Merge pull request #15714 from lavalamp/go2idl.2

cmd/libs/go2idl/generator/default_generator.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"io"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/namer"
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+// DefaultGen implements a do-nothing Generator.
+//
+// It can be used to implement static content files.
+type DefaultGen struct {
+	// OptionalName, if present, will be used for the generator's name, and
+	// the filename (with ".go" appended).
+	OptionalName string
+
+	// OptionalBody, if present, will be used as the return from the "Init"
+	// method. This causes it to be static content for the entire file if
+	// no other generator touches the file.
+	OptionalBody []byte
+}
+
+func (d DefaultGen) Name() string                                        { return d.OptionalName }
+func (d DefaultGen) Filter(*Context, *types.Type) bool                   { return true }
+func (d DefaultGen) Namers(*Context) namer.NameSystems                   { return nil }
+func (d DefaultGen) Imports(*Context) []string                           { return []string{} }
+func (d DefaultGen) PackageVars(*Context) []string                       { return []string{} }
+func (d DefaultGen) PackageConsts(*Context) []string                     { return []string{} }
+func (d DefaultGen) GenerateType(*Context, *types.Type, io.Writer) error { return nil }
+func (d DefaultGen) Filename() string                                    { return d.OptionalName + ".go" }
+
+func (d DefaultGen) Init(c *Context, w io.Writer) error {
+	_, err := w.Write(d.OptionalBody)
+	return err
+}
+
+var (
+	_ = Generator(DefaultGen{})
+)

cmd/libs/go2idl/generator/default_package.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+// DefaultPackage contains a default implentation of Package.
+type DefaultPackage struct {
+	// Short name of package, used in the "package xxxx" line.
+	PackageName string
+	// Import path of the package, and the location on disk of the package.
+	PackagePath string
+
+	// Emitted at the top of every file.
+	HeaderText []byte
+
+	// Emitted only for a "doc.go" file; appended to the HeaderText for
+	// that file.
+	PackageDocumentation []byte
+
+	// If non-nil, will be called on "Generators"; otherwise, the static
+	// list will be used. So you should set only one of these two fields.
+	GeneratorFunc func(*Context) []Generator
+	GeneratorList []Generator
+
+	// Optional; filters the types exposed to the generators.
+	FilterFunc func(*Context, *types.Type) bool
+}
+
+func (d *DefaultPackage) Name() string { return d.PackageName }
+func (d *DefaultPackage) Path() string { return d.PackagePath }
+
+func (d *DefaultPackage) Filter(c *Context, t *types.Type) bool {
+	if d.FilterFunc != nil {
+		return d.FilterFunc(c, t)
+	}
+	return true
+}
+
+func (d *DefaultPackage) Generators(c *Context) []Generator {
+	if d.GeneratorFunc != nil {
+		return d.GeneratorFunc(c)
+	}
+	return d.GeneratorList
+}
+
+func (d *DefaultPackage) Header(filename string) []byte {
+	if filename == "doc.go" {
+		return append(d.HeaderText, d.PackageDocumentation...)
+	}
+	return d.HeaderText
+}
+
+var (
+	_ = Package(&DefaultPackage{})
+)

cmd/libs/go2idl/generator/doc.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator defines an interface for code generators to implement.
+//
+// To use this package, you'll implement the "Package" and "Generator"
+// interfaces; you'll call NewContext to load up the types you want to work
+// with, and then you'll call one or more of the Execute methods. See the
+// interface definitions for explanations. All output will have gofmt called on
+// it automatically, so you do not need to worry about generating correct
+// indentation.
+//
+// This package also exposes SnippetWriter. SnippetWriter reduces to a minimum
+// the boilerplate involved in setting up a template from go's text/template
+// package. Additionally, all naming systems in the Context will be added as
+// functions to the parsed template, so that they can be called directly from
+// your templates!
+package generator

cmd/libs/go2idl/generator/error_tracker.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"io"
+)
+
+// ErrorTracker tracks errors to the underlying writer, so that you can ignore
+// them until you're ready to return.
+type ErrorTracker struct {
+	io.Writer
+	err error
+}
+
+// NewErrorTracker makes a new error tracker; note that it implements io.Writer.
+func NewErrorTracker(w io.Writer) *ErrorTracker {
+	return &ErrorTracker{Writer: w}
+}
+
+// Write intercepts calls to Write.
+func (et *ErrorTracker) Write(p []byte) (n int, err error) {
+	if et.err != nil {
+		return 0, et.err
+	}
+	n, err = et.Writer.Write(p)
+	if err != nil {
+		et.err = err
+	}
+	return n, err
+}
+
+// Error returns nil if no error has occurred, otherwise it returns the error.
+func (et *ErrorTracker) Error() error {
+	return et.err
+}

cmd/libs/go2idl/generator/execute.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"bytes"
+	"fmt"
+	"go/format"
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/namer"
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+// ExecutePackages runs the generators for every package in 'packages'. 'outDir'
+// is the base directory in which to place all the generated packages; it
+// should be a physical path on disk, not an import path. e.g.:
+// /path/to/home/path/to/gopath/src/
+// Each package has its import path already, this will be appended to 'outDir'.
+func (c *Context) ExecutePackages(outDir string, packages Packages) error {
+	for _, p := range packages {
+		if err := c.ExecutePackage(outDir, p); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+type file struct {
+	name        string
+	packageName string
+	header      []byte
+	imports     map[string]struct{}
+	vars        bytes.Buffer
+	consts      bytes.Buffer
+	body        bytes.Buffer
+}
+
+func (f *file) assembleToFile(pathname string) error {
+	log.Printf("Assembling file %q", pathname)
+	destFile, err := os.Create(pathname)
+	if err != nil {
+		return err
+	}
+	defer destFile.Close()
+
+	b := &bytes.Buffer{}
+	et := NewErrorTracker(b)
+	f.assemble(et)
+	if et.Error() != nil {
+		return et.Error()
+	}
+	if formatted, err := format.Source(b.Bytes()); err != nil {
+		log.Printf("Warning: unable to run gofmt on %q (%v).", pathname, err)
+		_, err = destFile.Write(b.Bytes())
+		return err
+	} else {
+		_, err = destFile.Write(formatted)
+		return err
+	}
+}
+
+func (f *file) assemble(w io.Writer) {
+	w.Write(f.header)
+	fmt.Fprintf(w, "package %v\n\n", f.packageName)
+
+	if len(f.imports) > 0 {
+		fmt.Fprint(w, "import (\n")
+		for i := range f.imports {
+			if strings.Contains(i, "\"") {
+				// they included quotes, or are using the
+				// `name "path/to/pkg"` format.
+				fmt.Fprintf(w, "\t%s\n", i)
+			} else {
+				fmt.Fprintf(w, "\t%q\n", i)
+			}
+		}
+		fmt.Fprint(w, ")\n\n")
+	}
+
+	if f.vars.Len() > 0 {
+		fmt.Fprint(w, "var (\n")
+		w.Write(f.vars.Bytes())
+		fmt.Fprint(w, ")\n\n")
+	}
+
+	if f.consts.Len() > 0 {
+		fmt.Fprint(w, "const (\n")
+		w.Write(f.consts.Bytes())
+		fmt.Fprint(w, ")\n\n")
+	}
+
+	w.Write(f.body.Bytes())
+}
+
+// format should be one line only, and not end with \n.
+func addIndentHeaderComment(b *bytes.Buffer, format string, args ...interface{}) {
+	if b.Len() > 0 {
+		fmt.Fprintf(b, "\n\t// "+format+"\n", args...)
+	} else {
+		fmt.Fprintf(b, "\t// "+format+"\n", args...)
+	}
+}
+
+func (c *Context) filteredBy(f func(*Context, *types.Type) bool) *Context {
+	c2 := *c
+	c2.Order = []*types.Type{}
+	for _, t := range c.Order {
+		if f(c, t) {
+			c2.Order = append(c2.Order, t)
+		}
+	}
+	return &c2
+}
+
+// make a new context; inheret c.Namers, but add on 'namers'. In case of a name
+// collision, the namer in 'namers' wins.
+func (c *Context) addNameSystems(namers namer.NameSystems) *Context {
+	if namers == nil {
+		return c
+	}
+	c2 := *c
+	// Copy the existing name systems so we don't corrupt a parent context
+	c2.Namers = namer.NameSystems{}
+	for k, v := range c.Namers {
+		c2.Namers[k] = v
+	}
+
+	for name, namer := range namers {
+		c2.Namers[name] = namer
+	}
+	return &c2
+}
+
+// ExecutePackage executes a single package. 'outDir' is the base directory in
+// which to place the package; it should be a physical path on disk, not an
+// import path. e.g.: '/path/to/home/path/to/gopath/src/' The package knows its
+// import path already, this will be appended to 'outDir'.
+func (c *Context) ExecutePackage(outDir string, p Package) error {
+	path := filepath.Join(outDir, p.Path())
+	log.Printf("Executing package %v into %v", p.Name(), path)
+	// Filter out any types the *package* doesn't care about.
+	packageContext := c.filteredBy(p.Filter)
+	os.MkdirAll(path, 0755)
+	files := map[string]*file{}
+	for _, g := range p.Generators(packageContext) {
+		// Filter out types the *generator* doesn't care about.
+		genContext := packageContext.filteredBy(g.Filter)
+		// Now add any extra name systems defined by this generator
+		genContext = genContext.addNameSystems(g.Namers(genContext))
+
+		f := files[g.Filename()]
+		if f == nil {
+			// This is the first generator to reference this file, so start it.
+			f = &file{
+				name:        g.Filename(),
+				packageName: p.Name(),
+				header:      p.Header(g.Filename()),
+				imports:     map[string]struct{}{},
+			}
+			files[f.name] = f
+		}
+		if vars := g.PackageVars(genContext); len(vars) > 0 {
+			addIndentHeaderComment(&f.vars, "Package-wide variables from generator %q.", g.Name())
+			for _, v := range vars {
+				if _, err := fmt.Fprintf(&f.vars, "\t%s\n", v); err != nil {
+					return err
+				}
+			}
+		}
+		if consts := g.PackageVars(genContext); len(consts) > 0 {
+			addIndentHeaderComment(&f.consts, "Package-wide consts from generator %q.", g.Name())
+			for _, v := range consts {
+				if _, err := fmt.Fprintf(&f.consts, "\t%s\n", v); err != nil {
+					return err
+				}
+			}
+		}
+		if err := genContext.executeBody(&f.body, g); err != nil {
+			return err
+		}
+		if imports := g.Imports(genContext); len(imports) > 0 {
+			for _, i := range imports {
+				f.imports[i] = struct{}{}
+			}
+		}
+	}
+
+	for _, f := range files {
+		if err := f.assembleToFile(filepath.Join(path, f.name)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (c *Context) executeBody(w io.Writer, generator Generator) error {
+	et := NewErrorTracker(w)
+	if err := generator.Init(c, et); err != nil {
+		return err
+	}
+	for _, t := range c.Order {
+		if err := generator.GenerateType(c, t, et); err != nil {
+			return err
+		}
+	}
+	return et.Error()
+}

cmd/libs/go2idl/generator/generator.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"io"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/namer"
+	"k8s.io/kubernetes/cmd/libs/go2idl/parser"
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+// Package contains the contract for generating a package.
+type Package interface {
+	// Name returns the package short name.
+	Name() string
+	// Path returns the package import path.
+	Path() string
+
+	// Filter should return true if this package cares about this type.
+	// Otherwise, this type will be ommitted from the type ordering for
+	// this package.
+	Filter(*Context, *types.Type) bool
+
+	// Header should return a header for the file, including comment markers.
+	// Useful for copyright notices and doc strings. Include an
+	// autogeneration notice! Do not include the "package x" line.
+	Header(filename string) []byte
+
+	// Generators returns the list of generators for this package. It is
+	// allowed for more than one generator to write to the same file.
+	// A Context is passed in case the list of generators depends on the
+	// input types.
+	Generators(*Context) []Generator
+}
+
+// Packages is a list of packages to generate.
+type Packages []Package
+
+// Generator is the contract for anything that wants to do auto-generation.
+// It's expected that the io.Writers passed to the below functions will be
+// ErrorTrackers; this allows implementations to not check for io errors,
+// making more readable code.
+//
+// The call order for the functions that take a Context is:
+// 1. Filter()        // Subsequent calls see only types that pass this.
+// 2. Namers()        // Subsequent calls see the namers provided by this.
+// 3. PackageVars()
+// 4. PackageConsts()
+// 5. Init()
+// 6. GenerateType()  // Called N times, once per type in the context's Order.
+// 7. Imports()
+//
+// You may have multiple generators for the same file.
+type Generator interface {
+	// The name of this generator. Will be included in generated comments.
+	Name() string
+
+	// Filter should return true if this generator cares about this type.
+	// (otherwise, GenerateType will not be called.)
+	//
+	// Filter is called before any of the generator's other functions;
+	// subsequent calls will get a context with only the types that passed
+	// this filter.
+	Filter(*Context, *types.Type) bool
+
+	// If this generator needs special namers, return them here. These will
+	// override the original namers in the context if there is a collision.
+	// You may return nil if you don't need special names. These names will
+	// be available in the context passed to the rest of the generator's
+	// functions.
+	//
+	// A use case for this is to return a namer that tracks imports.
+	Namers(*Context) namer.NameSystems
+
+	// Init should write an init function, and any other content that's not
+	// generated per-type. (It's not intended for generator specific
+	// initialization! Do that when your Package constructs the
+	// Generators.)
+	Init(*Context, io.Writer) error
+
+	// PackageVars should emit an array of variable lines. They will be
+	// placed in a var ( ... ) block. There's no need to include a leading
+	// \t or trailing \n.
+	PackageVars(*Context) []string
+
+	// PackageConsts should emit an array of constant lines. They will be
+	// placed in a const ( ... ) block. There's no need to include a leading
+	// \t or trailing \n.
+	PackageConsts(*Context) []string
+
+	// GenerateType should emit the code for a particular type.
+	GenerateType(*Context, *types.Type, io.Writer) error
+
+	// Imports should return a list of necessary imports. They will be
+	// formatted correctly. You do not need to include quotation marks,
+	// return only the package name; alternatively, you can also return
+	// imports in the format `name "path/to/pkg"`. Imports will be called
+	// after Init, PackageVars, PackageConsts, and GenerateType, to allow
+	// you to keep track of what imports you actually need.
+	Imports(*Context) []string
+
+	// Preferred file name of this generator, not including a path. It is
+	// allowed for multiple generators to use the same filename, but it's
+	// up to you to make sure they don't have colliding import names.
+	// TODO: provide per-file import tracking, removing the requirement
+	// that generators coordinate..
+	Filename() string
+}
+
+// Context is global context for individual generators to consume.
+type Context struct {
+	// A map from the naming system to the names for that system. E.g., you
+	// might have public names and several private naming systems.
+	Namers namer.NameSystems
+
+	// All the types, in case you want to look up something.
+	Universe types.Universe
+
+	// The canonical ordering of the types (will be filtered by both the
+	// Package's and Generator's Filter methods).
+	Order []*types.Type
+}
+
+// NewContext generates a context from the given builder, naming systems, and
+// the naming system you wish to construct the canonical ordering from.
+func NewContext(b *parser.Builder, nameSystems namer.NameSystems, canonicalOrderName string) (*Context, error) {
+	u, err := b.FindTypes()
+	if err != nil {
+		return nil, err
+	}
+
+	c := &Context{
+		Namers:   namer.NameSystems{},
+		Universe: u,
+	}
+
+	for name, systemNamer := range nameSystems {
+		c.Namers[name] = systemNamer
+		if name == canonicalOrderName {
+			orderer := namer.Orderer{systemNamer}
+			c.Order = orderer.Order(u)
+		}
+	}
+	return c, nil
+}

cmd/libs/go2idl/generator/import_tracker.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"path/filepath"
+	"strings"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+// ImportTracker may be passed to a namer.RawNamer, to track the imports needed
+// for the types it names.
+//
+// TODO: pay attention to the package name (instead of renaming every package).
+// TODO: Figure out the best way to make names for packages that collide.
+type ImportTracker struct {
+	pathToName map[string]string
+	// forbidden names are in here. (e.g. "go" is a directory in which
+	// there is code, but "go" is not a legal name for a package, so we put
+	// it here to prevent us from naming any package "go")
+	nameToPath map[string]string
+}
+
+func NewImportTracker(types ...*types.Type) *ImportTracker {
+	tracker := &ImportTracker{
+		pathToName: map[string]string{},
+		nameToPath: map[string]string{
+			"go": "",
+			// Add other forbidden keywords that also happen to be
+			// package names here.
+		},
+	}
+	tracker.AddTypes(types...)
+	return tracker
+}
+
+func (tracker *ImportTracker) AddTypes(types ...*types.Type) {
+	for _, t := range types {
+		tracker.AddType(t)
+	}
+}
+func (tracker *ImportTracker) AddType(t *types.Type) {
+	path := t.Name.Package
+	if path == "" {
+		return
+	}
+	if _, ok := tracker.pathToName[path]; ok {
+		return
+	}
+	dirs := strings.Split(path, string(filepath.Separator))
+	for n := len(dirs) - 1; n >= 0; n-- {
+		// TODO: bikeshed about whether it's more readable to have an
+		// _, something else, or nothing between directory names.
+		name := strings.Join(dirs[n:], "_")
+		// These characters commonly appear in import paths for go
+		// packages, but aren't legal go names. So we'll sanitize.
+		name = strings.Replace(name, ".", "_", -1)
+		name = strings.Replace(name, "-", "_", -1)
+		if _, found := tracker.nameToPath[name]; found {
+			// This name collides with some other package
+			continue
+		}
+		tracker.nameToPath[name] = path
+		tracker.pathToName[path] = name
+		return
+	}
+	panic("can't find import for " + path)
+}
+
+func (tracker *ImportTracker) ImportLines() []string {
+	out := []string{}
+	for path, name := range tracker.pathToName {
+		out = append(out, name+" \""+path+"\"")
+	}
+	return out
+}
+
+// LocalNameOf returns the name you would use to refer to the package at the
+// specified path within the body of a file.
+func (tracker *ImportTracker) LocalNameOf(path string) string {
+	return tracker.pathToName[path]
+}

