f.Syntax, &f.Replace, oldPath, oldVers, newPath, newVers)
+}
+
+func (f *WorkFile) DropReplace(oldPath, oldVers string) error {
+	for _, r := range f.Replace {
+		if r.Old.Path == oldPath && r.Old.Version == oldVers {
+			r.Syntax.markRemoved()
+			*r = Replace{}
+		}
+	}
+	return nil
+}
+
+func (f *WorkFile) SortBlocks() {
+	f.removeDups() // otherwise sorting is unsafe
+
+	for _, stmt := range f.Syntax.Stmt {
+		block, ok := stmt.(*LineBlock)
+		if !ok {
+			continue
+		}
+		sort.SliceStable(block.Line, func(i, j int) bool {
+			return lineLess(block.Line[i], block.Line[j])
+		})
+	}
+}
+
+// removeDups removes duplicate replace directives.
+//
+// Later replace directives take priority.
+//
+// require directives are not de-duplicated. That's left up to higher-level
+// logic (MVS).
+//
+// retract directives are not de-duplicated since comments are
+// meaningful, and versions may be retracted multiple times.
+func (f *WorkFile) removeDups() {
+	removeDups(f.Syntax, nil, &f.Replace)
+}

vendor/golang.org/x/mod/module/module.go

@@ -0,0 +1,841 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package module defines the module.Version type along with support code.
+//
+// The module.Version type is a simple Path, Version pair:
+//
+//	type Version struct {
+//		Path string
+//		Version string
+//	}
+//
+// There are no restrictions imposed directly by use of this structure,
+// but additional checking functions, most notably Check, verify that
+// a particular path, version pair is valid.
+//
+// # Escaped Paths
+//
+// Module paths appear as substrings of file system paths
+// (in the download cache) and of web server URLs in the proxy protocol.
+// In general we cannot rely on file systems to be case-sensitive,
+// nor can we rely on web servers, since they read from file systems.
+// That is, we cannot rely on the file system to keep rsc.io/QUOTE
+// and rsc.io/quote separate. Windows and macOS don't.
+// Instead, we must never require two different casings of a file path.
+// Because we want the download cache to match the proxy protocol,
+// and because we want the proxy protocol to be possible to serve
+// from a tree of static files (which might be stored on a case-insensitive
+// file system), the proxy protocol must never require two different casings
+// of a URL path either.
+//
+// One possibility would be to make the escaped form be the lowercase
+// hexadecimal encoding of the actual path bytes. This would avoid ever
+// needing different casings of a file path, but it would be fairly illegible
+// to most programmers when those paths appeared in the file system
+// (including in file paths in compiler errors and stack traces)
+// in web server logs, and so on. Instead, we want a safe escaped form that
+// leaves most paths unaltered.
+//
+// The safe escaped form is to replace every uppercase letter
+// with an exclamation mark followed by the letter's lowercase equivalent.
+//
+// For example,
+//
+//	github.com/Azure/azure-sdk-for-go ->  github.com/!azure/azure-sdk-for-go.
+//	github.com/GoogleCloudPlatform/cloudsql-proxy -> github.com/!google!cloud!platform/cloudsql-proxy
+//	github.com/Sirupsen/logrus -> github.com/!sirupsen/logrus.
+//
+// Import paths that avoid upper-case letters are left unchanged.
+// Note that because import paths are ASCII-only and avoid various
+// problematic punctuation (like : < and >), the escaped form is also ASCII-only
+// and avoids the same problematic punctuation.
+//
+// Import paths have never allowed exclamation marks, so there is no
+// need to define how to escape a literal !.
+//
+// # Unicode Restrictions
+//
+// Today, paths are disallowed from using Unicode.
+//
+// Although paths are currently disallowed from using Unicode,
+// we would like at some point to allow Unicode letters as well, to assume that
+// file systems and URLs are Unicode-safe (storing UTF-8), and apply
+// the !-for-uppercase convention for escaping them in the file system.
+// But there are at least two subtle considerations.
+//
+// First, note that not all case-fold equivalent distinct runes
+// form an upper/lower pair.
+// For example, U+004B ('K'), U+006B ('k'), and U+212A ('K' for Kelvin)
+// are three distinct runes that case-fold to each other.
+// When we do add Unicode letters, we must not assume that upper/lower
+// are the only case-equivalent pairs.
+// Perhaps the Kelvin symbol would be disallowed entirely, for example.
+// Or perhaps it would escape as "!!k", or perhaps as "(212A)".
+//
+// Second, it would be nice to allow Unicode marks as well as letters,
+// but marks include combining marks, and then we must deal not
+// only with case folding but also normalization: both U+00E9 ('é')
+// and U+0065 U+0301 ('e' followed by combining acute accent)
+// look the same on the page and are treated by some file systems
+// as the same path. If we do allow Unicode marks in paths, there
+// must be some kind of normalization to allow only one canonical
+// encoding of any character used in an import path.
+package module
+
+// IMPORTANT NOTE
+//
+// This file essentially defines the set of valid import paths for the go command.
+// There are many subtle considerations, including Unicode ambiguity,
+// security, network, and file system representations.
+//
+// This file also defines the set of valid module path and version combinations,
+// another topic with many subtle considerations.
+//
+// Changes to the semantics in this file require approval from rsc.
+
+import (
+	"errors"
+	"fmt"
+	"path"
+	"sort"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"golang.org/x/mod/semver"
+)
+
+// A Version (for clients, a module.Version) is defined by a module path and version pair.
+// These are stored in their plain (unescaped) form.
+type Version struct {
+	// Path is a module path, like "golang.org/x/text" or "rsc.io/quote/v2".
+	Path string
+
+	// Version is usually a semantic version in canonical form.
+	// There are three exceptions to this general rule.
+	// First, the top-level target of a build has no specific version
+	// and uses Version = "".
+	// Second, during MVS calculations the version "none" is used
+	// to represent the decision to take no version of a given module.
+	// Third, filesystem paths found in "replace" directives are
+	// represented by a path with an empty version.
+	Version string `json:",omitempty"`
+}
+
+// String returns a representation of the Version suitable for logging
+// (Path@Version, or just Path if Version is empty).
+func (m Version) String() string {
+	if m.Version == "" {
+		return m.Path
+	}
+	return m.Path + "@" + m.Version
+}
+
+// A ModuleError indicates an error specific to a module.
+type ModuleError struct {
+	Path    string
+	Version string
+	Err     error
+}
+
+// VersionError returns a ModuleError derived from a Version and error,
+// or err itself if it is already such an error.
+func VersionError(v Version, err error) error {
+	var mErr *ModuleError
+	if errors.As(err, &mErr) && mErr.Path == v.Path && mErr.Version == v.Version {
+		return err
+	}
+	return &ModuleError{
+		Path:    v.Path,
+		Version: v.Version,
+		Err:     err,
+	}
+}
+
+func (e *ModuleError) Error() string {
+	if v, ok := e.Err.(*InvalidVersionError); ok {
+		return fmt.Sprintf("%s@%s: invalid %s: %v", e.Path, v.Version, v.noun(), v.Err)
+	}
+	if e.Version != "" {
+		return fmt.Sprintf("%s@%s: %v", e.Path, e.Version, e.Err)
+	}
+	return fmt.Sprintf("module %s: %v", e.Path, e.Err)
+}
+
+func (e *ModuleError) Unwrap() error { return e.Err }
+
+// An InvalidVersionError indicates an error specific to a version, with the
+// module path unknown or specified externally.
+//
+// A ModuleError may wrap an InvalidVersionError, but an InvalidVersionError
+// must not wrap a ModuleError.
+type InvalidVersionError struct {
+	Version string
+	Pseudo  bool
+	Err     error
+}
+
+// noun returns either "version" or "pseudo-version", depending on whether
+// e.Version is a pseudo-version.
+func (e *InvalidVersionError) noun() string {
+	if e.Pseudo {
+		return "pseudo-version"
+	}
+	return "version"
+}
+
+func (e *InvalidVersionError) Error() string {
+	return fmt.Sprintf("%s %q invalid: %s", e.noun(), e.Version, e.Err)
+}
+
+func (e *InvalidVersionError) Unwrap() error { return e.Err }
+
+// An InvalidPathError indicates a module, import, or file path doesn't
+// satisfy all naming constraints. See CheckPath, CheckImportPath,
+// and CheckFilePath for specific restrictions.
+type InvalidPathError struct {
+	Kind string // "module", "import", or "file"
+	Path string
+	Err  error
+}
+
+func (e *InvalidPathError) Error() string {
+	return fmt.Sprintf("malformed %s path %q: %v", e.Kind, e.Path, e.Err)
+}
+
+func (e *InvalidPathError) Unwrap() error { return e.Err }
+
+// Check checks that a given module path, version pair is valid.
+// In addition to the path being a valid module path
+// and the version being a valid semantic version,
+// the two must correspond.
+// For example, the path "yaml/v2" only corresponds to
+// semantic versions beginning with "v2.".
+func Check(path, version string) error {
+	if err := CheckPath(path); err != nil {
+		return err
+	}
+	if !semver.IsValid(version) {
+		return &ModuleError{
+			Path: path,
+			Err:  &InvalidVersionError{Version: version, Err: errors.New("not a semantic version")},
+		}
+	}
+	_, pathMajor, _ := SplitPathVersion(path)
+	if err := CheckPathMajor(version, pathMajor); err != nil {
+		return &ModuleError{Path: path, Err: err}
+	}
+	return nil
+}
+
+// firstPathOK reports whether r can appear in the first element of a module path.
+// The first element of the path must be an LDH domain name, at least for now.
+// To avoid case ambiguity, the domain name must be entirely lower case.
+func firstPathOK(r rune) bool {
+	return r == '-' || r == '.' ||
+		'0' <= r && r <= '9' ||
+		'a' <= r && r <= 'z'
+}
+
+// modPathOK reports whether r can appear in a module path element.
+// Paths can be ASCII letters, ASCII digits, and limited ASCII punctuation: - . _ and ~.
+//
+// This matches what "go get" has historically recognized in import paths,
+// and avoids confusing sequences like '%20' or '+' that would change meaning
+// if used in a URL.
+//
+// TODO(rsc): We would like to allow Unicode letters, but that requires additional
+// care in the safe encoding (see "escaped paths" above).
+func modPathOK(r rune) bool {
+	if r < utf8.RuneSelf {
+		return r == '-' || r == '.' || r == '_' || r == '~' ||
+			'0' <= r && r <= '9' ||
+			'A' <= r && r <= 'Z' ||
+			'a' <= r && r <= 'z'
+	}
+	return false
+}
+
+// importPathOK reports whether r can appear in a package import path element.
+//
+// Import paths are intermediate between module paths and file paths: we allow
+// disallow characters that would be confusing or ambiguous as arguments to
+// 'go get' (such as '@' and ' ' ), but allow certain characters that are
+// otherwise-unambiguous on the command line and historically used for some
+// binary names (such as '++' as a suffix for compiler binaries and wrappers).
+func importPathOK(r rune) bool {
+	return modPathOK(r) || r == '+'
+}
+
+// fileNameOK reports whether r can appear in a file name.
+// For now we allow all Unicode letters but otherwise limit to pathOK plus a few more punctuation characters.
+// If we expand the set of allowed characters here, we have to
+// work harder at detecting potential case-folding and normalization collisions.
+// See note about "escaped paths" above.
+func fileNameOK(r rune) bool {
+	if r < utf8.RuneSelf {
+		// Entire set of ASCII punctuation, from which we remove characters:
+		//     ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \ ] ^ _ ` { | } ~
+		// We disallow some shell special characters: " ' * < > ? ` |
+		// (Note that some of those are disallowed by the Windows file system as well.)
+		// We also disallow path separators / : and \ (fileNameOK is only called on path element characters).
+		// We allow spaces (U+0020) in file names.
+		const allowed = "!#$%&()+,-.=@[]^_{}~ "
+		if '0' <= r && r <= '9' || 'A' <= r && r <= 'Z' || 'a' <= r && r <= 'z' {
+			return true
+		}
+		return strings.ContainsRune(allowed, r)
+	}
+	// It may be OK to add more ASCII punctuation here, but only carefully.
+	// For example Windows disallows < > \, and macOS disallows :, so we must not allow those.
+	return unicode.IsLetter(r)
+}
+
+// CheckPath checks that a module path is valid.
+// A valid module path is a valid import path, as checked by CheckImportPath,
+// with three additional constraints.
+// First, the leading path element (up to the first slash, if any),
+// by convention a domain name, must contain only lower-case ASCII letters,
+// ASCII digits, dots (U+002E), and dashes (U+002D);
+// it must contain at least one dot and cannot start with a dash.
+// Second, for a final path element of the form /vN, where N looks numeric
+// (ASCII digits and dots) must not begin with a leading zero, must not be /v1,
+// and must not contain any dots. For paths beginning with "gopkg.in/",
+// this second requirement is replaced by a requirement that the path
+// follow the gopkg.in server's conventions.
+// Third, no path element may begin with a dot.
+func CheckPath(path string) (err error) {
+	defer func() {
+		if err != nil {
+			err = &InvalidPathError{Kind: "module", Path: path, Err: err}
+		}
+	}()
+
+	if err := checkPath(path, modulePath); err != nil {
+		return err
+	}
+	i := strings.Index(path, "/")
+	if i < 0 {
+		i = len(path)
+	}
+	if i == 0 {
+		return fmt.Errorf("leading slash")
+	}
+	if !strings.Contains(path[:i], ".") {
+		return fmt.Errorf("missing dot in first path element")
+	}
+	if path[0] == '-' {
+		return fmt.Errorf("leading dash in first path element")
+	}
+	for _, r := range path[:i] {
+		if !firstPathOK(r) {
+			return fmt.Errorf("invalid char %q in first path element", r)
+		}
+	}
+	if _, _, ok := SplitPathVersion(path); !ok {
+		return fmt.Errorf("invalid version")
+	}
+	return nil
+}
+
+// CheckImportPath checks that an import path is valid.
+//
+// A valid import path consists of one or more valid path elements
+// separated by slashes (U+002F). (It must not begin with nor end in a slash.)
+//
+// A valid path element is a non-empty string made up of
+// ASCII letters, ASCII digits, and limited ASCII punctuation: - . _ and ~.
+// It must not end with a dot (U+002E), nor contain two dots in a row.
+//
+// The element prefix up to the first dot must not be a reserved file name
+// on Windows, regardless of case (CON, com1, NuL, and so on). The element
+// must not have a suffix of a tilde followed by one or more ASCII digits
+// (to exclude paths elements that look like Windows short-names).
+//
+// CheckImportPath may be less restrictive in the future, but see the
+// top-level package documentation for additional information about
+// subtleties of Unicode.
+func CheckImportPath(path string) error {
+	if err := checkPath(path, importPath); err != nil {
+		return &InvalidPathError{Kind: "import", Path: path, Err: err}
+	}
+	return nil
+}
+
+// pathKind indicates what kind of path we're checking. Module paths,
+// import paths, and file paths have different restrictions.
+type pathKind int
+
+const (
+	modulePath pathKind = iota
+	importPath
+	filePath
+)
+
+// checkPath checks that a general path is valid. kind indicates what
+// specific constraints should be applied.
+//
+// checkPath returns an error describing why the path is not valid.
+// Because these checks apply to module, import, and file paths,
+// and because other checks may be applied, the caller is expected to wrap
+// this error with InvalidPathError.
+func checkPath(path string, kind pathKind) error {
+	if !utf8.ValidString(path) {
+		return fmt.Errorf("invalid UTF-8")
+	}
+	if path == "" {
+		return fmt.Errorf("empty string")
+	}
+	if path[0] == '-' && kind != filePath {
+		return fmt.Errorf("leading dash")
+	}
+	if strings.Contains(path, "//") {
+		return fmt.Errorf("double slash")
+	}
+	if path[len(path)-1] == '/' {
+		return fmt.Errorf("trailing slash")
+	}
+	elemStart := 0
+	for i, r := range path {
+		if r == '/' {
+			if err := checkElem(path[elemStart:i], kind); err != nil {
+				return err
+			}
+			elemStart = i + 1
+		}
+	}
+	if err := checkElem(path[elemStart:], kind); err != nil {
+		return err
+	}
+	return nil
+}
+
+// checkElem checks whether an individual path element is valid.
+func checkElem(elem string, kind pathKind) error {
+	if elem == "" {
+		return fmt.Errorf("empty path element")
+	}
+	if strings.Count(elem, ".") == len(elem) {
+		return fmt.Errorf("invalid path element %q", elem)
+	}
+	if elem[0] == '.' && kind == modulePath {
+		return fmt.Errorf("leading dot in path element")
+	}
+	if elem[len(elem)-1] == '.' {
+		return fmt.Errorf("trailing dot in path element")
+	}
+	for _, r := range elem {
+		ok := false
+		switch kind {
+		case modulePath:
+			ok = modPathOK(r)
+		case importPath:
+			ok = importPathOK(r)
+		case filePath:
+			ok = fileNameOK(r)
+		default:
+			panic(fmt.Sprintf("internal error: invalid kind %v", kind))
+		}
+		if !ok {
+			return fmt.Errorf("invalid char %q", r)
+		}
+	}
+
+	// Windows disallows a bunch of path elements, sadly.
+	// See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
+	short := elem
+	if i := strings.Index(short, "."); i >= 0 {
+		short = short[:i]
+	}
+	for _, bad := range badWindowsNames {
+		if strings.EqualFold(bad, short) {
+			return fmt.Errorf("%q disallowed as path element component on Windows", short)
+		}
+	}
+
+	if kind == filePath {
+		// don't check for Windows short-names in file names. They're
+		// only an issue for import paths.
+		return nil
+	}
+
+	// Reject path components that look like Windows short-names.
+	// Those usually end in a tilde followed by one or more ASCII digits.
+	if tilde := strings.LastIndexByte(short, '~'); tilde >= 0 && tilde < len(short)-1 {
+		suffix := short[tilde+1:]
+		suffixIsDigits := true
+		for _, r := range suffix {
+			if r < '0' || r > '9' {
+				suffixIsDigits = false
+				break
+			}
+		}
+		if suffixIsDigits {
+			return fmt.Errorf("trailing tilde and digits in path element")
+		}
+	}
+
+	return nil
+}
+
+// CheckFilePath checks that a slash-separated file path is valid.
+// The definition of a valid file path is the same as the definition
+// of a valid import path except that the set of allowed characters is larger:
+// all Unicode letters, ASCII digits, the ASCII space character (U+0020),
+// and the ASCII punctuation characters
+// “!#$%&()+,-.=@[]^_{}~”.
+// (The excluded punctuation characters, " * < > ? ` ' | / \ and :,
+// have special meanings in certain shells or operating systems.)
+//
+// CheckFilePath may be less restrictive in the future, but see the
+// top-level package documentation for additional information about
+// subtleties of Unicode.
+func CheckFilePath(path string) error {
+	if err := checkPath(path, filePath); err != nil {
+		return &InvalidPathError{Kind: "file", Path: path, Err: err}
+	}
+	return nil
+}
+
+// badWindowsNames are the reserved file path elements on Windows.
+// See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
+var badWindowsNames = []string{
+	"CON",
+	"PRN",
+	"AUX",
+	"NUL",
+	"COM1",
+	"COM2",
+	"COM3",
+	"COM4",
+	"COM5",
+	"COM6",
+	"COM7",
+	"COM8",
+	"COM9",
+	"LPT1",
+	"LPT2",
+	"LPT3",
+	"LPT4",
+	"LPT5",
+	"LPT6",
+	"LPT7",
+	"LPT8",
+	"LPT9",
+}
+
+// SplitPathVersion returns prefix and major version such that prefix+pathMajor == path
+// and version is either empty or "/vN" for N >= 2.
+// As a special case, gopkg.in paths are recognized directly;
+// they require ".vN" instead of "/vN", and for all N, not just N >= 2.
+// SplitPathVersion returns with ok = false when presented with
+// a path whose last path element does not satisfy the constraints
+// applied by CheckPath, such as "example.com/pkg/v1" or "example.com/pkg/v1.2".
+func SplitPathVersion(path string) (prefix, pathMajor string, ok bool) {
+	if strings.HasPrefix(path, "gopkg.in/") {
+		return splitGopkgIn(path)
+	}
+
+	i := len(path)
+	dot := false
+	for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9' || path[i-1] == '.') {
+		if path[i-1] == '.' {
+			dot = true
+		}
+		i--
+	}
+	if i <= 1 || i == len(path) || path[i-1] != 'v' || path[i-2] != '/' {
+		return path, "", true
+	}
+	prefix, pathMajor = path[:i-2], path[i-2:]
+	if dot || len(pathMajor) <= 2 || pathMajor[2] == '0' || pathMajor == "/v1" {
+		return path, "", false
+	}
+	return prefix, pathMajor, true
+}
+
+// splitGopkgIn is like SplitPathVersion but only for gopkg.in paths.
+func splitGopkgIn(path string) (prefix, pathMajor string, ok bool) {
+	if !strings.HasPrefix(path, "gopkg.in/") {
+		return path, "", false
+	}
+	i := len(path)
+	if strings.HasSuffix(path, "-unstable") {
+		i -= len("-unstable")
+	}
+	for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9') {
+		i--
+	}
+	if i <= 1 || path[i-1] != 'v' || path[i-2] != '.' {
+		// All gopkg.in paths must end in vN for some N.
+		return path, "", false
+	}
+	prefix, pathMajor = path[:i-2], path[i-2:]
+	if len(pathMajor) <= 2 || pathMajor[2] == '0' && pathMajor != ".v0" {
+		return path, "", false
+	}
+	return prefix, pathMajor, true
+}
+
+// MatchPathMajor reports whether the semantic version v
+// matches the path major version pathMajor.
+//
+// MatchPathMajor returns true if and only if CheckPathMajor returns nil.
+func MatchPathMajor(v, pathMajor string) bool {
+	return CheckPathMajor(v, pathMajor) == nil
+}
+
+// CheckPathMajor returns a non-nil error if the semantic version v
+// does not match the path major version pathMajor.
+func CheckPathMajor(v, pathMajor string) error {
+	// TODO(jayconrod): return errors or panic for invalid inputs. This function
+	// (and others) was covered by integration tests for cmd/go, and surrounding
+	// code protected against invalid inputs like non-canonical versions.
+	if strings.HasPrefix(pathMajor, ".v") && strings.HasSuffix(pathMajor, "-unstable") {
+		pathMajor = strings.TrimSuffix(pathMajor, "-unstable")
+	}
+	if strings.HasPrefix(v, "v0.0.0-") && pathMajor == ".v1" {
+		// Allow old bug in pseudo-versions that generated v0.0.0- pseudoversion for gopkg .v1.
+		// For example, gopkg.in/yaml.v2@v2.2.1's go.mod requires gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405.
+		return nil
+	}
+	m := semver.Major(v)
+	if pathMajor == "" {
+		if m == "v0" || m == "v1" || semver.Build(v) == "+incompatible" {
+			return nil
+		}
+		pathMajor = "v0 or v1"
+	} else if pathMajor[0] == '/' || pathMajor[0] == '.' {
+		if m == pathMajor[1:] {
+			return nil
+		}
+		pathMajor = pathMajor[1:]
+	}
+	return &InvalidVersionError{
+		Version: v,
+		Err:     fmt.Errorf("should be %s, not %s", pathMajor, semver.Major(v)),
+	}
+}
+
+// PathMajorPrefix returns the major-version tag prefix implied by pathMajor.
+// An empty PathMajorPrefix allows either v0 or v1.
+//
+// Note that MatchPathMajor may accept some versions that do not actually begin
+// with this prefix: namely, it accepts a 'v0.0.0-' prefix for a '.v1'
+// pathMajor, even though that pathMajor implies 'v1' tagging.
+func PathMajorPrefix(pathMajor string) string {
+	if pathMajor == "" {
+		return ""
+	}
+	if pathMajor[0] != '/' && pathMajor[0] != '.' {
+		panic("pathMajor suffix " + pathMajor + " passed to PathMajorPrefix lacks separator")
+	}
+	if strings.HasPrefix(pathMajor, ".v") && strings.HasSuffix(pathMajor, "-unstable") {
+		pathMajor = strings.TrimSuffix(pathMajor, "-unstable")
+	}
+	m := pathMajor[1:]
+	if m != semver.Major(m) {
+		panic("pathMajor suffix " + pathMajor + "passed to PathMajorPrefix is not a valid major version")
+	}
+	return m
+}
+
+// CanonicalVersion returns the canonical form of the version string v.
+// It is the same as semver.Canonical(v) except that it preserves the special build suffix "+incompatible".
+func CanonicalVersion(v string) string {
+	cv := semver.Canonical(v)
+	if semver.Build(v) == "+incompatible" {
+		cv += "+incompatible"
+	}
+	return cv
+}
+
+// Sort sorts the list by Path, breaking ties by comparing Version fields.
+// The Version fields are interpreted as semantic versions (using semver.Compare)
+// optionally followed by a tie-breaking suffix introduced by a slash character,
+// like in "v0.0.1/go.mod".
+func Sort(list []Version) {
+	sort.Slice(list, func(i, j int) bool {
+		mi := list[i]
+		mj := list[j]
+		if mi.Path != mj.Path {
+			return mi.Path < mj.Path
+		}
+		// To help go.sum formatting, allow version/file.
+		// Compare semver prefix by semver rules,
+		// file by string order.
+		vi := mi.Version
+		vj := mj.Version
+		var fi, fj string
+		if k := strings.Index(vi, "/"); k >= 0 {
+			vi, fi = vi[:k], vi[k:]
+		}
+		if k := strings.Index(vj, "/"); k >= 0 {
+			vj, fj = vj[:k], vj[k:]
+		}
+		if vi != vj {
+			return semver.Compare(vi, vj) < 0
+		}
+		return fi < fj
+	})
+}
+
+// EscapePath returns the escaped form of the given module path.
+// It fails if the module path is invalid.
+func EscapePath(path string) (escaped string, err error) {
+	if err := CheckPath(path); err != nil {
+		return "", err
+	}
+
+	return escapeString(path)
+}
+
+// EscapeVersion returns the escaped form of the given module version.
+// Versions are allowed to be in non-semver form but must be valid file names
+// and not contain exclamation marks.
+func EscapeVersion(v string) (escaped string, err error) {
+	if err := checkElem(v, filePath); err != nil || strings.Contains(v, "!") {
+		return "", &InvalidVersionError{
+			Version: v,
+			Err:     fmt.Errorf("disallowed version string"),
+		}
+	}
+	return escapeString(v)
+}
+
+func escapeString(s string) (escaped string, err error) {
+	haveUpper := false
+	for _, r := range s {
+		if r == '!' || r >= utf8.RuneSelf {
+			// This should be disallowed by CheckPath, but diagnose anyway.
+			// The correctness of the escaping loop below depends on it.
+			return "", fmt.Errorf("internal error: inconsistency in EscapePath")
+		}
+		if 'A' <= r && r <= 'Z' {
+			haveUpper = true
+		}
+	}
+
+	if !haveUpper {
+		return s, nil
+	}
+
+	var buf []byte
+	for _, r := range s {
+		if 'A' <= r && r <= 'Z' {
+			buf = append(buf, '!', byte(r+'a'-'A'))
+		} else {
+			buf = append(buf, byte(r))
+		}
+	}
+	return string(buf), nil
+}
+
+// UnescapePath returns the module path for the given escaped path.
+// It fails if the escaped path is invalid or describes an invalid path.
+func UnescapePath(escaped string) (path string, err error) {
+	path, ok := unescapeString(escaped)
+	if !ok {
+		return "", fmt.Errorf("invalid escaped module path %q", escaped)
+	}
+	if err := CheckPath(path); err != nil {
+		return "", fmt.Errorf("invalid escaped module path %q: %v", escaped, err)
+	}
+	return path, nil
+}
+
+// UnescapeVersion returns the version string for the given escaped version.
+// It fails if the escaped form is invalid or describes an invalid version.
+// Versions are allowed to be in non-semver form but must be valid file names
+// and not contain exclamation marks.
+func UnescapeVersion(escaped string) (v string, err error) {
+	v, ok := unescapeString(escaped)
+	if !ok {
+		return "", fmt.Errorf("invalid escaped version %q", escaped)
+	}
+	if err := checkElem(v, filePath); err != nil {
+		return "", fmt.Errorf("invalid escaped version %q: %v", v, err)
+	}
+	return v, nil
+}
+
+func unescapeString(escaped string) (string, bool) {
+	var buf []byte
+
+	bang := false
+	for _, r := range escaped {
+		if r >= utf8.RuneSelf {
+			return "", false
+		}
+		if bang {
+			bang = false
+			if r < 'a' || 'z' < r {
+				return "", false
+			}
+			buf = append(buf, byte(r+'A'-'a'))
+			continue
+		}
+		if r == '!' {
+			bang = true
+			continue
+		}
+		if 'A' <= r && r <= 'Z' {
+			return "", false
+		}
+		buf = append(buf, byte(r))
+	}
+	if bang {
+		return "", false
+	}
+	return string(buf), true
+}
+
+// MatchPrefixPatterns reports whether any path prefix of target matches one of
+// the glob patterns (as defined by path.Match) in the comma-separated globs
+// list. This implements the algorithm used when matching a module path to the
+// GOPRIVATE environment variable, as described by 'go help module-private'.
+//
+// It ignores any empty or malformed patterns in the list.
+// Trailing slashes on patterns are ignored.
+func MatchPrefixPatterns(globs, target string) bool {
+	for globs != "" {
+		// Extract next non-empty glob in comma-separated list.
+		var glob string
+		if i := strings.Index(globs, ","); i >= 0 {
+			glob, globs = globs[:i], globs[i+1:]
+		} else {
+			glob, globs = globs, ""
+		}
+		glob = strings.TrimSuffix(glob, "/")
+		if glob == "" {
+			continue
+		}
+
+		// A glob with N+1 path elements (N slashes) needs to be matched
+		// against the first N+1 path elements of target,
+		// which end just before the N+1'th slash.
+		n := strings.Count(glob, "/")
+		prefix := target
+		// Walk target, counting slashes, truncating at the N+1'th slash.
+		for i := 0; i < len(target); i++ {
+			if target[i] == '/' {
+				if n == 0 {
+					prefix = target[:i]
+					break
+				}
+				n--
+			}
+		}
+		if n > 0 {
+			// Not enough prefix elements.
+			continue
+		}
+		matched, _ := path.Match(glob, prefix)
+		if matched {
+			return true
+		}
+	}
+	return false
+}

