Vendor goimports by adding it to tools.go

go.mod

@@ -120,7 +120,7 @@ require (
 	golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529
 	golang.org/x/net v0.0.0-20190812203447-cdfb69ac37fc
 	golang.org/x/oauth2 v0.0.0-20190402181905-9f3314589c9a
-	golang.org/x/tools v0.0.0-20191124021906-f5828fc9a103 // indirect
+	golang.org/x/tools v0.0.0-20191124021906-f5828fc9a103
 	google.golang.org/api v0.0.0-20181220000619-583d854617af
 	gopkg.in/gcfg.v1 v1.2.0
 	gopkg.in/inf.v0 v0.9.1

tools.go

@@ -26,6 +26,8 @@ import (
 
 	_ "github.com/client9/misspell/cmd/misspell"
 
+	_ "golang.org/x/tools/cmd/goimports"
+
 	_ "honnef.co/go/tools/cmd/staticcheck"
 
 	_ "sigs.k8s.io/controller-tools/cmd/controller-gen"

vendor/golang.org/x/tools/cmd/goimports/BUILD.bazel

@@ -0,0 +1,20 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "doc.go",
+        "goimports.go",
+        "goimports_gc.go",
+    ],
+    importmap = "k8s.io/kops/vendor/golang.org/x/tools/cmd/goimports",
+    importpath = "golang.org/x/tools/cmd/goimports",
+    visibility = ["//visibility:private"],
+    deps = ["//vendor/golang.org/x/tools/internal/imports:go_default_library"],
+)
+
+go_binary(
+    name = "goimports",
+    embed = [":go_default_library"],
+    visibility = ["//visibility:public"],
+)

vendor/golang.org/x/tools/cmd/goimports/doc.go

@@ -0,0 +1,43 @@
+/*
+
+Command goimports updates your Go import lines,
+adding missing ones and removing unreferenced ones.
+
+     $ go get golang.org/x/tools/cmd/goimports
+
+In addition to fixing imports, goimports also formats
+your code in the same style as gofmt so it can be used
+as a replacement for your editor's gofmt-on-save hook.
+
+For emacs, make sure you have the latest go-mode.el:
+   https://github.com/dominikh/go-mode.el
+Then in your .emacs file:
+   (setq gofmt-command "goimports")
+   (add-hook 'before-save-hook 'gofmt-before-save)
+
+For vim, set "gofmt_command" to "goimports":
+    https://golang.org/change/39c724dd7f252
+    https://golang.org/wiki/IDEsAndTextEditorPlugins
+    etc
+
+For GoSublime, follow the steps described here:
+    http://michaelwhatcott.com/gosublime-goimports/
+
+For other editors, you probably know what to do.
+
+To exclude directories in your $GOPATH from being scanned for Go
+files, goimports respects a configuration file at
+$GOPATH/src/.goimportsignore which may contain blank lines, comment
+lines (beginning with '#'), or lines naming a directory relative to
+the configuration file to ignore when scanning. No globbing or regex
+patterns are allowed. Use the "-v" verbose flag to verify it's
+working and see what goimports is doing.
+
+File bugs or feature requests at:
+
+    https://golang.org/issues/new?title=x/tools/cmd/goimports:+
+
+Happy hacking!
+
+*/
+package main // import "golang.org/x/tools/cmd/goimports"