cmd/libs/go2idl/generator/snippet_writer.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator
+
+import (
+	"fmt"
+	"io"
+	"runtime"
+	"text/template"
+)
+
+// SnippetWriter is an attempt to make the template library usable.
+// Methods are chainable, and you don't have to check Error() until you're all
+// done.
+type SnippetWriter struct {
+	w       io.Writer
+	context *Context
+	// Left & right delimiters. text/template defaults to "{{" and "}}"
+	// which is totally unusable for go code based templates.
+	left, right string
+	funcMap     template.FuncMap
+	err         error
+}
+
+// w is the destination; left and right are the delimiters; @ and $ are both
+// reasonable choices.
+//
+// c is used to make a function for every naming system, to which you can pass
+// a type and get the corresponding name.
+func NewSnippetWriter(w io.Writer, c *Context, left, right string) *SnippetWriter {
+	sw := &SnippetWriter{
+		w:       w,
+		context: c,
+		left:    left,
+		right:   right,
+		funcMap: template.FuncMap{},
+	}
+	for name, namer := range c.Namers {
+		sw.funcMap[name] = namer.Name
+	}
+	return sw
+}
+
+// Do parses format and runs args through it. You can have arbitrary logic in
+// the format (see the text/template documentation), but consider running many
+// short templaces, with ordinary go logic in between--this may be more
+// readable. Do is chainable. Any error causes every other call to do to be
+// ignored, and the error will be returned by Error(). So you can check it just
+// once, at the end of your function.
+//
+// 'args' can be quite literally anything; read the text/template documentation
+// for details. Maps and structs work particularly nicely. Conveniently, the
+// types package is designed to have structs that are easily referencable from
+// the template language.
+//
+// Example:
+//
+// sw := generator.NewSnippetWriter(outBuffer, context, "$", "$")
+// sw.Do(`The public type name is: $.type|public$`, map[string]interface{}{"type": t})
+// return sw.Error()
+//
+// Where:
+// * "$" starts a template directive
+// * "." references the entire thing passed as args
+// * "type" therefore sees a map and looks up the key "type"
+// * "|" means "pass the thing on the left to the thing on the right"
+// * "public" is the name of a naming system, so the SnippetWriter has given
+//   the template a function called "public" that takes a *types.Type and
+//   returns the naming system's name. E.g., if the type is "string" this might
+//   return "String".
+// * the second "$" ends the template directive.
+//
+// The map is actually not necessary. The below does the same thing:
+//
+// sw.Do(`The public type name is: $.|public$`, t)
+//
+// You may or may not find it more readable to use the map with a descriptive
+// key, but if you want to pass more than one arg, the map or a custom struct
+// becomes a requirement. You can do arbitrary logic inside these templates,
+// but you should consider doing the logic in go and stitching them together
+// for the sake of your readers.
+func (s *SnippetWriter) Do(format string, args interface{}) *SnippetWriter {
+	if s.err != nil {
+		return s
+	}
+	// Name the template by source file:line so it can be found when
+	// there's an error.
+	_, file, line, _ := runtime.Caller(1)
+	tmpl, err := template.
+		New(fmt.Sprintf("%s:%d", file, line)).
+		Delims(s.left, s.right).
+		Funcs(s.funcMap).
+		Parse(format)
+	if err != nil {
+		s.err = err
+		return s
+	}
+	err = tmpl.Execute(s.w, args)
+	if err != nil {
+		s.err = err
+	}
+	return s
+}
+
+// Error returns any encountered error.
+func (s *SnippetWriter) Error() error {
+	return s.err
+}

cmd/libs/go2idl/generator/snippet_writer_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 generator_test
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/generator"
+	"k8s.io/kubernetes/cmd/libs/go2idl/namer"
+	"k8s.io/kubernetes/cmd/libs/go2idl/parser"
+)
+
+func construct(t *testing.T, files map[string]string) *generator.Context {
+	b := parser.New()
+	for name, src := range files {
+		if err := b.AddFile(name, []byte(src)); err != nil {
+			t.Fatal(err)
+		}
+	}
+	c, err := generator.NewContext(b, namer.NameSystems{
+		"public":  namer.NewPublicNamer(0),
+		"private": namer.NewPrivateNamer(0),
+	}, "public")
+	if err != nil {
+		t.Fatal(err)
+	}
+	return c
+}
+
+func TestSnippetWriter(t *testing.T) {
+	var structTest = map[string]string{
+		"base/foo/proto/foo.go": `
+package foo
+
+// Blah is a test.
+// A test, I tell you.
+type Blah struct {
+	// A is the first field.
+	A int64 ` + "`" + `json:"a"` + "`" + `
+
+	// B is the second field.
+	// Multiline comments work.
+	B string ` + "`" + `json:"b"` + "`" + `
+}
+`,
+	}
+
+	c := construct(t, structTest)
+	b := &bytes.Buffer{}
+	err := generator.NewSnippetWriter(b, c, "$", "$").
+		Do("$.|public$$.|private$", c.Order[0]).
+		Error()
+	if err != nil {
+		t.Errorf("Unexpected error %v", err)
+	}
+	if e, a := "Blahblah", b.String(); e != a {
+		t.Errorf("Expected %q, got %q", e, a)
+	}
+
+	err = generator.NewSnippetWriter(b, c, "$", "$").
+		Do("$.|public", c.Order[0]).
+		Error()
+	if err == nil {
+		t.Errorf("expected error on invalid template")
+	} else {
+		// Dear reader, I apologize for making the worst change
+		// detection test in the history of ever.
+		if e, a := "snippet_writer_test.go:78", err.Error(); !strings.Contains(a, e) {
+			t.Errorf("Expected %q but didn't find it in %q", e, a)
+		}
+	}
+}

cmd/libs/go2idl/namer/doc.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 namer has support for making different type naming systems.
+//
+// This is because sometimes you want to refer to the literal type, sometimes
+// you want to make a name for the thing you're generating, and you want to
+// make the name based on the type. For example, if you have `type foo string`,
+// you want to be able to generate something like `func FooPrinter(f *foo) {
+// Print(string(*f)) }`; that is, you want to refer to a public name, a literal
+// name, and the underlying literal name.
+//
+// This package supports the idea of a "Namer" and a set of "NameSystems" to
+// support these use cases.
+//
+// Additionally, a "RawNamer" can optionally keep track of what needs to be
+// imported.
+package namer

cmd/libs/go2idl/namer/namer_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 namer
+
+import (
+	"reflect"
+	"testing"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+func TestNameStrategy(t *testing.T) {
+	u := types.Universe{}
+
+	// Add some types.
+	base := u.Get(types.Name{"foo/bar", "Baz"})
+	base.Kind = types.Struct
+
+	tmp := u.Get(types.Name{"", "[]bar.Baz"})
+	tmp.Kind = types.Slice
+	tmp.Elem = base
+
+	tmp = u.Get(types.Name{"", "map[string]bar.Baz"})
+	tmp.Kind = types.Map
+	tmp.Key = types.String
+	tmp.Elem = base
+
+	tmp = u.Get(types.Name{"foo/other", "Baz"})
+	tmp.Kind = types.Struct
+	tmp.Members = []types.Member{{
+		Embedded: true,
+		Type:     base,
+	}}
+
+	u.Get(types.Name{"", "string"})
+
+	o := Orderer{NewPublicNamer(0)}
+	order := o.Order(u)
+	orderedNames := make([]string, len(order))
+	for i, t := range order {
+		orderedNames[i] = o.Name(t)
+	}
+	expect := []string{"Baz", "Baz", "MapStringToBaz", "SliceBaz", "String"}
+	if e, a := expect, orderedNames; !reflect.DeepEqual(e, a) {
+		t.Errorf("Wanted %#v, got %#v", e, a)
+	}
+
+	o = Orderer{NewRawNamer(nil)}
+	order = o.Order(u)
+	orderedNames = make([]string, len(order))
+	for i, t := range order {
+		orderedNames[i] = o.Name(t)
+	}
+
+	expect = []string{"[]bar.Baz", "bar.Baz", "map[string]bar.Baz", "other.Baz", "string"}
+	if e, a := expect, orderedNames; !reflect.DeepEqual(e, a) {
+		t.Errorf("Wanted %#v, got %#v", e, a)
+	}
+
+	o = Orderer{NewPublicNamer(1)}
+	order = o.Order(u)
+	orderedNames = make([]string, len(order))
+	for i, t := range order {
+		orderedNames[i] = o.Name(t)
+	}
+	expect = []string{"BarBaz", "MapStringToBarBaz", "OtherBaz", "SliceBarBaz", "String"}
+	if e, a := expect, orderedNames; !reflect.DeepEqual(e, a) {
+		t.Errorf("Wanted %#v, got %#v", e, a)
+	}
+}

cmd/libs/go2idl/namer/order.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 namer
+
+import (
+	"sort"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+// Orderer produces an ordering of types given a Namer.
+type Orderer struct {
+	Namer
+}
+
+// Order assigns a name to every type, and returns a list sorted by those
+// names.
+func (o *Orderer) Order(u types.Universe) []*types.Type {
+	list := tList{
+		namer: o.Namer,
+	}
+	for _, p := range u {
+		for _, t := range p.Types {
+			list.types = append(list.types, t)
+		}
+	}
+	sort.Sort(list)
+	return list.types
+}
+
+type tList struct {
+	namer Namer
+	types []*types.Type
+}
+
+func (t tList) Len() int           { return len(t.types) }
+func (t tList) Less(i, j int) bool { return t.namer.Name(t.types[i]) < t.namer.Name(t.types[j]) }
+func (t tList) Swap(i, j int)      { t.types[i], t.types[j] = t.types[j], t.types[i] }

cmd/libs/go2idl/parser/doc.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 parser provides code to parse go files, type-check them, extract the
+// types.
+package parser

cmd/libs/go2idl/parser/parse_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 parser_test
+
+import (
+	"bytes"
+	"reflect"
+	"testing"
+	"text/template"
+
+	"k8s.io/kubernetes/cmd/libs/go2idl/namer"
+	"k8s.io/kubernetes/cmd/libs/go2idl/parser"
+	"k8s.io/kubernetes/cmd/libs/go2idl/types"
+)
+
+func construct(t *testing.T, files map[string]string, testNamer namer.Namer) (*parser.Builder, types.Universe, []*types.Type) {
+	b := parser.New()
+	for name, src := range files {
+		if err := b.AddFile(name, []byte(src)); err != nil {
+			t.Fatal(err)
+		}
+	}
+	u, err := b.FindTypes()
+	if err != nil {
+		t.Fatal(err)
+	}
+	orderer := namer.Orderer{testNamer}
+	o := orderer.Order(u)
+	return b, u, o
+}
+
+func TestBuilder(t *testing.T) {
+	var testFiles = map[string]string{
+		"base/foo/proto/foo.go": `
+package foo
+
+import (
+	"base/common/proto"
+)
+
+type Blah struct {
+	common.Object
+	Count int64
+	Frobbers map[string]*Frobber
+	Baz []Object
+	Nickname *string
+	NumberIsAFavorite map[int]bool
+}
+
+type Frobber struct {
+	Name string
+	Amount int64
+}
+
+type Object struct {
+	common.Object
+}
+
+`,
+		"base/common/proto/common.go": `
+package common
+
+type Object struct {
+	ID int64
+}
+`,
+	}
+
+	var tmplText = `
+package o
+{{define "Struct"}}type {{Name .}} interface { {{range $m := .Members}}{{$n := Name $m.Type}}
+	{{if $m.Embedded}}{{$n}}{{else}}{{$m.Name}}() {{$n}}{{if $m.Type.Elem}}{{else}}
+	Set{{$m.Name}}({{$n}}){{end}}{{end}}{{end}}
+}
+
+{{end}}
+{{range $t := .}}{{if eq $t.Kind "Struct"}}{{template "Struct" $t}}{{end}}{{end}}`
+
+	var expect = `
+package o
+
+type CommonObject interface { 
+	ID() Int64
+	SetID(Int64)
+}
+
+type FooBlah interface { 
+	CommonObject
+	Count() Int64
+	SetCount(Int64)
+	Frobbers() MapStringToPointerFooFrobber
+	Baz() SliceFooObject
+	Nickname() PointerString
+	NumberIsAFavorite() MapIntToBool
+}
+
+type FooFrobber interface { 
+	Name() String
+	SetName(String)
+	Amount() Int64
+	SetAmount(Int64)
+}
+
+type FooObject interface { 
+	CommonObject
+}
+
+`
+	testNamer := namer.NewPublicNamer(1, "proto")
+	_, u, o := construct(t, testFiles, testNamer)
+	t.Logf("\n%v\n\n", o)
+	tmpl := template.Must(
+		template.New("").
+			Funcs(
+			map[string]interface{}{
+				"Name": testNamer.Name,
+			}).
+			Parse(tmplText),
+	)
+	buf := &bytes.Buffer{}
+	tmpl.Execute(buf, o)
+	if e, a := expect, buf.String(); e != a {
+		t.Errorf("Wanted, got:\n%v\n-----\n%v\n", e, a)
+	}
+
+	if p := u.Package("base/foo/proto"); !p.HasImport("base/common/proto") {
+		t.Errorf("Unexpected lack of import line: %#s", p.Imports)
+	}
+}
+
+func TestStructParse(t *testing.T) {
+	var structTest = map[string]string{
+		"base/foo/proto/foo.go": `
+package foo
+
+// Blah is a test.
+// A test, I tell you.
+type Blah struct {
+	// A is the first field.
+	A int64 ` + "`" + `json:"a"` + "`" + `
+
+	// B is the second field.
+	// Multiline comments work.
+	B string ` + "`" + `json:"b"` + "`" + `
+}
+`,
+	}
+
+	_, u, o := construct(t, structTest, namer.NewPublicNamer(0))
+	t.Logf("%#v", o)
+	blahT := u.Get(types.Name{"base/foo/proto", "Blah"})
+	if blahT == nil {
+		t.Fatal("type not found")
+	}
+	if e, a := types.Struct, blahT.Kind; e != a {
+		t.Errorf("struct kind wrong, wanted %v, got %v", e, a)
+	}
+	if e, a := "Blah is a test.\nA test, I tell you.\n", blahT.CommentLines; e != a {
+		t.Errorf("struct comment wrong, wanted %v, got %v", e, a)
+	}
+	m := types.Member{
+		Name:         "B",
+		Embedded:     false,
+		CommentLines: "B is the second field.\nMultiline comments work.\n",
+		Tags:         `json:"b"`,
+		Type:         types.String,
+	}
+	if e, a := m, blahT.Members[1]; !reflect.DeepEqual(e, a) {
+		t.Errorf("wanted, got:\n%#v\n%#v", e, a)
+	}
+}
+
+func TestTypeKindParse(t *testing.T) {
+	var testFiles = map[string]string{
+		"a/foo.go": "package a\ntype Test string\n",
+		"b/foo.go": "package b\ntype Test map[int]string\n",
+		"c/foo.go": "package c\ntype Test []string\n",
+		"d/foo.go": "package d\ntype Test struct{a int; b struct{a int}; c map[int]string; d *string}\n",
+		"e/foo.go": "package e\ntype Test *string\n",
+		"f/foo.go": `
+package f
+import (
+	"a"
+	"b"
+)
+type Test []a.Test
+type Test2 *a.Test
+type Test3 map[a.Test]b.Test
+type Test4 struct {
+	a struct {a a.Test; b b.Test}
+	b map[a.Test]b.Test
+	c *a.Test
+	d []a.Test
+	e []string
+}
+`,
+		"g/foo.go": `
+package g
+type Test func(a, b string) (c, d string)
+func (t Test) Method(a, b string) (c, d string) { return t(a, b) }
+type Interface interface{Method(a, b string) (c, d string)}
+`,
+	}
+
+	// Check that the right types are found, and the namers give the expected names.
+
+	assertions := []struct {
+		Package, Name string
+		k             types.Kind
+		names         []string
+	}{
+		{
+			Package: "a", Name: "Test", k: types.Alias,
+			names: []string{"Test", "ATest", "test", "aTest", "a.Test"},
+		},
+		{
+			Package: "b", Name: "Test", k: types.Map,
+			names: []string{"Test", "BTest", "test", "bTest", "b.Test"},
+		},
+		{
+			Package: "c", Name: "Test", k: types.Slice,
+			names: []string{"Test", "CTest", "test", "cTest", "c.Test"},
+		},
+		{
+			Package: "d", Name: "Test", k: types.Struct,
+			names: []string{"Test", "DTest", "test", "dTest", "d.Test"},
+		},
+		{
+			Package: "e", Name: "Test", k: types.Pointer,
+			names: []string{"Test", "ETest", "test", "eTest", "e.Test"},
+		},
+		{
+			Package: "f", Name: "Test", k: types.Slice,
+			names: []string{"Test", "FTest", "test", "fTest", "f.Test"},
+		},
+		{
+			Package: "g", Name: "Test", k: types.Func,
+			names: []string{"Test", "GTest", "test", "gTest", "g.Test"},
+		},
+		{
+			Package: "g", Name: "Interface", k: types.Interface,
+			names: []string{"Interface", "GInterface", "interface", "gInterface", "g.Interface"},
+		},
+		{
+			Package: "", Name: "string", k: types.Builtin,
+			names: []string{"String", "String", "string", "string", "string"},
+		},
+		{
+			Package: "", Name: "int", k: types.Builtin,
+			names: []string{"Int", "Int", "int", "int", "int"},
+		},
+		{
+			Package: "", Name: "struct{a int}", k: types.Struct,
+			names: []string{"StructInt", "StructInt", "structInt", "structInt", "struct{a int}"},
+		},
+		{
+			Package: "", Name: "struct{a a.Test; b b.Test}", k: types.Struct,
+			names: []string{"StructTestTest", "StructATestBTest", "structTestTest", "structATestBTest", "struct{a a.Test; b b.Test}"},
+		},
+		{
+			Package: "", Name: "map[int]string", k: types.Map,
+			names: []string{"MapIntToString", "MapIntToString", "mapIntToString", "mapIntToString", "map[int]string"},
+		},
+		{
+			Package: "", Name: "map[a.Test]b.Test", k: types.Map,
+			names: []string{"MapTestToTest", "MapATestToBTest", "mapTestToTest", "mapATestToBTest", "map[a.Test]b.Test"},
+		},
+		{
+			Package: "", Name: "[]string", k: types.Slice,
+			names: []string{"SliceString", "SliceString", "sliceString", "sliceString", "[]string"},
+		},
+		{
+			Package: "", Name: "[]a.Test", k: types.Slice,
+			names: []string{"SliceTest", "SliceATest", "sliceTest", "sliceATest", "[]a.Test"},
+		},
+		{
+			Package: "", Name: "*string", k: types.Pointer,
+			names: []string{"PointerString", "PointerString", "pointerString", "pointerString", "*string"},
+		},
+		{
+			Package: "", Name: "*a.Test", k: types.Pointer,
+			names: []string{"PointerTest", "PointerATest", "pointerTest", "pointerATest", "*a.Test"},
+		},
+	}
+
+	namers := []namer.Namer{
+		namer.NewPublicNamer(0),
+		namer.NewPublicNamer(1),
+		namer.NewPrivateNamer(0),
+		namer.NewPrivateNamer(1),
+		namer.NewRawNamer(nil),
+	}
+
+	for nameIndex, namer := range namers {
+		_, u, _ := construct(t, testFiles, namer)
+		t.Logf("Found types:\n")
+		for pkgName, pkg := range u {
+			for typeName, cur := range pkg.Types {
+				t.Logf("%q-%q: %s %s", pkgName, typeName, cur.Name, cur.Kind)
+			}
+		}
+		t.Logf("\n\n")
+
+		for _, item := range assertions {
+			n := types.Name{Package: item.Package, Name: item.Name}
+			thisType := u.Get(n)
+			if thisType == nil {
+				t.Errorf("type %s not found", n)
+				continue
+			}
+			if e, a := item.k, thisType.Kind; e != a {
+				t.Errorf("%v-%s: type kind wrong, wanted %v, got %v (%#v)", nameIndex, n, e, a, thisType)
+			}
+			if e, a := item.names[nameIndex], namer.Name(thisType); e != a {
+				t.Errorf("%v-%s: Expected %q, got %q", nameIndex, n, e, a)
+			}
+		}
+
+		// Also do some one-off checks
+		gtest := u.Get(types.Name{"g", "Test"})
+		if e, a := 1, len(gtest.Methods); e != a {
+			t.Errorf("expected %v but found %v methods: %#v", e, a, gtest)
+		}
+		iface := u.Get(types.Name{"g", "Interface"})
+		if e, a := 1, len(iface.Methods); e != a {
+			t.Errorf("expected %v but found %v methods: %#v", e, a, iface)
+		}
+	}
+}