vendor/golang.org/x/mod/module/pseudo.go

@@ -0,0 +1,250 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Pseudo-versions
+//
+// Code authors are expected to tag the revisions they want users to use,
+// including prereleases. However, not all authors tag versions at all,
+// and not all commits a user might want to try will have tags.
+// A pseudo-version is a version with a special form that allows us to
+// address an untagged commit and order that version with respect to
+// other versions we might encounter.
+//
+// A pseudo-version takes one of the general forms:
+//
+//	(1) vX.0.0-yyyymmddhhmmss-abcdef123456
+//	(2) vX.Y.(Z+1)-0.yyyymmddhhmmss-abcdef123456
+//	(3) vX.Y.(Z+1)-0.yyyymmddhhmmss-abcdef123456+incompatible
+//	(4) vX.Y.Z-pre.0.yyyymmddhhmmss-abcdef123456
+//	(5) vX.Y.Z-pre.0.yyyymmddhhmmss-abcdef123456+incompatible
+//
+// If there is no recently tagged version with the right major version vX,
+// then form (1) is used, creating a space of pseudo-versions at the bottom
+// of the vX version range, less than any tagged version, including the unlikely v0.0.0.
+//
+// If the most recent tagged version before the target commit is vX.Y.Z or vX.Y.Z+incompatible,
+// then the pseudo-version uses form (2) or (3), making it a prerelease for the next
+// possible semantic version after vX.Y.Z. The leading 0 segment in the prerelease string
+// ensures that the pseudo-version compares less than possible future explicit prereleases
+// like vX.Y.(Z+1)-rc1 or vX.Y.(Z+1)-1.
+//
+// If the most recent tagged version before the target commit is vX.Y.Z-pre or vX.Y.Z-pre+incompatible,
+// then the pseudo-version uses form (4) or (5), making it a slightly later prerelease.
+
+package module
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"golang.org/x/mod/internal/lazyregexp"
+	"golang.org/x/mod/semver"
+)
+
+var pseudoVersionRE = lazyregexp.New(`^v[0-9]+\.(0\.0-|\d+\.\d+-([^+]*\.)?0\.)\d{14}-[A-Za-z0-9]+(\+[0-9A-Za-z-]+(\.[0-9A-Za-z-]+)*)?$`)
+
+const PseudoVersionTimestampFormat = "20060102150405"
+
+// PseudoVersion returns a pseudo-version for the given major version ("v1")
+// preexisting older tagged version ("" or "v1.2.3" or "v1.2.3-pre"), revision time,
+// and revision identifier (usually a 12-byte commit hash prefix).
+func PseudoVersion(major, older string, t time.Time, rev string) string {
+	if major == "" {
+		major = "v0"
+	}
+	segment := fmt.Sprintf("%s-%s", t.UTC().Format(PseudoVersionTimestampFormat), rev)
+	build := semver.Build(older)
+	older = semver.Canonical(older)
+	if older == "" {
+		return major + ".0.0-" + segment // form (1)
+	}
+	if semver.Prerelease(older) != "" {
+		return older + ".0." + segment + build // form (4), (5)
+	}
+
+	// Form (2), (3).
+	// Extract patch from vMAJOR.MINOR.PATCH
+	i := strings.LastIndex(older, ".") + 1
+	v, patch := older[:i], older[i:]
+
+	// Reassemble.
+	return v + incDecimal(patch) + "-0." + segment + build
+}
+
+// ZeroPseudoVersion returns a pseudo-version with a zero timestamp and
+// revision, which may be used as a placeholder.
+func ZeroPseudoVersion(major string) string {
+	return PseudoVersion(major, "", time.Time{}, "000000000000")
+}
+
+// incDecimal returns the decimal string incremented by 1.
+func incDecimal(decimal string) string {
+	// Scan right to left turning 9s to 0s until you find a digit to increment.
+	digits := []byte(decimal)
+	i := len(digits) - 1
+	for ; i >= 0 && digits[i] == '9'; i-- {
+		digits[i] = '0'
+	}
+	if i >= 0 {
+		digits[i]++
+	} else {
+		// digits is all zeros
+		digits[0] = '1'
+		digits = append(digits, '0')
+	}
+	return string(digits)
+}
+
+// decDecimal returns the decimal string decremented by 1, or the empty string
+// if the decimal is all zeroes.
+func decDecimal(decimal string) string {
+	// Scan right to left turning 0s to 9s until you find a digit to decrement.
+	digits := []byte(decimal)
+	i := len(digits) - 1
+	for ; i >= 0 && digits[i] == '0'; i-- {
+		digits[i] = '9'
+	}
+	if i < 0 {
+		// decimal is all zeros
+		return ""
+	}
+	if i == 0 && digits[i] == '1' && len(digits) > 1 {
+		digits = digits[1:]
+	} else {
+		digits[i]--
+	}
+	return string(digits)
+}
+
+// IsPseudoVersion reports whether v is a pseudo-version.
+func IsPseudoVersion(v string) bool {
+	return strings.Count(v, "-") >= 2 && semver.IsValid(v) && pseudoVersionRE.MatchString(v)
+}
+
+// IsZeroPseudoVersion returns whether v is a pseudo-version with a zero base,
+// timestamp, and revision, as returned by ZeroPseudoVersion.
+func IsZeroPseudoVersion(v string) bool {
+	return v == ZeroPseudoVersion(semver.Major(v))
+}
+
+// PseudoVersionTime returns the time stamp of the pseudo-version v.
+// It returns an error if v is not a pseudo-version or if the time stamp
+// embedded in the pseudo-version is not a valid time.
+func PseudoVersionTime(v string) (time.Time, error) {
+	_, timestamp, _, _, err := parsePseudoVersion(v)
+	if err != nil {
+		return time.Time{}, err
+	}
+	t, err := time.Parse("20060102150405", timestamp)
+	if err != nil {
+		return time.Time{}, &InvalidVersionError{
+			Version: v,
+			Pseudo:  true,
+			Err:     fmt.Errorf("malformed time %q", timestamp),
+		}
+	}
+	return t, nil
+}
+
+// PseudoVersionRev returns the revision identifier of the pseudo-version v.
+// It returns an error if v is not a pseudo-version.
+func PseudoVersionRev(v string) (rev string, err error) {
+	_, _, rev, _, err = parsePseudoVersion(v)
+	return
+}
+
+// PseudoVersionBase returns the canonical parent version, if any, upon which
+// the pseudo-version v is based.
+//
+// If v has no parent version (that is, if it is "vX.0.0-[…]"),
+// PseudoVersionBase returns the empty string and a nil error.
+func PseudoVersionBase(v string) (string, error) {
+	base, _, _, build, err := parsePseudoVersion(v)
+	if err != nil {
+		return "", err
+	}
+
+	switch pre := semver.Prerelease(base); pre {
+	case "":
+		// vX.0.0-yyyymmddhhmmss-abcdef123456 → ""
+		if build != "" {
+			// Pseudo-versions of the form vX.0.0-yyyymmddhhmmss-abcdef123456+incompatible
+			// are nonsensical: the "vX.0.0-" prefix implies that there is no parent tag,
+			// but the "+incompatible" suffix implies that the major version of
+			// the parent tag is not compatible with the module's import path.
+			//
+			// There are a few such entries in the index generated by proxy.golang.org,
+			// but we believe those entries were generated by the proxy itself.
+			return "", &InvalidVersionError{
+				Version: v,
+				Pseudo:  true,
+				Err:     fmt.Errorf("lacks base version, but has build metadata %q", build),
+			}
+		}
+		return "", nil
+
+	case "-0":
+		// vX.Y.(Z+1)-0.yyyymmddhhmmss-abcdef123456 → vX.Y.Z
+		// vX.Y.(Z+1)-0.yyyymmddhhmmss-abcdef123456+incompatible → vX.Y.Z+incompatible
+		base = strings.TrimSuffix(base, pre)
+		i := strings.LastIndexByte(base, '.')
+		if i < 0 {
+			panic("base from parsePseudoVersion missing patch number: " + base)
+		}
+		patch := decDecimal(base[i+1:])
+		if patch == "" {
+			// vX.0.0-0 is invalid, but has been observed in the wild in the index
+			// generated by requests to proxy.golang.org.
+			//
+			// NOTE(bcmills): I cannot find a historical bug that accounts for
+			// pseudo-versions of this form, nor have I seen such versions in any
+			// actual go.mod files. If we find actual examples of this form and a
+			// reasonable theory of how they came into existence, it seems fine to
+			// treat them as equivalent to vX.0.0 (especially since the invalid
+			// pseudo-versions have lower precedence than the real ones). For now, we
+			// reject them.
+			return "", &InvalidVersionError{
+				Version: v,
+				Pseudo:  true,
+				Err:     fmt.Errorf("version before %s would have negative patch number", base),
+			}
+		}
+		return base[:i+1] + patch + build, nil
+
+	default:
+		// vX.Y.Z-pre.0.yyyymmddhhmmss-abcdef123456 → vX.Y.Z-pre
+		// vX.Y.Z-pre.0.yyyymmddhhmmss-abcdef123456+incompatible → vX.Y.Z-pre+incompatible
+		if !strings.HasSuffix(base, ".0") {
+			panic(`base from parsePseudoVersion missing ".0" before date: ` + base)
+		}
+		return strings.TrimSuffix(base, ".0") + build, nil
+	}
+}
+
+var errPseudoSyntax = errors.New("syntax error")
+
+func parsePseudoVersion(v string) (base, timestamp, rev, build string, err error) {
+	if !IsPseudoVersion(v) {
+		return "", "", "", "", &InvalidVersionError{
+			Version: v,
+			Pseudo:  true,
+			Err:     errPseudoSyntax,
+		}
+	}
+	build = semver.Build(v)
+	v = strings.TrimSuffix(v, build)
+	j := strings.LastIndex(v, "-")
+	v, rev = v[:j], v[j+1:]
+	i := strings.LastIndex(v, "-")
+	if j := strings.LastIndex(v, "."); j > i {
+		base = v[:j] // "vX.Y.Z-pre.0" or "vX.Y.(Z+1)-0"
+		timestamp = v[j+1:]
+	} else {
+		base = v[:i] // "vX.0.0"
+		timestamp = v[i+1:]
+	}
+	return base, timestamp, rev, build, nil
+}

vendor/gopkg.in/yaml.v3/LICENSE

@@ -0,0 +1,50 @@
+
+This project is covered by two different licenses: MIT and Apache.
+
+#### MIT License ####
+
+The following files were ported to Go from C files of libyaml, and thus
+are still covered by their original MIT license, with the additional
+copyright staring in 2011 when the project was ported over:
+
+    apic.go emitterc.go parserc.go readerc.go scannerc.go
+    writerc.go yamlh.go yamlprivateh.go
+
+Copyright (c) 2006-2010 Kirill Simonov
+Copyright (c) 2006-2011 Kirill Simonov
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+### Apache License ###
+
+All the remaining project files are covered by the Apache license:
+
+Copyright (c) 2011-2019 Canonical Ltd
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/gopkg.in/yaml.v3/NOTICE

@@ -0,0 +1,13 @@
+Copyright 2011-2016 Canonical Ltd.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/gopkg.in/yaml.v3/README.md