vendor/golang.org/x/tools/cmd/goimports/goimports.go

@@ -0,0 +1,377 @@
+// 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.
+
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"flag"
+	"fmt"
+	"go/build"
+	"go/scanner"
+	"io"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"runtime/pprof"
+	"strings"
+
+	"golang.org/x/tools/internal/imports"
+)
+
+var (
+	// main operation modes
+	list   = flag.Bool("l", false, "list files whose formatting differs from goimport's")
+	write  = flag.Bool("w", false, "write result to (source) file instead of stdout")
+	doDiff = flag.Bool("d", false, "display diffs instead of rewriting files")
+	srcdir = flag.String("srcdir", "", "choose imports as if source code is from `dir`. When operating on a single file, dir may instead be the complete file name.")
+
+	verbose bool // verbose logging
+
+	cpuProfile     = flag.String("cpuprofile", "", "CPU profile output")
+	memProfile     = flag.String("memprofile", "", "memory profile output")
+	memProfileRate = flag.Int("memrate", 0, "if > 0, sets runtime.MemProfileRate")
+
+	options = &imports.Options{
+		TabWidth:  8,
+		TabIndent: true,
+		Comments:  true,
+		Fragment:  true,
+		// This environment, and its caches, will be reused for the whole run.
+		Env: &imports.ProcessEnv{
+			GOPATH: build.Default.GOPATH,
+			GOROOT: build.Default.GOROOT,
+		},
+	}
+	exitCode = 0
+)
+
+func init() {
+	flag.BoolVar(&options.AllErrors, "e", false, "report all errors (not just the first 10 on different lines)")
+	flag.StringVar(&options.Env.LocalPrefix, "local", "", "put imports beginning with this string after 3rd-party packages; comma-separated list")
+	flag.BoolVar(&options.FormatOnly, "format-only", false, "if true, don't fix imports and only format. In this mode, goimports is effectively gofmt, with the addition that imports are grouped into sections.")
+}
+
+func report(err error) {
+	scanner.PrintError(os.Stderr, err)
+	exitCode = 2
+}
+
+func usage() {
+	fmt.Fprintf(os.Stderr, "usage: goimports [flags] [path ...]\n")
+	flag.PrintDefaults()
+	os.Exit(2)
+}
+
+func isGoFile(f os.FileInfo) bool {
+	// ignore non-Go files
+	name := f.Name()
+	return !f.IsDir() && !strings.HasPrefix(name, ".") && strings.HasSuffix(name, ".go")
+}
+
+// argumentType is which mode goimports was invoked as.
+type argumentType int
+
+const (
+	// fromStdin means the user is piping their source into goimports.
+	fromStdin argumentType = iota
+
+	// singleArg is the common case from editors, when goimports is run on
+	// a single file.
+	singleArg
+
+	// multipleArg is when the user ran "goimports file1.go file2.go"
+	// or ran goimports on a directory tree.
+	multipleArg
+)
+
+func processFile(filename string, in io.Reader, out io.Writer, argType argumentType) error {
+	opt := options
+	if argType == fromStdin {
+		nopt := *options
+		nopt.Fragment = true
+		opt = &nopt
+	}
+
+	if in == nil {
+		f, err := os.Open(filename)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		in = f
+	}
+
+	src, err := ioutil.ReadAll(in)
+	if err != nil {
+		return err
+	}
+
+	target := filename
+	if *srcdir != "" {
+		// Determine whether the provided -srcdirc is a directory or file
+		// and then use it to override the target.
+		//
+		// See https://github.com/dominikh/go-mode.el/issues/146
+		if isFile(*srcdir) {
+			if argType == multipleArg {
+				return errors.New("-srcdir value can't be a file when passing multiple arguments or when walking directories")
+			}
+			target = *srcdir
+		} else if argType == singleArg && strings.HasSuffix(*srcdir, ".go") && !isDir(*srcdir) {
+			// For a file which doesn't exist on disk yet, but might shortly.
+			// e.g. user in editor opens $DIR/newfile.go and newfile.go doesn't yet exist on disk.
+			// The goimports on-save hook writes the buffer to a temp file
+			// first and runs goimports before the actual save to newfile.go.
+			// The editor's buffer is named "newfile.go" so that is passed to goimports as:
+			//      goimports -srcdir=/gopath/src/pkg/newfile.go /tmp/gofmtXXXXXXXX.go
+			// and then the editor reloads the result from the tmp file and writes
+			// it to newfile.go.
+			target = *srcdir
+		} else {
+			// Pretend that file is from *srcdir in order to decide
+			// visible imports correctly.
+			target = filepath.Join(*srcdir, filepath.Base(filename))
+		}
+	}
+
+	res, err := imports.Process(target, src, opt)
+	if err != nil {
+		return err
+	}
+
+	if !bytes.Equal(src, res) {
+		// formatting has changed
+		if *list {
+			fmt.Fprintln(out, filename)
+		}
+		if *write {
+			if argType == fromStdin {
+				// filename is "<standard input>"
+				return errors.New("can't use -w on stdin")
+			}
+			err = ioutil.WriteFile(filename, res, 0)
+			if err != nil {
+				return err
+			}
+		}
+		if *doDiff {
+			if argType == fromStdin {
+				filename = "stdin.go" // because <standard input>.orig looks silly
+			}
+			data, err := diff(src, res, filename)
+			if err != nil {
+				return fmt.Errorf("computing diff: %s", err)
+			}