cmd/libs/go2idl/types/comments.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types contains go type information, packaged in a way that makes
+// auto-generation convenient, whether by template or straight go functions.
+package types
+
+import (
+	"strings"
+)
+
+// ExtractCommentTags parses comments for lines of the form:
+//
+//   'marker'+"key1=value1,key2=value2".
+//
+// Values are optional; 'true' is the default. If a key is set multiple times,
+// the last one wins.
+//
+// Example: if you pass "+" for 'marker', and the following two lines are in
+// the comments:
+//   +foo=value1,bar
+//   +foo=value2,baz="frobber"
+// Then this function will return:
+//   map[string]string{"foo":"value2", "bar": "true", "baz": "frobber"}
+//
+// TODO: Basically we need to define a standard way of giving instructions to
+// autogenerators in the comments of a type. This is a first iteration of that.
+// TODO: allow multiple values per key?
+func ExtractCommentTags(marker, allLines string) map[string]string {
+	lines := strings.Split(allLines, "\n")
+	out := map[string]string{}
+	for _, line := range lines {
+		line = strings.Trim(line, " ")
+		if len(line) == 0 {
+			continue
+		}
+		if !strings.HasPrefix(line, marker) {
+			continue
+		}
+		pairs := strings.Split(line[len(marker):], ",")
+		for _, p := range pairs {
+			kv := strings.Split(p, "=")
+			if len(kv) == 2 {
+				out[kv[0]] = kv[1]
+			} else if len(kv) == 1 {
+				out[kv[0]] = "true"
+			}
+		}
+	}
+	return out
+}

cmd/libs/go2idl/types/comments_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestExtractCommentTags(t *testing.T) {
+	commentLines := `
+Human comment that is ignored.
++foo=value1,bar
++foo=value2,baz=frobber
+`
+	a := ExtractCommentTags("+", commentLines)
+	e := map[string]string{"foo": "value2", "bar": "true", "baz": "frobber"}
+	if !reflect.DeepEqual(e, a) {
+		t.Errorf("Wanted %#v, got %#v", e, a)
+	}
+}

cmd/libs/go2idl/types/doc.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types contains go type information, packaged in a way that makes
+// auto-generation convenient, whether by template or straight go functions.
+package types

cmd/libs/go2idl/types/flatten.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types
+
+// FlattenMembers recursively takes any embedded members and puts them in the
+// top level, correctly hiding them if the top level hides them. There must not
+// be a cycle-- that implies infinite members.
+//
+// This is useful for e.g. computing all the valid keys in a json struct,
+// properly considering any configuration of embedded structs.
+func FlattenMembers(m []Member) []Member {
+	embedded := []Member{}
+	normal := []Member{}
+	type nameInfo struct {
+		top bool
+		i   int
+	}
+	names := map[string]nameInfo{}
+	for i := range m {
+		if m[i].Embedded && m[i].Type.Kind == Struct {
+			embedded = append(embedded, m[i])
+		} else {
+			normal = append(normal, m[i])
+			names[m[i].Name] = nameInfo{true, len(normal) - 1}
+		}
+	}
+	for i := range embedded {
+		for _, e := range FlattenMembers(embedded[i].Type.Members) {
+			if info, found := names[e.Name]; found {
+				if info.top {
+					continue
+				}
+				if n := normal[info.i]; n.Name == e.Name && n.Type == e.Type {
+					continue
+				}
+				panic("conflicting members")
+			}
+			normal = append(normal, e)
+			names[e.Name] = nameInfo{false, len(normal) - 1}
+		}
+	}
+	return normal
+}

cmd/libs/go2idl/types/flatten_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestFlatten(t *testing.T) {
+	mapType := &Type{
+		Name: Name{"", "map[string]string"},
+		Kind: Map,
+		Key:  String,
+		Elem: String,
+	}
+	m := []Member{
+		{
+			Name:     "Baz",
+			Embedded: true,
+			Type: &Type{
+				Name: Name{"pkg", "Baz"},
+				Kind: Struct,
+				Members: []Member{
+					{Name: "Foo", Type: String},
+					{
+						Name:     "Qux",
+						Embedded: true,
+						Type: &Type{
+							Name:    Name{"pkg", "Qux"},
+							Kind:    Struct,
+							Members: []Member{{Name: "Zot", Type: String}},
+						},
+					},
+				},
+			},
+		},
+		{Name: "Bar", Type: String},
+		{
+			Name:     "NotSureIfLegal",
+			Embedded: true,
+			Type:     mapType,
+		},
+	}
+	e := []Member{
+		{Name: "Bar", Type: String},
+		{Name: "NotSureIfLegal", Type: mapType, Embedded: true},
+		{Name: "Foo", Type: String},
+		{Name: "Zot", Type: String},
+	}
+	if a := FlattenMembers(m); !reflect.DeepEqual(e, a) {
+		t.Errorf("Expected \n%#v\n, got \n%#v\n", e, a)
+	}
+}

cmd/libs/go2idl/types/types.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types
+
+// A type name may have a package qualifier.
+type Name struct {
+	// Empty if embedded or builtin. This is the package path.
+	Package string
+	// The type name.
+	Name string
+}
+
+// String returns the name formatted as a string.
+func (n Name) String() string {
+	if n.Package == "" {
+		return n.Name
+	}
+	return n.Package + "." + n.Name
+}
+
+// The possible classes of types.
+type Kind string
+
+const (
+	// Builtin is a primitive, like bool, string, int.
+	Builtin Kind = "Builtin"
+	Struct  Kind = "Struct"
+	Map     Kind = "Map"
+	Slice   Kind = "Slice"
+	Pointer Kind = "Pointer"
+
+	// Alias is an alias of another type, e.g. in:
+	//   type Foo string
+	//   type Bar Foo
+	// Bar is an alias of Foo.
+	//
+	// In the real go type system, Foo is a "Named" string; but to simplify
+	// generation, this type system will just say that Foo *is* a builtin.
+	// We then need "Alias" as a way for us to say that Bar *is* a Foo.
+	Alias Kind = "Alias"
+
+	// Interface is any type that could have differing types at run time.
+	Interface Kind = "Interface"
+
+	// The remaining types are included for completeness, but are not well
+	// supported.
+	Array       Kind = "Array" // Array is just like slice, but has a fixed length.
+	Chan        Kind = "Chan"
+	Func        Kind = "Func"
+	Unknown     Kind = ""
+	Unsupported Kind = "Unsupported"
+)
+
+// Package holds package-level information.
+// Fields are public, as everything in this package, to enable consumption by
+// templates (for example). But it is strongly encouraged for code to build by
+// using the provided functions.
+type Package struct {
+	// Canonical name of this package-- its path.
+	Path string
+
+	// Short name of this package; the name that appears in the
+	// 'package x' line.
+	Name string
+
+	// Types within this package, indexed by their name (*not* including
+	// package name).
+	Types map[string]*Type
+
+	// Packages imported by this package, indexed by (canonicalized)
+	// package path.
+	Imports map[string]*Package
+}
+
+// Has returns true if the given name references a type known to this package.
+func (p *Package) Has(name string) bool {
+	_, has := p.Types[name]
+	return has
+}
+
+// Get (or add) the given type
+func (p *Package) Get(typeName string) *Type {
+	if t, ok := p.Types[typeName]; ok {
+		return t
+	}
+	if p.Path == "" {
+		// Import the standard builtin types!
+		if t, ok := builtins.Types[typeName]; ok {
+			p.Types[typeName] = t
+			return t
+		}
+	}
+	t := &Type{Name: Name{p.Path, typeName}}
+	p.Types[typeName] = t
+	return t
+}
+
+// HasImport returns true if p imports packageName. Package names include the
+// package directory.
+func (p *Package) HasImport(packageName string) bool {
+	_, has := p.Imports[packageName]
+	return has
+}
+
+// Universe is a map of all packages. The key is the package name, but you
+// should use Get() or Package() instead of direct access.
+type Universe map[string]*Package
+
+// Get returns the canonical type for the given fully-qualified name. Builtin
+// types will always be found, even if they haven't been explicitly added to
+// the map. If a non-existing type is requested, u will create (a marker for)
+// it.
+func (u Universe) Get(n Name) *Type {
+	return u.Package(n.Package).Get(n.Name)
+}
+
+// AddImports registers import lines for packageName. May be called multiple times.
+// You are responsible for canonicalizing all package paths.
+func (u Universe) AddImports(packagePath string, importPaths ...string) {
+	p := u.Package(packagePath)
+	for _, i := range importPaths {
+		p.Imports[i] = u.Package(i)
+	}
+}
+
+// Get (create if needed) the package.
+func (u Universe) Package(packagePath string) *Package {
+	if p, ok := u[packagePath]; ok {
+		return p
+	}
+	p := &Package{
+		Path:    packagePath,
+		Types:   map[string]*Type{},
+		Imports: map[string]*Package{},
+	}
+	u[packagePath] = p
+	return p
+}
+
+// Type represents a subset of possible go types.
+type Type struct {
+	// There are two general categories of types, those explicitly named
+	// and those anonymous. Named ones will have a non-empty package in the
+	// name field.
+	Name Name
+
+	// The general kind of this type.
+	Kind Kind
+
+	// If there are comment lines immediately before the type definition,
+	// they will be recorded here.
+	CommentLines string
+
+	// If Kind == Struct
+	Members []Member
+
+	// If Kind == Map, Slice, Pointer, or Chan
+	Elem *Type
+
+	// If Kind == Map, this is the map's key type.
+	Key *Type
+
+	// If Kind == Alias, this is the underlying type.
+	Underlying *Type
+
+	// If Kind == Interface, this is the list of all required functions.
+	// Otherwise, if this is a named type, this is the list of methods that
+	// type has. (All elements will have Kind=="Func")
+	Methods []*Type
+
+	// If Kind == func, this is the signature of the function.
+	Signature *Signature
+
+	// TODO: Add:
+	// * channel direction
+	// * array length
+}
+
+// String returns the name of the type.
+func (t *Type) String() string {
+	return t.Name.String()
+}
+
+// A single struct member
+type Member struct {
+	// The name of the member.
+	Name string
+
+	// If the member is embedded (anonymous) this will be true, and the
+	// Name will be the type name.
+	Embedded bool
+
+	// If there are comment lines immediately before the member in the type
+	// definition, they will be recorded here.
+	CommentLines string
+
+	// If there are tags along with this member, they will be saved here.
+	Tags string
+
+	// The type of this member.
+	Type *Type
+}
+
+// String returns the name and type of the member.
+func (m Member) String() string {
+	return m.Name + " " + m.Type.String()
+}
+
+// Signature is a function's signature.
+type Signature struct {
+	// TODO: store the parameter names, not just types.
+
+	// If a method of some type, this is the type it's a member of.
+	Receiver   *Type
+	Parameters []*Type
+	Results    []*Type
+
+	// True if the last in parameter is of the form ...T.
+	Variadic bool
+
+	// If there are comment lines immediately before this
+	// signature/method/function declaration, they will be recorded here.
+	CommentLines string
+}
+
+// Built in types.
+var (
+	String = &Type{
+		Name: Name{Name: "string"},
+		Kind: Builtin,
+	}
+	Int64 = &Type{
+		Name: Name{Name: "int64"},
+		Kind: Builtin,
+	}
+	Int32 = &Type{
+		Name: Name{Name: "int32"},
+		Kind: Builtin,
+	}
+	Int16 = &Type{
+		Name: Name{Name: "int16"},
+		Kind: Builtin,
+	}
+	Int = &Type{
+		Name: Name{Name: "int"},
+		Kind: Builtin,
+	}
+	Uint64 = &Type{
+		Name: Name{Name: "uint64"},
+		Kind: Builtin,
+	}
+	Uint32 = &Type{
+		Name: Name{Name: "uint32"},
+		Kind: Builtin,
+	}
+	Uint16 = &Type{
+		Name: Name{Name: "uint16"},
+		Kind: Builtin,
+	}
+	Uint = &Type{
+		Name: Name{Name: "uint"},
+		Kind: Builtin,
+	}
+	Bool = &Type{
+		Name: Name{Name: "bool"},
+		Kind: Builtin,
+	}
+	Byte = &Type{
+		Name: Name{Name: "byte"},
+		Kind: Builtin,
+	}
+
+	builtins = &Package{
+		Types: map[string]*Type{
+			"bool":   Bool,
+			"string": String,
+			"int":    Int,
+			"int64":  Int64,
+			"int32":  Int32,
+			"int16":  Int16,
+			"int8":   Byte,
+			"uint":   Uint,
+			"uint64": Uint64,
+			"uint32": Uint32,
+			"uint16": Uint16,
+			"uint8":  Byte,
+			"byte":   Byte,
+		},
+		Imports: map[string]*Package{},
+		Path:    "",
+		Name:    "",
+	}
+)

cmd/libs/go2idl/types/types_test.go

+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+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 types
+
+import (
+	"testing"
+)
+
+func TestGetBuiltin(t *testing.T) {
+	u := Universe{}
+	if builtinPkg := u.Package(""); builtinPkg.Has("string") {
+		t.Errorf("Expected builtin package to not have builtins until they're asked for explicitly. %#v", builtinPkg)
+	}
+	s := u.Get(Name{"", "string"})
+	if s != String {
+		t.Errorf("Expected canonical string type.")
+	}
+	if builtinPkg := u.Package(""); !builtinPkg.Has("string") {
+		t.Errorf("Expected builtin package to exist and have builtins by default. %#v", builtinPkg)
+	}
+	if builtinPkg := u.Package(""); len(builtinPkg.Types) != 1 {
+		t.Errorf("Expected builtin package to not have builtins until they're asked for explicitly. %#v", builtinPkg)
+	}
+}
+
+func TestGetMarker(t *testing.T) {
+	u := Universe{}
+	n := Name{"path/to/package", "Foo"}
+	f := u.Get(n)
+	if f == nil || f.Name != n {
+		t.Errorf("Expected marker type.")
+	}
+}

third_party/golang/go/README.md

+# Vendored copy of go1.5.1's standard library's go/... packages.
+
+Q: Why did you do this awful vendoring?
+
+A: We need to build under go 1.3 and go 1.4 (soon to be go 1.4 and go 1.5.1). A
+version of the go/types package existed for go 1.4, but it does not have the
+same interface as the go 1.5 package, and @lavalamp had much better luck with
+the 1.5.1 package anyway.
+
+We will get rid of this as soon as there's a more standard way to do this, or
+when we roll over to supporting go 1.5 and go 1.6.
+
+Note that the packages here were not very happy about being transplated like
+this and if you do a diff you will see the changes made to get everything to
+compile.