@@ -0,0 +1,150 @@
+# YAML support for the Go language
+
+Introduction
+------------
+
+The yaml package enables Go programs to comfortably encode and decode YAML
+values. It was developed within [Canonical](https://www.canonical.com) as
+part of the [juju](https://juju.ubuntu.com) project, and is based on a
+pure Go port of the well-known [libyaml](http://pyyaml.org/wiki/LibYAML)
+C library to parse and generate YAML data quickly and reliably.
+
+Compatibility
+-------------
+
+The yaml package supports most of YAML 1.2, but preserves some behavior
+from 1.1 for backwards compatibility.
+
+Specifically, as of v3 of the yaml package:
+
+ - YAML 1.1 bools (_yes/no, on/off_) are supported as long as they are being
+   decoded into a typed bool value. Otherwise they behave as a string. Booleans
+   in YAML 1.2 are _true/false_ only.
+ - Octals encode and decode as _0777_ per YAML 1.1, rather than _0o777_
+   as specified in YAML 1.2, because most parsers still use the old format.
+   Octals in the  _0o777_ format are supported though, so new files work.
+ - Does not support base-60 floats. These are gone from YAML 1.2, and were
+   actually never supported by this package as it's clearly a poor choice.
+
+and offers backwards
+compatibility with YAML 1.1 in some cases.
+1.2, including support for
+anchors, tags, map merging, etc. Multi-document unmarshalling is not yet
+implemented, and base-60 floats from YAML 1.1 are purposefully not
+supported since they're a poor design and are gone in YAML 1.2.
+
+Installation and usage
+----------------------
+
+The import path for the package is *gopkg.in/yaml.v3*.
+
+To install it, run:
+
+    go get gopkg.in/yaml.v3
+
+API documentation
+-----------------
+
+If opened in a browser, the import path itself leads to the API documentation:
+
+  - [https://gopkg.in/yaml.v3](https://gopkg.in/yaml.v3)
+
+API stability
+-------------
+
+The package API for yaml v3 will remain stable as described in [gopkg.in](https://gopkg.in).
+
+
+License
+-------
+
+The yaml package is licensed under the MIT and Apache License 2.0 licenses.
+Please see the LICENSE file for details.
+
+
+Example
+-------
+
+```Go
+package main
+
+import (
+        "fmt"
+        "log"
+
+        "gopkg.in/yaml.v3"
+)
+
+var data = `
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+`
+
+// Note: struct fields must be public in order for unmarshal to
+// correctly populate the data.
+type T struct {
+        A string
+        B struct {
+                RenamedC int   `yaml:"c"`
+                D        []int `yaml:",flow"`
+        }
+}
+
+func main() {
+        t := T{}
+    
+        err := yaml.Unmarshal([]byte(data), &t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t:\n%v\n\n", t)
+    
+        d, err := yaml.Marshal(&t)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- t dump:\n%s\n\n", string(d))
+    
+        m := make(map[interface{}]interface{})
+    
+        err = yaml.Unmarshal([]byte(data), &m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m:\n%v\n\n", m)
+    
+        d, err = yaml.Marshal(&m)
+        if err != nil {
+                log.Fatalf("error: %v", err)
+        }
+        fmt.Printf("--- m dump:\n%s\n\n", string(d))
+}
+```
+
+This example will generate the following output:
+
+```
+--- t:
+{Easy! {2 [3 4]}}
+
+--- t dump:
+a: Easy!
+b:
+  c: 2
+  d: [3, 4]
+
+
+--- m:
+map[a:Easy! b:map[c:2 d:[3 4]]]
+
+--- m dump:
+a: Easy!
+b:
+  c: 2
+  d:
+  - 3
+  - 4
+```
+

vendor/gopkg.in/yaml.v3/apic.go

@@ -0,0 +1,747 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+import (
+	"io"
+)
+
+func yaml_insert_token(parser *yaml_parser_t, pos int, token *yaml_token_t) {
+	//fmt.Println("yaml_insert_token", "pos:", pos, "typ:", token.typ, "head:", parser.tokens_head, "len:", len(parser.tokens))
+
+	// Check if we can move the queue at the beginning of the buffer.
+	if parser.tokens_head > 0 && len(parser.tokens) == cap(parser.tokens) {
+		if parser.tokens_head != len(parser.tokens) {
+			copy(parser.tokens, parser.tokens[parser.tokens_head:])
+		}
+		parser.tokens = parser.tokens[:len(parser.tokens)-parser.tokens_head]
+		parser.tokens_head = 0
+	}
+	parser.tokens = append(parser.tokens, *token)
+	if pos < 0 {
+		return
+	}
+	copy(parser.tokens[parser.tokens_head+pos+1:], parser.tokens[parser.tokens_head+pos:])
+	parser.tokens[parser.tokens_head+pos] = *token
+}
+
+// Create a new parser object.
+func yaml_parser_initialize(parser *yaml_parser_t) bool {
+	*parser = yaml_parser_t{
+		raw_buffer: make([]byte, 0, input_raw_buffer_size),
+		buffer:     make([]byte, 0, input_buffer_size),
+	}
+	return true
+}
+
+// Destroy a parser object.
+func yaml_parser_delete(parser *yaml_parser_t) {
+	*parser = yaml_parser_t{}
+}
+
+// String read handler.
+func yaml_string_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	if parser.input_pos == len(parser.input) {
+		return 0, io.EOF
+	}
+	n = copy(buffer, parser.input[parser.input_pos:])
+	parser.input_pos += n
+	return n, nil
+}
+
+// Reader read handler.
+func yaml_reader_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
+	return parser.input_reader.Read(buffer)
+}
+
+// Set a string input.
+func yaml_parser_set_input_string(parser *yaml_parser_t, input []byte) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_string_read_handler
+	parser.input = input
+	parser.input_pos = 0
+}
+
+// Set a file input.
+func yaml_parser_set_input_reader(parser *yaml_parser_t, r io.Reader) {
+	if parser.read_handler != nil {
+		panic("must set the input source only once")
+	}
+	parser.read_handler = yaml_reader_read_handler
+	parser.input_reader = r
+}
+
+// Set the source encoding.
+func yaml_parser_set_encoding(parser *yaml_parser_t, encoding yaml_encoding_t) {
+	if parser.encoding != yaml_ANY_ENCODING {
+		panic("must set the encoding only once")
+	}
+	parser.encoding = encoding
+}
+
+// Create a new emitter object.
+func yaml_emitter_initialize(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{
+		buffer:     make([]byte, output_buffer_size),
+		raw_buffer: make([]byte, 0, output_raw_buffer_size),
+		states:     make([]yaml_emitter_state_t, 0, initial_stack_size),
+		events:     make([]yaml_event_t, 0, initial_queue_size),
+		best_width: -1,
+	}
+}
+
+// Destroy an emitter object.
+func yaml_emitter_delete(emitter *yaml_emitter_t) {
+	*emitter = yaml_emitter_t{}
+}
+
+// String write handler.
+func yaml_string_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	*emitter.output_buffer = append(*emitter.output_buffer, buffer...)
+	return nil
+}
+
+// yaml_writer_write_handler uses emitter.output_writer to write the
+// emitted text.
+func yaml_writer_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
+	_, err := emitter.output_writer.Write(buffer)
+	return err
+}
+
+// Set a string output.
+func yaml_emitter_set_output_string(emitter *yaml_emitter_t, output_buffer *[]byte) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_string_write_handler
+	emitter.output_buffer = output_buffer
+}
+
+// Set a file output.
+func yaml_emitter_set_output_writer(emitter *yaml_emitter_t, w io.Writer) {
+	if emitter.write_handler != nil {
+		panic("must set the output target only once")
+	}
+	emitter.write_handler = yaml_writer_write_handler
+	emitter.output_writer = w
+}
+
+// Set the output encoding.
+func yaml_emitter_set_encoding(emitter *yaml_emitter_t, encoding yaml_encoding_t) {
+	if emitter.encoding != yaml_ANY_ENCODING {
+		panic("must set the output encoding only once")
+	}
+	emitter.encoding = encoding
+}
+
+// Set the canonical output style.
+func yaml_emitter_set_canonical(emitter *yaml_emitter_t, canonical bool) {
+	emitter.canonical = canonical
+}
+
+// Set the indentation increment.
+func yaml_emitter_set_indent(emitter *yaml_emitter_t, indent int) {
+	if indent < 2 || indent > 9 {
+		indent = 2
+	}
+	emitter.best_indent = indent
+}
+
+// Set the preferred line width.
+func yaml_emitter_set_width(emitter *yaml_emitter_t, width int) {
+	if width < 0 {
+		width = -1
+	}
+	emitter.best_width = width
+}
+
+// Set if unescaped non-ASCII characters are allowed.
+func yaml_emitter_set_unicode(emitter *yaml_emitter_t, unicode bool) {
+	emitter.unicode = unicode
+}
+
+// Set the preferred line break character.
+func yaml_emitter_set_break(emitter *yaml_emitter_t, line_break yaml_break_t) {
+	emitter.line_break = line_break
+}
+
+///*
+// * Destroy a token object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_token_delete(yaml_token_t *token)
+//{
+//    assert(token);  // Non-NULL token object expected.
+//
+//    switch (token.type)
+//    {
+//        case YAML_TAG_DIRECTIVE_TOKEN:
+//            yaml_free(token.data.tag_directive.handle);
+//            yaml_free(token.data.tag_directive.prefix);
+//            break;
+//
+//        case YAML_ALIAS_TOKEN:
+//            yaml_free(token.data.alias.value);
+//            break;
+//
+//        case YAML_ANCHOR_TOKEN:
+//            yaml_free(token.data.anchor.value);
+//            break;
+//
+//        case YAML_TAG_TOKEN:
+//            yaml_free(token.data.tag.handle);
+//            yaml_free(token.data.tag.suffix);
+//            break;
+//
+//        case YAML_SCALAR_TOKEN:
+//            yaml_free(token.data.scalar.value);
+//            break;
+//
+//        default:
+//            break;
+//    }
+//
+//    memset(token, 0, sizeof(yaml_token_t));
+//}
+//
+///*
+// * Check if a string is a valid UTF-8 sequence.
+// *
+// * Check 'reader.c' for more details on UTF-8 encoding.
+// */
+//
+//static int
+//yaml_check_utf8(yaml_char_t *start, size_t length)
+//{
+//    yaml_char_t *end = start+length;
+//    yaml_char_t *pointer = start;
+//
+//    while (pointer < end) {
+//        unsigned char octet;
+//        unsigned int width;
+//        unsigned int value;
+//        size_t k;
+//
+//        octet = pointer[0];
+//        width = (octet & 0x80) == 0x00 ? 1 :
+//                (octet & 0xE0) == 0xC0 ? 2 :
+//                (octet & 0xF0) == 0xE0 ? 3 :
+//                (octet & 0xF8) == 0xF0 ? 4 : 0;
+//        value = (octet & 0x80) == 0x00 ? octet & 0x7F :
+//                (octet & 0xE0) == 0xC0 ? octet & 0x1F :
+//                (octet & 0xF0) == 0xE0 ? octet & 0x0F :
+//                (octet & 0xF8) == 0xF0 ? octet & 0x07 : 0;
+//        if (!width) return 0;
+//        if (pointer+width > end) return 0;
+//        for (k = 1; k < width; k ++) {
+//            octet = pointer[k];
+//            if ((octet & 0xC0) != 0x80) return 0;
+//            value = (value << 6) + (octet & 0x3F);
+//        }
+//        if (!((width == 1) ||
+//            (width == 2 && value >= 0x80) ||
+//            (width == 3 && value >= 0x800) ||
+//            (width == 4 && value >= 0x10000))) return 0;
+//
+//        pointer += width;
+//    }
+//
+//    return 1;
+//}
+//
+
+// Create STREAM-START.
+func yaml_stream_start_event_initialize(event *yaml_event_t, encoding yaml_encoding_t) {
+	*event = yaml_event_t{
+		typ:      yaml_STREAM_START_EVENT,
+		encoding: encoding,
+	}
+}
+
+// Create STREAM-END.
+func yaml_stream_end_event_initialize(event *yaml_event_t) {
+	*event = yaml_event_t{
+		typ: yaml_STREAM_END_EVENT,
+	}
+}
+
+// Create DOCUMENT-START.
+func yaml_document_start_event_initialize(
+	event *yaml_event_t,
+	version_directive *yaml_version_directive_t,
+	tag_directives []yaml_tag_directive_t,
+	implicit bool,
+) {
+	*event = yaml_event_t{
+		typ:               yaml_DOCUMENT_START_EVENT,
+		version_directive: version_directive,
+		tag_directives:    tag_directives,
+		implicit:          implicit,
+	}
+}
+
+// Create DOCUMENT-END.
+func yaml_document_end_event_initialize(event *yaml_event_t, implicit bool) {
+	*event = yaml_event_t{
+		typ:      yaml_DOCUMENT_END_EVENT,
+		implicit: implicit,
+	}
+}
+
+// Create ALIAS.
+func yaml_alias_event_initialize(event *yaml_event_t, anchor []byte) bool {
+	*event = yaml_event_t{
+		typ:    yaml_ALIAS_EVENT,
+		anchor: anchor,
+	}
+	return true
+}
+
+// Create SCALAR.
+func yaml_scalar_event_initialize(event *yaml_event_t, anchor, tag, value []byte, plain_implicit, quoted_implicit bool, style yaml_scalar_style_t) bool {
+	*event = yaml_event_t{
+		typ:             yaml_SCALAR_EVENT,
+		anchor:          anchor,
+		tag:             tag,
+		value:           value,
+		implicit:        plain_implicit,
+		quoted_implicit: quoted_implicit,
+		style:           yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-START.
+func yaml_sequence_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_sequence_style_t) bool {
+	*event = yaml_event_t{
+		typ:      yaml_SEQUENCE_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+	return true
+}
+
+// Create SEQUENCE-END.
+func yaml_sequence_end_event_initialize(event *yaml_event_t) bool {
+	*event = yaml_event_t{
+		typ: yaml_SEQUENCE_END_EVENT,
+	}
+	return true
+}
+
+// Create MAPPING-START.
+func yaml_mapping_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_mapping_style_t) {
+	*event = yaml_event_t{
+		typ:      yaml_MAPPING_START_EVENT,
+		anchor:   anchor,
+		tag:      tag,
+		implicit: implicit,
+		style:    yaml_style_t(style),
+	}
+}
+
+// Create MAPPING-END.
+func yaml_mapping_end_event_initialize(event *yaml_event_t) {
+	*event = yaml_event_t{
+		typ: yaml_MAPPING_END_EVENT,
+	}
+}
+
+// Destroy an event object.
+func yaml_event_delete(event *yaml_event_t) {
+	*event = yaml_event_t{}
+}
+
+///*
+// * Create a document object.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_initialize(document *yaml_document_t,
+//        version_directive *yaml_version_directive_t,
+//        tag_directives_start *yaml_tag_directive_t,
+//        tag_directives_end *yaml_tag_directive_t,
+//        start_implicit int, end_implicit int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    struct {
+//        start *yaml_node_t
+//        end *yaml_node_t
+//        top *yaml_node_t
+//    } nodes = { NULL, NULL, NULL }
+//    version_directive_copy *yaml_version_directive_t = NULL
+//    struct {
+//        start *yaml_tag_directive_t
+//        end *yaml_tag_directive_t
+//        top *yaml_tag_directive_t
+//    } tag_directives_copy = { NULL, NULL, NULL }
+//    value yaml_tag_directive_t = { NULL, NULL }
+//    mark yaml_mark_t = { 0, 0, 0 }
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert((tag_directives_start && tag_directives_end) ||
+//            (tag_directives_start == tag_directives_end))
+//                            // Valid tag directives are expected.
+//
+//    if (!STACK_INIT(&context, nodes, INITIAL_STACK_SIZE)) goto error
+//
+//    if (version_directive) {
+//        version_directive_copy = yaml_malloc(sizeof(yaml_version_directive_t))
+//        if (!version_directive_copy) goto error
+//        version_directive_copy.major = version_directive.major
+//        version_directive_copy.minor = version_directive.minor
+//    }
+//
+//    if (tag_directives_start != tag_directives_end) {
+//        tag_directive *yaml_tag_directive_t
+//        if (!STACK_INIT(&context, tag_directives_copy, INITIAL_STACK_SIZE))
+//            goto error
+//        for (tag_directive = tag_directives_start
+//                tag_directive != tag_directives_end; tag_directive ++) {
+//            assert(tag_directive.handle)
+//            assert(tag_directive.prefix)
+//            if (!yaml_check_utf8(tag_directive.handle,
+//                        strlen((char *)tag_directive.handle)))
+//                goto error
+//            if (!yaml_check_utf8(tag_directive.prefix,
+//                        strlen((char *)tag_directive.prefix)))
+//                goto error
+//            value.handle = yaml_strdup(tag_directive.handle)
+//            value.prefix = yaml_strdup(tag_directive.prefix)
+//            if (!value.handle || !value.prefix) goto error
+//            if (!PUSH(&context, tag_directives_copy, value))
+//                goto error
+//            value.handle = NULL
+//            value.prefix = NULL
+//        }
+//    }
+//
+//    DOCUMENT_INIT(*document, nodes.start, nodes.end, version_directive_copy,
+//            tag_directives_copy.start, tag_directives_copy.top,
+//            start_implicit, end_implicit, mark, mark)
+//
+//    return 1
+//
+//error:
+//    STACK_DEL(&context, nodes)
+//    yaml_free(version_directive_copy)
+//    while (!STACK_EMPTY(&context, tag_directives_copy)) {
+//        value yaml_tag_directive_t = POP(&context, tag_directives_copy)
+//        yaml_free(value.handle)
+//        yaml_free(value.prefix)
+//    }
+//    STACK_DEL(&context, tag_directives_copy)
+//    yaml_free(value.handle)
+//    yaml_free(value.prefix)
+//
+//    return 0
+//}
+//
+///*
+// * Destroy a document object.
+// */
+//
+//YAML_DECLARE(void)
+//yaml_document_delete(document *yaml_document_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    tag_directive *yaml_tag_directive_t
+//
+//    context.error = YAML_NO_ERROR // Eliminate a compiler warning.
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    while (!STACK_EMPTY(&context, document.nodes)) {
+//        node yaml_node_t = POP(&context, document.nodes)
+//        yaml_free(node.tag)
+//        switch (node.type) {
+//            case YAML_SCALAR_NODE:
+//                yaml_free(node.data.scalar.value)
+//                break
+//            case YAML_SEQUENCE_NODE:
+//                STACK_DEL(&context, node.data.sequence.items)
+//                break
+//            case YAML_MAPPING_NODE:
+//                STACK_DEL(&context, node.data.mapping.pairs)
+//                break
+//            default:
+//                assert(0) // Should not happen.
+//        }
+//    }
+//    STACK_DEL(&context, document.nodes)
+//
+//    yaml_free(document.version_directive)
+//    for (tag_directive = document.tag_directives.start
+//            tag_directive != document.tag_directives.end
+//            tag_directive++) {
+//        yaml_free(tag_directive.handle)
+//        yaml_free(tag_directive.prefix)
+//    }
+//    yaml_free(document.tag_directives.start)
+//
+//    memset(document, 0, sizeof(yaml_document_t))
+//}
+//
+///**
+// * Get a document node.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_node(document *yaml_document_t, index int)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (index > 0 && document.nodes.start + index <= document.nodes.top) {
+//        return document.nodes.start + index - 1
+//    }
+//    return NULL
+//}
+//
+///**
+// * Get the root object.
+// */
+//
+//YAML_DECLARE(yaml_node_t *)
+//yaml_document_get_root_node(document *yaml_document_t)
+//{
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (document.nodes.top != document.nodes.start) {
+//        return document.nodes.start
+//    }
+//    return NULL
+//}
+//
+///*
+// * Add a scalar node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_scalar(document *yaml_document_t,
+//        tag *yaml_char_t, value *yaml_char_t, length int,
+//        style yaml_scalar_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    value_copy *yaml_char_t = NULL
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//    assert(value) // Non-NULL value is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SCALAR_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (length < 0) {
+//        length = strlen((char *)value)
+//    }
+//
+//    if (!yaml_check_utf8(value, length)) goto error
+//    value_copy = yaml_malloc(length+1)
+//    if (!value_copy) goto error
+//    memcpy(value_copy, value, length)
+//    value_copy[length] = '\0'
+//
+//    SCALAR_NODE_INIT(node, tag_copy, value_copy, length, style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    yaml_free(tag_copy)
+//    yaml_free(value_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a sequence node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_sequence(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_sequence_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_item_t
+//        end *yaml_node_item_t
+//        top *yaml_node_item_t
+//    } items = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, items, INITIAL_STACK_SIZE)) goto error
+//
+//    SEQUENCE_NODE_INIT(node, tag_copy, items.start, items.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, items)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Add a mapping node to a document.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_add_mapping(document *yaml_document_t,
+//        tag *yaml_char_t, style yaml_mapping_style_t)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//    mark yaml_mark_t = { 0, 0, 0 }
+//    tag_copy *yaml_char_t = NULL
+//    struct {
+//        start *yaml_node_pair_t
+//        end *yaml_node_pair_t
+//        top *yaml_node_pair_t
+//    } pairs = { NULL, NULL, NULL }
+//    node yaml_node_t
+//
+//    assert(document) // Non-NULL document object is expected.
+//
+//    if (!tag) {
+//        tag = (yaml_char_t *)YAML_DEFAULT_MAPPING_TAG
+//    }
+//
+//    if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
+//    tag_copy = yaml_strdup(tag)
+//    if (!tag_copy) goto error
+//
+//    if (!STACK_INIT(&context, pairs, INITIAL_STACK_SIZE)) goto error
+//
+//    MAPPING_NODE_INIT(node, tag_copy, pairs.start, pairs.end,
+//            style, mark, mark)
+//    if (!PUSH(&context, document.nodes, node)) goto error
+//
+//    return document.nodes.top - document.nodes.start
+//
+//error:
+//    STACK_DEL(&context, pairs)
+//    yaml_free(tag_copy)
+//
+//    return 0
+//}
+//
+///*
+// * Append an item to a sequence node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_sequence_item(document *yaml_document_t,
+//        sequence int, item int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(sequence > 0
+//            && document.nodes.start + sequence <= document.nodes.top)
+//                            // Valid sequence id is required.
+//    assert(document.nodes.start[sequence-1].type == YAML_SEQUENCE_NODE)
+//                            // A sequence node is required.
+//    assert(item > 0 && document.nodes.start + item <= document.nodes.top)
+//                            // Valid item id is required.
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[sequence-1].data.sequence.items, item))
+//        return 0
+//
+//    return 1
+//}
+//
+///*
+// * Append a pair of a key and a value to a mapping node.
+// */
+//
+//YAML_DECLARE(int)
+//yaml_document_append_mapping_pair(document *yaml_document_t,
+//        mapping int, key int, value int)
+//{
+//    struct {
+//        error yaml_error_type_t
+//    } context
+//
+//    pair yaml_node_pair_t
+//
+//    assert(document) // Non-NULL document is required.
+//    assert(mapping > 0
+//            && document.nodes.start + mapping <= document.nodes.top)
+//                            // Valid mapping id is required.
+//    assert(document.nodes.start[mapping-1].type == YAML_MAPPING_NODE)
+//                            // A mapping node is required.
+//    assert(key > 0 && document.nodes.start + key <= document.nodes.top)
+//                            // Valid key id is required.
+//    assert(value > 0 && document.nodes.start + value <= document.nodes.top)
+//                            // Valid value id is required.
+//
+//    pair.key = key
+//    pair.value = value
+//
+//    if (!PUSH(&context,
+//                document.nodes.start[mapping-1].data.mapping.pairs, pair))
+//        return 0
+//
+//    return 1
+//}
+//
+//