+			fmt.Printf("diff -u %s %s\n", filepath.ToSlash(filename+".orig"), filepath.ToSlash(filename))
+			out.Write(data)
+		}
+	}
+
+	if !*list && !*write && !*doDiff {
+		_, err = out.Write(res)
+	}
+
+	return err
+}
+
+func visitFile(path string, f os.FileInfo, err error) error {
+	if err == nil && isGoFile(f) {
+		err = processFile(path, nil, os.Stdout, multipleArg)
+	}
+	if err != nil {
+		report(err)
+	}
+	return nil
+}
+
+func walkDir(path string) {
+	filepath.Walk(path, visitFile)
+}
+
+func main() {
+	runtime.GOMAXPROCS(runtime.NumCPU())
+
+	// call gofmtMain in a separate function
+	// so that it can use defer and have them
+	// run before the exit.
+	gofmtMain()
+	os.Exit(exitCode)
+}
+
+// parseFlags parses command line flags and returns the paths to process.
+// It's a var so that custom implementations can replace it in other files.
+var parseFlags = func() []string {
+	flag.BoolVar(&verbose, "v", false, "verbose logging")
+
+	flag.Parse()
+	return flag.Args()
+}
+
+func bufferedFileWriter(dest string) (w io.Writer, close func()) {
+	f, err := os.Create(dest)
+	if err != nil {
+		log.Fatal(err)
+	}
+	bw := bufio.NewWriter(f)
+	return bw, func() {
+		if err := bw.Flush(); err != nil {
+			log.Fatalf("error flushing %v: %v", dest, err)
+		}
+		if err := f.Close(); err != nil {
+			log.Fatal(err)
+		}
+	}
+}
+
+func gofmtMain() {
+	flag.Usage = usage
+	paths := parseFlags()
+
+	if *cpuProfile != "" {
+		bw, flush := bufferedFileWriter(*cpuProfile)
+		pprof.StartCPUProfile(bw)
+		defer flush()
+		defer pprof.StopCPUProfile()
+	}
+	// doTrace is a conditionally compiled wrapper around runtime/trace. It is
+	// used to allow goimports to compile under gccgo, which does not support
+	// runtime/trace. See https://golang.org/issue/15544.
+	defer doTrace()()
+	if *memProfileRate > 0 {
+		runtime.MemProfileRate = *memProfileRate
+		bw, flush := bufferedFileWriter(*memProfile)
+		defer func() {
+			runtime.GC() // materialize all statistics
+			if err := pprof.WriteHeapProfile(bw); err != nil {
+				log.Fatal(err)
+			}
+			flush()
+		}()
+	}
+
+	if verbose {
+		log.SetFlags(log.LstdFlags | log.Lmicroseconds)
+		options.Env.Debug = true
+	}
+	if options.TabWidth < 0 {
+		fmt.Fprintf(os.Stderr, "negative tabwidth %d\n", options.TabWidth)
+		exitCode = 2
+		return
+	}
+
+	if len(paths) == 0 {
+		if err := processFile("<standard input>", os.Stdin, os.Stdout, fromStdin); err != nil {
+			report(err)
+		}
+		return
+	}
+
+	argType := singleArg
+	if len(paths) > 1 {
+		argType = multipleArg
+	}
+
+	for _, path := range paths {
+		switch dir, err := os.Stat(path); {
+		case err != nil:
+			report(err)
+		case dir.IsDir():
+			walkDir(path)
+		default:
+			if err := processFile(path, nil, os.Stdout, argType); err != nil {
+				report(err)
+			}
+		}
+	}
+}
+
+func writeTempFile(dir, prefix string, data []byte) (string, error) {
+	file, err := ioutil.TempFile(dir, prefix)
+	if err != nil {
+		return "", err
+	}
+	_, err = file.Write(data)
+	if err1 := file.Close(); err == nil {
+		err = err1
+	}
+	if err != nil {
+		os.Remove(file.Name())
+		return "", err
+	}
+	return file.Name(), nil
+}
+
+func diff(b1, b2 []byte, filename string) (data []byte, err error) {
+	f1, err := writeTempFile("", "gofmt", b1)
+	if err != nil {
+		return
+	}
+	defer os.Remove(f1)
+
+	f2, err := writeTempFile("", "gofmt", b2)
+	if err != nil {
+		return
+	}
+	defer os.Remove(f2)
+
+	cmd := "diff"
+	if runtime.GOOS == "plan9" {
+		cmd = "/bin/ape/diff"
+	}
+
+	data, err = exec.Command(cmd, "-u", f1, f2).CombinedOutput()
+	if len(data) > 0 {
+		// diff exits with a non-zero status when the files don't match.
+		// Ignore that failure as long as we get output.
+		return replaceTempFilename(data, filename)
+	}
+	return
+}
+
+// replaceTempFilename replaces temporary filenames in diff with actual one.
+//
+// --- /tmp/gofmt316145376	2017-02-03 19:13:00.280468375 -0500
+// +++ /tmp/gofmt617882815	2017-02-03 19:13:00.280468375 -0500
+// ...
+// ->
+// --- path/to/file.go.orig	2017-02-03 19:13:00.280468375 -0500
+// +++ path/to/file.go	2017-02-03 19:13:00.280468375 -0500
+// ...
+func replaceTempFilename(diff []byte, filename string) ([]byte, error) {
+	bs := bytes.SplitN(diff, []byte{'\n'}, 3)
+	if len(bs) < 3 {
+		return nil, fmt.Errorf("got unexpected diff for %s", filename)
+	}
+	// Preserve timestamps.
+	var t0, t1 []byte
+	if i := bytes.LastIndexByte(bs[0], '\t'); i != -1 {
+		t0 = bs[0][i:]
+	}
+	if i := bytes.LastIndexByte(bs[1], '\t'); i != -1 {
+		t1 = bs[1][i:]
+	}
+	// Always print filepath with slash separator.
+	f := filepath.ToSlash(filename)
+	bs[0] = []byte(fmt.Sprintf("--- %s%s", f+".orig", t0))
+	bs[1] = []byte(fmt.Sprintf("+++ %s%s", f, t1))
+	return bytes.Join(bs, []byte{'\n'}), nil
+}
+
+// isFile reports whether name is a file.
+func isFile(name string) bool {
+	fi, err := os.Stat(name)
+	return err == nil && fi.Mode().IsRegular()
+}
+
+// isDir reports whether name is a directory.
+func isDir(name string) bool {
+	fi, err := os.Stat(name)
+	return err == nil && fi.IsDir()
+}