third_party/golang/go/ast/ast_test.go

+// Copyright 2012 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 ast
+
+import (
+	"testing"
+)
+
+var comments = []struct {
+	list []string
+	text string
+}{
+	{[]string{"//"}, ""},
+	{[]string{"//   "}, ""},
+	{[]string{"//", "//", "//   "}, ""},
+	{[]string{"// foo   "}, "foo\n"},
+	{[]string{"//", "//", "// foo"}, "foo\n"},
+	{[]string{"// foo  bar  "}, "foo  bar\n"},
+	{[]string{"// foo", "// bar"}, "foo\nbar\n"},
+	{[]string{"// foo", "//", "//", "//", "// bar"}, "foo\n\nbar\n"},
+	{[]string{"// foo", "/* bar */"}, "foo\n bar\n"},
+	{[]string{"//", "//", "//", "// foo", "//", "//", "//"}, "foo\n"},
+
+	{[]string{"/**/"}, ""},
+	{[]string{"/*   */"}, ""},
+	{[]string{"/**/", "/**/", "/*   */"}, ""},
+	{[]string{"/* Foo   */"}, " Foo\n"},
+	{[]string{"/* Foo  Bar  */"}, " Foo  Bar\n"},
+	{[]string{"/* Foo*/", "/* Bar*/"}, " Foo\n Bar\n"},
+	{[]string{"/* Foo*/", "/**/", "/**/", "/**/", "// Bar"}, " Foo\n\nBar\n"},
+	{[]string{"/* Foo*/", "/*\n*/", "//", "/*\n*/", "// Bar"}, " Foo\n\nBar\n"},
+	{[]string{"/* Foo*/", "// Bar"}, " Foo\nBar\n"},
+	{[]string{"/* Foo\n Bar*/"}, " Foo\n Bar\n"},
+}
+
+func TestCommentText(t *testing.T) {
+	for i, c := range comments {
+		list := make([]*Comment, len(c.list))
+		for i, s := range c.list {
+			list[i] = &Comment{Text: s}
+		}
+
+		text := (&CommentGroup{list}).Text()
+		if text != c.text {
+			t.Errorf("case %d: got %q; expected %q", i, text, c.text)
+		}
+	}
+}

third_party/golang/go/ast/commentmap.go

+// Copyright 2012 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 ast
+
+import (
+	"bytes"
+	"fmt"
+	"k8s.io/kubernetes/third_party/golang/go/token"
+	"sort"
+)
+
+type byPos []*CommentGroup
+
+func (a byPos) Len() int           { return len(a) }
+func (a byPos) Less(i, j int) bool { return a[i].Pos() < a[j].Pos() }
+func (a byPos) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+// sortComments sorts the list of comment groups in source order.
+//
+func sortComments(list []*CommentGroup) {
+	// TODO(gri): Does it make sense to check for sorted-ness
+	//            first (because we know that sorted-ness is
+	//            very likely)?
+	if orderedList := byPos(list); !sort.IsSorted(orderedList) {
+		sort.Sort(orderedList)
+	}
+}
+
+// A CommentMap maps an AST node to a list of comment groups
+// associated with it. See NewCommentMap for a description of
+// the association.
+//
+type CommentMap map[Node][]*CommentGroup
+
+func (cmap CommentMap) addComment(n Node, c *CommentGroup) {
+	list := cmap[n]
+	if len(list) == 0 {
+		list = []*CommentGroup{c}
+	} else {
+		list = append(list, c)
+	}
+	cmap[n] = list
+}
+
+type byInterval []Node
+
+func (a byInterval) Len() int { return len(a) }
+func (a byInterval) Less(i, j int) bool {
+	pi, pj := a[i].Pos(), a[j].Pos()
+	return pi < pj || pi == pj && a[i].End() > a[j].End()
+}
+func (a byInterval) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
+
+// nodeList returns the list of nodes of the AST n in source order.
+//
+func nodeList(n Node) []Node {
+	var list []Node
+	Inspect(n, func(n Node) bool {
+		// don't collect comments
+		switch n.(type) {
+		case nil, *CommentGroup, *Comment:
+			return false
+		}
+		list = append(list, n)
+		return true
+	})
+	// Note: The current implementation assumes that Inspect traverses the
+	//       AST in depth-first and thus _source_ order. If AST traversal
+	//       does not follow source order, the sorting call below will be
+	//       required.
+	// sort.Sort(byInterval(list))
+	return list
+}
+
+// A commentListReader helps iterating through a list of comment groups.
+//
+type commentListReader struct {
+	fset     *token.FileSet
+	list     []*CommentGroup
+	index    int
+	comment  *CommentGroup  // comment group at current index
+	pos, end token.Position // source interval of comment group at current index
+}
+
+func (r *commentListReader) eol() bool {
+	return r.index >= len(r.list)
+}
+
+func (r *commentListReader) next() {
+	if !r.eol() {
+		r.comment = r.list[r.index]
+		r.pos = r.fset.Position(r.comment.Pos())
+		r.end = r.fset.Position(r.comment.End())
+		r.index++
+	}
+}
+
+// A nodeStack keeps track of nested nodes.
+// A node lower on the stack lexically contains the nodes higher on the stack.
+//
+type nodeStack []Node
+
+// push pops all nodes that appear lexically before n
+// and then pushes n on the stack.
+//
+func (s *nodeStack) push(n Node) {
+	s.pop(n.Pos())
+	*s = append((*s), n)
+}
+
+// pop pops all nodes that appear lexically before pos
+// (i.e., whose lexical extent has ended before or at pos).
+// It returns the last node popped.
+//
+func (s *nodeStack) pop(pos token.Pos) (top Node) {
+	i := len(*s)
+	for i > 0 && (*s)[i-1].End() <= pos {
+		top = (*s)[i-1]
+		i--
+	}
+	*s = (*s)[0:i]
+	return top
+}
+
+// NewCommentMap creates a new comment map by associating comment groups
+// of the comments list with the nodes of the AST specified by node.
+//
+// A comment group g is associated with a node n if:
+//
+//   - g starts on the same line as n ends
+//   - g starts on the line immediately following n, and there is
+//     at least one empty line after g and before the next node
+//   - g starts before n and is not associated to the node before n
+//     via the previous rules
+//
+// NewCommentMap tries to associate a comment group to the "largest"
+// node possible: For instance, if the comment is a line comment
+// trailing an assignment, the comment is associated with the entire
+// assignment rather than just the last operand in the assignment.
+//
+func NewCommentMap(fset *token.FileSet, node Node, comments []*CommentGroup) CommentMap {
+	if len(comments) == 0 {
+		return nil // no comments to map
+	}
+
+	cmap := make(CommentMap)
+
+	// set up comment reader r
+	tmp := make([]*CommentGroup, len(comments))
+	copy(tmp, comments) // don't change incoming comments
+	sortComments(tmp)
+	r := commentListReader{fset: fset, list: tmp} // !r.eol() because len(comments) > 0
+	r.next()
+
+	// create node list in lexical order
+	nodes := nodeList(node)
+	nodes = append(nodes, nil) // append sentinel
+
+	// set up iteration variables
+	var (
+		p     Node           // previous node
+		pend  token.Position // end of p
+		pg    Node           // previous node group (enclosing nodes of "importance")
+		pgend token.Position // end of pg
+		stack nodeStack      // stack of node groups
+	)
+
+	for _, q := range nodes {
+		var qpos token.Position
+		if q != nil {
+			qpos = fset.Position(q.Pos()) // current node position
+		} else {
+			// set fake sentinel position to infinity so that
+			// all comments get processed before the sentinel
+			const infinity = 1 << 30
+			qpos.Offset = infinity
+			qpos.Line = infinity
+		}
+
+		// process comments before current node
+		for r.end.Offset <= qpos.Offset {
+			// determine recent node group
+			if top := stack.pop(r.comment.Pos()); top != nil {
+				pg = top
+				pgend = fset.Position(pg.End())
+			}
+			// Try to associate a comment first with a node group
+			// (i.e., a node of "importance" such as a declaration);
+			// if that fails, try to associate it with the most recent
+			// node.
+			// TODO(gri) try to simplify the logic below
+			var assoc Node
+			switch {
+			case pg != nil &&
+				(pgend.Line == r.pos.Line ||
+					pgend.Line+1 == r.pos.Line && r.end.Line+1 < qpos.Line):
+				// 1) comment starts on same line as previous node group ends, or
+				// 2) comment starts on the line immediately after the
+				//    previous node group and there is an empty line before
+				//    the current node
+				// => associate comment with previous node group
+				assoc = pg
+			case p != nil &&
+				(pend.Line == r.pos.Line ||
+					pend.Line+1 == r.pos.Line && r.end.Line+1 < qpos.Line ||
+					q == nil):
+				// same rules apply as above for p rather than pg,
+				// but also associate with p if we are at the end (q == nil)
+				assoc = p
+			default:
+				// otherwise, associate comment with current node
+				if q == nil {
+					// we can only reach here if there was no p
+					// which would imply that there were no nodes
+					panic("internal error: no comments should be associated with sentinel")
+				}
+				assoc = q
+			}
+			cmap.addComment(assoc, r.comment)
+			if r.eol() {
+				return cmap
+			}
+			r.next()
+		}
+
+		// update previous node
+		p = q
+		pend = fset.Position(p.End())
+
+		// update previous node group if we see an "important" node
+		switch q.(type) {
+		case *File, *Field, Decl, Spec, Stmt:
+			stack.push(q)
+		}
+	}
+
+	return cmap
+}
+
+// Update replaces an old node in the comment map with the new node
+// and returns the new node. Comments that were associated with the
+// old node are associated with the new node.
+//
+func (cmap CommentMap) Update(old, new Node) Node {
+	if list := cmap[old]; len(list) > 0 {
+		delete(cmap, old)
+		cmap[new] = append(cmap[new], list...)
+	}
+	return new
+}
+
+// Filter returns a new comment map consisting of only those
+// entries of cmap for which a corresponding node exists in
+// the AST specified by node.
+//
+func (cmap CommentMap) Filter(node Node) CommentMap {
+	umap := make(CommentMap)
+	Inspect(node, func(n Node) bool {
+		if g := cmap[n]; len(g) > 0 {
+			umap[n] = g
+		}
+		return true
+	})
+	return umap
+}
+
+// Comments returns the list of comment groups in the comment map.
+// The result is sorted is source order.
+//
+func (cmap CommentMap) Comments() []*CommentGroup {
+	list := make([]*CommentGroup, 0, len(cmap))
+	for _, e := range cmap {
+		list = append(list, e...)
+	}
+	sortComments(list)
+	return list
+}
+
+func summary(list []*CommentGroup) string {
+	const maxLen = 40
+	var buf bytes.Buffer
+
+	// collect comments text
+loop:
+	for _, group := range list {
+		// Note: CommentGroup.Text() does too much work for what we
+		//       need and would only replace this innermost loop.
+		//       Just do it explicitly.
+		for _, comment := range group.List {
+			if buf.Len() >= maxLen {
+				break loop
+			}
+			buf.WriteString(comment.Text)
+		}
+	}
+
+	// truncate if too long
+	if buf.Len() > maxLen {
+		buf.Truncate(maxLen - 3)
+		buf.WriteString("...")
+	}
+
+	// replace any invisibles with blanks
+	bytes := buf.Bytes()
+	for i, b := range bytes {
+		switch b {
+		case '\t', '\n', '\r':
+			bytes[i] = ' '
+		}
+	}
+
+	return string(bytes)
+}
+
+func (cmap CommentMap) String() string {
+	var buf bytes.Buffer
+	fmt.Fprintln(&buf, "CommentMap {")
+	for node, comment := range cmap {
+		// print name of identifiers; print node type for other nodes
+		var s string
+		if ident, ok := node.(*Ident); ok {
+			s = ident.Name
+		} else {
+			s = fmt.Sprintf("%T", node)
+		}
+		fmt.Fprintf(&buf, "\t%p  %20s:  %s\n", node, s, summary(comment))
+	}
+	fmt.Fprintln(&buf, "}")
+	return buf.String()
+}

third_party/golang/go/ast/commentmap_test.go

+// Copyright 2012 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.
+
+// To avoid a cyclic dependency with go/parser, this file is in a separate package.
+
+package ast_test
+
+import (
+	"bytes"
+	"fmt"
+	. "k8s.io/kubernetes/third_party/golang/go/ast"
+	"k8s.io/kubernetes/third_party/golang/go/parser"
+	"k8s.io/kubernetes/third_party/golang/go/token"
+	"sort"
+	"testing"
+)
+
+const src = `
+// the very first comment
+
+// package p
+package p /* the name is p */
+
+// imports
+import (
+	"bytes"     // bytes
+	"fmt"       // fmt
+	"k8s.io/kubernetes/third_party/golang/go/ast"
+	"k8s.io/kubernetes/third_party/golang/go/parser"
+)
+
+// T
+type T struct {
+	a, b, c int // associated with a, b, c
+	// associated with x, y
+	x, y float64    // float values
+	z    complex128 // complex value
+}
+// also associated with T
+
+// x
+var x = 0 // x = 0
+// also associated with x
+
+// f1
+func f1() {
+	/* associated with s1 */
+	s1()
+	// also associated with s1
+	
+	// associated with s2
+	
+	// also associated with s2
+	s2() // line comment for s2
+}
+// associated with f1
+// also associated with f1
+
+// associated with f2
+
+// f2
+func f2() {
+}
+
+func f3() {
+	i := 1 /* 1 */ + 2 // addition
+	_ = i
+}
+
+// the very last comment
+`
+
+// res maps a key of the form "line number: node type"
+// to the associated comments' text.
+//
+var res = map[string]string{
+	" 5: *ast.File":       "the very first comment\npackage p\n",
+	" 5: *ast.Ident":      " the name is p\n",
+	" 8: *ast.GenDecl":    "imports\n",
+	" 9: *ast.ImportSpec": "bytes\n",
+	"10: *ast.ImportSpec": "fmt\n",
+	"16: *ast.GenDecl":    "T\nalso associated with T\n",
+	"17: *ast.Field":      "associated with a, b, c\n",
+	"19: *ast.Field":      "associated with x, y\nfloat values\n",
+	"20: *ast.Field":      "complex value\n",
+	"25: *ast.GenDecl":    "x\nx = 0\nalso associated with x\n",
+	"29: *ast.FuncDecl":   "f1\nassociated with f1\nalso associated with f1\n",
+	"31: *ast.ExprStmt":   " associated with s1\nalso associated with s1\n",
+	"37: *ast.ExprStmt":   "associated with s2\nalso associated with s2\nline comment for s2\n",
+	"45: *ast.FuncDecl":   "associated with f2\nf2\n",
+	"49: *ast.AssignStmt": "addition\n",
+	"49: *ast.BasicLit":   " 1\n",
+	"50: *ast.Ident":      "the very last comment\n",
+}
+
+func ctext(list []*CommentGroup) string {
+	var buf bytes.Buffer
+	for _, g := range list {
+		buf.WriteString(g.Text())
+	}
+	return buf.String()
+}
+
+func TestCommentMap(t *testing.T) {
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "", src, parser.ParseComments)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cmap := NewCommentMap(fset, f, f.Comments)
+
+	// very correct association of comments
+	for n, list := range cmap {
+		key := fmt.Sprintf("%2d: %T", fset.Position(n.Pos()).Line, n)
+		got := ctext(list)
+		want := res[key]
+		if got != want {
+			t.Errorf("%s: got %q; want %q", key, got, want)
+		}
+	}
+
+	// verify that no comments got lost
+	if n := len(cmap.Comments()); n != len(f.Comments) {
+		t.Errorf("got %d comment groups in map; want %d", n, len(f.Comments))
+	}
+
+	// support code to update test:
+	// set genMap to true to generate res map
+	const genMap = false
+	if genMap {
+		out := make([]string, 0, len(cmap))
+		for n, list := range cmap {
+			out = append(out, fmt.Sprintf("\t\"%2d: %T\":\t%q,", fset.Position(n.Pos()).Line, n, ctext(list)))
+		}
+		sort.Strings(out)
+		for _, s := range out {
+			fmt.Println(s)
+		}
+	}
+}
+
+// TODO(gri): add tests for Filter.