vendor/gopkg.in/yaml.v3/encode.go

@@ -0,0 +1,577 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+	"encoding"
+	"fmt"
+	"io"
+	"reflect"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+	"unicode/utf8"
+)
+
+type encoder struct {
+	emitter  yaml_emitter_t
+	event    yaml_event_t
+	out      []byte
+	flow     bool
+	indent   int
+	doneInit bool
+}
+
+func newEncoder() *encoder {
+	e := &encoder{}
+	yaml_emitter_initialize(&e.emitter)
+	yaml_emitter_set_output_string(&e.emitter, &e.out)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	return e
+}
+
+func newEncoderWithWriter(w io.Writer) *encoder {
+	e := &encoder{}
+	yaml_emitter_initialize(&e.emitter)
+	yaml_emitter_set_output_writer(&e.emitter, w)
+	yaml_emitter_set_unicode(&e.emitter, true)
+	return e
+}
+
+func (e *encoder) init() {
+	if e.doneInit {
+		return
+	}
+	if e.indent == 0 {
+		e.indent = 4
+	}
+	e.emitter.best_indent = e.indent
+	yaml_stream_start_event_initialize(&e.event, yaml_UTF8_ENCODING)
+	e.emit()
+	e.doneInit = true
+}
+
+func (e *encoder) finish() {
+	e.emitter.open_ended = false
+	yaml_stream_end_event_initialize(&e.event)
+	e.emit()
+}
+
+func (e *encoder) destroy() {
+	yaml_emitter_delete(&e.emitter)
+}
+
+func (e *encoder) emit() {
+	// This will internally delete the e.event value.
+	e.must(yaml_emitter_emit(&e.emitter, &e.event))
+}
+
+func (e *encoder) must(ok bool) {
+	if !ok {
+		msg := e.emitter.problem
+		if msg == "" {
+			msg = "unknown problem generating YAML content"
+		}
+		failf("%s", msg)
+	}
+}
+
+func (e *encoder) marshalDoc(tag string, in reflect.Value) {
+	e.init()
+	var node *Node
+	if in.IsValid() {
+		node, _ = in.Interface().(*Node)
+	}
+	if node != nil && node.Kind == DocumentNode {
+		e.nodev(in)
+	} else {
+		yaml_document_start_event_initialize(&e.event, nil, nil, true)
+		e.emit()
+		e.marshal(tag, in)
+		yaml_document_end_event_initialize(&e.event, true)
+		e.emit()
+	}
+}
+
+func (e *encoder) marshal(tag string, in reflect.Value) {
+	tag = shortTag(tag)
+	if !in.IsValid() || in.Kind() == reflect.Ptr && in.IsNil() {
+		e.nilv()
+		return
+	}
+	iface := in.Interface()
+	switch value := iface.(type) {
+	case *Node:
+		e.nodev(in)
+		return
+	case Node:
+		if !in.CanAddr() {
+			var n = reflect.New(in.Type()).Elem()
+			n.Set(in)
+			in = n
+		}
+		e.nodev(in.Addr())
+		return
+	case time.Time:
+		e.timev(tag, in)
+		return
+	case *time.Time:
+		e.timev(tag, in.Elem())
+		return
+	case time.Duration:
+		e.stringv(tag, reflect.ValueOf(value.String()))
+		return
+	case Marshaler:
+		v, err := value.MarshalYAML()
+		if err != nil {
+			fail(err)
+		}
+		if v == nil {
+			e.nilv()
+			return
+		}
+		e.marshal(tag, reflect.ValueOf(v))
+		return
+	case encoding.TextMarshaler:
+		text, err := value.MarshalText()
+		if err != nil {
+			fail(err)
+		}
+		in = reflect.ValueOf(string(text))
+	case nil:
+		e.nilv()
+		return
+	}
+	switch in.Kind() {
+	case reflect.Interface:
+		e.marshal(tag, in.Elem())
+	case reflect.Map:
+		e.mapv(tag, in)
+	case reflect.Ptr:
+		e.marshal(tag, in.Elem())
+	case reflect.Struct:
+		e.structv(tag, in)
+	case reflect.Slice, reflect.Array:
+		e.slicev(tag, in)
+	case reflect.String:
+		e.stringv(tag, in)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		e.intv(tag, in)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		e.uintv(tag, in)
+	case reflect.Float32, reflect.Float64:
+		e.floatv(tag, in)
+	case reflect.Bool:
+		e.boolv(tag, in)
+	default:
+		panic("cannot marshal type: " + in.Type().String())
+	}
+}
+
+func (e *encoder) mapv(tag string, in reflect.Value) {
+	e.mappingv(tag, func() {
+		keys := keyList(in.MapKeys())
+		sort.Sort(keys)
+		for _, k := range keys {
+			e.marshal("", k)
+			e.marshal("", in.MapIndex(k))
+		}
+	})
+}
+
+func (e *encoder) fieldByIndex(v reflect.Value, index []int) (field reflect.Value) {
+	for _, num := range index {
+		for {
+			if v.Kind() == reflect.Ptr {
+				if v.IsNil() {
+					return reflect.Value{}
+				}
+				v = v.Elem()
+				continue
+			}
+			break
+		}
+		v = v.Field(num)
+	}
+	return v
+}
+
+func (e *encoder) structv(tag string, in reflect.Value) {
+	sinfo, err := getStructInfo(in.Type())
+	if err != nil {
+		panic(err)
+	}
+	e.mappingv(tag, func() {
+		for _, info := range sinfo.FieldsList {
+			var value reflect.Value
+			if info.Inline == nil {
+				value = in.Field(info.Num)
+			} else {
+				value = e.fieldByIndex(in, info.Inline)
+				if !value.IsValid() {
+					continue
+				}
+			}
+			if info.OmitEmpty && isZero(value) {
+				continue
+			}
+			e.marshal("", reflect.ValueOf(info.Key))
+			e.flow = info.Flow
+			e.marshal("", value)
+		}
+		if sinfo.InlineMap >= 0 {
+			m := in.Field(sinfo.InlineMap)
+			if m.Len() > 0 {
+				e.flow = false
+				keys := keyList(m.MapKeys())
+				sort.Sort(keys)
+				for _, k := range keys {
+					if _, found := sinfo.FieldsMap[k.String()]; found {
+						panic(fmt.Sprintf("cannot have key %q in inlined map: conflicts with struct field", k.String()))
+					}
+					e.marshal("", k)
+					e.flow = false
+					e.marshal("", m.MapIndex(k))
+				}
+			}
+		}
+	})
+}
+
+func (e *encoder) mappingv(tag string, f func()) {
+	implicit := tag == ""
+	style := yaml_BLOCK_MAPPING_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_MAPPING_STYLE
+	}
+	yaml_mapping_start_event_initialize(&e.event, nil, []byte(tag), implicit, style)
+	e.emit()
+	f()
+	yaml_mapping_end_event_initialize(&e.event)
+	e.emit()
+}
+
+func (e *encoder) slicev(tag string, in reflect.Value) {
+	implicit := tag == ""
+	style := yaml_BLOCK_SEQUENCE_STYLE
+	if e.flow {
+		e.flow = false
+		style = yaml_FLOW_SEQUENCE_STYLE
+	}
+	e.must(yaml_sequence_start_event_initialize(&e.event, nil, []byte(tag), implicit, style))
+	e.emit()
+	n := in.Len()
+	for i := 0; i < n; i++ {
+		e.marshal("", in.Index(i))
+	}
+	e.must(yaml_sequence_end_event_initialize(&e.event))
+	e.emit()
+}
+
+// isBase60 returns whether s is in base 60 notation as defined in YAML 1.1.
+//
+// The base 60 float notation in YAML 1.1 is a terrible idea and is unsupported
+// in YAML 1.2 and by this package, but these should be marshalled quoted for
+// the time being for compatibility with other parsers.
+func isBase60Float(s string) (result bool) {
+	// Fast path.
+	if s == "" {
+		return false
+	}
+	c := s[0]
+	if !(c == '+' || c == '-' || c >= '0' && c <= '9') || strings.IndexByte(s, ':') < 0 {
+		return false
+	}
+	// Do the full match.
+	return base60float.MatchString(s)
+}
+
+// From http://yaml.org/type/float.html, except the regular expression there
+// is bogus. In practice parsers do not enforce the "\.[0-9_]*" suffix.
+var base60float = regexp.MustCompile(`^[-+]?[0-9][0-9_]*(?::[0-5]?[0-9])+(?:\.[0-9_]*)?$`)
+
+// isOldBool returns whether s is bool notation as defined in YAML 1.1.
+//
+// We continue to force strings that YAML 1.1 would interpret as booleans to be
+// rendered as quotes strings so that the marshalled output valid for YAML 1.1
+// parsing.
+func isOldBool(s string) (result bool) {
+	switch s {
+	case "y", "Y", "yes", "Yes", "YES", "on", "On", "ON",
+		"n", "N", "no", "No", "NO", "off", "Off", "OFF":
+		return true
+	default:
+		return false
+	}
+}
+
+func (e *encoder) stringv(tag string, in reflect.Value) {
+	var style yaml_scalar_style_t
+	s := in.String()
+	canUsePlain := true
+	switch {
+	case !utf8.ValidString(s):
+		if tag == binaryTag {
+			failf("explicitly tagged !!binary data must be base64-encoded")
+		}
+		if tag != "" {
+			failf("cannot marshal invalid UTF-8 data as %s", shortTag(tag))
+		}
+		// It can't be encoded directly as YAML so use a binary tag
+		// and encode it as base64.
+		tag = binaryTag
+		s = encodeBase64(s)
+	case tag == "":
+		// Check to see if it would resolve to a specific
+		// tag when encoded unquoted. If it doesn't,
+		// there's no need to quote it.
+		rtag, _ := resolve("", s)
+		canUsePlain = rtag == strTag && !(isBase60Float(s) || isOldBool(s))
+	}
+	// Note: it's possible for user code to emit invalid YAML
+	// if they explicitly specify a tag and a string containing
+	// text that's incompatible with that tag.
+	switch {
+	case strings.Contains(s, "\n"):
+		if e.flow {
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		} else {
+			style = yaml_LITERAL_SCALAR_STYLE
+		}
+	case canUsePlain:
+		style = yaml_PLAIN_SCALAR_STYLE
+	default:
+		style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+	}
+	e.emitScalar(s, "", tag, style, nil, nil, nil, nil)
+}
+
+func (e *encoder) boolv(tag string, in reflect.Value) {
+	var s string
+	if in.Bool() {
+		s = "true"
+	} else {
+		s = "false"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) intv(tag string, in reflect.Value) {
+	s := strconv.FormatInt(in.Int(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) uintv(tag string, in reflect.Value) {
+	s := strconv.FormatUint(in.Uint(), 10)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) timev(tag string, in reflect.Value) {
+	t := in.Interface().(time.Time)
+	s := t.Format(time.RFC3339Nano)
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) floatv(tag string, in reflect.Value) {
+	// Issue #352: When formatting, use the precision of the underlying value
+	precision := 64
+	if in.Kind() == reflect.Float32 {
+		precision = 32
+	}
+
+	s := strconv.FormatFloat(in.Float(), 'g', -1, precision)
+	switch s {
+	case "+Inf":
+		s = ".inf"
+	case "-Inf":
+		s = "-.inf"
+	case "NaN":
+		s = ".nan"
+	}
+	e.emitScalar(s, "", tag, yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) nilv() {
+	e.emitScalar("null", "", "", yaml_PLAIN_SCALAR_STYLE, nil, nil, nil, nil)
+}
+
+func (e *encoder) emitScalar(value, anchor, tag string, style yaml_scalar_style_t, head, line, foot, tail []byte) {
+	// TODO Kill this function. Replace all initialize calls by their underlining Go literals.
+	implicit := tag == ""
+	if !implicit {
+		tag = longTag(tag)
+	}
+	e.must(yaml_scalar_event_initialize(&e.event, []byte(anchor), []byte(tag), []byte(value), implicit, implicit, style))
+	e.event.head_comment = head
+	e.event.line_comment = line
+	e.event.foot_comment = foot
+	e.event.tail_comment = tail
+	e.emit()
+}
+
+func (e *encoder) nodev(in reflect.Value) {
+	e.node(in.Interface().(*Node), "")
+}
+
+func (e *encoder) node(node *Node, tail string) {
+	// Zero nodes behave as nil.
+	if node.Kind == 0 && node.IsZero() {
+		e.nilv()
+		return
+	}
+
+	// If the tag was not explicitly requested, and dropping it won't change the
+	// implicit tag of the value, don't include it in the presentation.
+	var tag = node.Tag
+	var stag = shortTag(tag)
+	var forceQuoting bool
+	if tag != "" && node.Style&TaggedStyle == 0 {
+		if node.Kind == ScalarNode {
+			if stag == strTag && node.Style&(SingleQuotedStyle|DoubleQuotedStyle|LiteralStyle|FoldedStyle) != 0 {
+				tag = ""
+			} else {
+				rtag, _ := resolve("", node.Value)
+				if rtag == stag {
+					tag = ""
+				} else if stag == strTag {
+					tag = ""
+					forceQuoting = true
+				}
+			}
+		} else {
+			var rtag string
+			switch node.Kind {
+			case MappingNode:
+				rtag = mapTag
+			case SequenceNode:
+				rtag = seqTag
+			}
+			if rtag == stag {
+				tag = ""
+			}
+		}
+	}
+
+	switch node.Kind {
+	case DocumentNode:
+		yaml_document_start_event_initialize(&e.event, nil, nil, true)
+		e.event.head_comment = []byte(node.HeadComment)
+		e.emit()
+		for _, node := range node.Content {
+			e.node(node, "")
+		}
+		yaml_document_end_event_initialize(&e.event, true)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case SequenceNode:
+		style := yaml_BLOCK_SEQUENCE_STYLE
+		if node.Style&FlowStyle != 0 {
+			style = yaml_FLOW_SEQUENCE_STYLE
+		}
+		e.must(yaml_sequence_start_event_initialize(&e.event, []byte(node.Anchor), []byte(longTag(tag)), tag == "", style))
+		e.event.head_comment = []byte(node.HeadComment)
+		e.emit()
+		for _, node := range node.Content {
+			e.node(node, "")
+		}
+		e.must(yaml_sequence_end_event_initialize(&e.event))
+		e.event.line_comment = []byte(node.LineComment)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case MappingNode:
+		style := yaml_BLOCK_MAPPING_STYLE
+		if node.Style&FlowStyle != 0 {
+			style = yaml_FLOW_MAPPING_STYLE
+		}
+		yaml_mapping_start_event_initialize(&e.event, []byte(node.Anchor), []byte(longTag(tag)), tag == "", style)
+		e.event.tail_comment = []byte(tail)
+		e.event.head_comment = []byte(node.HeadComment)
+		e.emit()
+
+		// The tail logic below moves the foot comment of prior keys to the following key,
+		// since the value for each key may be a nested structure and the foot needs to be
+		// processed only the entirety of the value is streamed. The last tail is processed
+		// with the mapping end event.
+		var tail string
+		for i := 0; i+1 < len(node.Content); i += 2 {
+			k := node.Content[i]
+			foot := k.FootComment
+			if foot != "" {
+				kopy := *k
+				kopy.FootComment = ""
+				k = &kopy
+			}
+			e.node(k, tail)
+			tail = foot
+
+			v := node.Content[i+1]
+			e.node(v, "")
+		}
+
+		yaml_mapping_end_event_initialize(&e.event)
+		e.event.tail_comment = []byte(tail)
+		e.event.line_comment = []byte(node.LineComment)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case AliasNode:
+		yaml_alias_event_initialize(&e.event, []byte(node.Value))
+		e.event.head_comment = []byte(node.HeadComment)
+		e.event.line_comment = []byte(node.LineComment)
+		e.event.foot_comment = []byte(node.FootComment)
+		e.emit()
+
+	case ScalarNode:
+		value := node.Value
+		if !utf8.ValidString(value) {
+			if stag == binaryTag {
+				failf("explicitly tagged !!binary data must be base64-encoded")
+			}
+			if stag != "" {
+				failf("cannot marshal invalid UTF-8 data as %s", stag)
+			}
+			// It can't be encoded directly as YAML so use a binary tag
+			// and encode it as base64.
+			tag = binaryTag
+			value = encodeBase64(value)
+		}
+
+		style := yaml_PLAIN_SCALAR_STYLE
+		switch {
+		case node.Style&DoubleQuotedStyle != 0:
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		case node.Style&SingleQuotedStyle != 0:
+			style = yaml_SINGLE_QUOTED_SCALAR_STYLE
+		case node.Style&LiteralStyle != 0:
+			style = yaml_LITERAL_SCALAR_STYLE
+		case node.Style&FoldedStyle != 0:
+			style = yaml_FOLDED_SCALAR_STYLE
+		case strings.Contains(value, "\n"):
+			style = yaml_LITERAL_SCALAR_STYLE
+		case forceQuoting:
+			style = yaml_DOUBLE_QUOTED_SCALAR_STYLE
+		}
+
+		e.emitScalar(value, node.Anchor, tag, style, []byte(node.HeadComment), []byte(node.LineComment), []byte(node.FootComment), []byte(tail))
+	default:
+		failf("cannot encode node with unknown kind %d", node.Kind)
+	}
+}