vendor/golang.org/x/tools/cmd/goimports/goimports_gc.go

@@ -0,0 +1,26 @@
+// Copyright 2016 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.
+
+// +build gc
+
+package main
+
+import (
+	"flag"
+	"runtime/trace"
+)
+
+var traceProfile = flag.String("trace", "", "trace profile output")
+
+func doTrace() func() {
+	if *traceProfile != "" {
+		bw, flush := bufferedFileWriter(*traceProfile)
+		trace.Start(bw)
+		return func() {
+			flush()
+			trace.Stop()
+		}
+	}
+	return func() {}
+}

vendor/golang.org/x/tools/cmd/goimports/goimports_not_gc.go

@@ -0,0 +1,11 @@
+// Copyright 2016 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.
+
+// +build !gc
+
+package main
+
+func doTrace() func() {
+	return func() {}
+}

vendor/golang.org/x/tools/go/analysis/analysis.go

@@ -128,11 +128,13 @@ type Pass struct {
 	// See comments for ExportObjectFact.
 	ExportPackageFact func(fact Fact)
 
-	// AllPackageFacts returns a new slice containing all package facts in unspecified order.
+	// AllPackageFacts returns a new slice containing all package facts of the analysis's FactTypes
+	// in unspecified order.
 	// WARNING: This is an experimental API and may change in the future.
 	AllPackageFacts func() []PackageFact
 
-	// AllObjectFacts returns a new slice containing all object facts in unspecified order.
+	// AllObjectFacts returns a new slice containing all object facts of the analysis's FactTypes
+	// in unspecified order.
 	// WARNING: This is an experimental API and may change in the future.
 	AllObjectFacts func() []ObjectFact
 
@@ -161,13 +163,19 @@ func (pass *Pass) Reportf(pos token.Pos, format string, args ...interface{}) {
 	pass.Report(Diagnostic{Pos: pos, Message: msg})
 }
 