third_party/golang/go/ast/example_test.go

+// Copyright 2012 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 ast_test
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/format"
+	"go/parser"
+	"go/token"
+)
+
+// This example demonstrates how to inspect the AST of a Go program.
+func ExampleInspect() {
+	// src is the input for which we want to inspect the AST.
+	src := `
+package p
+const c = 1.0
+var X = f(3.14)*2 + c
+`
+
+	// Create the AST by parsing src.
+	fset := token.NewFileSet() // positions are relative to fset
+	f, err := parser.ParseFile(fset, "src.go", src, 0)
+	if err != nil {
+		panic(err)
+	}
+
+	// Inspect the AST and print all identifiers and literals.
+	ast.Inspect(f, func(n ast.Node) bool {
+		var s string
+		switch x := n.(type) {
+		case *ast.BasicLit:
+			s = x.Value
+		case *ast.Ident:
+			s = x.Name
+		}
+		if s != "" {
+			fmt.Printf("%s:\t%s\n", fset.Position(n.Pos()), s)
+		}
+		return true
+	})
+
+	// output:
+	// src.go:2:9:	p
+	// src.go:3:7:	c
+	// src.go:3:11:	1.0
+	// src.go:4:5:	X
+	// src.go:4:9:	f
+	// src.go:4:11:	3.14
+	// src.go:4:17:	2
+	// src.go:4:21:	c
+}
+
+// This example shows what an AST looks like when printed for debugging.
+func ExamplePrint() {
+	// src is the input for which we want to print the AST.
+	src := `
+package main
+func main() {
+	println("Hello, World!")
+}
+`
+
+	// Create the AST by parsing src.
+	fset := token.NewFileSet() // positions are relative to fset
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		panic(err)
+	}
+
+	// Print the AST.
+	ast.Print(fset, f)
+
+	// output:
+	//      0  *ast.File {
+	//      1  .  Package: 2:1
+	//      2  .  Name: *ast.Ident {
+	//      3  .  .  NamePos: 2:9
+	//      4  .  .  Name: "main"
+	//      5  .  }
+	//      6  .  Decls: []ast.Decl (len = 1) {
+	//      7  .  .  0: *ast.FuncDecl {
+	//      8  .  .  .  Name: *ast.Ident {
+	//      9  .  .  .  .  NamePos: 3:6
+	//     10  .  .  .  .  Name: "main"
+	//     11  .  .  .  .  Obj: *ast.Object {
+	//     12  .  .  .  .  .  Kind: func
+	//     13  .  .  .  .  .  Name: "main"
+	//     14  .  .  .  .  .  Decl: *(obj @ 7)
+	//     15  .  .  .  .  }
+	//     16  .  .  .  }
+	//     17  .  .  .  Type: *ast.FuncType {
+	//     18  .  .  .  .  Func: 3:1
+	//     19  .  .  .  .  Params: *ast.FieldList {
+	//     20  .  .  .  .  .  Opening: 3:10
+	//     21  .  .  .  .  .  Closing: 3:11
+	//     22  .  .  .  .  }
+	//     23  .  .  .  }
+	//     24  .  .  .  Body: *ast.BlockStmt {
+	//     25  .  .  .  .  Lbrace: 3:13
+	//     26  .  .  .  .  List: []ast.Stmt (len = 1) {
+	//     27  .  .  .  .  .  0: *ast.ExprStmt {
+	//     28  .  .  .  .  .  .  X: *ast.CallExpr {
+	//     29  .  .  .  .  .  .  .  Fun: *ast.Ident {
+	//     30  .  .  .  .  .  .  .  .  NamePos: 4:2
+	//     31  .  .  .  .  .  .  .  .  Name: "println"
+	//     32  .  .  .  .  .  .  .  }
+	//     33  .  .  .  .  .  .  .  Lparen: 4:9
+	//     34  .  .  .  .  .  .  .  Args: []ast.Expr (len = 1) {
+	//     35  .  .  .  .  .  .  .  .  0: *ast.BasicLit {
+	//     36  .  .  .  .  .  .  .  .  .  ValuePos: 4:10
+	//     37  .  .  .  .  .  .  .  .  .  Kind: STRING
+	//     38  .  .  .  .  .  .  .  .  .  Value: "\"Hello, World!\""
+	//     39  .  .  .  .  .  .  .  .  }
+	//     40  .  .  .  .  .  .  .  }
+	//     41  .  .  .  .  .  .  .  Ellipsis: -
+	//     42  .  .  .  .  .  .  .  Rparen: 4:25
+	//     43  .  .  .  .  .  .  }
+	//     44  .  .  .  .  .  }
+	//     45  .  .  .  .  }
+	//     46  .  .  .  .  Rbrace: 5:1
+	//     47  .  .  .  }
+	//     48  .  .  }
+	//     49  .  }
+	//     50  .  Scope: *ast.Scope {
+	//     51  .  .  Objects: map[string]*ast.Object (len = 1) {
+	//     52  .  .  .  "main": *(obj @ 11)
+	//     53  .  .  }
+	//     54  .  }
+	//     55  .  Unresolved: []*ast.Ident (len = 1) {
+	//     56  .  .  0: *(obj @ 29)
+	//     57  .  }
+	//     58  }
+}
+
+// This example illustrates how to remove a variable declaration
+// in a Go program while maintaining correct comment association
+// using an ast.CommentMap.
+func ExampleCommentMap() {
+	// src is the input for which we create the AST that we
+	// are going to manipulate.
+	src := `
+// This is the package comment.
+package main
+
+// This comment is associated with the hello constant.
+const hello = "Hello, World!" // line comment 1
+
+// This comment is associated with the foo variable.
+var foo = hello // line comment 2 
+
+// This comment is associated with the main function.
+func main() {
+	fmt.Println(hello) // line comment 3
+}
+`
+
+	// Create the AST by parsing src.
+	fset := token.NewFileSet() // positions are relative to fset
+	f, err := parser.ParseFile(fset, "src.go", src, parser.ParseComments)
+	if err != nil {
+		panic(err)
+	}
+
+	// Create an ast.CommentMap from the ast.File's comments.
+	// This helps keeping the association between comments
+	// and AST nodes.
+	cmap := ast.NewCommentMap(fset, f, f.Comments)
+
+	// Remove the first variable declaration from the list of declarations.
+	f.Decls = removeFirstVarDecl(f.Decls)
+
+	// Use the comment map to filter comments that don't belong anymore
+	// (the comments associated with the variable declaration), and create
+	// the new comments list.
+	f.Comments = cmap.Filter(f).Comments()
+
+	// Print the modified AST.
+	var buf bytes.Buffer
+	if err := format.Node(&buf, fset, f); err != nil {
+		panic(err)
+	}
+	fmt.Printf("%s", buf.Bytes())
+
+	// output:
+	// // This is the package comment.
+	// package main
+	//
+	// // This comment is associated with the hello constant.
+	// const hello = "Hello, World!" // line comment 1
+	//
+	// // This comment is associated with the main function.
+	// func main() {
+	// 	fmt.Println(hello) // line comment 3
+	// }
+}
+
+func removeFirstVarDecl(list []ast.Decl) []ast.Decl {
+	for i, decl := range list {
+		if gen, ok := decl.(*ast.GenDecl); ok && gen.Tok == token.VAR {
+			copy(list[i:], list[i+1:])
+			return list[:len(list)-1]
+		}
+	}
+	panic("variable declaration not found")
+}

third_party/golang/go/ast/filter_test.go

+// Copyright 2013 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.
+
+// To avoid a cyclic dependency with go/parser, this file is in a separate package.
+
+package ast_test
+
+import (
+	"bytes"
+	"go/ast"
+	"go/format"
+	"go/parser"
+	"go/token"
+	"testing"
+)
+
+const input = `package p
+
+type t1 struct{}
+type t2 struct{}
+
+func f1() {}
+func f1() {}
+func f2() {}
+
+func (*t1) f1() {}
+func (t1) f1() {}
+func (t1) f2() {}
+
+func (t2) f1() {}
+func (t2) f2() {}
+func (x *t2) f2() {}
+`
+
+// Calling ast.MergePackageFiles with ast.FilterFuncDuplicates
+// keeps a duplicate entry with attached documentation in favor
+// of one without, and it favors duplicate entries appearing
+// later in the source over ones appearing earlier. This is why
+// (*t2).f2 is kept and t2.f2 is eliminated in this test case.
+//
+const golden = `package p
+
+type t1 struct{}
+type t2 struct{}
+
+func f1() {}
+func f2() {}
+
+func (t1) f1() {}
+func (t1) f2() {}
+
+func (t2) f1() {}
+
+func (x *t2) f2() {}
+`
+
+func TestFilterDuplicates(t *testing.T) {
+	// parse input
+	fset := token.NewFileSet()
+	file, err := parser.ParseFile(fset, "", input, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// create package
+	files := map[string]*ast.File{"": file}
+	pkg, err := ast.NewPackage(fset, files, nil, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// filter
+	merged := ast.MergePackageFiles(pkg, ast.FilterFuncDuplicates)
+
+	// pretty-print
+	var buf bytes.Buffer
+	if err := format.Node(&buf, fset, merged); err != nil {
+		t.Fatal(err)
+	}
+	output := buf.String()
+
+	if output != golden {
+		t.Errorf("incorrect output:\n%s", output)
+	}
+}

third_party/golang/go/ast/import.go

+// Copyright 2011 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 ast
+
+import (
+	"k8s.io/kubernetes/third_party/golang/go/token"
+	"sort"
+	"strconv"
+)
+
+// SortImports sorts runs of consecutive import lines in import blocks in f.
+// It also removes duplicate imports when it is possible to do so without data loss.
+func SortImports(fset *token.FileSet, f *File) {
+	for _, d := range f.Decls {
+		d, ok := d.(*GenDecl)
+		if !ok || d.Tok != token.IMPORT {
+			// Not an import declaration, so we're done.
+			// Imports are always first.
+			break
+		}
+
+		if !d.Lparen.IsValid() {
+			// Not a block: sorted by default.
+			continue
+		}
+
+		// Identify and sort runs of specs on successive lines.
+		i := 0
+		specs := d.Specs[:0]
+		for j, s := range d.Specs {
+			if j > i && fset.Position(s.Pos()).Line > 1+fset.Position(d.Specs[j-1].End()).Line {
+				// j begins a new run.  End this one.
+				specs = append(specs, sortSpecs(fset, f, d.Specs[i:j])...)
+				i = j
+			}
+		}
+		specs = append(specs, sortSpecs(fset, f, d.Specs[i:])...)
+		d.Specs = specs
+
+		// Deduping can leave a blank line before the rparen; clean that up.
+		if len(d.Specs) > 0 {
+			lastSpec := d.Specs[len(d.Specs)-1]
+			lastLine := fset.Position(lastSpec.Pos()).Line
+			if rParenLine := fset.Position(d.Rparen).Line; rParenLine > lastLine+1 {
+				fset.File(d.Rparen).MergeLine(rParenLine - 1)
+			}
+		}
+	}
+}
+
+func importPath(s Spec) string {
+	t, err := strconv.Unquote(s.(*ImportSpec).Path.Value)
+	if err == nil {
+		return t
+	}
+	return ""
+}
+
+func importName(s Spec) string {
+	n := s.(*ImportSpec).Name
+	if n == nil {
+		return ""
+	}
+	return n.Name
+}
+
+func importComment(s Spec) string {
+	c := s.(*ImportSpec).Comment
+	if c == nil {
+		return ""
+	}
+	return c.Text()
+}
+
+// collapse indicates whether prev may be removed, leaving only next.
+func collapse(prev, next Spec) bool {
+	if importPath(next) != importPath(prev) || importName(next) != importName(prev) {
+		return false
+	}
+	return prev.(*ImportSpec).Comment == nil
+}
+
+type posSpan struct {
+	Start token.Pos
+	End   token.Pos
+}
+
+func sortSpecs(fset *token.FileSet, f *File, specs []Spec) []Spec {
+	// Can't short-circuit here even if specs are already sorted,
+	// since they might yet need deduplication.
+	// A lone import, however, may be safely ignored.
+	if len(specs) <= 1 {
+		return specs
+	}
+
+	// Record positions for specs.
+	pos := make([]posSpan, len(specs))
+	for i, s := range specs {
+		pos[i] = posSpan{s.Pos(), s.End()}
+	}
+
+	// Identify comments in this range.
+	// Any comment from pos[0].Start to the final line counts.
+	lastLine := fset.Position(pos[len(pos)-1].End).Line
+	cstart := len(f.Comments)
+	cend := len(f.Comments)
+	for i, g := range f.Comments {
+		if g.Pos() < pos[0].Start {
+			continue
+		}
+		if i < cstart {
+			cstart = i
+		}
+		if fset.Position(g.End()).Line > lastLine {
+			cend = i
+			break
+		}
+	}
+	comments := f.Comments[cstart:cend]
+
+	// Assign each comment to the import spec preceding it.
+	importComment := map[*ImportSpec][]*CommentGroup{}
+	specIndex := 0
+	for _, g := range comments {
+		for specIndex+1 < len(specs) && pos[specIndex+1].Start <= g.Pos() {
+			specIndex++
+		}
+		s := specs[specIndex].(*ImportSpec)
+		importComment[s] = append(importComment[s], g)
+	}
+
+	// Sort the import specs by import path.
+	// Remove duplicates, when possible without data loss.
+	// Reassign the import paths to have the same position sequence.
+	// Reassign each comment to abut the end of its spec.
+	// Sort the comments by new position.
+	sort.Sort(byImportSpec(specs))
+
+	// Dedup. Thanks to our sorting, we can just consider
+	// adjacent pairs of imports.
+	deduped := specs[:0]
+	for i, s := range specs {
+		if i == len(specs)-1 || !collapse(s, specs[i+1]) {
+			deduped = append(deduped, s)
+		} else {
+			p := s.Pos()
+			fset.File(p).MergeLine(fset.Position(p).Line)
+		}
+	}
+	specs = deduped
+
+	// Fix up comment positions
+	for i, s := range specs {
+		s := s.(*ImportSpec)
+		if s.Name != nil {
+			s.Name.NamePos = pos[i].Start
+		}
+		s.Path.ValuePos = pos[i].Start
+		s.EndPos = pos[i].End
+		for _, g := range importComment[s] {
+			for _, c := range g.List {
+				c.Slash = pos[i].End
+			}
+		}
+	}
+
+	sort.Sort(byCommentPos(comments))
+
+	return specs
+}
+
+type byImportSpec []Spec // slice of *ImportSpec
+
+func (x byImportSpec) Len() int      { return len(x) }
+func (x byImportSpec) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+func (x byImportSpec) Less(i, j int) bool {
+	ipath := importPath(x[i])
+	jpath := importPath(x[j])
+	if ipath != jpath {
+		return ipath < jpath
+	}
+	iname := importName(x[i])
+	jname := importName(x[j])
+	if iname != jname {
+		return iname < jname
+	}
+	return importComment(x[i]) < importComment(x[j])
+}
+
+type byCommentPos []*CommentGroup
+
+func (x byCommentPos) Len() int           { return len(x) }
+func (x byCommentPos) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+func (x byCommentPos) Less(i, j int) bool { return x[i].Pos() < x[j].Pos() }