vendor/gopkg.in/yaml.v3/readerc.go

@@ -0,0 +1,434 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+import (
+	"io"
+)
+
+// Set the reader error and return 0.
+func yaml_parser_set_reader_error(parser *yaml_parser_t, problem string, offset int, value int) bool {
+	parser.error = yaml_READER_ERROR
+	parser.problem = problem
+	parser.problem_offset = offset
+	parser.problem_value = value
+	return false
+}
+
+// Byte order marks.
+const (
+	bom_UTF8    = "\xef\xbb\xbf"
+	bom_UTF16LE = "\xff\xfe"
+	bom_UTF16BE = "\xfe\xff"
+)
+
+// Determine the input stream encoding by checking the BOM symbol. If no BOM is
+// found, the UTF-8 encoding is assumed. Return 1 on success, 0 on failure.
+func yaml_parser_determine_encoding(parser *yaml_parser_t) bool {
+	// Ensure that we had enough bytes in the raw buffer.
+	for !parser.eof && len(parser.raw_buffer)-parser.raw_buffer_pos < 3 {
+		if !yaml_parser_update_raw_buffer(parser) {
+			return false
+		}
+	}
+
+	// Determine the encoding.
+	buf := parser.raw_buffer
+	pos := parser.raw_buffer_pos
+	avail := len(buf) - pos
+	if avail >= 2 && buf[pos] == bom_UTF16LE[0] && buf[pos+1] == bom_UTF16LE[1] {
+		parser.encoding = yaml_UTF16LE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 2 && buf[pos] == bom_UTF16BE[0] && buf[pos+1] == bom_UTF16BE[1] {
+		parser.encoding = yaml_UTF16BE_ENCODING
+		parser.raw_buffer_pos += 2
+		parser.offset += 2
+	} else if avail >= 3 && buf[pos] == bom_UTF8[0] && buf[pos+1] == bom_UTF8[1] && buf[pos+2] == bom_UTF8[2] {
+		parser.encoding = yaml_UTF8_ENCODING
+		parser.raw_buffer_pos += 3
+		parser.offset += 3
+	} else {
+		parser.encoding = yaml_UTF8_ENCODING
+	}
+	return true
+}
+
+// Update the raw buffer.
+func yaml_parser_update_raw_buffer(parser *yaml_parser_t) bool {
+	size_read := 0
+
+	// Return if the raw buffer is full.
+	if parser.raw_buffer_pos == 0 && len(parser.raw_buffer) == cap(parser.raw_buffer) {
+		return true
+	}
+
+	// Return on EOF.
+	if parser.eof {
+		return true
+	}
+
+	// Move the remaining bytes in the raw buffer to the beginning.
+	if parser.raw_buffer_pos > 0 && parser.raw_buffer_pos < len(parser.raw_buffer) {
+		copy(parser.raw_buffer, parser.raw_buffer[parser.raw_buffer_pos:])
+	}
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)-parser.raw_buffer_pos]
+	parser.raw_buffer_pos = 0
+
+	// Call the read handler to fill the buffer.
+	size_read, err := parser.read_handler(parser, parser.raw_buffer[len(parser.raw_buffer):cap(parser.raw_buffer)])
+	parser.raw_buffer = parser.raw_buffer[:len(parser.raw_buffer)+size_read]
+	if err == io.EOF {
+		parser.eof = true
+	} else if err != nil {
+		return yaml_parser_set_reader_error(parser, "input error: "+err.Error(), parser.offset, -1)
+	}
+	return true
+}
+
+// Ensure that the buffer contains at least `length` characters.
+// Return true on success, false on failure.
+//
+// The length is supposed to be significantly less that the buffer size.
+func yaml_parser_update_buffer(parser *yaml_parser_t, length int) bool {
+	if parser.read_handler == nil {
+		panic("read handler must be set")
+	}
+
+	// [Go] This function was changed to guarantee the requested length size at EOF.
+	// The fact we need to do this is pretty awful, but the description above implies
+	// for that to be the case, and there are tests
+
+	// If the EOF flag is set and the raw buffer is empty, do nothing.
+	if parser.eof && parser.raw_buffer_pos == len(parser.raw_buffer) {
+		// [Go] ACTUALLY! Read the documentation of this function above.
+		// This is just broken. To return true, we need to have the
+		// given length in the buffer. Not doing that means every single
+		// check that calls this function to make sure the buffer has a
+		// given length is Go) panicking; or C) accessing invalid memory.
+		//return true
+	}
+
+	// Return if the buffer contains enough characters.
+	if parser.unread >= length {
+		return true
+	}
+
+	// Determine the input encoding if it is not known yet.
+	if parser.encoding == yaml_ANY_ENCODING {
+		if !yaml_parser_determine_encoding(parser) {
+			return false
+		}
+	}
+
+	// Move the unread characters to the beginning of the buffer.
+	buffer_len := len(parser.buffer)
+	if parser.buffer_pos > 0 && parser.buffer_pos < buffer_len {
+		copy(parser.buffer, parser.buffer[parser.buffer_pos:])
+		buffer_len -= parser.buffer_pos
+		parser.buffer_pos = 0
+	} else if parser.buffer_pos == buffer_len {
+		buffer_len = 0
+		parser.buffer_pos = 0
+	}
+
+	// Open the whole buffer for writing, and cut it before returning.
+	parser.buffer = parser.buffer[:cap(parser.buffer)]
+
+	// Fill the buffer until it has enough characters.
+	first := true
+	for parser.unread < length {
+
+		// Fill the raw buffer if necessary.
+		if !first || parser.raw_buffer_pos == len(parser.raw_buffer) {
+			if !yaml_parser_update_raw_buffer(parser) {
+				parser.buffer = parser.buffer[:buffer_len]
+				return false
+			}
+		}
+		first = false
+
+		// Decode the raw buffer.
+	inner:
+		for parser.raw_buffer_pos != len(parser.raw_buffer) {
+			var value rune
+			var width int
+
+			raw_unread := len(parser.raw_buffer) - parser.raw_buffer_pos
+
+			// Decode the next character.
+			switch parser.encoding {
+			case yaml_UTF8_ENCODING:
+				// Decode a UTF-8 character.  Check RFC 3629
+				// (http://www.ietf.org/rfc/rfc3629.txt) for more details.
+				//
+				// The following table (taken from the RFC) is used for
+				// decoding.
+				//
+				//    Char. number range |        UTF-8 octet sequence
+				//      (hexadecimal)    |              (binary)
+				//   --------------------+------------------------------------
+				//   0000 0000-0000 007F | 0xxxxxxx
+				//   0000 0080-0000 07FF | 110xxxxx 10xxxxxx
+				//   0000 0800-0000 FFFF | 1110xxxx 10xxxxxx 10xxxxxx
+				//   0001 0000-0010 FFFF | 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				//
+				// Additionally, the characters in the range 0xD800-0xDFFF
+				// are prohibited as they are reserved for use with UTF-16
+				// surrogate pairs.
+
+				// Determine the length of the UTF-8 sequence.
+				octet := parser.raw_buffer[parser.raw_buffer_pos]
+				switch {
+				case octet&0x80 == 0x00:
+					width = 1
+				case octet&0xE0 == 0xC0:
+					width = 2
+				case octet&0xF0 == 0xE0:
+					width = 3
+				case octet&0xF8 == 0xF0:
+					width = 4
+				default:
+					// The leading octet is invalid.
+					return yaml_parser_set_reader_error(parser,
+						"invalid leading UTF-8 octet",
+						parser.offset, int(octet))
+				}
+
+				// Check if the raw buffer contains an incomplete character.
+				if width > raw_unread {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-8 octet sequence",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Decode the leading octet.
+				switch {
+				case octet&0x80 == 0x00:
+					value = rune(octet & 0x7F)
+				case octet&0xE0 == 0xC0:
+					value = rune(octet & 0x1F)
+				case octet&0xF0 == 0xE0:
+					value = rune(octet & 0x0F)
+				case octet&0xF8 == 0xF0:
+					value = rune(octet & 0x07)
+				default:
+					value = 0
+				}
+
+				// Check and decode the trailing octets.
+				for k := 1; k < width; k++ {
+					octet = parser.raw_buffer[parser.raw_buffer_pos+k]
+
+					// Check if the octet is valid.
+					if (octet & 0xC0) != 0x80 {
+						return yaml_parser_set_reader_error(parser,
+							"invalid trailing UTF-8 octet",
+							parser.offset+k, int(octet))
+					}
+
+					// Decode the octet.
+					value = (value << 6) + rune(octet&0x3F)
+				}
+
+				// Check the length of the sequence against the value.
+				switch {
+				case width == 1:
+				case width == 2 && value >= 0x80:
+				case width == 3 && value >= 0x800:
+				case width == 4 && value >= 0x10000:
+				default:
+					return yaml_parser_set_reader_error(parser,
+						"invalid length of a UTF-8 sequence",
+						parser.offset, -1)
+				}
+
+				// Check the range of the value.
+				if value >= 0xD800 && value <= 0xDFFF || value > 0x10FFFF {
+					return yaml_parser_set_reader_error(parser,
+						"invalid Unicode character",
+						parser.offset, int(value))
+				}
+
+			case yaml_UTF16LE_ENCODING, yaml_UTF16BE_ENCODING:
+				var low, high int
+				if parser.encoding == yaml_UTF16LE_ENCODING {
+					low, high = 0, 1
+				} else {
+					low, high = 1, 0
+				}
+
+				// The UTF-16 encoding is not as simple as one might
+				// naively think.  Check RFC 2781
+				// (http://www.ietf.org/rfc/rfc2781.txt).
+				//
+				// Normally, two subsequent bytes describe a Unicode
+				// character.  However a special technique (called a
+				// surrogate pair) is used for specifying character
+				// values larger than 0xFFFF.
+				//
+				// A surrogate pair consists of two pseudo-characters:
+				//      high surrogate area (0xD800-0xDBFF)
+				//      low surrogate area (0xDC00-0xDFFF)
+				//
+				// The following formulas are used for decoding
+				// and encoding characters using surrogate pairs:
+				//
+				//  U  = U' + 0x10000   (0x01 00 00 <= U <= 0x10 FF FF)
+				//  U' = yyyyyyyyyyxxxxxxxxxx   (0 <= U' <= 0x0F FF FF)
+				//  W1 = 110110yyyyyyyyyy
+				//  W2 = 110111xxxxxxxxxx
+				//
+				// where U is the character value, W1 is the high surrogate
+				// area, W2 is the low surrogate area.
+
+				// Check for incomplete UTF-16 character.
+				if raw_unread < 2 {
+					if parser.eof {
+						return yaml_parser_set_reader_error(parser,
+							"incomplete UTF-16 character",
+							parser.offset, -1)
+					}
+					break inner
+				}
+
+				// Get the character.
+				value = rune(parser.raw_buffer[parser.raw_buffer_pos+low]) +
+					(rune(parser.raw_buffer[parser.raw_buffer_pos+high]) << 8)
+
+				// Check for unexpected low surrogate area.
+				if value&0xFC00 == 0xDC00 {
+					return yaml_parser_set_reader_error(parser,
+						"unexpected low surrogate area",
+						parser.offset, int(value))
+				}
+
+				// Check for a high surrogate area.
+				if value&0xFC00 == 0xD800 {
+					width = 4
+
+					// Check for incomplete surrogate pair.
+					if raw_unread < 4 {
+						if parser.eof {
+							return yaml_parser_set_reader_error(parser,
+								"incomplete UTF-16 surrogate pair",
+								parser.offset, -1)
+						}
+						break inner
+					}
+
+					// Get the next character.
+					value2 := rune(parser.raw_buffer[parser.raw_buffer_pos+low+2]) +
+						(rune(parser.raw_buffer[parser.raw_buffer_pos+high+2]) << 8)
+
+					// Check for a low surrogate area.
+					if value2&0xFC00 != 0xDC00 {
+						return yaml_parser_set_reader_error(parser,
+							"expected low surrogate area",
+							parser.offset+2, int(value2))
+					}
+
+					// Generate the value of the surrogate pair.
+					value = 0x10000 + ((value & 0x3FF) << 10) + (value2 & 0x3FF)
+				} else {
+					width = 2
+				}
+
+			default:
+				panic("impossible")
+			}
+
+			// Check if the character is in the allowed range:
+			//      #x9 | #xA | #xD | [#x20-#x7E]               (8 bit)
+			//      | #x85 | [#xA0-#xD7FF] | [#xE000-#xFFFD]    (16 bit)
+			//      | [#x10000-#x10FFFF]                        (32 bit)
+			switch {
+			case value == 0x09:
+			case value == 0x0A:
+			case value == 0x0D:
+			case value >= 0x20 && value <= 0x7E:
+			case value == 0x85:
+			case value >= 0xA0 && value <= 0xD7FF:
+			case value >= 0xE000 && value <= 0xFFFD:
+			case value >= 0x10000 && value <= 0x10FFFF:
+			default:
+				return yaml_parser_set_reader_error(parser,
+					"control characters are not allowed",
+					parser.offset, int(value))
+			}
+
+			// Move the raw pointers.
+			parser.raw_buffer_pos += width
+			parser.offset += width
+
+			// Finally put the character into the buffer.
+			if value <= 0x7F {
+				// 0000 0000-0000 007F . 0xxxxxxx
+				parser.buffer[buffer_len+0] = byte(value)
+				buffer_len += 1
+			} else if value <= 0x7FF {
+				// 0000 0080-0000 07FF . 110xxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xC0 + (value >> 6))
+				parser.buffer[buffer_len+1] = byte(0x80 + (value & 0x3F))
+				buffer_len += 2
+			} else if value <= 0xFFFF {
+				// 0000 0800-0000 FFFF . 1110xxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xE0 + (value >> 12))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + (value & 0x3F))
+				buffer_len += 3
+			} else {
+				// 0001 0000-0010 FFFF . 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
+				parser.buffer[buffer_len+0] = byte(0xF0 + (value >> 18))
+				parser.buffer[buffer_len+1] = byte(0x80 + ((value >> 12) & 0x3F))
+				parser.buffer[buffer_len+2] = byte(0x80 + ((value >> 6) & 0x3F))
+				parser.buffer[buffer_len+3] = byte(0x80 + (value & 0x3F))
+				buffer_len += 4
+			}
+
+			parser.unread++
+		}
+
+		// On EOF, put NUL into the buffer and return.
+		if parser.eof {
+			parser.buffer[buffer_len] = 0
+			buffer_len++
+			parser.unread++
+			break
+		}
+	}
+	// [Go] Read the documentation of this function above. To return true,
+	// we need to have the given length in the buffer. Not doing that means
+	// every single check that calls this function to make sure the buffer
+	// has a given length is Go) panicking; or C) accessing invalid memory.
+	// This happens here due to the EOF above breaking early.
+	for buffer_len < length {
+		parser.buffer[buffer_len] = 0
+		buffer_len++
+	}
+	parser.buffer = parser.buffer[:buffer_len]
+	return true
+}

vendor/gopkg.in/yaml.v3/resolve.go

@@ -0,0 +1,326 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+	"encoding/base64"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type resolveMapItem struct {
+	value interface{}
+	tag   string
+}
+
+var resolveTable = make([]byte, 256)
+var resolveMap = make(map[string]resolveMapItem)
+
+func init() {
+	t := resolveTable
+	t[int('+')] = 'S' // Sign
+	t[int('-')] = 'S'
+	for _, c := range "0123456789" {
+		t[int(c)] = 'D' // Digit
+	}
+	for _, c := range "yYnNtTfFoO~" {
+		t[int(c)] = 'M' // In map
+	}
+	t[int('.')] = '.' // Float (potentially in map)
+
+	var resolveMapList = []struct {
+		v   interface{}
+		tag string
+		l   []string
+	}{
+		{true, boolTag, []string{"true", "True", "TRUE"}},
+		{false, boolTag, []string{"false", "False", "FALSE"}},
+		{nil, nullTag, []string{"", "~", "null", "Null", "NULL"}},
+		{math.NaN(), floatTag, []string{".nan", ".NaN", ".NAN"}},
+		{math.Inf(+1), floatTag, []string{".inf", ".Inf", ".INF"}},
+		{math.Inf(+1), floatTag, []string{"+.inf", "+.Inf", "+.INF"}},
+		{math.Inf(-1), floatTag, []string{"-.inf", "-.Inf", "-.INF"}},
+		{"<<", mergeTag, []string{"<<"}},
+	}
+
+	m := resolveMap
+	for _, item := range resolveMapList {
+		for _, s := range item.l {
+			m[s] = resolveMapItem{item.v, item.tag}
+		}
+	}
+}
+
+const (
+	nullTag      = "!!null"
+	boolTag      = "!!bool"
+	strTag       = "!!str"
+	intTag       = "!!int"
+	floatTag     = "!!float"
+	timestampTag = "!!timestamp"
+	seqTag       = "!!seq"
+	mapTag       = "!!map"
+	binaryTag    = "!!binary"
+	mergeTag     = "!!merge"
+)
+
+var longTags = make(map[string]string)
+var shortTags = make(map[string]string)
+
+func init() {
+	for _, stag := range []string{nullTag, boolTag, strTag, intTag, floatTag, timestampTag, seqTag, mapTag, binaryTag, mergeTag} {
+		ltag := longTag(stag)
+		longTags[stag] = ltag
+		shortTags[ltag] = stag
+	}
+}
+
+const longTagPrefix = "tag:yaml.org,2002:"
+
+func shortTag(tag string) string {
+	if strings.HasPrefix(tag, longTagPrefix) {
+		if stag, ok := shortTags[tag]; ok {
+			return stag
+		}
+		return "!!" + tag[len(longTagPrefix):]
+	}
+	return tag
+}
+
+func longTag(tag string) string {
+	if strings.HasPrefix(tag, "!!") {
+		if ltag, ok := longTags[tag]; ok {
+			return ltag
+		}
+		return longTagPrefix + tag[2:]
+	}
+	return tag
+}
+
+func resolvableTag(tag string) bool {
+	switch tag {
+	case "", strTag, boolTag, intTag, floatTag, nullTag, timestampTag:
+		return true
+	}
+	return false
+}
+
+var yamlStyleFloat = regexp.MustCompile(`^[-+]?(\.[0-9]+|[0-9]+(\.[0-9]*)?)([eE][-+]?[0-9]+)?$`)
+
+func resolve(tag string, in string) (rtag string, out interface{}) {
+	tag = shortTag(tag)
+	if !resolvableTag(tag) {
+		return tag, in
+	}
+
+	defer func() {
+		switch tag {
+		case "", rtag, strTag, binaryTag:
+			return
+		case floatTag:
+			if rtag == intTag {
+				switch v := out.(type) {
+				case int64:
+					rtag = floatTag
+					out = float64(v)
+					return
+				case int:
+					rtag = floatTag
+					out = float64(v)
+					return
+				}
+			}
+		}
+		failf("cannot decode %s `%s` as a %s", shortTag(rtag), in, shortTag(tag))
+	}()
+
+	// Any data is accepted as a !!str or !!binary.
+	// Otherwise, the prefix is enough of a hint about what it might be.
+	hint := byte('N')
+	if in != "" {
+		hint = resolveTable[in[0]]
+	}
+	if hint != 0 && tag != strTag && tag != binaryTag {
+		// Handle things we can lookup in a map.
+		if item, ok := resolveMap[in]; ok {
+			return item.tag, item.value
+		}
+
+		// Base 60 floats are a bad idea, were dropped in YAML 1.2, and
+		// are purposefully unsupported here. They're still quoted on
+		// the way out for compatibility with other parser, though.
+
+		switch hint {
+		case 'M':
+			// We've already checked the map above.
+
+		case '.':
+			// Not in the map, so maybe a normal float.
+			floatv, err := strconv.ParseFloat(in, 64)
+			if err == nil {
+				return floatTag, floatv
+			}
+
+		case 'D', 'S':
+			// Int, float, or timestamp.
+			// Only try values as a timestamp if the value is unquoted or there's an explicit
+			// !!timestamp tag.
+			if tag == "" || tag == timestampTag {
+				t, ok := parseTimestamp(in)
+				if ok {
+					return timestampTag, t
+				}
+			}
+
+			plain := strings.Replace(in, "_", "", -1)
+			intv, err := strconv.ParseInt(plain, 0, 64)
+			if err == nil {
+				if intv == int64(int(intv)) {
+					return intTag, int(intv)
+				} else {
+					return intTag, intv
+				}
+			}
+			uintv, err := strconv.ParseUint(plain, 0, 64)
+			if err == nil {
+				return intTag, uintv
+			}
+			if yamlStyleFloat.MatchString(plain) {
+				floatv, err := strconv.ParseFloat(plain, 64)
+				if err == nil {
+					return floatTag, floatv
+				}
+			}
+			if strings.HasPrefix(plain, "0b") {
+				intv, err := strconv.ParseInt(plain[2:], 2, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+				uintv, err := strconv.ParseUint(plain[2:], 2, 64)
+				if err == nil {
+					return intTag, uintv
+				}
+			} else if strings.HasPrefix(plain, "-0b") {
+				intv, err := strconv.ParseInt("-"+plain[3:], 2, 64)
+				if err == nil {
+					if true || intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+			}
+			// Octals as introduced in version 1.2 of the spec.
+			// Octals from the 1.1 spec, spelled as 0777, are still
+			// decoded by default in v3 as well for compatibility.
+			// May be dropped in v4 depending on how usage evolves.
+			if strings.HasPrefix(plain, "0o") {
+				intv, err := strconv.ParseInt(plain[2:], 8, 64)
+				if err == nil {
+					if intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+				uintv, err := strconv.ParseUint(plain[2:], 8, 64)
+				if err == nil {
+					return intTag, uintv
+				}
+			} else if strings.HasPrefix(plain, "-0o") {
+				intv, err := strconv.ParseInt("-"+plain[3:], 8, 64)
+				if err == nil {
+					if true || intv == int64(int(intv)) {
+						return intTag, int(intv)
+					} else {
+						return intTag, intv
+					}
+				}
+			}
+		default:
+			panic("internal error: missing handler for resolver table: " + string(rune(hint)) + " (with " + in + ")")
+		}
+	}
+	return strTag, in
+}
+
+// encodeBase64 encodes s as base64 that is broken up into multiple lines
+// as appropriate for the resulting length.
+func encodeBase64(s string) string {
+	const lineLen = 70
+	encLen := base64.StdEncoding.EncodedLen(len(s))
+	lines := encLen/lineLen + 1
+	buf := make([]byte, encLen*2+lines)
+	in := buf[0:encLen]
+	out := buf[encLen:]
+	base64.StdEncoding.Encode(in, []byte(s))
+	k := 0
+	for i := 0; i < len(in); i += lineLen {
+		j := i + lineLen
+		if j > len(in) {
+			j = len(in)
+		}
+		k += copy(out[k:], in[i:j])
+		if lines > 1 {
+			out[k] = '\n'
+			k++
+		}
+	}
+	return string(out[:k])
+}
+
+// This is a subset of the formats allowed by the regular expression
+// defined at http://yaml.org/type/timestamp.html.
+var allowedTimestampFormats = []string{
+	"2006-1-2T15:4:5.999999999Z07:00", // RCF3339Nano with short date fields.
+	"2006-1-2t15:4:5.999999999Z07:00", // RFC3339Nano with short date fields and lower-case "t".
+	"2006-1-2 15:4:5.999999999",       // space separated with no time zone
+	"2006-1-2",                        // date only
+	// Notable exception: time.Parse cannot handle: "2001-12-14 21:59:43.10 -5"
+	// from the set of examples.
+}
+
+// parseTimestamp parses s as a timestamp string and
+// returns the timestamp and reports whether it succeeded.
+// Timestamp formats are defined at http://yaml.org/type/timestamp.html
+func parseTimestamp(s string) (time.Time, bool) {
+	// TODO write code to check all the formats supported by
+	// http://yaml.org/type/timestamp.html instead of using time.Parse.
+
+	// Quick check: all date formats start with YYYY-.
+	i := 0
+	for ; i < len(s); i++ {
+		if c := s[i]; c < '0' || c > '9' {
+			break
+		}
+	}
+	if i != 4 || i == len(s) || s[i] != '-' {
+		return time.Time{}, false
+	}
+	for _, format := range allowedTimestampFormats {
+		if t, err := time.Parse(format, s); err == nil {
+			return t, true
+		}
+	}
+	return time.Time{}, false
+}