-// reportNodef is a helper function that reports a Diagnostic using the
-// range denoted by the AST node.
-//
-// WARNING: This is an experimental API and may change in the future.
-func (pass *Pass) reportNodef(node ast.Node, format string, args ...interface{}) {
+// The Range interface provides a range. It's equivalent to and satisfied by
+// ast.Node.
+type Range interface {
+	Pos() token.Pos // position of first character belonging to the node
+	End() token.Pos // position of first character immediately after the node
+}
+
+// ReportRangef is a helper function that reports a Diagnostic using the
+// range provided. ast.Node values can be passed in as the range because
+// they satisfy the Range interface.
+func (pass *Pass) ReportRangef(rng Range, format string, args ...interface{}) {
 	msg := fmt.Sprintf(format, args...)
-	pass.Report(Diagnostic{Pos: node.Pos(), End: node.End(), Message: msg})
+	pass.Report(Diagnostic{Pos: rng.Pos(), End: rng.End(), Message: msg})
 }
 
 func (pass *Pass) String() string {

vendor/golang.org/x/tools/go/analysis/diagnostic.go

@@ -1,5 +1,3 @@
-// +build !experimental
-
 package analysis
 
 import "go/token"
@@ -17,4 +15,47 @@ type Diagnostic struct {
 	End      token.Pos // optional
 	Category string    // optional
 	Message  string
+
+	// SuggestedFixes contains suggested fixes for a diagnostic which can be used to perform
+	// edits to a file that address the diagnostic.
+	// TODO(matloob): Should multiple SuggestedFixes be allowed for a diagnostic?
+	// Diagnostics should not contain SuggestedFixes that overlap.
+	// Experimental: This API is experimental and may change in the future.
+	SuggestedFixes []SuggestedFix // optional
+
+	// Experimental: This API is experimental and may change in the future.
+	Related []RelatedInformation // optional
+}
+
+// RelatedInformation contains information related to a diagnostic.
+// For example, a diagnostic that flags duplicated declarations of a
+// variable may include one RelatedInformation per existing
+// declaration.
+type RelatedInformation struct {
+	Pos     token.Pos
+	End     token.Pos
+	Message string
+}
+
+// A SuggestedFix is a code change associated with a Diagnostic that a user can choose
+// to apply to their code. Usually the SuggestedFix is meant to fix the issue flagged
+// by the diagnostic.
+// TextEdits for a SuggestedFix should not overlap. TextEdits for a SuggestedFix
+// should not contain edits for other packages.
+// Experimental: This API is experimental and may change in the future.
+type SuggestedFix struct {
+	// A description for this suggested fix to be shown to a user deciding
+	// whether to accept it.
+	Message   string
+	TextEdits []TextEdit
+}
+
+// A TextEdit represents the replacement of the code between Pos and End with the new text.
+// Each TextEdit should apply to a single file. End should not be earlier in the file than Pos.
+// Experimental: This API is experimental and may change in the future.
+type TextEdit struct {
+	// For a pure insertion, End can either be set to Pos or token.NoPos.
+	Pos     token.Pos
+	End     token.Pos
+	NewText []byte
 }

vendor/golang.org/x/tools/go/analysis/diagnostic_experimental.go

@@ -1,41 +0,0 @@
-// +build experimental
-
-package analysis
-
-import "go/token"
-
-// A Diagnostic is a message associated with a source location or range.
-//
-// An Analyzer may return a variety of diagnostics; the optional Category,
-// which should be a constant, may be used to classify them.
-// It is primarily intended to make it easy to look up documentation.
-//
-// If End is provided, the diagnostic is specified to apply to the range between
-// Pos and End.
-type Diagnostic struct {
-	Pos      token.Pos
-	End      token.Pos // optional
-	Category string    // optional
-	Message  string
-
-	// TODO(matloob): Should multiple SuggestedFixes be allowed for a diagnostic?
-	SuggestedFixes []SuggestedFix // optional
-}
-
-// A SuggestedFix is a code change associated with a Diagnostic that a user can choose
-// to apply to their code. Usually the SuggestedFix is meant to fix the issue flagged
-// by the diagnostic.
-type SuggestedFix struct {
-	// A description for this suggested fix to be shown to a user deciding
-	// whether to accept it.
-	Message   string
-	TextEdits []TextEdit
-}
-
-// A TextEdit represents the replacement of the code between Pos and End with the new text.
-type TextEdit struct {
-	// For a pure insertion, End can either be set to Pos or token.NoPos.
-	Pos     token.Pos
-	End     token.Pos
-	NewText []byte
-}

vendor/golang.org/x/tools/go/analysis/doc.go

@@ -67,7 +67,7 @@ To add a new Analyzer to an existing driver, add another item to the list:
 	}
 
 A driver may use the name, flags, and documentation to provide on-line
-help that describes the analyses its performs.
+help that describes the analyses it performs.
 The doc comment contains a brief one-line summary,
 optionally followed by paragraphs of explanation.
 The vet command, shown below, is an example of a driver that runs
@@ -169,7 +169,7 @@ type information, and source positions for a single package of Go code.
 