third_party/golang/go/ast/print.go

+// Copyright 2010 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.
+
+// This file contains printing support for ASTs.
+
+package ast
+
+import (
+	"fmt"
+	"k8s.io/kubernetes/third_party/golang/go/token"
+	"io"
+	"os"
+	"reflect"
+)
+
+// A FieldFilter may be provided to Fprint to control the output.
+type FieldFilter func(name string, value reflect.Value) bool
+
+// NotNilFilter returns true for field values that are not nil;
+// it returns false otherwise.
+func NotNilFilter(_ string, v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return !v.IsNil()
+	}
+	return true
+}
+
+// Fprint prints the (sub-)tree starting at AST node x to w.
+// If fset != nil, position information is interpreted relative
+// to that file set. Otherwise positions are printed as integer
+// values (file set specific offsets).
+//
+// A non-nil FieldFilter f may be provided to control the output:
+// struct fields for which f(fieldname, fieldvalue) is true are
+// printed; all others are filtered from the output. Unexported
+// struct fields are never printed.
+//
+func Fprint(w io.Writer, fset *token.FileSet, x interface{}, f FieldFilter) (err error) {
+	// setup printer
+	p := printer{
+		output: w,
+		fset:   fset,
+		filter: f,
+		ptrmap: make(map[interface{}]int),
+		last:   '\n', // force printing of line number on first line
+	}
+
+	// install error handler
+	defer func() {
+		if e := recover(); e != nil {
+			err = e.(localError).err // re-panics if it's not a localError
+		}
+	}()
+
+	// print x
+	if x == nil {
+		p.printf("nil\n")
+		return
+	}
+	p.print(reflect.ValueOf(x))
+	p.printf("\n")
+
+	return
+}
+
+// Print prints x to standard output, skipping nil fields.
+// Print(fset, x) is the same as Fprint(os.Stdout, fset, x, NotNilFilter).
+func Print(fset *token.FileSet, x interface{}) error {
+	return Fprint(os.Stdout, fset, x, NotNilFilter)
+}
+
+type printer struct {
+	output io.Writer
+	fset   *token.FileSet
+	filter FieldFilter
+	ptrmap map[interface{}]int // *T -> line number
+	indent int                 // current indentation level
+	last   byte                // the last byte processed by Write
+	line   int                 // current line number
+}
+
+var indent = []byte(".  ")
+
+func (p *printer) Write(data []byte) (n int, err error) {
+	var m int
+	for i, b := range data {
+		// invariant: data[0:n] has been written
+		if b == '\n' {
+			m, err = p.output.Write(data[n : i+1])
+			n += m
+			if err != nil {
+				return
+			}
+			p.line++
+		} else if p.last == '\n' {
+			_, err = fmt.Fprintf(p.output, "%6d  ", p.line)
+			if err != nil {
+				return
+			}
+			for j := p.indent; j > 0; j-- {
+				_, err = p.output.Write(indent)
+				if err != nil {
+					return
+				}
+			}
+		}
+		p.last = b
+	}
+	if len(data) > n {
+		m, err = p.output.Write(data[n:])
+		n += m
+	}
+	return
+}
+
+// localError wraps locally caught errors so we can distinguish
+// them from genuine panics which we don't want to return as errors.
+type localError struct {
+	err error
+}
+
+// printf is a convenience wrapper that takes care of print errors.
+func (p *printer) printf(format string, args ...interface{}) {
+	if _, err := fmt.Fprintf(p, format, args...); err != nil {
+		panic(localError{err})
+	}
+}
+
+// Implementation note: Print is written for AST nodes but could be
+// used to print arbitrary data structures; such a version should
+// probably be in a different package.
+//
+// Note: This code detects (some) cycles created via pointers but
+// not cycles that are created via slices or maps containing the
+// same slice or map. Code for general data structures probably
+// should catch those as well.
+
+func (p *printer) print(x reflect.Value) {
+	if !NotNilFilter("", x) {
+		p.printf("nil")
+		return
+	}
+
+	switch x.Kind() {
+	case reflect.Interface:
+		p.print(x.Elem())
+
+	case reflect.Map:
+		p.printf("%s (len = %d) {", x.Type(), x.Len())
+		if x.Len() > 0 {
+			p.indent++
+			p.printf("\n")
+			for _, key := range x.MapKeys() {
+				p.print(key)
+				p.printf(": ")
+				p.print(x.MapIndex(key))
+				p.printf("\n")
+			}
+			p.indent--
+		}
+		p.printf("}")
+
+	case reflect.Ptr:
+		p.printf("*")
+		// type-checked ASTs may contain cycles - use ptrmap
+		// to keep track of objects that have been printed
+		// already and print the respective line number instead
+		ptr := x.Interface()
+		if line, exists := p.ptrmap[ptr]; exists {
+			p.printf("(obj @ %d)", line)
+		} else {
+			p.ptrmap[ptr] = p.line
+			p.print(x.Elem())
+		}
+
+	case reflect.Array:
+		p.printf("%s {", x.Type())
+		if x.Len() > 0 {
+			p.indent++
+			p.printf("\n")
+			for i, n := 0, x.Len(); i < n; i++ {
+				p.printf("%d: ", i)
+				p.print(x.Index(i))
+				p.printf("\n")
+			}
+			p.indent--
+		}
+		p.printf("}")
+
+	case reflect.Slice:
+		if s, ok := x.Interface().([]byte); ok {
+			p.printf("%#q", s)
+			return
+		}
+		p.printf("%s (len = %d) {", x.Type(), x.Len())
+		if x.Len() > 0 {
+			p.indent++
+			p.printf("\n")
+			for i, n := 0, x.Len(); i < n; i++ {
+				p.printf("%d: ", i)
+				p.print(x.Index(i))
+				p.printf("\n")
+			}
+			p.indent--
+		}
+		p.printf("}")
+
+	case reflect.Struct:
+		t := x.Type()
+		p.printf("%s {", t)
+		p.indent++
+		first := true
+		for i, n := 0, t.NumField(); i < n; i++ {
+			// exclude non-exported fields because their
+			// values cannot be accessed via reflection
+			if name := t.Field(i).Name; IsExported(name) {
+				value := x.Field(i)
+				if p.filter == nil || p.filter(name, value) {
+					if first {
+						p.printf("\n")
+						first = false
+					}
+					p.printf("%s: ", name)
+					p.print(value)
+					p.printf("\n")
+				}
+			}
+		}
+		p.indent--
+		p.printf("}")
+
+	default:
+		v := x.Interface()
+		switch v := v.(type) {
+		case string:
+			// print strings in quotes
+			p.printf("%q", v)
+			return
+		case token.Pos:
+			// position values can be printed nicely if we have a file set
+			if p.fset != nil {
+				p.printf("%s", p.fset.Position(v))
+				return
+			}
+		}
+		// default
+		p.printf("%v", v)
+	}
+}

third_party/golang/go/ast/print_test.go

+// Copyright 2011 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 ast
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
+
+var tests = []struct {
+	x interface{} // x is printed as s
+	s string
+}{
+	// basic types
+	{nil, "0  nil"},
+	{true, "0  true"},
+	{42, "0  42"},
+	{3.14, "0  3.14"},
+	{1 + 2.718i, "0  (1+2.718i)"},
+	{"foobar", "0  \"foobar\""},
+
+	// maps
+	{map[Expr]string{}, `0  map[ast.Expr]string (len = 0) {}`},
+	{map[string]int{"a": 1},
+		`0  map[string]int (len = 1) {
+		1  .  "a": 1
+		2  }`},
+
+	// pointers
+	{new(int), "0  *0"},
+
+	// arrays
+	{[0]int{}, `0  [0]int {}`},
+	{[3]int{1, 2, 3},
+		`0  [3]int {
+		1  .  0: 1
+		2  .  1: 2
+		3  .  2: 3
+		4  }`},
+	{[...]int{42},
+		`0  [1]int {
+		1  .  0: 42
+		2  }`},
+
+	// slices
+	{[]int{}, `0  []int (len = 0) {}`},
+	{[]int{1, 2, 3},
+		`0  []int (len = 3) {
+		1  .  0: 1
+		2  .  1: 2
+		3  .  2: 3
+		4  }`},
+
+	// structs
+	{struct{}{}, `0  struct {} {}`},
+	{struct{ x int }{007}, `0  struct { x int } {}`},
+	{struct{ X, y int }{42, 991},
+		`0  struct { X int; y int } {
+		1  .  X: 42
+		2  }`},
+	{struct{ X, Y int }{42, 991},
+		`0  struct { X int; Y int } {
+		1  .  X: 42
+		2  .  Y: 991
+		3  }`},
+}
+
+// Split s into lines, trim whitespace from all lines, and return
+// the concatenated non-empty lines.
+func trim(s string) string {
+	lines := strings.Split(s, "\n")
+	i := 0
+	for _, line := range lines {
+		line = strings.TrimSpace(line)
+		if line != "" {
+			lines[i] = line
+			i++
+		}
+	}
+	return strings.Join(lines[0:i], "\n")
+}
+
+func TestPrint(t *testing.T) {
+	var buf bytes.Buffer
+	for _, test := range tests {
+		buf.Reset()
+		if err := Fprint(&buf, nil, test.x, nil); err != nil {
+			t.Errorf("Fprint failed: %s", err)
+		}
+		if s, ts := trim(buf.String()), trim(test.s); s != ts {
+			t.Errorf("got:\n%s\nexpected:\n%s\n", s, ts)
+		}
+	}
+}

third_party/golang/go/ast/resolve.go

+// Copyright 2011 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.
+
+// This file implements NewPackage.
+
+package ast
+
+import (
+	"fmt"
+	"k8s.io/kubernetes/third_party/golang/go/scanner"
+	"k8s.io/kubernetes/third_party/golang/go/token"
+	"strconv"
+)
+
+type pkgBuilder struct {
+	fset   *token.FileSet
+	errors scanner.ErrorList
+}
+
+func (p *pkgBuilder) error(pos token.Pos, msg string) {
+	p.errors.Add(p.fset.Position(pos), msg)
+}
+
+func (p *pkgBuilder) errorf(pos token.Pos, format string, args ...interface{}) {
+	p.error(pos, fmt.Sprintf(format, args...))
+}
+
+func (p *pkgBuilder) declare(scope, altScope *Scope, obj *Object) {
+	alt := scope.Insert(obj)
+	if alt == nil && altScope != nil {
+		// see if there is a conflicting declaration in altScope
+		alt = altScope.Lookup(obj.Name)
+	}
+	if alt != nil {
+		prevDecl := ""
+		if pos := alt.Pos(); pos.IsValid() {
+			prevDecl = fmt.Sprintf("\n\tprevious declaration at %s", p.fset.Position(pos))
+		}
+		p.error(obj.Pos(), fmt.Sprintf("%s redeclared in this block%s", obj.Name, prevDecl))
+	}
+}
+
+func resolve(scope *Scope, ident *Ident) bool {
+	for ; scope != nil; scope = scope.Outer {
+		if obj := scope.Lookup(ident.Name); obj != nil {
+			ident.Obj = obj
+			return true
+		}
+	}
+	return false
+}
+
+// An Importer resolves import paths to package Objects.
+// The imports map records the packages already imported,
+// indexed by package id (canonical import path).
+// An Importer must determine the canonical import path and
+// check the map to see if it is already present in the imports map.
+// If so, the Importer can return the map entry.  Otherwise, the
+// Importer should load the package data for the given path into
+// a new *Object (pkg), record pkg in the imports map, and then
+// return pkg.
+type Importer func(imports map[string]*Object, path string) (pkg *Object, err error)
+
+// NewPackage creates a new Package node from a set of File nodes. It resolves
+// unresolved identifiers across files and updates each file's Unresolved list
+// accordingly. If a non-nil importer and universe scope are provided, they are
+// used to resolve identifiers not declared in any of the package files. Any
+// remaining unresolved identifiers are reported as undeclared. If the files
+// belong to different packages, one package name is selected and files with
+// different package names are reported and then ignored.
+// The result is a package node and a scanner.ErrorList if there were errors.
+//
+func NewPackage(fset *token.FileSet, files map[string]*File, importer Importer, universe *Scope) (*Package, error) {
+	var p pkgBuilder
+	p.fset = fset
+
+	// complete package scope
+	pkgName := ""
+	pkgScope := NewScope(universe)
+	for _, file := range files {
+		// package names must match
+		switch name := file.Name.Name; {
+		case pkgName == "":
+			pkgName = name
+		case name != pkgName:
+			p.errorf(file.Package, "package %s; expected %s", name, pkgName)
+			continue // ignore this file
+		}
+
+		// collect top-level file objects in package scope
+		for _, obj := range file.Scope.Objects {
+			p.declare(pkgScope, nil, obj)
+		}
+	}
+
+	// package global mapping of imported package ids to package objects
+	imports := make(map[string]*Object)
+
+	// complete file scopes with imports and resolve identifiers
+	for _, file := range files {
+		// ignore file if it belongs to a different package
+		// (error has already been reported)
+		if file.Name.Name != pkgName {
+			continue
+		}
+
+		// build file scope by processing all imports
+		importErrors := false
+		fileScope := NewScope(pkgScope)
+		for _, spec := range file.Imports {
+			if importer == nil {
+				importErrors = true
+				continue
+			}
+			path, _ := strconv.Unquote(spec.Path.Value)
+			pkg, err := importer(imports, path)
+			if err != nil {
+				p.errorf(spec.Path.Pos(), "could not import %s (%s)", path, err)
+				importErrors = true
+				continue
+			}
+			// TODO(gri) If a local package name != "." is provided,
+			// global identifier resolution could proceed even if the
+			// import failed. Consider adjusting the logic here a bit.
+
+			// local name overrides imported package name
+			name := pkg.Name
+			if spec.Name != nil {
+				name = spec.Name.Name
+			}
+
+			// add import to file scope
+			if name == "." {
+				// merge imported scope with file scope
+				for _, obj := range pkg.Data.(*Scope).Objects {
+					p.declare(fileScope, pkgScope, obj)
+				}
+			} else if name != "_" {
+				// declare imported package object in file scope
+				// (do not re-use pkg in the file scope but create
+				// a new object instead; the Decl field is different
+				// for different files)
+				obj := NewObj(Pkg, name)
+				obj.Decl = spec
+				obj.Data = pkg.Data
+				p.declare(fileScope, pkgScope, obj)
+			}
+		}
+
+		// resolve identifiers
+		if importErrors {
+			// don't use the universe scope without correct imports
+			// (objects in the universe may be shadowed by imports;
+			// with missing imports, identifiers might get resolved
+			// incorrectly to universe objects)
+			pkgScope.Outer = nil
+		}
+		i := 0
+		for _, ident := range file.Unresolved {
+			if !resolve(fileScope, ident) {
+				p.errorf(ident.Pos(), "undeclared name: %s", ident.Name)
+				file.Unresolved[i] = ident
+				i++
+			}
+
+		}
+		file.Unresolved = file.Unresolved[0:i]
+		pkgScope.Outer = universe // reset universe scope
+	}
+
+	p.errors.Sort()
+	return &Package{pkgName, pkgScope, imports, files}, p.errors.Err()
+}

third_party/golang/go/ast/scope.go

+// Copyright 2009 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.
+
+// This file implements scopes and the objects they contain.
+
+package ast
+
+import (
+	"bytes"
+	"fmt"
+	"k8s.io/kubernetes/third_party/golang/go/token"
+)
+
+// A Scope maintains the set of named language entities declared
+// in the scope and a link to the immediately surrounding (outer)
+// scope.
+//
+type Scope struct {
+	Outer   *Scope
+	Objects map[string]*Object
+}
+
+// NewScope creates a new scope nested in the outer scope.
+func NewScope(outer *Scope) *Scope {
+	const n = 4 // initial scope capacity
+	return &Scope{outer, make(map[string]*Object, n)}
+}
+
+// Lookup returns the object with the given name if it is
+// found in scope s, otherwise it returns nil. Outer scopes
+// are ignored.
+//
+func (s *Scope) Lookup(name string) *Object {
+	return s.Objects[name]
+}
+
+// Insert attempts to insert a named object obj into the scope s.
+// If the scope already contains an object alt with the same name,
+// Insert leaves the scope unchanged and returns alt. Otherwise
+// it inserts obj and returns nil.
+//
+func (s *Scope) Insert(obj *Object) (alt *Object) {
+	if alt = s.Objects[obj.Name]; alt == nil {
+		s.Objects[obj.Name] = obj
+	}
+	return
+}
+
+// Debugging support
+func (s *Scope) String() string {
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "scope %p {", s)
+	if s != nil && len(s.Objects) > 0 {
+		fmt.Fprintln(&buf)
+		for _, obj := range s.Objects {
+			fmt.Fprintf(&buf, "\t%s %s\n", obj.Kind, obj.Name)
+		}
+	}
+	fmt.Fprintf(&buf, "}\n")
+	return buf.String()
+}
+
+// ----------------------------------------------------------------------------
+// Objects
+
+// An Object describes a named language entity such as a package,
+// constant, type, variable, function (incl. methods), or label.
+//
+// The Data fields contains object-specific data:
+//
+//	Kind    Data type         Data value
+//	Pkg	*types.Package    package scope
+//	Con     int               iota for the respective declaration
+//	Con     != nil            constant value
+//	Typ     *Scope            (used as method scope during type checking - transient)
+//
+type Object struct {
+	Kind ObjKind
+	Name string      // declared name
+	Decl interface{} // corresponding Field, XxxSpec, FuncDecl, LabeledStmt, AssignStmt, Scope; or nil
+	Data interface{} // object-specific data; or nil
+	Type interface{} // placeholder for type information; may be nil
+}
+
+// NewObj creates a new object of a given kind and name.
+func NewObj(kind ObjKind, name string) *Object {
+	return &Object{Kind: kind, Name: name}
+}
+
+// Pos computes the source position of the declaration of an object name.
+// The result may be an invalid position if it cannot be computed
+// (obj.Decl may be nil or not correct).
+func (obj *Object) Pos() token.Pos {
+	name := obj.Name
+	switch d := obj.Decl.(type) {
+	case *Field:
+		for _, n := range d.Names {
+			if n.Name == name {
+				return n.Pos()
+			}
+		}
+	case *ImportSpec:
+		if d.Name != nil && d.Name.Name == name {
+			return d.Name.Pos()
+		}
+		return d.Path.Pos()
+	case *ValueSpec:
+		for _, n := range d.Names {
+			if n.Name == name {
+				return n.Pos()
+			}
+		}
+	case *TypeSpec:
+		if d.Name.Name == name {
+			return d.Name.Pos()
+		}
+	case *FuncDecl:
+		if d.Name.Name == name {
+			return d.Name.Pos()
+		}
+	case *LabeledStmt:
+		if d.Label.Name == name {
+			return d.Label.Pos()
+		}
+	case *AssignStmt:
+		for _, x := range d.Lhs {
+			if ident, isIdent := x.(*Ident); isIdent && ident.Name == name {
+				return ident.Pos()
+			}
+		}
+	case *Scope:
+		// predeclared object - nothing to do for now
+	}
+	return token.NoPos
+}
+
+// ObjKind describes what an object represents.
+type ObjKind int
+
+// The list of possible Object kinds.
+const (
+	Bad ObjKind = iota // for error handling
+	Pkg                // package
+	Con                // constant
+	Typ                // type
+	Var                // variable
+	Fun                // function or method
+	Lbl                // label
+)
+
+var objKindStrings = [...]string{
+	Bad: "bad",
+	Pkg: "package",
+	Con: "const",
+	Typ: "type",
+	Var: "var",
+	Fun: "func",
+	Lbl: "label",
+}
+
+func (kind ObjKind) String() string { return objKindStrings[kind] }