vendor/gopkg.in/yaml.v3/sorter.go

@@ -0,0 +1,134 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package yaml
+
+import (
+	"reflect"
+	"unicode"
+)
+
+type keyList []reflect.Value
+
+func (l keyList) Len() int      { return len(l) }
+func (l keyList) Swap(i, j int) { l[i], l[j] = l[j], l[i] }
+func (l keyList) Less(i, j int) bool {
+	a := l[i]
+	b := l[j]
+	ak := a.Kind()
+	bk := b.Kind()
+	for (ak == reflect.Interface || ak == reflect.Ptr) && !a.IsNil() {
+		a = a.Elem()
+		ak = a.Kind()
+	}
+	for (bk == reflect.Interface || bk == reflect.Ptr) && !b.IsNil() {
+		b = b.Elem()
+		bk = b.Kind()
+	}
+	af, aok := keyFloat(a)
+	bf, bok := keyFloat(b)
+	if aok && bok {
+		if af != bf {
+			return af < bf
+		}
+		if ak != bk {
+			return ak < bk
+		}
+		return numLess(a, b)
+	}
+	if ak != reflect.String || bk != reflect.String {
+		return ak < bk
+	}
+	ar, br := []rune(a.String()), []rune(b.String())
+	digits := false
+	for i := 0; i < len(ar) && i < len(br); i++ {
+		if ar[i] == br[i] {
+			digits = unicode.IsDigit(ar[i])
+			continue
+		}
+		al := unicode.IsLetter(ar[i])
+		bl := unicode.IsLetter(br[i])
+		if al && bl {
+			return ar[i] < br[i]
+		}
+		if al || bl {
+			if digits {
+				return al
+			} else {
+				return bl
+			}
+		}
+		var ai, bi int
+		var an, bn int64
+		if ar[i] == '0' || br[i] == '0' {
+			for j := i - 1; j >= 0 && unicode.IsDigit(ar[j]); j-- {
+				if ar[j] != '0' {
+					an = 1
+					bn = 1
+					break
+				}
+			}
+		}
+		for ai = i; ai < len(ar) && unicode.IsDigit(ar[ai]); ai++ {
+			an = an*10 + int64(ar[ai]-'0')
+		}
+		for bi = i; bi < len(br) && unicode.IsDigit(br[bi]); bi++ {
+			bn = bn*10 + int64(br[bi]-'0')
+		}
+		if an != bn {
+			return an < bn
+		}
+		if ai != bi {
+			return ai < bi
+		}
+		return ar[i] < br[i]
+	}
+	return len(ar) < len(br)
+}
+
+// keyFloat returns a float value for v if it is a number/bool
+// and whether it is a number/bool or not.
+func keyFloat(v reflect.Value) (f float64, ok bool) {
+	switch v.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return float64(v.Int()), true
+	case reflect.Float32, reflect.Float64:
+		return v.Float(), true
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return float64(v.Uint()), true
+	case reflect.Bool:
+		if v.Bool() {
+			return 1, true
+		}
+		return 0, true
+	}
+	return 0, false
+}
+
+// numLess returns whether a < b.
+// a and b must necessarily have the same kind.
+func numLess(a, b reflect.Value) bool {
+	switch a.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return a.Int() < b.Int()
+	case reflect.Float32, reflect.Float64:
+		return a.Float() < b.Float()
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return a.Uint() < b.Uint()
+	case reflect.Bool:
+		return !a.Bool() && b.Bool()
+	}
+	panic("not a number")
+}

vendor/gopkg.in/yaml.v3/writerc.go

@@ -0,0 +1,48 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+// Set the writer error and return false.
+func yaml_emitter_set_writer_error(emitter *yaml_emitter_t, problem string) bool {
+	emitter.error = yaml_WRITER_ERROR
+	emitter.problem = problem
+	return false
+}
+
+// Flush the output buffer.
+func yaml_emitter_flush(emitter *yaml_emitter_t) bool {
+	if emitter.write_handler == nil {
+		panic("write handler not set")
+	}
+
+	// Check if the buffer is empty.
+	if emitter.buffer_pos == 0 {
+		return true
+	}
+
+	if err := emitter.write_handler(emitter, emitter.buffer[:emitter.buffer_pos]); err != nil {
+		return yaml_emitter_set_writer_error(emitter, "write error: "+err.Error())
+	}
+	emitter.buffer_pos = 0
+	return true
+}

vendor/gopkg.in/yaml.v3/yaml.go

@@ -0,0 +1,698 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package yaml implements YAML support for the Go language.
+//
+// Source code and other details for the project are available at GitHub:
+//
+//   https://github.com/go-yaml/yaml
+//
+package yaml
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+	"sync"
+	"unicode/utf8"
+)
+
+// The Unmarshaler interface may be implemented by types to customize their
+// behavior when being unmarshaled from a YAML document.
+type Unmarshaler interface {
+	UnmarshalYAML(value *Node) error
+}
+
+type obsoleteUnmarshaler interface {
+	UnmarshalYAML(unmarshal func(interface{}) error) error
+}
+
+// The Marshaler interface may be implemented by types to customize their
+// behavior when being marshaled into a YAML document. The returned value
+// is marshaled in place of the original value implementing Marshaler.
+//
+// If an error is returned by MarshalYAML, the marshaling procedure stops
+// and returns with the provided error.
+type Marshaler interface {
+	MarshalYAML() (interface{}, error)
+}
+
+// Unmarshal decodes the first document found within the in byte slice
+// and assigns decoded values into the out value.
+//
+// Maps and pointers (to a struct, string, int, etc) are accepted as out
+// values. If an internal pointer within a struct is not initialized,
+// the yaml package will initialize it if necessary for unmarshalling
+// the provided data. The out parameter must not be nil.
+//
+// The type of the decoded values should be compatible with the respective
+// values in out. If one or more values cannot be decoded due to a type
+// mismatches, decoding continues partially until the end of the YAML
+// content, and a *yaml.TypeError is returned with details for all
+// missed values.
+//
+// Struct fields are only unmarshalled if they are exported (have an
+// upper case first letter), and are unmarshalled using the field name
+// lowercased as the default key. Custom keys may be defined via the
+// "yaml" name in the field tag: the content preceding the first comma
+// is used as the key, and the following comma-separated options are
+// used to tweak the marshalling process (see Marshal).
+// Conflicting names result in a runtime error.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     var t T
+//     yaml.Unmarshal([]byte("a: 1\nb: 2"), &t)
+//
+// See the documentation of Marshal for the format of tags and a list of
+// supported tag options.
+//
+func Unmarshal(in []byte, out interface{}) (err error) {
+	return unmarshal(in, out, false)
+}
+
+// A Decoder reads and decodes YAML values from an input stream.
+type Decoder struct {
+	parser      *parser
+	knownFields bool
+}
+
+// NewDecoder returns a new decoder that reads from r.
+//
+// The decoder introduces its own buffering and may read
+// data from r beyond the YAML values requested.
+func NewDecoder(r io.Reader) *Decoder {
+	return &Decoder{
+		parser: newParserFromReader(r),
+	}
+}
+
+// KnownFields ensures that the keys in decoded mappings to
+// exist as fields in the struct being decoded into.
+func (dec *Decoder) KnownFields(enable bool) {
+	dec.knownFields = enable
+}
+
+// Decode reads the next YAML-encoded value from its input
+// and stores it in the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about the
+// conversion of YAML into a Go value.
+func (dec *Decoder) Decode(v interface{}) (err error) {
+	d := newDecoder()
+	d.knownFields = dec.knownFields
+	defer handleErr(&err)
+	node := dec.parser.parse()
+	if node == nil {
+		return io.EOF
+	}
+	out := reflect.ValueOf(v)
+	if out.Kind() == reflect.Ptr && !out.IsNil() {
+		out = out.Elem()
+	}
+	d.unmarshal(node, out)
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+// Decode decodes the node and stores its data into the value pointed to by v.
+//
+// See the documentation for Unmarshal for details about the
+// conversion of YAML into a Go value.
+func (n *Node) Decode(v interface{}) (err error) {
+	d := newDecoder()
+	defer handleErr(&err)
+	out := reflect.ValueOf(v)
+	if out.Kind() == reflect.Ptr && !out.IsNil() {
+		out = out.Elem()
+	}
+	d.unmarshal(n, out)
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+func unmarshal(in []byte, out interface{}, strict bool) (err error) {
+	defer handleErr(&err)
+	d := newDecoder()
+	p := newParser(in)
+	defer p.destroy()
+	node := p.parse()
+	if node != nil {
+		v := reflect.ValueOf(out)
+		if v.Kind() == reflect.Ptr && !v.IsNil() {
+			v = v.Elem()
+		}
+		d.unmarshal(node, v)
+	}
+	if len(d.terrors) > 0 {
+		return &TypeError{d.terrors}
+	}
+	return nil
+}
+
+// Marshal serializes the value provided into a YAML document. The structure
+// of the generated document will reflect the structure of the value itself.
+// Maps and pointers (to struct, string, int, etc) are accepted as the in value.
+//
+// Struct fields are only marshalled if they are exported (have an upper case
+// first letter), and are marshalled using the field name lowercased as the
+// default key. Custom keys may be defined via the "yaml" name in the field
+// tag: the content preceding the first comma is used as the key, and the
+// following comma-separated options are used to tweak the marshalling process.
+// Conflicting names result in a runtime error.
+//
+// The field tag format accepted is:
+//
+//     `(...) yaml:"[<key>][,<flag1>[,<flag2>]]" (...)`
+//
+// The following flags are currently supported:
+//
+//     omitempty    Only include the field if it's not set to the zero
+//                  value for the type or to empty slices or maps.
+//                  Zero valued structs will be omitted if all their public
+//                  fields are zero, unless they implement an IsZero
+//                  method (see the IsZeroer interface type), in which
+//                  case the field will be excluded if IsZero returns true.
+//
+//     flow         Marshal using a flow style (useful for structs,
+//                  sequences and maps).
+//
+//     inline       Inline the field, which must be a struct or a map,
+//                  causing all of its fields or keys to be processed as if
+//                  they were part of the outer struct. For maps, keys must
+//                  not conflict with the yaml keys of other struct fields.
+//
+// In addition, if the key is "-", the field is ignored.
+//
+// For example:
+//
+//     type T struct {
+//         F int `yaml:"a,omitempty"`
+//         B int
+//     }
+//     yaml.Marshal(&T{B: 2}) // Returns "b: 2\n"
+//     yaml.Marshal(&T{F: 1}} // Returns "a: 1\nb: 0\n"
+//
+func Marshal(in interface{}) (out []byte, err error) {
+	defer handleErr(&err)
+	e := newEncoder()
+	defer e.destroy()
+	e.marshalDoc("", reflect.ValueOf(in))
+	e.finish()
+	out = e.out
+	return
+}
+
+// An Encoder writes YAML values to an output stream.
+type Encoder struct {
+	encoder *encoder
+}
+
+// NewEncoder returns a new encoder that writes to w.
+// The Encoder should be closed after use to flush all data
+// to w.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{
+		encoder: newEncoderWithWriter(w),
+	}
+}
+
+// Encode writes the YAML encoding of v to the stream.
+// If multiple items are encoded to the stream, the
+// second and subsequent document will be preceded
+// with a "---" document separator, but the first will not.
+//
+// See the documentation for Marshal for details about the conversion of Go
+// values to YAML.
+func (e *Encoder) Encode(v interface{}) (err error) {
+	defer handleErr(&err)
+	e.encoder.marshalDoc("", reflect.ValueOf(v))
+	return nil
+}
+
+// Encode encodes value v and stores its representation in n.
+//
+// See the documentation for Marshal for details about the
+// conversion of Go values into YAML.
+func (n *Node) Encode(v interface{}) (err error) {
+	defer handleErr(&err)
+	e := newEncoder()
+	defer e.destroy()
+	e.marshalDoc("", reflect.ValueOf(v))
+	e.finish()
+	p := newParser(e.out)
+	p.textless = true
+	defer p.destroy()
+	doc := p.parse()
+	*n = *doc.Content[0]
+	return nil
+}
+
+// SetIndent changes the used indentation used when encoding.
+func (e *Encoder) SetIndent(spaces int) {
+	if spaces < 0 {
+		panic("yaml: cannot indent to a negative number of spaces")
+	}
+	e.encoder.indent = spaces
+}
+
+// Close closes the encoder by writing any remaining data.
+// It does not write a stream terminating string "...".
+func (e *Encoder) Close() (err error) {
+	defer handleErr(&err)
+	e.encoder.finish()
+	return nil
+}
+
+func handleErr(err *error) {
+	if v := recover(); v != nil {
+		if e, ok := v.(yamlError); ok {
+			*err = e.err
+		} else {
+			panic(v)
+		}
+	}
+}
+
+type yamlError struct {
+	err error
+}
+
+func fail(err error) {
+	panic(yamlError{err})
+}
+
+func failf(format string, args ...interface{}) {
+	panic(yamlError{fmt.Errorf("yaml: "+format, args...)})
+}
+
+// A TypeError is returned by Unmarshal when one or more fields in
+// the YAML document cannot be properly decoded into the requested
+// types. When this error is returned, the value is still
+// unmarshaled partially.
+type TypeError struct {
+	Errors []string
+}
+
+func (e *TypeError) Error() string {
+	return fmt.Sprintf("yaml: unmarshal errors:\n  %s", strings.Join(e.Errors, "\n  "))
+}
+
+type Kind uint32
+
+const (
+	DocumentNode Kind = 1 << iota
+	SequenceNode
+	MappingNode
+	ScalarNode
+	AliasNode
+)
+
+type Style uint32
+
+const (
+	TaggedStyle Style = 1 << iota
+	DoubleQuotedStyle
+	SingleQuotedStyle
+	LiteralStyle
+	FoldedStyle
+	FlowStyle
+)
+
+// Node represents an element in the YAML document hierarchy. While documents
+// are typically encoded and decoded into higher level types, such as structs
+// and maps, Node is an intermediate representation that allows detailed
+// control over the content being decoded or encoded.
+//
+// It's worth noting that although Node offers access into details such as
+// line numbers, colums, and comments, the content when re-encoded will not
+// have its original textual representation preserved. An effort is made to
+// render the data plesantly, and to preserve comments near the data they
+// describe, though.
+//
+// Values that make use of the Node type interact with the yaml package in the
+// same way any other type would do, by encoding and decoding yaml data
+// directly or indirectly into them.
+//
+// For example:
+//
+//     var person struct {
+//             Name    string
+//             Address yaml.Node
+//     }
+//     err := yaml.Unmarshal(data, &person)
+// 
+// Or by itself:
+//
+//     var person Node
+//     err := yaml.Unmarshal(data, &person)
+//
+type Node struct {
+	// Kind defines whether the node is a document, a mapping, a sequence,
+	// a scalar value, or an alias to another node. The specific data type of
+	// scalar nodes may be obtained via the ShortTag and LongTag methods.
+	Kind  Kind
+
+	// Style allows customizing the apperance of the node in the tree.
+	Style Style
+
+	// Tag holds the YAML tag defining the data type for the value.
+	// When decoding, this field will always be set to the resolved tag,
+	// even when it wasn't explicitly provided in the YAML content.
+	// When encoding, if this field is unset the value type will be
+	// implied from the node properties, and if it is set, it will only
+	// be serialized into the representation if TaggedStyle is used or
+	// the implicit tag diverges from the provided one.
+	Tag string
+
+	// Value holds the unescaped and unquoted represenation of the value.
+	Value string
+
+	// Anchor holds the anchor name for this node, which allows aliases to point to it.
+	Anchor string
+
+	// Alias holds the node that this alias points to. Only valid when Kind is AliasNode.
+	Alias *Node
+
+	// Content holds contained nodes for documents, mappings, and sequences.
+	Content []*Node
+
+	// HeadComment holds any comments in the lines preceding the node and
+	// not separated by an empty line.
+	HeadComment string
+
+	// LineComment holds any comments at the end of the line where the node is in.
+	LineComment string
+
+	// FootComment holds any comments following the node and before empty lines.
+	FootComment string
+
+	// Line and Column hold the node position in the decoded YAML text.
+	// These fields are not respected when encoding the node.
+	Line   int
+	Column int
+}
+
+// IsZero returns whether the node has all of its fields unset.
+func (n *Node) IsZero() bool {
+	return n.Kind == 0 && n.Style == 0 && n.Tag == "" && n.Value == "" && n.Anchor == "" && n.Alias == nil && n.Content == nil &&
+		n.HeadComment == "" && n.LineComment == "" && n.FootComment == "" && n.Line == 0 && n.Column == 0
+}
+
+
+// LongTag returns the long form of the tag that indicates the data type for
+// the node. If the Tag field isn't explicitly defined, one will be computed
+// based on the node properties.
+func (n *Node) LongTag() string {
+	return longTag(n.ShortTag())
+}
+
+// ShortTag returns the short form of the YAML tag that indicates data type for
+// the node. If the Tag field isn't explicitly defined, one will be computed
+// based on the node properties.
+func (n *Node) ShortTag() string {
+	if n.indicatedString() {
+		return strTag
+	}
+	if n.Tag == "" || n.Tag == "!" {
+		switch n.Kind {
+		case MappingNode:
+			return mapTag
+		case SequenceNode:
+			return seqTag
+		case AliasNode:
+			if n.Alias != nil {
+				return n.Alias.ShortTag()
+			}
+		case ScalarNode:
+			tag, _ := resolve("", n.Value)
+			return tag
+		case 0:
+			// Special case to make the zero value convenient.
+			if n.IsZero() {
+				return nullTag
+			}
+		}
+		return ""
+	}
+	return shortTag(n.Tag)
+}
+
+func (n *Node) indicatedString() bool {
+	return n.Kind == ScalarNode &&
+		(shortTag(n.Tag) == strTag ||
+			(n.Tag == "" || n.Tag == "!") && n.Style&(SingleQuotedStyle|DoubleQuotedStyle|LiteralStyle|FoldedStyle) != 0)
+}
+
+// SetString is a convenience function that sets the node to a string value
+// and defines its style in a pleasant way depending on its content.
+func (n *Node) SetString(s string) {
+	n.Kind = ScalarNode
+	if utf8.ValidString(s) {
+		n.Value = s
+		n.Tag = strTag
+	} else {
+		n.Value = encodeBase64(s)
+		n.Tag = binaryTag
+	}
+	if strings.Contains(n.Value, "\n") {
+		n.Style = LiteralStyle
+	}
+}
+
+// --------------------------------------------------------------------------
+// Maintain a mapping of keys to structure field indexes
+
+// The code in this section was copied from mgo/bson.
+
+// structInfo holds details for the serialization of fields of
+// a given struct.
+type structInfo struct {
+	FieldsMap  map[string]fieldInfo
+	FieldsList []fieldInfo
+
+	// InlineMap is the number of the field in the struct that
+	// contains an ,inline map, or -1 if there's none.
+	InlineMap int
+
+	// InlineUnmarshalers holds indexes to inlined fields that
+	// contain unmarshaler values.
+	InlineUnmarshalers [][]int
+}
+
+type fieldInfo struct {
+	Key       string
+	Num       int
+	OmitEmpty bool
+	Flow      bool
+	// Id holds the unique field identifier, so we can cheaply
+	// check for field duplicates without maintaining an extra map.
+	Id int
+
+	// Inline holds the field index if the field is part of an inlined struct.
+	Inline []int
+}
+
+var structMap = make(map[reflect.Type]*structInfo)
+var fieldMapMutex sync.RWMutex
+var unmarshalerType reflect.Type
+
+func init() {
+	var v Unmarshaler
+	unmarshalerType = reflect.ValueOf(&v).Elem().Type()
+}
+
+func getStructInfo(st reflect.Type) (*structInfo, error) {
+	fieldMapMutex.RLock()
+	sinfo, found := structMap[st]
+	fieldMapMutex.RUnlock()
+	if found {
+		return sinfo, nil
+	}
+
+	n := st.NumField()
+	fieldsMap := make(map[string]fieldInfo)
+	fieldsList := make([]fieldInfo, 0, n)
+	inlineMap := -1
+	inlineUnmarshalers := [][]int(nil)
+	for i := 0; i != n; i++ {
+		field := st.Field(i)
+		if field.PkgPath != "" && !field.Anonymous {
+			continue // Private field
+		}
+
+		info := fieldInfo{Num: i}
+
+		tag := field.Tag.Get("yaml")
+		if tag == "" && strings.Index(string(field.Tag), ":") < 0 {
+			tag = string(field.Tag)
+		}
+		if tag == "-" {
+			continue
+		}
+
+		inline := false
+		fields := strings.Split(tag, ",")
+		if len(fields) > 1 {
+			for _, flag := range fields[1:] {
+				switch flag {
+				case "omitempty":
+					info.OmitEmpty = true
+				case "flow":
+					info.Flow = true
+				case "inline":
+					inline = true
+				default:
+					return nil, errors.New(fmt.Sprintf("unsupported flag %q in tag %q of type %s", flag, tag, st))
+				}
+			}
+			tag = fields[0]
+		}
+
+		if inline {
+			switch field.Type.Kind() {
+			case reflect.Map:
+				if inlineMap >= 0 {
+					return nil, errors.New("multiple ,inline maps in struct " + st.String())
+				}
+				if field.Type.Key() != reflect.TypeOf("") {
+					return nil, errors.New("option ,inline needs a map with string keys in struct " + st.String())
+				}
+				inlineMap = info.Num
+			case reflect.Struct, reflect.Ptr:
+				ftype := field.Type
+				for ftype.Kind() == reflect.Ptr {
+					ftype = ftype.Elem()
+				}
+				if ftype.Kind() != reflect.Struct {
+					return nil, errors.New("option ,inline may only be used on a struct or map field")
+				}
+				if reflect.PtrTo(ftype).Implements(unmarshalerType) {
+					inlineUnmarshalers = append(inlineUnmarshalers, []int{i})
+				} else {
+					sinfo, err := getStructInfo(ftype)
+					if err != nil {
+						return nil, err
+					}
+					for _, index := range sinfo.InlineUnmarshalers {
+						inlineUnmarshalers = append(inlineUnmarshalers, append([]int{i}, index...))
+					}
+					for _, finfo := range sinfo.FieldsList {
+						if _, found := fieldsMap[finfo.Key]; found {
+							msg := "duplicated key '" + finfo.Key + "' in struct " + st.String()
+							return nil, errors.New(msg)
+						}
+						if finfo.Inline == nil {
+							finfo.Inline = []int{i, finfo.Num}
+						} else {
+							finfo.Inline = append([]int{i}, finfo.Inline...)
+						}
+						finfo.Id = len(fieldsList)
+						fieldsMap[finfo.Key] = finfo
+						fieldsList = append(fieldsList, finfo)
+					}
+				}
+			default:
+				return nil, errors.New("option ,inline may only be used on a struct or map field")
+			}
+			continue
+		}
+
+		if tag != "" {
+			info.Key = tag
+		} else {
+			info.Key = strings.ToLower(field.Name)
+		}
+
+		if _, found = fieldsMap[info.Key]; found {
+			msg := "duplicated key '" + info.Key + "' in struct " + st.String()
+			return nil, errors.New(msg)
+		}
+
+		info.Id = len(fieldsList)
+		fieldsList = append(fieldsList, info)
+		fieldsMap[info.Key] = info
+	}
+
+	sinfo = &structInfo{
+		FieldsMap:          fieldsMap,
+		FieldsList:         fieldsList,
+		InlineMap:          inlineMap,
+		InlineUnmarshalers: inlineUnmarshalers,
+	}
+
+	fieldMapMutex.Lock()
+	structMap[st] = sinfo
+	fieldMapMutex.Unlock()
+	return sinfo, nil
+}
+
+// IsZeroer is used to check whether an object is zero to
+// determine whether it should be omitted when marshaling
+// with the omitempty flag. One notable implementation
+// is time.Time.
+type IsZeroer interface {
+	IsZero() bool
+}
+
+func isZero(v reflect.Value) bool {
+	kind := v.Kind()
+	if z, ok := v.Interface().(IsZeroer); ok {
+		if (kind == reflect.Ptr || kind == reflect.Interface) && v.IsNil() {
+			return true
+		}
+		return z.IsZero()
+	}
+	switch kind {
+	case reflect.String:
+		return len(v.String()) == 0
+	case reflect.Interface, reflect.Ptr:
+		return v.IsNil()
+	case reflect.Slice:
+		return v.Len() == 0
+	case reflect.Map:
+		return v.Len() == 0
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return v.Uint() == 0
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Struct:
+		vt := v.Type()
+		for i := v.NumField() - 1; i >= 0; i-- {
+			if vt.Field(i).PkgPath != "" {
+				continue // Private field
+			}
+			if !isZero(v.Field(i)) {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}