 The OtherFiles field provides the names, but not the contents, of non-Go
 files such as assembly that are part of this package. See the "asmdecl"
-or "buildtags" analyzers for examples of loading non-Go files and report
+or "buildtags" analyzers for examples of loading non-Go files and reporting
 diagnostics against them.
 
 The ResultOf field provides the results computed by the analyzers
@@ -231,7 +231,7 @@ understood as alternative or non-standard type systems. For example,
 vet's printf checker infers whether a function has the "printf wrapper"
 type, and it applies stricter checks to calls of such functions. In
 addition, it records which functions are printf wrappers for use by
-later analysis units to identify other printf wrappers by induction.
+later analysis passes to identify other printf wrappers by induction.
 A result such as “f is a printf wrapper” that is not interesting by
 itself but serves as a stepping stone to an interesting result (such as
 a diagnostic) is called a "fact".
@@ -252,9 +252,9 @@ An Analyzer that uses facts must declare their types:
 
 	type isWrapper struct{} // => *types.Func f “is a printf wrapper”
 
-A driver program ensures that facts for a pass’s dependencies are
-generated before analyzing the pass and are responsible for propagating
-facts between from one pass to another, possibly across address spaces.
+The driver program ensures that facts for a pass’s dependencies are
+generated before analyzing the package and is responsible for propagating
+facts from one package to another, possibly across address spaces.
 Consequently, Facts must be serializable. The API requires that drivers
 use the gob encoding, an efficient, robust, self-describing binary
 protocol. A fact type may implement the GobEncoder/GobDecoder interfaces
@@ -288,10 +288,10 @@ not currently apply analyzers to packages of the standard library.
 Therefore, for best results, analyzer authors should not rely on
 analysis facts being available for standard packages.
 For example, although the printf checker is capable of deducing during
-analysis of the log package that log.Printf is a printf-wrapper,
+analysis of the log package that log.Printf is a printf wrapper,
 this fact is built in to the analyzer so that it correctly checks
 calls to log.Printf even when run in a driver that does not apply
-it to standard packages. We plan to remove this limitation in future.
+it to standard packages. We would like to remove this limitation in future.
 
 
 Testing an Analyzer

vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go

@@ -16,7 +16,7 @@
 //
 //	var Analyzer = &analysis.Analyzer{
 //		...
-//		Requires:       reflect.TypeOf(new(inspect.Analyzer)),
+//		Requires:       []*analysis.Analyzer{inspect.Analyzer},
 //	}
 //
 // 	func run(pass *analysis.Pass) (interface{}, error) {

vendor/golang.org/x/tools/go/analysis/validate.go

@@ -9,13 +9,10 @@ import (
 // Validate reports an error if any of the analyzers are misconfigured.
 // Checks include:
 // that the name is a valid identifier;
-// that analyzer names are unique;
-// that the Requires graph is acylic;
+// that the Requires graph is acyclic;
 // that analyzer fact types are unique;
 // that each fact type is a pointer.
 func Validate(analyzers []*Analyzer) error {
-	names := make(map[string]bool)
-
 	// Map each fact type to its sole generating analyzer.
 	factTypes := make(map[reflect.Type]*Analyzer)
 
@@ -39,10 +36,6 @@ func Validate(analyzers []*Analyzer) error {
 			if !validIdent(a.Name) {
 				return fmt.Errorf("invalid analyzer name %q", a)
 			}
-			if names[a.Name] {
-				return fmt.Errorf("duplicate analyzer name %q", a)
-			}
-			names[a.Name] = true
 
 			if a.Doc == "" {
 				return fmt.Errorf("analyzer %q is undocumented", a)

vendor/golang.org/x/tools/go/buildutil/overlay.go

@@ -65,7 +65,7 @@ func OverlayContext(orig *build.Context, overlay map[string][]byte) *build.Conte
 //
 // The archive consists of a series of files. Each file consists of a
 // name, a decimal file size and the file contents, separated by
-// newlinews. No newline follows after the file contents.
+// newlines. No newline follows after the file contents.
 func ParseOverlayArchive(archive io.Reader) (map[string][]byte, error) {
 	overlay := make(map[string][]byte)
 	r := bufio.NewReader(archive)