third_party/golang/go/ast/walk.go

+// Copyright 2009 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 ast
+
+import "fmt"
+
+// A Visitor's Visit method is invoked for each node encountered by Walk.
+// If the result visitor w is not nil, Walk visits each of the children
+// of node with the visitor w, followed by a call of w.Visit(nil).
+type Visitor interface {
+	Visit(node Node) (w Visitor)
+}
+
+// Helper functions for common node lists. They may be empty.
+
+func walkIdentList(v Visitor, list []*Ident) {
+	for _, x := range list {
+		Walk(v, x)
+	}
+}
+
+func walkExprList(v Visitor, list []Expr) {
+	for _, x := range list {
+		Walk(v, x)
+	}
+}
+
+func walkStmtList(v Visitor, list []Stmt) {
+	for _, x := range list {
+		Walk(v, x)
+	}
+}
+
+func walkDeclList(v Visitor, list []Decl) {
+	for _, x := range list {
+		Walk(v, x)
+	}
+}
+
+// TODO(gri): Investigate if providing a closure to Walk leads to
+//            simpler use (and may help eliminate Inspect in turn).
+
+// Walk traverses an AST in depth-first order: It starts by calling
+// v.Visit(node); node must not be nil. If the visitor w returned by
+// v.Visit(node) is not nil, Walk is invoked recursively with visitor
+// w for each of the non-nil children of node, followed by a call of
+// w.Visit(nil).
+//
+func Walk(v Visitor, node Node) {
+	if v = v.Visit(node); v == nil {
+		return
+	}
+
+	// walk children
+	// (the order of the cases matches the order
+	// of the corresponding node types in ast.go)
+	switch n := node.(type) {
+	// Comments and fields
+	case *Comment:
+		// nothing to do
+
+	case *CommentGroup:
+		for _, c := range n.List {
+			Walk(v, c)
+		}
+
+	case *Field:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		walkIdentList(v, n.Names)
+		Walk(v, n.Type)
+		if n.Tag != nil {
+			Walk(v, n.Tag)
+		}
+		if n.Comment != nil {
+			Walk(v, n.Comment)
+		}
+
+	case *FieldList:
+		for _, f := range n.List {
+			Walk(v, f)
+		}
+
+	// Expressions
+	case *BadExpr, *Ident, *BasicLit:
+		// nothing to do
+
+	case *Ellipsis:
+		if n.Elt != nil {
+			Walk(v, n.Elt)
+		}
+
+	case *FuncLit:
+		Walk(v, n.Type)
+		Walk(v, n.Body)
+
+	case *CompositeLit:
+		if n.Type != nil {
+			Walk(v, n.Type)
+		}
+		walkExprList(v, n.Elts)
+
+	case *ParenExpr:
+		Walk(v, n.X)
+
+	case *SelectorExpr:
+		Walk(v, n.X)
+		Walk(v, n.Sel)
+
+	case *IndexExpr:
+		Walk(v, n.X)
+		Walk(v, n.Index)
+
+	case *SliceExpr:
+		Walk(v, n.X)
+		if n.Low != nil {
+			Walk(v, n.Low)
+		}
+		if n.High != nil {
+			Walk(v, n.High)
+		}
+		if n.Max != nil {
+			Walk(v, n.Max)
+		}
+
+	case *TypeAssertExpr:
+		Walk(v, n.X)
+		if n.Type != nil {
+			Walk(v, n.Type)
+		}
+
+	case *CallExpr:
+		Walk(v, n.Fun)
+		walkExprList(v, n.Args)
+
+	case *StarExpr:
+		Walk(v, n.X)
+
+	case *UnaryExpr:
+		Walk(v, n.X)
+
+	case *BinaryExpr:
+		Walk(v, n.X)
+		Walk(v, n.Y)
+
+	case *KeyValueExpr:
+		Walk(v, n.Key)
+		Walk(v, n.Value)
+
+	// Types
+	case *ArrayType:
+		if n.Len != nil {
+			Walk(v, n.Len)
+		}
+		Walk(v, n.Elt)
+
+	case *StructType:
+		Walk(v, n.Fields)
+
+	case *FuncType:
+		if n.Params != nil {
+			Walk(v, n.Params)
+		}
+		if n.Results != nil {
+			Walk(v, n.Results)
+		}
+
+	case *InterfaceType:
+		Walk(v, n.Methods)
+
+	case *MapType:
+		Walk(v, n.Key)
+		Walk(v, n.Value)
+
+	case *ChanType:
+		Walk(v, n.Value)
+
+	// Statements
+	case *BadStmt:
+		// nothing to do
+
+	case *DeclStmt:
+		Walk(v, n.Decl)
+
+	case *EmptyStmt:
+		// nothing to do
+
+	case *LabeledStmt:
+		Walk(v, n.Label)
+		Walk(v, n.Stmt)
+
+	case *ExprStmt:
+		Walk(v, n.X)
+
+	case *SendStmt:
+		Walk(v, n.Chan)
+		Walk(v, n.Value)
+
+	case *IncDecStmt:
+		Walk(v, n.X)
+
+	case *AssignStmt:
+		walkExprList(v, n.Lhs)
+		walkExprList(v, n.Rhs)
+
+	case *GoStmt:
+		Walk(v, n.Call)
+
+	case *DeferStmt:
+		Walk(v, n.Call)
+
+	case *ReturnStmt:
+		walkExprList(v, n.Results)
+
+	case *BranchStmt:
+		if n.Label != nil {
+			Walk(v, n.Label)
+		}
+
+	case *BlockStmt:
+		walkStmtList(v, n.List)
+
+	case *IfStmt:
+		if n.Init != nil {
+			Walk(v, n.Init)
+		}
+		Walk(v, n.Cond)
+		Walk(v, n.Body)
+		if n.Else != nil {
+			Walk(v, n.Else)
+		}
+
+	case *CaseClause:
+		walkExprList(v, n.List)
+		walkStmtList(v, n.Body)
+
+	case *SwitchStmt:
+		if n.Init != nil {
+			Walk(v, n.Init)
+		}
+		if n.Tag != nil {
+			Walk(v, n.Tag)
+		}
+		Walk(v, n.Body)
+
+	case *TypeSwitchStmt:
+		if n.Init != nil {
+			Walk(v, n.Init)
+		}
+		Walk(v, n.Assign)
+		Walk(v, n.Body)
+
+	case *CommClause:
+		if n.Comm != nil {
+			Walk(v, n.Comm)
+		}
+		walkStmtList(v, n.Body)
+
+	case *SelectStmt:
+		Walk(v, n.Body)
+
+	case *ForStmt:
+		if n.Init != nil {
+			Walk(v, n.Init)
+		}
+		if n.Cond != nil {
+			Walk(v, n.Cond)
+		}
+		if n.Post != nil {
+			Walk(v, n.Post)
+		}
+		Walk(v, n.Body)
+
+	case *RangeStmt:
+		if n.Key != nil {
+			Walk(v, n.Key)
+		}
+		if n.Value != nil {
+			Walk(v, n.Value)
+		}
+		Walk(v, n.X)
+		Walk(v, n.Body)
+
+	// Declarations
+	case *ImportSpec:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		if n.Name != nil {
+			Walk(v, n.Name)
+		}
+		Walk(v, n.Path)
+		if n.Comment != nil {
+			Walk(v, n.Comment)
+		}
+
+	case *ValueSpec:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		walkIdentList(v, n.Names)
+		if n.Type != nil {
+			Walk(v, n.Type)
+		}
+		walkExprList(v, n.Values)
+		if n.Comment != nil {
+			Walk(v, n.Comment)
+		}
+
+	case *TypeSpec:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		Walk(v, n.Name)
+		Walk(v, n.Type)
+		if n.Comment != nil {
+			Walk(v, n.Comment)
+		}
+
+	case *BadDecl:
+		// nothing to do
+
+	case *GenDecl:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		for _, s := range n.Specs {
+			Walk(v, s)
+		}
+
+	case *FuncDecl:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		if n.Recv != nil {
+			Walk(v, n.Recv)
+		}
+		Walk(v, n.Name)
+		Walk(v, n.Type)
+		if n.Body != nil {
+			Walk(v, n.Body)
+		}
+
+	// Files and packages
+	case *File:
+		if n.Doc != nil {
+			Walk(v, n.Doc)
+		}
+		Walk(v, n.Name)
+		walkDeclList(v, n.Decls)
+		// don't walk n.Comments - they have been
+		// visited already through the individual
+		// nodes
+
+	case *Package:
+		for _, f := range n.Files {
+			Walk(v, f)
+		}
+
+	default:
+		panic(fmt.Sprintf("ast.Walk: unexpected node type %T", n))
+	}
+
+	v.Visit(nil)
+}
+
+type inspector func(Node) bool
+
+func (f inspector) Visit(node Node) Visitor {
+	if f(node) {
+		return f
+	}
+	return nil
+}
+
+// Inspect traverses an AST in depth-first order: It starts by calling
+// f(node); node must not be nil. If f returns true, Inspect invokes f
+// recursively for each of the non-nil children of node, followed by a
+// call of f(nil).
+//
+func Inspect(node Node, f func(Node) bool) {
+	Walk(inspector(f), node)
+}

third_party/golang/go/build/build_test.go

+// Copyright 2011 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 build
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func TestMatch(t *testing.T) {
+	ctxt := Default
+	what := "default"
+	match := func(tag string, want map[string]bool) {
+		m := make(map[string]bool)
+		if !ctxt.match(tag, m) {
+			t.Errorf("%s context should match %s, does not", what, tag)
+		}
+		if !reflect.DeepEqual(m, want) {
+			t.Errorf("%s tags = %v, want %v", tag, m, want)
+		}
+	}
+	nomatch := func(tag string, want map[string]bool) {
+		m := make(map[string]bool)
+		if ctxt.match(tag, m) {
+			t.Errorf("%s context should NOT match %s, does", what, tag)
+		}
+		if !reflect.DeepEqual(m, want) {
+			t.Errorf("%s tags = %v, want %v", tag, m, want)
+		}
+	}
+
+	match(runtime.GOOS+","+runtime.GOARCH, map[string]bool{runtime.GOOS: true, runtime.GOARCH: true})
+	match(runtime.GOOS+","+runtime.GOARCH+",!foo", map[string]bool{runtime.GOOS: true, runtime.GOARCH: true, "foo": true})
+	nomatch(runtime.GOOS+","+runtime.GOARCH+",foo", map[string]bool{runtime.GOOS: true, runtime.GOARCH: true, "foo": true})
+
+	what = "modified"
+	ctxt.BuildTags = []string{"foo"}
+	match(runtime.GOOS+","+runtime.GOARCH, map[string]bool{runtime.GOOS: true, runtime.GOARCH: true})
+	match(runtime.GOOS+","+runtime.GOARCH+",foo", map[string]bool{runtime.GOOS: true, runtime.GOARCH: true, "foo": true})
+	nomatch(runtime.GOOS+","+runtime.GOARCH+",!foo", map[string]bool{runtime.GOOS: true, runtime.GOARCH: true, "foo": true})
+	match(runtime.GOOS+","+runtime.GOARCH+",!bar", map[string]bool{runtime.GOOS: true, runtime.GOARCH: true, "bar": true})
+	nomatch(runtime.GOOS+","+runtime.GOARCH+",bar", map[string]bool{runtime.GOOS: true, runtime.GOARCH: true, "bar": true})
+	nomatch("!", map[string]bool{})
+}
+
+func TestDotSlashImport(t *testing.T) {
+	p, err := ImportDir("testdata/other", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(p.Imports) != 1 || p.Imports[0] != "./file" {
+		t.Fatalf("testdata/other: Imports=%v, want [./file]", p.Imports)
+	}
+
+	p1, err := Import("./file", "testdata/other", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if p1.Name != "file" {
+		t.Fatalf("./file: Name=%q, want %q", p1.Name, "file")
+	}
+	dir := filepath.Clean("testdata/other/file") // Clean to use \ on Windows
+	if p1.Dir != dir {
+		t.Fatalf("./file: Dir=%q, want %q", p1.Name, dir)
+	}
+}
+
+func TestEmptyImport(t *testing.T) {
+	p, err := Import("", Default.GOROOT, FindOnly)
+	if err == nil {
+		t.Fatal(`Import("") returned nil error.`)
+	}
+	if p == nil {
+		t.Fatal(`Import("") returned nil package.`)
+	}
+	if p.ImportPath != "" {
+		t.Fatalf("ImportPath=%q, want %q.", p.ImportPath, "")
+	}
+}
+
+func TestEmptyFolderImport(t *testing.T) {
+	_, err := Import(".", "testdata/empty", 0)
+	if _, ok := err.(*NoGoError); !ok {
+		t.Fatal(`Import("testdata/empty") did not return NoGoError.`)
+	}
+}
+
+func TestMultiplePackageImport(t *testing.T) {
+	_, err := Import(".", "testdata/multi", 0)
+	mpe, ok := err.(*MultiplePackageError)
+	if !ok {
+		t.Fatal(`Import("testdata/multi") did not return MultiplePackageError.`)
+	}
+	want := &MultiplePackageError{
+		Dir:      filepath.FromSlash("testdata/multi"),
+		Packages: []string{"main", "test_package"},
+		Files:    []string{"file.go", "file_appengine.go"},
+	}
+	if !reflect.DeepEqual(mpe, want) {
+		t.Errorf("got %#v; want %#v", mpe, want)
+	}
+}
+
+func TestLocalDirectory(t *testing.T) {
+	return // go1.3 not happy with this test.
+	if runtime.GOOS == "darwin" {
+		switch runtime.GOARCH {
+		case "arm", "arm64":
+			t.Skipf("skipping on %s/%s, no valid GOROOT", runtime.GOOS, runtime.GOARCH)
+		}
+	}
+
+	cwd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	p, err := ImportDir(cwd, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if p.ImportPath != "k8s.io/kubernetes/third_party/golang/go/build" {
+		t.Fatalf("ImportPath=%q, want %q", p.ImportPath, "k8s.io/kubernetes/third_party/golang/go/build")
+	}
+}
+
+func TestShouldBuild(t *testing.T) {
+	const file1 = "// +build tag1\n\n" +
+		"package main\n"
+	want1 := map[string]bool{"tag1": true}
+
+	const file2 = "// +build cgo\n\n" +
+		"// This package implements parsing of tags like\n" +
+		"// +build tag1\n" +
+		"package build"
+	want2 := map[string]bool{"cgo": true}
+
+	const file3 = "// Copyright The Go Authors.\n\n" +
+		"package build\n\n" +
+		"// shouldBuild checks tags given by lines of the form\n" +
+		"// +build tag\n" +
+		"func shouldBuild(content []byte)\n"
+	want3 := map[string]bool{}
+
+	ctx := &Context{BuildTags: []string{"tag1"}}
+	m := map[string]bool{}
+	if !ctx.shouldBuild([]byte(file1), m) {
+		t.Errorf("shouldBuild(file1) = false, want true")
+	}
+	if !reflect.DeepEqual(m, want1) {
+		t.Errorf("shoudBuild(file1) tags = %v, want %v", m, want1)
+	}
+
+	m = map[string]bool{}
+	if ctx.shouldBuild([]byte(file2), m) {
+		t.Errorf("shouldBuild(file2) = true, want fakse")
+	}
+	if !reflect.DeepEqual(m, want2) {
+		t.Errorf("shoudBuild(file2) tags = %v, want %v", m, want2)
+	}
+
+	m = map[string]bool{}
+	ctx = &Context{BuildTags: nil}
+	if !ctx.shouldBuild([]byte(file3), m) {
+		t.Errorf("shouldBuild(file3) = false, want true")
+	}
+	if !reflect.DeepEqual(m, want3) {
+		t.Errorf("shoudBuild(file3) tags = %v, want %v", m, want3)
+	}
+}
+
+type readNopCloser struct {
+	io.Reader
+}
+
+func (r readNopCloser) Close() error {
+	return nil
+}
+
+var (
+	ctxtP9      = Context{GOARCH: "arm", GOOS: "plan9"}
+	ctxtAndroid = Context{GOARCH: "arm", GOOS: "android"}
+)
+
+var matchFileTests = []struct {
+	ctxt  Context
+	name  string
+	data  string
+	match bool
+}{
+	{ctxtP9, "foo_arm.go", "", true},
+	{ctxtP9, "foo1_arm.go", "// +build linux\n\npackage main\n", false},
+	{ctxtP9, "foo_darwin.go", "", false},
+	{ctxtP9, "foo.go", "", true},
+	{ctxtP9, "foo1.go", "// +build linux\n\npackage main\n", false},
+	{ctxtP9, "foo.badsuffix", "", false},
+	{ctxtAndroid, "foo_linux.go", "", true},
+	{ctxtAndroid, "foo_android.go", "", true},
+	{ctxtAndroid, "foo_plan9.go", "", false},
+	{ctxtAndroid, "android.go", "", true},
+	{ctxtAndroid, "plan9.go", "", true},
+	{ctxtAndroid, "plan9_test.go", "", true},
+	{ctxtAndroid, "arm.s", "", true},
+	{ctxtAndroid, "amd64.s", "", true},
+}
+
+func TestMatchFile(t *testing.T) {
+	for _, tt := range matchFileTests {
+		ctxt := tt.ctxt
+		ctxt.OpenFile = func(path string) (r io.ReadCloser, err error) {
+			if path != "x+"+tt.name {
+				t.Fatalf("OpenFile asked for %q, expected %q", path, "x+"+tt.name)
+			}
+			return &readNopCloser{strings.NewReader(tt.data)}, nil
+		}
+		ctxt.JoinPath = func(elem ...string) string {
+			return strings.Join(elem, "+")
+		}
+		match, err := ctxt.MatchFile("x", tt.name)
+		if match != tt.match || err != nil {
+			t.Fatalf("MatchFile(%q) = %v, %v, want %v, nil", tt.name, match, err, tt.match)
+		}
+	}
+}
+
+func TestImportCmd(t *testing.T) {
+	return // go1.3 not happy with this test
+	if runtime.GOOS == "darwin" {
+		switch runtime.GOARCH {
+		case "arm", "arm64":
+			t.Skipf("skipping on %s/%s, no valid GOROOT", runtime.GOOS, runtime.GOARCH)
+		}
+	}
+
+	p, err := Import("cmd/internal/objfile", "", 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.HasSuffix(filepath.ToSlash(p.Dir), "src/cmd/internal/objfile") {
+		t.Fatalf("Import cmd/internal/objfile returned Dir=%q, want %q", filepath.ToSlash(p.Dir), ".../src/cmd/internal/objfile")
+	}
+}
+
+var (
+	expandSrcDirPath = filepath.Join(string(filepath.Separator)+"projects", "src", "add")
+)
+
+var expandSrcDirTests = []struct {
+	input, expected string
+}{
+	{"-L ${SRCDIR}/libs -ladd", "-L /projects/src/add/libs -ladd"},
+	{"${SRCDIR}/add_linux_386.a -pthread -lstdc++", "/projects/src/add/add_linux_386.a -pthread -lstdc++"},
+	{"Nothing to expand here!", "Nothing to expand here!"},
+	{"$", "$"},
+	{"$$", "$$"},
+	{"${", "${"},
+	{"$}", "$}"},
+	{"$FOO ${BAR}", "$FOO ${BAR}"},
+	{"Find me the $SRCDIRECTORY.", "Find me the $SRCDIRECTORY."},
+	{"$SRCDIR is missing braces", "$SRCDIR is missing braces"},
+}
+
+func TestExpandSrcDir(t *testing.T) {
+	for _, test := range expandSrcDirTests {
+		output := expandSrcDir(test.input, expandSrcDirPath)
+		if output != test.expected {
+			t.Errorf("%q expands to %q with SRCDIR=%q when %q is expected", test.input, output, expandSrcDirPath, test.expected)
+		} else {
+			t.Logf("%q expands to %q with SRCDIR=%q", test.input, output, expandSrcDirPath)
+		}
+	}
+}