vendor/gopkg.in/yaml.v3/yamlh.go

@@ -0,0 +1,807 @@
+//
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+import (
+	"fmt"
+	"io"
+)
+
+// The version directive data.
+type yaml_version_directive_t struct {
+	major int8 // The major version number.
+	minor int8 // The minor version number.
+}
+
+// The tag directive data.
+type yaml_tag_directive_t struct {
+	handle []byte // The tag handle.
+	prefix []byte // The tag prefix.
+}
+
+type yaml_encoding_t int
+
+// The stream encoding.
+const (
+	// Let the parser choose the encoding.
+	yaml_ANY_ENCODING yaml_encoding_t = iota
+
+	yaml_UTF8_ENCODING    // The default UTF-8 encoding.
+	yaml_UTF16LE_ENCODING // The UTF-16-LE encoding with BOM.
+	yaml_UTF16BE_ENCODING // The UTF-16-BE encoding with BOM.
+)
+
+type yaml_break_t int
+
+// Line break types.
+const (
+	// Let the parser choose the break type.
+	yaml_ANY_BREAK yaml_break_t = iota
+
+	yaml_CR_BREAK   // Use CR for line breaks (Mac style).
+	yaml_LN_BREAK   // Use LN for line breaks (Unix style).
+	yaml_CRLN_BREAK // Use CR LN for line breaks (DOS style).
+)
+
+type yaml_error_type_t int
+
+// Many bad things could happen with the parser and emitter.
+const (
+	// No error is produced.
+	yaml_NO_ERROR yaml_error_type_t = iota
+
+	yaml_MEMORY_ERROR   // Cannot allocate or reallocate a block of memory.
+	yaml_READER_ERROR   // Cannot read or decode the input stream.
+	yaml_SCANNER_ERROR  // Cannot scan the input stream.
+	yaml_PARSER_ERROR   // Cannot parse the input stream.
+	yaml_COMPOSER_ERROR // Cannot compose a YAML document.
+	yaml_WRITER_ERROR   // Cannot write to the output stream.
+	yaml_EMITTER_ERROR  // Cannot emit a YAML stream.
+)
+
+// The pointer position.
+type yaml_mark_t struct {
+	index  int // The position index.
+	line   int // The position line.
+	column int // The position column.
+}
+
+// Node Styles
+
+type yaml_style_t int8
+
+type yaml_scalar_style_t yaml_style_t
+
+// Scalar styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SCALAR_STYLE yaml_scalar_style_t = 0
+
+	yaml_PLAIN_SCALAR_STYLE         yaml_scalar_style_t = 1 << iota // The plain scalar style.
+	yaml_SINGLE_QUOTED_SCALAR_STYLE                                 // The single-quoted scalar style.
+	yaml_DOUBLE_QUOTED_SCALAR_STYLE                                 // The double-quoted scalar style.
+	yaml_LITERAL_SCALAR_STYLE                                       // The literal scalar style.
+	yaml_FOLDED_SCALAR_STYLE                                        // The folded scalar style.
+)
+
+type yaml_sequence_style_t yaml_style_t
+
+// Sequence styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_SEQUENCE_STYLE yaml_sequence_style_t = iota
+
+	yaml_BLOCK_SEQUENCE_STYLE // The block sequence style.
+	yaml_FLOW_SEQUENCE_STYLE  // The flow sequence style.
+)
+
+type yaml_mapping_style_t yaml_style_t
+
+// Mapping styles.
+const (
+	// Let the emitter choose the style.
+	yaml_ANY_MAPPING_STYLE yaml_mapping_style_t = iota
+
+	yaml_BLOCK_MAPPING_STYLE // The block mapping style.
+	yaml_FLOW_MAPPING_STYLE  // The flow mapping style.
+)
+
+// Tokens
+
+type yaml_token_type_t int
+
+// Token types.
+const (
+	// An empty token.
+	yaml_NO_TOKEN yaml_token_type_t = iota
+
+	yaml_STREAM_START_TOKEN // A STREAM-START token.
+	yaml_STREAM_END_TOKEN   // A STREAM-END token.
+
+	yaml_VERSION_DIRECTIVE_TOKEN // A VERSION-DIRECTIVE token.
+	yaml_TAG_DIRECTIVE_TOKEN     // A TAG-DIRECTIVE token.
+	yaml_DOCUMENT_START_TOKEN    // A DOCUMENT-START token.
+	yaml_DOCUMENT_END_TOKEN      // A DOCUMENT-END token.
+
+	yaml_BLOCK_SEQUENCE_START_TOKEN // A BLOCK-SEQUENCE-START token.
+	yaml_BLOCK_MAPPING_START_TOKEN  // A BLOCK-SEQUENCE-END token.
+	yaml_BLOCK_END_TOKEN            // A BLOCK-END token.
+
+	yaml_FLOW_SEQUENCE_START_TOKEN // A FLOW-SEQUENCE-START token.
+	yaml_FLOW_SEQUENCE_END_TOKEN   // A FLOW-SEQUENCE-END token.
+	yaml_FLOW_MAPPING_START_TOKEN  // A FLOW-MAPPING-START token.
+	yaml_FLOW_MAPPING_END_TOKEN    // A FLOW-MAPPING-END token.
+
+	yaml_BLOCK_ENTRY_TOKEN // A BLOCK-ENTRY token.
+	yaml_FLOW_ENTRY_TOKEN  // A FLOW-ENTRY token.
+	yaml_KEY_TOKEN         // A KEY token.
+	yaml_VALUE_TOKEN       // A VALUE token.
+
+	yaml_ALIAS_TOKEN  // An ALIAS token.
+	yaml_ANCHOR_TOKEN // An ANCHOR token.
+	yaml_TAG_TOKEN    // A TAG token.
+	yaml_SCALAR_TOKEN // A SCALAR token.
+)
+
+func (tt yaml_token_type_t) String() string {
+	switch tt {
+	case yaml_NO_TOKEN:
+		return "yaml_NO_TOKEN"
+	case yaml_STREAM_START_TOKEN:
+		return "yaml_STREAM_START_TOKEN"
+	case yaml_STREAM_END_TOKEN:
+		return "yaml_STREAM_END_TOKEN"
+	case yaml_VERSION_DIRECTIVE_TOKEN:
+		return "yaml_VERSION_DIRECTIVE_TOKEN"
+	case yaml_TAG_DIRECTIVE_TOKEN:
+		return "yaml_TAG_DIRECTIVE_TOKEN"
+	case yaml_DOCUMENT_START_TOKEN:
+		return "yaml_DOCUMENT_START_TOKEN"
+	case yaml_DOCUMENT_END_TOKEN:
+		return "yaml_DOCUMENT_END_TOKEN"
+	case yaml_BLOCK_SEQUENCE_START_TOKEN:
+		return "yaml_BLOCK_SEQUENCE_START_TOKEN"
+	case yaml_BLOCK_MAPPING_START_TOKEN:
+		return "yaml_BLOCK_MAPPING_START_TOKEN"
+	case yaml_BLOCK_END_TOKEN:
+		return "yaml_BLOCK_END_TOKEN"
+	case yaml_FLOW_SEQUENCE_START_TOKEN:
+		return "yaml_FLOW_SEQUENCE_START_TOKEN"
+	case yaml_FLOW_SEQUENCE_END_TOKEN:
+		return "yaml_FLOW_SEQUENCE_END_TOKEN"
+	case yaml_FLOW_MAPPING_START_TOKEN:
+		return "yaml_FLOW_MAPPING_START_TOKEN"
+	case yaml_FLOW_MAPPING_END_TOKEN:
+		return "yaml_FLOW_MAPPING_END_TOKEN"
+	case yaml_BLOCK_ENTRY_TOKEN:
+		return "yaml_BLOCK_ENTRY_TOKEN"
+	case yaml_FLOW_ENTRY_TOKEN:
+		return "yaml_FLOW_ENTRY_TOKEN"
+	case yaml_KEY_TOKEN:
+		return "yaml_KEY_TOKEN"
+	case yaml_VALUE_TOKEN:
+		return "yaml_VALUE_TOKEN"
+	case yaml_ALIAS_TOKEN:
+		return "yaml_ALIAS_TOKEN"
+	case yaml_ANCHOR_TOKEN:
+		return "yaml_ANCHOR_TOKEN"
+	case yaml_TAG_TOKEN:
+		return "yaml_TAG_TOKEN"
+	case yaml_SCALAR_TOKEN:
+		return "yaml_SCALAR_TOKEN"
+	}
+	return "<unknown token>"
+}
+
+// The token structure.
+type yaml_token_t struct {
+	// The token type.
+	typ yaml_token_type_t
+
+	// The start/end of the token.
+	start_mark, end_mark yaml_mark_t
+
+	// The stream encoding (for yaml_STREAM_START_TOKEN).
+	encoding yaml_encoding_t
+
+	// The alias/anchor/scalar value or tag/tag directive handle
+	// (for yaml_ALIAS_TOKEN, yaml_ANCHOR_TOKEN, yaml_SCALAR_TOKEN, yaml_TAG_TOKEN, yaml_TAG_DIRECTIVE_TOKEN).
+	value []byte
+
+	// The tag suffix (for yaml_TAG_TOKEN).
+	suffix []byte
+
+	// The tag directive prefix (for yaml_TAG_DIRECTIVE_TOKEN).
+	prefix []byte
+
+	// The scalar style (for yaml_SCALAR_TOKEN).
+	style yaml_scalar_style_t
+
+	// The version directive major/minor (for yaml_VERSION_DIRECTIVE_TOKEN).
+	major, minor int8
+}
+
+// Events
+
+type yaml_event_type_t int8
+
+// Event types.
+const (
+	// An empty event.
+	yaml_NO_EVENT yaml_event_type_t = iota
+
+	yaml_STREAM_START_EVENT   // A STREAM-START event.
+	yaml_STREAM_END_EVENT     // A STREAM-END event.
+	yaml_DOCUMENT_START_EVENT // A DOCUMENT-START event.
+	yaml_DOCUMENT_END_EVENT   // A DOCUMENT-END event.
+	yaml_ALIAS_EVENT          // An ALIAS event.
+	yaml_SCALAR_EVENT         // A SCALAR event.
+	yaml_SEQUENCE_START_EVENT // A SEQUENCE-START event.
+	yaml_SEQUENCE_END_EVENT   // A SEQUENCE-END event.
+	yaml_MAPPING_START_EVENT  // A MAPPING-START event.
+	yaml_MAPPING_END_EVENT    // A MAPPING-END event.
+	yaml_TAIL_COMMENT_EVENT
+)
+
+var eventStrings = []string{
+	yaml_NO_EVENT:             "none",
+	yaml_STREAM_START_EVENT:   "stream start",
+	yaml_STREAM_END_EVENT:     "stream end",
+	yaml_DOCUMENT_START_EVENT: "document start",
+	yaml_DOCUMENT_END_EVENT:   "document end",
+	yaml_ALIAS_EVENT:          "alias",
+	yaml_SCALAR_EVENT:         "scalar",
+	yaml_SEQUENCE_START_EVENT: "sequence start",
+	yaml_SEQUENCE_END_EVENT:   "sequence end",
+	yaml_MAPPING_START_EVENT:  "mapping start",
+	yaml_MAPPING_END_EVENT:    "mapping end",
+	yaml_TAIL_COMMENT_EVENT:   "tail comment",
+}
+
+func (e yaml_event_type_t) String() string {
+	if e < 0 || int(e) >= len(eventStrings) {
+		return fmt.Sprintf("unknown event %d", e)
+	}
+	return eventStrings[e]
+}
+
+// The event structure.
+type yaml_event_t struct {
+
+	// The event type.
+	typ yaml_event_type_t
+
+	// The start and end of the event.
+	start_mark, end_mark yaml_mark_t
+
+	// The document encoding (for yaml_STREAM_START_EVENT).
+	encoding yaml_encoding_t
+
+	// The version directive (for yaml_DOCUMENT_START_EVENT).
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives (for yaml_DOCUMENT_START_EVENT).
+	tag_directives []yaml_tag_directive_t
+
+	// The comments
+	head_comment []byte
+	line_comment []byte
+	foot_comment []byte
+	tail_comment []byte
+
+	// The anchor (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_ALIAS_EVENT).
+	anchor []byte
+
+	// The tag (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	tag []byte
+
+	// The scalar value (for yaml_SCALAR_EVENT).
+	value []byte
+
+	// Is the document start/end indicator implicit, or the tag optional?
+	// (for yaml_DOCUMENT_START_EVENT, yaml_DOCUMENT_END_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT, yaml_SCALAR_EVENT).
+	implicit bool
+
+	// Is the tag optional for any non-plain style? (for yaml_SCALAR_EVENT).
+	quoted_implicit bool
+
+	// The style (for yaml_SCALAR_EVENT, yaml_SEQUENCE_START_EVENT, yaml_MAPPING_START_EVENT).
+	style yaml_style_t
+}
+
+func (e *yaml_event_t) scalar_style() yaml_scalar_style_t     { return yaml_scalar_style_t(e.style) }
+func (e *yaml_event_t) sequence_style() yaml_sequence_style_t { return yaml_sequence_style_t(e.style) }
+func (e *yaml_event_t) mapping_style() yaml_mapping_style_t   { return yaml_mapping_style_t(e.style) }
+
+// Nodes
+
+const (
+	yaml_NULL_TAG      = "tag:yaml.org,2002:null"      // The tag !!null with the only possible value: null.
+	yaml_BOOL_TAG      = "tag:yaml.org,2002:bool"      // The tag !!bool with the values: true and false.
+	yaml_STR_TAG       = "tag:yaml.org,2002:str"       // The tag !!str for string values.
+	yaml_INT_TAG       = "tag:yaml.org,2002:int"       // The tag !!int for integer values.
+	yaml_FLOAT_TAG     = "tag:yaml.org,2002:float"     // The tag !!float for float values.
+	yaml_TIMESTAMP_TAG = "tag:yaml.org,2002:timestamp" // The tag !!timestamp for date and time values.
+
+	yaml_SEQ_TAG = "tag:yaml.org,2002:seq" // The tag !!seq is used to denote sequences.
+	yaml_MAP_TAG = "tag:yaml.org,2002:map" // The tag !!map is used to denote mapping.
+
+	// Not in original libyaml.
+	yaml_BINARY_TAG = "tag:yaml.org,2002:binary"
+	yaml_MERGE_TAG  = "tag:yaml.org,2002:merge"
+
+	yaml_DEFAULT_SCALAR_TAG   = yaml_STR_TAG // The default scalar tag is !!str.
+	yaml_DEFAULT_SEQUENCE_TAG = yaml_SEQ_TAG // The default sequence tag is !!seq.
+	yaml_DEFAULT_MAPPING_TAG  = yaml_MAP_TAG // The default mapping tag is !!map.
+)
+
+type yaml_node_type_t int
+
+// Node types.
+const (
+	// An empty node.
+	yaml_NO_NODE yaml_node_type_t = iota
+
+	yaml_SCALAR_NODE   // A scalar node.
+	yaml_SEQUENCE_NODE // A sequence node.
+	yaml_MAPPING_NODE  // A mapping node.
+)
+
+// An element of a sequence node.
+type yaml_node_item_t int
+
+// An element of a mapping node.
+type yaml_node_pair_t struct {
+	key   int // The key of the element.
+	value int // The value of the element.
+}
+
+// The node structure.
+type yaml_node_t struct {
+	typ yaml_node_type_t // The node type.
+	tag []byte           // The node tag.
+
+	// The node data.
+
+	// The scalar parameters (for yaml_SCALAR_NODE).
+	scalar struct {
+		value  []byte              // The scalar value.
+		length int                 // The length of the scalar value.
+		style  yaml_scalar_style_t // The scalar style.
+	}
+
+	// The sequence parameters (for YAML_SEQUENCE_NODE).
+	sequence struct {
+		items_data []yaml_node_item_t    // The stack of sequence items.
+		style      yaml_sequence_style_t // The sequence style.
+	}
+
+	// The mapping parameters (for yaml_MAPPING_NODE).
+	mapping struct {
+		pairs_data  []yaml_node_pair_t   // The stack of mapping pairs (key, value).
+		pairs_start *yaml_node_pair_t    // The beginning of the stack.
+		pairs_end   *yaml_node_pair_t    // The end of the stack.
+		pairs_top   *yaml_node_pair_t    // The top of the stack.
+		style       yaml_mapping_style_t // The mapping style.
+	}
+
+	start_mark yaml_mark_t // The beginning of the node.
+	end_mark   yaml_mark_t // The end of the node.
+
+}
+
+// The document structure.
+type yaml_document_t struct {
+
+	// The document nodes.
+	nodes []yaml_node_t
+
+	// The version directive.
+	version_directive *yaml_version_directive_t
+
+	// The list of tag directives.
+	tag_directives_data  []yaml_tag_directive_t
+	tag_directives_start int // The beginning of the tag directives list.
+	tag_directives_end   int // The end of the tag directives list.
+
+	start_implicit int // Is the document start indicator implicit?
+	end_implicit   int // Is the document end indicator implicit?
+
+	// The start/end of the document.
+	start_mark, end_mark yaml_mark_t
+}
+
+// The prototype of a read handler.
+//
+// The read handler is called when the parser needs to read more bytes from the
+// source. The handler should write not more than size bytes to the buffer.
+// The number of written bytes should be set to the size_read variable.
+//
+// [in,out]   data        A pointer to an application data specified by
+//                        yaml_parser_set_input().
+// [out]      buffer      The buffer to write the data from the source.
+// [in]       size        The size of the buffer.
+// [out]      size_read   The actual number of bytes read from the source.
+//
+// On success, the handler should return 1.  If the handler failed,
+// the returned value should be 0. On EOF, the handler should set the
+// size_read to 0 and return 1.
+type yaml_read_handler_t func(parser *yaml_parser_t, buffer []byte) (n int, err error)
+
+// This structure holds information about a potential simple key.
+type yaml_simple_key_t struct {
+	possible     bool        // Is a simple key possible?
+	required     bool        // Is a simple key required?
+	token_number int         // The number of the token.
+	mark         yaml_mark_t // The position mark.
+}
+
+// The states of the parser.
+type yaml_parser_state_t int
+
+const (
+	yaml_PARSE_STREAM_START_STATE yaml_parser_state_t = iota
+
+	yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE           // Expect the beginning of an implicit document.
+	yaml_PARSE_DOCUMENT_START_STATE                    // Expect DOCUMENT-START.
+	yaml_PARSE_DOCUMENT_CONTENT_STATE                  // Expect the content of a document.
+	yaml_PARSE_DOCUMENT_END_STATE                      // Expect DOCUMENT-END.
+	yaml_PARSE_BLOCK_NODE_STATE                        // Expect a block node.
+	yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE // Expect a block node or indentless sequence.
+	yaml_PARSE_FLOW_NODE_STATE                         // Expect a flow node.
+	yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE        // Expect the first entry of a block sequence.
+	yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE              // Expect an entry of a block sequence.
+	yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE         // Expect an entry of an indentless sequence.
+	yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE           // Expect the first key of a block mapping.
+	yaml_PARSE_BLOCK_MAPPING_KEY_STATE                 // Expect a block mapping key.
+	yaml_PARSE_BLOCK_MAPPING_VALUE_STATE               // Expect a block mapping value.
+	yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE         // Expect the first entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE               // Expect an entry of a flow sequence.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE   // Expect a key of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE // Expect a value of an ordered mapping.
+	yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE   // Expect the and of an ordered mapping entry.
+	yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE            // Expect the first key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_KEY_STATE                  // Expect a key of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_VALUE_STATE                // Expect a value of a flow mapping.
+	yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE          // Expect an empty value of a flow mapping.
+	yaml_PARSE_END_STATE                               // Expect nothing.
+)
+
+func (ps yaml_parser_state_t) String() string {
+	switch ps {
+	case yaml_PARSE_STREAM_START_STATE:
+		return "yaml_PARSE_STREAM_START_STATE"
+	case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
+		return "yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_START_STATE:
+		return "yaml_PARSE_DOCUMENT_START_STATE"
+	case yaml_PARSE_DOCUMENT_CONTENT_STATE:
+		return "yaml_PARSE_DOCUMENT_CONTENT_STATE"
+	case yaml_PARSE_DOCUMENT_END_STATE:
+		return "yaml_PARSE_DOCUMENT_END_STATE"
+	case yaml_PARSE_BLOCK_NODE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_STATE"
+	case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
+		return "yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE"
+	case yaml_PARSE_FLOW_NODE_STATE:
+		return "yaml_PARSE_FLOW_NODE_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_KEY_STATE"
+	case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_BLOCK_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
+		return "yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE"
+	case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_KEY_STATE"
+	case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_VALUE_STATE"
+	case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
+		return "yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE"
+	case yaml_PARSE_END_STATE:
+		return "yaml_PARSE_END_STATE"
+	}
+	return "<unknown parser state>"
+}
+
+// This structure holds aliases data.
+type yaml_alias_data_t struct {
+	anchor []byte      // The anchor.
+	index  int         // The node id.
+	mark   yaml_mark_t // The anchor mark.
+}
+
+// The parser structure.
+//
+// All members are internal. Manage the structure using the
+// yaml_parser_ family of functions.
+type yaml_parser_t struct {
+
+	// Error handling
+
+	error yaml_error_type_t // Error type.
+
+	problem string // Error description.
+
+	// The byte about which the problem occurred.
+	problem_offset int
+	problem_value  int
+	problem_mark   yaml_mark_t
+
+	// The error context.
+	context      string
+	context_mark yaml_mark_t
+
+	// Reader stuff
+
+	read_handler yaml_read_handler_t // Read handler.
+
+	input_reader io.Reader // File input data.
+	input        []byte    // String input data.
+	input_pos    int
+
+	eof bool // EOF flag
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	unread int // The number of unread characters in the buffer.
+
+	newlines int // The number of line breaks since last non-break/non-blank character
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The input encoding.
+
+	offset int         // The offset of the current position (in bytes).
+	mark   yaml_mark_t // The mark of the current position.
+
+	// Comments
+
+	head_comment []byte // The current head comments
+	line_comment []byte // The current line comments
+	foot_comment []byte // The current foot comments
+	tail_comment []byte // Foot comment that happens at the end of a block.
+	stem_comment []byte // Comment in item preceding a nested structure (list inside list item, etc)
+
+	comments      []yaml_comment_t // The folded comments for all parsed tokens
+	comments_head int
+
+	// Scanner stuff
+
+	stream_start_produced bool // Have we started to scan the input stream?
+	stream_end_produced   bool // Have we reached the end of the input stream?
+
+	flow_level int // The number of unclosed '[' and '{' indicators.
+
+	tokens          []yaml_token_t // The tokens queue.
+	tokens_head     int            // The head of the tokens queue.
+	tokens_parsed   int            // The number of tokens fetched from the queue.
+	token_available bool           // Does the tokens queue contain a token ready for dequeueing.
+
+	indent  int   // The current indentation level.
+	indents []int // The indentation levels stack.
+
+	simple_key_allowed bool                // May a simple key occur at the current position?
+	simple_keys        []yaml_simple_key_t // The stack of simple keys.
+	simple_keys_by_tok map[int]int         // possible simple_key indexes indexed by token_number
+
+	// Parser stuff
+
+	state          yaml_parser_state_t    // The current parser state.
+	states         []yaml_parser_state_t  // The parser states stack.
+	marks          []yaml_mark_t          // The stack of marks.
+	tag_directives []yaml_tag_directive_t // The list of TAG directives.
+
+	// Dumper stuff
+
+	aliases []yaml_alias_data_t // The alias data.
+
+	document *yaml_document_t // The currently parsed document.
+}
+
+type yaml_comment_t struct {
+
+	scan_mark  yaml_mark_t // Position where scanning for comments started
+	token_mark yaml_mark_t // Position after which tokens will be associated with this comment
+	start_mark yaml_mark_t // Position of '#' comment mark
+	end_mark   yaml_mark_t // Position where comment terminated
+
+	head []byte
+	line []byte
+	foot []byte
+}
+
+// Emitter Definitions
+
+// The prototype of a write handler.
+//
+// The write handler is called when the emitter needs to flush the accumulated
+// characters to the output.  The handler should write @a size bytes of the
+// @a buffer to the output.
+//
+// @param[in,out]   data        A pointer to an application data specified by
+//                              yaml_emitter_set_output().
+// @param[in]       buffer      The buffer with bytes to be written.
+// @param[in]       size        The size of the buffer.
+//
+// @returns On success, the handler should return @c 1.  If the handler failed,
+// the returned value should be @c 0.
+//
+type yaml_write_handler_t func(emitter *yaml_emitter_t, buffer []byte) error
+
+type yaml_emitter_state_t int
+
+// The emitter states.
+const (
+	// Expect STREAM-START.
+	yaml_EMIT_STREAM_START_STATE yaml_emitter_state_t = iota
+
+	yaml_EMIT_FIRST_DOCUMENT_START_STATE       // Expect the first DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_START_STATE             // Expect DOCUMENT-START or STREAM-END.
+	yaml_EMIT_DOCUMENT_CONTENT_STATE           // Expect the content of a document.
+	yaml_EMIT_DOCUMENT_END_STATE               // Expect DOCUMENT-END.
+	yaml_EMIT_FLOW_SEQUENCE_FIRST_ITEM_STATE   // Expect the first item of a flow sequence.
+	yaml_EMIT_FLOW_SEQUENCE_TRAIL_ITEM_STATE   // Expect the next item of a flow sequence, with the comma already written out
+	yaml_EMIT_FLOW_SEQUENCE_ITEM_STATE         // Expect an item of a flow sequence.
+	yaml_EMIT_FLOW_MAPPING_FIRST_KEY_STATE     // Expect the first key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_TRAIL_KEY_STATE     // Expect the next key of a flow mapping, with the comma already written out
+	yaml_EMIT_FLOW_MAPPING_KEY_STATE           // Expect a key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_SIMPLE_VALUE_STATE  // Expect a value for a simple key of a flow mapping.
+	yaml_EMIT_FLOW_MAPPING_VALUE_STATE         // Expect a value of a flow mapping.
+	yaml_EMIT_BLOCK_SEQUENCE_FIRST_ITEM_STATE  // Expect the first item of a block sequence.
+	yaml_EMIT_BLOCK_SEQUENCE_ITEM_STATE        // Expect an item of a block sequence.
+	yaml_EMIT_BLOCK_MAPPING_FIRST_KEY_STATE    // Expect the first key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_KEY_STATE          // Expect the key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_SIMPLE_VALUE_STATE // Expect a value for a simple key of a block mapping.
+	yaml_EMIT_BLOCK_MAPPING_VALUE_STATE        // Expect a value of a block mapping.
+	yaml_EMIT_END_STATE                        // Expect nothing.
+)
+
+// The emitter structure.
+//
+// All members are internal.  Manage the structure using the @c yaml_emitter_
+// family of functions.
+type yaml_emitter_t struct {
+
+	// Error handling
+
+	error   yaml_error_type_t // Error type.
+	problem string            // Error description.
+
+	// Writer stuff
+
+	write_handler yaml_write_handler_t // Write handler.
+
+	output_buffer *[]byte   // String output data.
+	output_writer io.Writer // File output data.
+
+	buffer     []byte // The working buffer.
+	buffer_pos int    // The current position of the buffer.
+
+	raw_buffer     []byte // The raw buffer.
+	raw_buffer_pos int    // The current position of the buffer.
+
+	encoding yaml_encoding_t // The stream encoding.
+
+	// Emitter stuff
+
+	canonical   bool         // If the output is in the canonical style?
+	best_indent int          // The number of indentation spaces.
+	best_width  int          // The preferred width of the output lines.
+	unicode     bool         // Allow unescaped non-ASCII characters?
+	line_break  yaml_break_t // The preferred line break.
+
+	state  yaml_emitter_state_t   // The current emitter state.
+	states []yaml_emitter_state_t // The stack of states.
+
+	events      []yaml_event_t // The event queue.
+	events_head int            // The head of the event queue.
+
+	indents []int // The stack of indentation levels.
+
+	tag_directives []yaml_tag_directive_t // The list of tag directives.
+
+	indent int // The current indentation level.
+
+	flow_level int // The current flow level.
+
+	root_context       bool // Is it the document root context?
+	sequence_context   bool // Is it a sequence context?
+	mapping_context    bool // Is it a mapping context?
+	simple_key_context bool // Is it a simple mapping key context?
+
+	line       int  // The current line.
+	column     int  // The current column.
+	whitespace bool // If the last character was a whitespace?
+	indention  bool // If the last character was an indentation character (' ', '-', '?', ':')?
+	open_ended bool // If an explicit document end is required?
+
+	space_above bool // Is there's an empty line above?
+	foot_indent int  // The indent used to write the foot comment above, or -1 if none.
+
+	// Anchor analysis.
+	anchor_data struct {
+		anchor []byte // The anchor value.
+		alias  bool   // Is it an alias?
+	}
+
+	// Tag analysis.
+	tag_data struct {
+		handle []byte // The tag handle.
+		suffix []byte // The tag suffix.
+	}
+
+	// Scalar analysis.
+	scalar_data struct {
+		value                 []byte              // The scalar value.
+		multiline             bool                // Does the scalar contain line breaks?
+		flow_plain_allowed    bool                // Can the scalar be expessed in the flow plain style?
+		block_plain_allowed   bool                // Can the scalar be expressed in the block plain style?
+		single_quoted_allowed bool                // Can the scalar be expressed in the single quoted style?
+		block_allowed         bool                // Can the scalar be expressed in the literal or folded styles?
+		style                 yaml_scalar_style_t // The output style.
+	}
+
+	// Comments
+	head_comment []byte
+	line_comment []byte
+	foot_comment []byte
+	tail_comment []byte
+
+	key_line_comment []byte
+
+	// Dumper stuff
+
+	opened bool // If the stream was already opened?
+	closed bool // If the stream was already closed?
+
+	// The information associated with the document nodes.
+	anchors *struct {
+		references int  // The number of references.
+		anchor     int  // The anchor id.
+		serialized bool // If the node has been emitted?
+	}
+
+	last_anchor_id int // The last assigned anchor id.
+
+	document *yaml_document_t // The currently emitted document.
+}