vendor/golang.org/x/tools/go/gcexportdata/gcexportdata.go

@@ -100,7 +100,7 @@ func Read(in io.Reader, fset *token.FileSet, imports map[string]*types.Package,
 // Write writes encoded type information for the specified package to out.
 // The FileSet provides file position information for named objects.
 func Write(out io.Writer, fset *token.FileSet, pkg *types.Package) error {
-	b, err := gcimporter.BExportData(fset, pkg)
+	b, err := gcimporter.IExportData(fset, pkg)
 	if err != nil {
 		return err
 	}

vendor/golang.org/x/tools/go/internal/gcimporter/bimport.go

@@ -332,7 +332,7 @@ func (p *importer) pos() token.Pos {
 	p.prevFile = file
 	p.prevLine = line
 
-	return p.fake.pos(file, line)
+	return p.fake.pos(file, line, 0)
 }
 
 // Synthesize a token.Pos
@@ -341,7 +341,9 @@ type fakeFileSet struct {
 	files map[string]*token.File
 }
 
-func (s *fakeFileSet) pos(file string, line int) token.Pos {
+func (s *fakeFileSet) pos(file string, line, column int) token.Pos {
+	// TODO(mdempsky): Make use of column.
+
 	// Since we don't know the set of needed file positions, we
 	// reserve maxlines positions per file.
 	const maxlines = 64 * 1024
@@ -976,10 +978,11 @@ const (
 	aliasTag
 )
 
+var predeclOnce sync.Once
 var predecl []types.Type // initialized lazily
 
 func predeclared() []types.Type {
-	if predecl == nil {
+	predeclOnce.Do(func() {
 		// initialize lazily to be sure that all
 		// elements have been initialized before
 		predecl = []types.Type{ // basic types
@@ -1026,7 +1029,7 @@ func predeclared() []types.Type {
 			// used internally by gc; never used by this package or in .a files
 			anyType{},
 		}
-	}
+	})
 	return predecl
 }
 

vendor/golang.org/x/tools/go/internal/gcimporter/iexport.go

@@ -6,8 +6,6 @@
 // This file was derived from $GOROOT/src/cmd/compile/internal/gc/iexport.go;
 // see that file for specification of the format.
 
-// +build go1.11
-
 package gcimporter
 
 import (
@@ -28,7 +26,10 @@ import (
 const iexportVersion = 0
 
 // IExportData returns the binary export data for pkg.
+//
 // If no file set is provided, position info will be missing.
+// The package path of the top-level package will not be recorded,
+// so that calls to IImportData can override with a provided package path.
 func IExportData(fset *token.FileSet, pkg *types.Package) (b []byte, err error) {
 	defer func() {
 		if e := recover(); e != nil {
@@ -48,6 +49,7 @@ func IExportData(fset *token.FileSet, pkg *types.Package) (b []byte, err error)
 		stringIndex: map[string]uint64{},
 		declIndex:   map[types.Object]uint64{},
 		typIndex:    map[types.Type]uint64{},
+		localpkg:    pkg,
 	}
 
 	for i, pt := range predeclared() {
@@ -73,7 +75,7 @@ func IExportData(fset *token.FileSet, pkg *types.Package) (b []byte, err error)
 	// Append indices to data0 section.
 	dataLen := uint64(p.data0.Len())
 	w := p.newWriter()
-	w.writeIndex(p.declIndex, pkg)
+	w.writeIndex(p.declIndex)
 	w.flush()
 
 	// Assemble header.
@@ -95,14 +97,14 @@ func IExportData(fset *token.FileSet, pkg *types.Package) (b []byte, err error)
 // we're writing out the main index, which is also read by
 // non-compiler tools and includes a complete package description
 // (i.e., name and height).
-func (w *exportWriter) writeIndex(index map[types.Object]uint64, localpkg *types.Package) {
+func (w *exportWriter) writeIndex(index map[types.Object]uint64) {
 	// Build a map from packages to objects from that package.
 	pkgObjs := map[*types.Package][]types.Object{}
 