third_party/golang/go/build/doc.go

+// Copyright 2011 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 build gathers information about Go packages.
+//
+// Go Path
+//
+// The Go path is a list of directory trees containing Go source code.
+// It is consulted to resolve imports that cannot be found in the standard
+// Go tree.  The default path is the value of the GOPATH environment
+// variable, interpreted as a path list appropriate to the operating system
+// (on Unix, the variable is a colon-separated string;
+// on Windows, a semicolon-separated string;
+// on Plan 9, a list).
+//
+// Each directory listed in the Go path must have a prescribed structure:
+//
+// The src/ directory holds source code.  The path below 'src' determines
+// the import path or executable name.
+//
+// The pkg/ directory holds installed package objects.
+// As in the Go tree, each target operating system and
+// architecture pair has its own subdirectory of pkg
+// (pkg/GOOS_GOARCH).
+//
+// If DIR is a directory listed in the Go path, a package with
+// source in DIR/src/foo/bar can be imported as "foo/bar" and
+// has its compiled form installed to "DIR/pkg/GOOS_GOARCH/foo/bar.a"
+// (or, for gccgo, "DIR/pkg/gccgo/foo/libbar.a").
+//
+// The bin/ directory holds compiled commands.
+// Each command is named for its source directory, but only
+// using the final element, not the entire path.  That is, the
+// command with source in DIR/src/foo/quux is installed into
+// DIR/bin/quux, not DIR/bin/foo/quux.  The foo/ is stripped
+// so that you can add DIR/bin to your PATH to get at the
+// installed commands.
+//
+// Here's an example directory layout:
+//
+//	GOPATH=/home/user/gocode
+//
+//	/home/user/gocode/
+//	    src/
+//	        foo/
+//	            bar/               (go code in package bar)
+//	                x.go
+//	            quux/              (go code in package main)
+//	                y.go
+//	    bin/
+//	        quux                   (installed command)
+//	    pkg/
+//	        linux_amd64/
+//	            foo/
+//	                bar.a          (installed package object)
+//
+// Build Constraints
+//
+// A build constraint, also known as a build tag, is a line comment that begins
+//
+//	// +build
+//
+// that lists the conditions under which a file should be included in the package.
+// Constraints may appear in any kind of source file (not just Go), but
+// they must appear near the top of the file, preceded
+// only by blank lines and other line comments. These rules mean that in Go
+// files a build constraint must appear before the package clause.
+//
+// To distinguish build constraints from package documentation, a series of
+// build constraints must be followed by a blank line.
+//
+// A build constraint is evaluated as the OR of space-separated options;
+// each option evaluates as the AND of its comma-separated terms;
+// and each term is an alphanumeric word or, preceded by !, its negation.
+// That is, the build constraint:
+//
+//	// +build linux,386 darwin,!cgo
+//
+// corresponds to the boolean formula:
+//
+//	(linux AND 386) OR (darwin AND (NOT cgo))
+//
+// A file may have multiple build constraints. The overall constraint is the AND
+// of the individual constraints. That is, the build constraints:
+//
+//	// +build linux darwin
+//	// +build 386
+//
+// corresponds to the boolean formula:
+//
+//	(linux OR darwin) AND 386
+//
+// During a particular build, the following words are satisfied:
+//
+//	- the target operating system, as spelled by runtime.GOOS
+//	- the target architecture, as spelled by runtime.GOARCH
+//	- the compiler being used, either "gc" or "gccgo"
+//	- "cgo", if ctxt.CgoEnabled is true
+//	- "go1.1", from Go version 1.1 onward
+//	- "go1.2", from Go version 1.2 onward
+//	- "go1.3", from Go version 1.3 onward
+//	- "go1.4", from Go version 1.4 onward
+//	- "go1.5", from Go version 1.5 onward
+//	- any additional words listed in ctxt.BuildTags
+//
+// If a file's name, after stripping the extension and a possible _test suffix,
+// matches any of the following patterns:
+//	*_GOOS
+// 	*_GOARCH
+// 	*_GOOS_GOARCH
+// (example: source_windows_amd64.go) where GOOS and GOARCH represent
+// any known operating system and architecture values respectively, then
+// the file is considered to have an implicit build constraint requiring
+// those terms (in addition to any explicit constraints in the file).
+//
+// To keep a file from being considered for the build:
+//
+//	// +build ignore
+//
+// (any other unsatisfied word will work as well, but ``ignore'' is conventional.)
+//
+// To build a file only when using cgo, and only on Linux and OS X:
+//
+//	// +build linux,cgo darwin,cgo
+//
+// Such a file is usually paired with another file implementing the
+// default functionality for other systems, which in this case would
+// carry the constraint:
+//
+//	// +build !linux,!darwin !cgo
+//
+// Naming a file dns_windows.go will cause it to be included only when
+// building the package for Windows; similarly, math_386.s will be included
+// only when building the package for 32-bit x86.
+//
+// Using GOOS=android matches build tags and files as for GOOS=linux
+// in addition to android tags and files.
+//
+package build

third_party/golang/go/build/read.go

+// Copyright 2012 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 build
+
+import (
+	"bufio"
+	"errors"
+	"io"
+)
+
+type importReader struct {
+	b    *bufio.Reader
+	buf  []byte
+	peek byte
+	err  error
+	eof  bool
+	nerr int
+}
+
+func isIdent(c byte) bool {
+	return 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z' || '0' <= c && c <= '9' || c == '_' || c >= 0x80
+}
+
+var (
+	errSyntax = errors.New("syntax error")
+	errNUL    = errors.New("unexpected NUL in input")
+)
+
+// syntaxError records a syntax error, but only if an I/O error has not already been recorded.
+func (r *importReader) syntaxError() {
+	if r.err == nil {
+		r.err = errSyntax
+	}
+}
+
+// readByte reads the next byte from the input, saves it in buf, and returns it.
+// If an error occurs, readByte records the error in r.err and returns 0.
+func (r *importReader) readByte() byte {
+	c, err := r.b.ReadByte()
+	if err == nil {
+		r.buf = append(r.buf, c)
+		if c == 0 {
+			err = errNUL
+		}
+	}
+	if err != nil {
+		if err == io.EOF {
+			r.eof = true
+		} else if r.err == nil {
+			r.err = err
+		}
+		c = 0
+	}
+	return c
+}
+
+// peekByte returns the next byte from the input reader but does not advance beyond it.
+// If skipSpace is set, peekByte skips leading spaces and comments.
+func (r *importReader) peekByte(skipSpace bool) byte {
+	if r.err != nil {
+		if r.nerr++; r.nerr > 10000 {
+			panic("go/build: import reader looping")
+		}
+		return 0
+	}
+
+	// Use r.peek as first input byte.
+	// Don't just return r.peek here: it might have been left by peekByte(false)
+	// and this might be peekByte(true).
+	c := r.peek
+	if c == 0 {
+		c = r.readByte()
+	}
+	for r.err == nil && !r.eof {
+		if skipSpace {
+			// For the purposes of this reader, semicolons are never necessary to
+			// understand the input and are treated as spaces.
+			switch c {
+			case ' ', '\f', '\t', '\r', '\n', ';':
+				c = r.readByte()
+				continue
+
+			case '/':
+				c = r.readByte()
+				if c == '/' {
+					for c != '\n' && r.err == nil && !r.eof {
+						c = r.readByte()
+					}
+				} else if c == '*' {
+					var c1 byte
+					for (c != '*' || c1 != '/') && r.err == nil {
+						if r.eof {
+							r.syntaxError()
+						}
+						c, c1 = c1, r.readByte()
+					}
+				} else {
+					r.syntaxError()
+				}
+				c = r.readByte()
+				continue
+			}
+		}
+		break
+	}
+	r.peek = c
+	return r.peek
+}
+
+// nextByte is like peekByte but advances beyond the returned byte.
+func (r *importReader) nextByte(skipSpace bool) byte {
+	c := r.peekByte(skipSpace)
+	r.peek = 0
+	return c
+}
+
+// readKeyword reads the given keyword from the input.
+// If the keyword is not present, readKeyword records a syntax error.
+func (r *importReader) readKeyword(kw string) {
+	r.peekByte(true)
+	for i := 0; i < len(kw); i++ {
+		if r.nextByte(false) != kw[i] {
+			r.syntaxError()
+			return
+		}
+	}
+	if isIdent(r.peekByte(false)) {
+		r.syntaxError()
+	}
+}
+
+// readIdent reads an identifier from the input.
+// If an identifier is not present, readIdent records a syntax error.
+func (r *importReader) readIdent() {
+	c := r.peekByte(true)
+	if !isIdent(c) {
+		r.syntaxError()
+		return
+	}
+	for isIdent(r.peekByte(false)) {
+		r.peek = 0
+	}
+}
+
+// readString reads a quoted string literal from the input.
+// If an identifier is not present, readString records a syntax error.
+func (r *importReader) readString(save *[]string) {
+	switch r.nextByte(true) {
+	case '`':
+		start := len(r.buf) - 1
+		for r.err == nil {
+			if r.nextByte(false) == '`' {
+				if save != nil {
+					*save = append(*save, string(r.buf[start:]))
+				}
+				break
+			}
+			if r.eof {
+				r.syntaxError()
+			}
+		}
+	case '"':
+		start := len(r.buf) - 1
+		for r.err == nil {
+			c := r.nextByte(false)
+			if c == '"' {
+				if save != nil {
+					*save = append(*save, string(r.buf[start:]))
+				}
+				break
+			}
+			if r.eof || c == '\n' {
+				r.syntaxError()
+			}
+			if c == '\\' {
+				r.nextByte(false)
+			}
+		}
+	default:
+		r.syntaxError()
+	}
+}
+
+// readImport reads an import clause - optional identifier followed by quoted string -
+// from the input.
+func (r *importReader) readImport(imports *[]string) {
+	c := r.peekByte(true)
+	if c == '.' {
+		r.peek = 0
+	} else if isIdent(c) {
+		r.readIdent()
+	}
+	r.readString(imports)
+}
+
+// readComments is like ioutil.ReadAll, except that it only reads the leading
+// block of comments in the file.
+func readComments(f io.Reader) ([]byte, error) {
+	r := &importReader{b: bufio.NewReader(f)}
+	r.peekByte(true)
+	if r.err == nil && !r.eof {
+		// Didn't reach EOF, so must have found a non-space byte. Remove it.
+		r.buf = r.buf[:len(r.buf)-1]
+	}
+	return r.buf, r.err
+}
+
+// readImports is like ioutil.ReadAll, except that it expects a Go file as input
+// and stops reading the input once the imports have completed.
+func readImports(f io.Reader, reportSyntaxError bool, imports *[]string) ([]byte, error) {
+	r := &importReader{b: bufio.NewReader(f)}
+
+	r.readKeyword("package")
+	r.readIdent()
+	for r.peekByte(true) == 'i' {
+		r.readKeyword("import")
+		if r.peekByte(true) == '(' {
+			r.nextByte(false)
+			for r.peekByte(true) != ')' && r.err == nil {
+				r.readImport(imports)
+			}
+			r.nextByte(false)
+		} else {
+			r.readImport(imports)
+		}
+	}
+
+	// If we stopped successfully before EOF, we read a byte that told us we were done.
+	// Return all but that last byte, which would cause a syntax error if we let it through.
+	if r.err == nil && !r.eof {
+		return r.buf[:len(r.buf)-1], nil
+	}
+
+	// If we stopped for a syntax error, consume the whole file so that
+	// we are sure we don't change the errors that go/parser returns.
+	if r.err == errSyntax && !reportSyntaxError {
+		r.err = nil
+		for r.err == nil && !r.eof {
+			r.readByte()
+		}
+	}
+
+	return r.buf, r.err
+}

third_party/golang/go/build/read_test.go

+// Copyright 2012 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 build
+
+import (
+	"io"
+	"strings"
+	"testing"
+)
+
+const quote = "`"
+
+type readTest struct {
+	// Test input contains ℙ where readImports should stop.
+	in  string
+	err string
+}
+
+var readImportsTests = []readTest{
+	{
+		`package p`,
+		"",
+	},
+	{
+		`package p; import "x"`,
+		"",
+	},
+	{
+		`package p; import . "x"`,
+		"",
+	},
+	{
+		`package p; import "x";ℙvar x = 1`,
+		"",
+	},
+	{
+		`package p
+		
+		// comment
+		
+		import "x"
+		import _ "x"
+		import a "x"
+		
+		/* comment */
+		
+		import (
+			"x" /* comment */
+			_ "x"
+			a "x" // comment
+			` + quote + `x` + quote + `
+			_ /*comment*/ ` + quote + `x` + quote + `
+			a ` + quote + `x` + quote + `
+		)
+		import (
+		)
+		import ()
+		import()import()import()
+		import();import();import()
+		
+		ℙvar x = 1
+		`,
+		"",
+	},
+}
+
+var readCommentsTests = []readTest{
+	{
+		`ℙpackage p`,
+		"",
+	},
+	{
+		`ℙpackage p; import "x"`,
+		"",
+	},
+	{
+		`ℙpackage p; import . "x"`,
+		"",
+	},
+	{
+		`// foo
+
+		/* bar */
+
+		/* quux */ // baz
+		
+		/*/ zot */
+
+		// asdf
+		ℙHello, world`,
+		"",
+	},
+}
+
+func testRead(t *testing.T, tests []readTest, read func(io.Reader) ([]byte, error)) {
+	for i, tt := range tests {
+		var in, testOut string
+		j := strings.Index(tt.in, "ℙ")
+		if j < 0 {
+			in = tt.in
+			testOut = tt.in
+		} else {
+			in = tt.in[:j] + tt.in[j+len("ℙ"):]
+			testOut = tt.in[:j]
+		}
+		r := strings.NewReader(in)
+		buf, err := read(r)
+		if err != nil {
+			if tt.err == "" {
+				t.Errorf("#%d: err=%q, expected success (%q)", i, err, string(buf))
+				continue
+			}
+			if !strings.Contains(err.Error(), tt.err) {
+				t.Errorf("#%d: err=%q, expected %q", i, err, tt.err)
+				continue
+			}
+			continue
+		}
+		if err == nil && tt.err != "" {
+			t.Errorf("#%d: success, expected %q", i, tt.err)
+			continue
+		}
+
+		out := string(buf)
+		if out != testOut {
+			t.Errorf("#%d: wrong output:\nhave %q\nwant %q\n", i, out, testOut)
+		}
+	}
+}
+
+func TestReadImports(t *testing.T) {
+	testRead(t, readImportsTests, func(r io.Reader) ([]byte, error) { return readImports(r, true, nil) })
+}
+
+func TestReadComments(t *testing.T) {
+	testRead(t, readCommentsTests, readComments)
+}
+
+var readFailuresTests = []readTest{
+	{
+		`package`,
+		"syntax error",
+	},
+	{
+		"package p\n\x00\nimport `math`\n",
+		"unexpected NUL in input",
+	},
+	{
+		`package p; import`,
+		"syntax error",
+	},
+	{
+		`package p; import "`,
+		"syntax error",
+	},
+	{
+		"package p; import ` \n\n",
+		"syntax error",
+	},
+	{
+		`package p; import "x`,
+		"syntax error",
+	},
+	{
+		`package p; import _`,
+		"syntax error",
+	},
+	{
+		`package p; import _ "`,
+		"syntax error",
+	},
+	{
+		`package p; import _ "x`,
+		"syntax error",
+	},
+	{
+		`package p; import .`,
+		"syntax error",
+	},
+	{
+		`package p; import . "`,
+		"syntax error",
+	},
+	{
+		`package p; import . "x`,
+		"syntax error",
+	},
+	{
+		`package p; import (`,
+		"syntax error",
+	},
+	{
+		`package p; import ("`,
+		"syntax error",
+	},
+	{
+		`package p; import ("x`,
+		"syntax error",
+	},
+	{
+		`package p; import ("x"`,
+		"syntax error",
+	},
+}
+
+func TestReadFailures(t *testing.T) {
+	// Errors should be reported (true arg to readImports).
+	testRead(t, readFailuresTests, func(r io.Reader) ([]byte, error) { return readImports(r, true, nil) })
+}
+
+func TestReadFailuresIgnored(t *testing.T) {
+	// Syntax errors should not be reported (false arg to readImports).
+	// Instead, entire file should be the output and no error.
+	// Convert tests not to return syntax errors.
+	tests := make([]readTest, len(readFailuresTests))
+	copy(tests, readFailuresTests)
+	for i := range tests {
+		tt := &tests[i]
+		if !strings.Contains(tt.err, "NUL") {
+			tt.err = ""
+		}
+	}
+	testRead(t, tests, func(r io.Reader) ([]byte, error) { return readImports(r, false, nil) })
+}