vendor/gopkg.in/yaml.v3/yamlprivateh.go

@@ -0,0 +1,198 @@
+// 
+// Copyright (c) 2011-2019 Canonical Ltd
+// Copyright (c) 2006-2010 Kirill Simonov
+// 
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+// of the Software, and to permit persons to whom the Software is furnished to do
+// so, subject to the following conditions:
+// 
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+// 
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package yaml
+
+const (
+	// The size of the input raw buffer.
+	input_raw_buffer_size = 512
+
+	// The size of the input buffer.
+	// It should be possible to decode the whole raw buffer.
+	input_buffer_size = input_raw_buffer_size * 3
+
+	// The size of the output buffer.
+	output_buffer_size = 128
+
+	// The size of the output raw buffer.
+	// It should be possible to encode the whole output buffer.
+	output_raw_buffer_size = (output_buffer_size*2 + 2)
+
+	// The size of other stacks and queues.
+	initial_stack_size  = 16
+	initial_queue_size  = 16
+	initial_string_size = 16
+)
+
+// Check if the character at the specified position is an alphabetical
+// character, a digit, '_', or '-'.
+func is_alpha(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'Z' || b[i] >= 'a' && b[i] <= 'z' || b[i] == '_' || b[i] == '-'
+}
+
+// Check if the character at the specified position is a digit.
+func is_digit(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9'
+}
+
+// Get the value of a digit.
+func as_digit(b []byte, i int) int {
+	return int(b[i]) - '0'
+}
+
+// Check if the character at the specified position is a hex-digit.
+func is_hex(b []byte, i int) bool {
+	return b[i] >= '0' && b[i] <= '9' || b[i] >= 'A' && b[i] <= 'F' || b[i] >= 'a' && b[i] <= 'f'
+}
+
+// Get the value of a hex-digit.
+func as_hex(b []byte, i int) int {
+	bi := b[i]
+	if bi >= 'A' && bi <= 'F' {
+		return int(bi) - 'A' + 10
+	}
+	if bi >= 'a' && bi <= 'f' {
+		return int(bi) - 'a' + 10
+	}
+	return int(bi) - '0'
+}
+
+// Check if the character is ASCII.
+func is_ascii(b []byte, i int) bool {
+	return b[i] <= 0x7F
+}
+
+// Check if the character at the start of the buffer can be printed unescaped.
+func is_printable(b []byte, i int) bool {
+	return ((b[i] == 0x0A) || // . == #x0A
+		(b[i] >= 0x20 && b[i] <= 0x7E) || // #x20 <= . <= #x7E
+		(b[i] == 0xC2 && b[i+1] >= 0xA0) || // #0xA0 <= . <= #xD7FF
+		(b[i] > 0xC2 && b[i] < 0xED) ||
+		(b[i] == 0xED && b[i+1] < 0xA0) ||
+		(b[i] == 0xEE) ||
+		(b[i] == 0xEF && // #xE000 <= . <= #xFFFD
+			!(b[i+1] == 0xBB && b[i+2] == 0xBF) && // && . != #xFEFF
+			!(b[i+1] == 0xBF && (b[i+2] == 0xBE || b[i+2] == 0xBF))))
+}
+
+// Check if the character at the specified position is NUL.
+func is_z(b []byte, i int) bool {
+	return b[i] == 0x00
+}
+
+// Check if the beginning of the buffer is a BOM.
+func is_bom(b []byte, i int) bool {
+	return b[0] == 0xEF && b[1] == 0xBB && b[2] == 0xBF
+}
+
+// Check if the character at the specified position is space.
+func is_space(b []byte, i int) bool {
+	return b[i] == ' '
+}
+
+// Check if the character at the specified position is tab.
+func is_tab(b []byte, i int) bool {
+	return b[i] == '\t'
+}
+
+// Check if the character at the specified position is blank (space or tab).
+func is_blank(b []byte, i int) bool {
+	//return is_space(b, i) || is_tab(b, i)
+	return b[i] == ' ' || b[i] == '\t'
+}
+
+// Check if the character at the specified position is a line break.
+func is_break(b []byte, i int) bool {
+	return (b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9) // PS (#x2029)
+}
+
+func is_crlf(b []byte, i int) bool {
+	return b[i] == '\r' && b[i+1] == '\n'
+}
+
+// Check if the character is a line break or NUL.
+func is_breakz(b []byte, i int) bool {
+	//return is_break(b, i) || is_z(b, i)
+	return (
+		// is_break:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		// is_z:
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, or NUL.
+func is_spacez(b []byte, i int) bool {
+	//return is_space(b, i) || is_breakz(b, i)
+	return (
+		// is_space:
+		b[i] == ' ' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Check if the character is a line break, space, tab, or NUL.
+func is_blankz(b []byte, i int) bool {
+	//return is_blank(b, i) || is_breakz(b, i)
+	return (
+		// is_blank:
+		b[i] == ' ' || b[i] == '\t' ||
+		// is_breakz:
+		b[i] == '\r' || // CR (#xD)
+		b[i] == '\n' || // LF (#xA)
+		b[i] == 0xC2 && b[i+1] == 0x85 || // NEL (#x85)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA8 || // LS (#x2028)
+		b[i] == 0xE2 && b[i+1] == 0x80 && b[i+2] == 0xA9 || // PS (#x2029)
+		b[i] == 0)
+}
+
+// Determine the width of the character.
+func width(b byte) int {
+	// Don't replace these by a switch without first
+	// confirming that it is being inlined.
+	if b&0x80 == 0x00 {
+		return 1
+	}
+	if b&0xE0 == 0xC0 {
+		return 2
+	}
+	if b&0xF0 == 0xE0 {
+		return 3
+	}
+	if b&0xF8 == 0xF0 {
+		return 4
+	}
+	return 0
+
+}

vendor/modules.txt

@@ -200,6 +200,17 @@ github.com/docker/go-units
 # github.com/ghodss/yaml v1.0.0
 ## explicit
 github.com/ghodss/yaml
+# github.com/go-imports-organizer/goio v1.3.1
+## explicit; go 1.19
+github.com/go-imports-organizer/goio
+github.com/go-imports-organizer/goio/pkg/api/v1alpha1
+github.com/go-imports-organizer/goio/pkg/config
+github.com/go-imports-organizer/goio/pkg/excludes
+github.com/go-imports-organizer/goio/pkg/groups
+github.com/go-imports-organizer/goio/pkg/imports
+github.com/go-imports-organizer/goio/pkg/module
+github.com/go-imports-organizer/goio/pkg/sorter
+github.com/go-imports-organizer/goio/pkg/version
 # github.com/go-logr/logr v1.2.3
 ## explicit; go 1.16
 github.com/go-logr/logr
@@ -340,8 +351,11 @@ go.opencensus.io/internal
 go.opencensus.io/trace
 go.opencensus.io/trace/internal
 go.opencensus.io/trace/tracestate
-# golang.org/x/mod v0.8.0
+# golang.org/x/mod v0.9.0
 ## explicit; go 1.17
+golang.org/x/mod/internal/lazyregexp
+golang.org/x/mod/modfile
+golang.org/x/mod/module
 golang.org/x/mod/semver
 # golang.org/x/net v0.8.0
 ## explicit; go 1.17
@@ -414,6 +428,9 @@ google.golang.org/protobuf/runtime/protoimpl
 # gopkg.in/yaml.v2 v2.4.0
 ## explicit; go 1.15
 gopkg.in/yaml.v2
+# gopkg.in/yaml.v3 v3.0.1
+## explicit
+gopkg.in/yaml.v3
 # k8s.io/klog/v2 v2.90.1
 ## explicit; go 1.13
 k8s.io/klog/v2