 	// For the main index, make sure to include every package that
 	// we reference, even if we're not exporting (or reexporting)
 	// any symbols from it.
-	pkgObjs[localpkg] = nil
+	pkgObjs[w.p.localpkg] = nil
 	for pkg := range w.p.allPkgs {
 		pkgObjs[pkg] = nil
 	}
@@ -121,12 +123,12 @@ func (w *exportWriter) writeIndex(index map[types.Object]uint64, localpkg *types
 	}
 
 	sort.Slice(pkgs, func(i, j int) bool {
-		return pkgs[i].Path() < pkgs[j].Path()
+		return w.exportPath(pkgs[i]) < w.exportPath(pkgs[j])
 	})
 
 	w.uint64(uint64(len(pkgs)))
 	for _, pkg := range pkgs {
-		w.string(pkg.Path())
+		w.string(w.exportPath(pkg))
 		w.string(pkg.Name())
 		w.uint64(uint64(0)) // package height is not needed for go/types
 
@@ -143,6 +145,8 @@ type iexporter struct {
 	fset *token.FileSet
 	out  *bytes.Buffer
 
+	localpkg *types.Package
+
 	// allPkgs tracks all packages that have been referenced by
 	// the export data, so we can ensure to include them in the
 	// main index.
@@ -195,6 +199,13 @@ type exportWriter struct {
 	prevLine int64
 }
 
+func (w *exportWriter) exportPath(pkg *types.Package) string {
+	if pkg == w.p.localpkg {
+		return ""
+	}
+	return pkg.Path()
+}
+
 func (p *iexporter) doDecl(obj types.Object) {
 	w := p.newWriter()
 	w.setPkg(obj.Pkg(), false)
@@ -267,6 +278,11 @@ func (w *exportWriter) tag(tag byte) {
 }
 
 func (w *exportWriter) pos(pos token.Pos) {
+	if w.p.fset == nil {
+		w.int64(0)
+		return
+	}
+
 	p := w.p.fset.Position(pos)
 	file := p.Filename
 	line := int64(p.Line)
@@ -299,7 +315,7 @@ func (w *exportWriter) pkg(pkg *types.Package) {
 	// Ensure any referenced packages are declared in the main index.
 	w.p.allPkgs[pkg] = true
 
-	w.string(pkg.Path())
+	w.string(w.exportPath(pkg))
 }
 
 func (w *exportWriter) qualifiedIdent(obj types.Object) {
@@ -394,7 +410,7 @@ func (w *exportWriter) doTyp(t types.Type, pkg *types.Package) {
 			w.pos(f.Pos())
 			w.string(f.Name())
 			w.typ(f.Type(), pkg)
-			w.bool(f.Embedded())
+			w.bool(f.Anonymous())
 			w.string(t.Tag(i)) // note (or tag)
 		}
 

vendor/golang.org/x/tools/go/internal/gcimporter/iimport.go

@@ -63,8 +63,8 @@ const (
 // If the export data version is not recognized or the format is otherwise
 // compromised, an error is returned.
 func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (_ int, pkg *types.Package, err error) {
-	const currentVersion = 0
-	version := -1
+	const currentVersion = 1
+	version := int64(-1)
 	defer func() {
 		if e := recover(); e != nil {
 			if version > currentVersion {
@@ -77,9 +77,9 @@ func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []
 
 	r := &intReader{bytes.NewReader(data), path}
 
-	version = int(r.uint64())
+	version = int64(r.uint64())
 	switch version {
-	case currentVersion:
+	case currentVersion, 0:
 	default:
 		errorf("unknown iexport format version %d", version)
 	}
@@ -93,7 +93,8 @@ func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []
 	r.Seek(sLen+dLen, io.SeekCurrent)
 
 	p := iimporter{
-		ipath: path,
+		ipath:   path,
+		version: int(version),
 
 		stringData:  stringData,
 		stringCache: make(map[uint64]string),
@@ -142,20 +143,18 @@ func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []
 		p.pkgIndex[pkg] = nameIndex
 		pkgList[i] = pkg
 	}
-	var localpkg *types.Package
-	for _, pkg := range pkgList {
-		if pkg.Path() == path {
-			localpkg = pkg
-		}
+	if len(pkgList) == 0 {
+		errorf("no packages found for %s", path)
+		panic("unreachable")
 	}
-
-	names := make([]string, 0, len(p.pkgIndex[localpkg]))
-	for name := range p.pkgIndex[localpkg] {
+	p.ipkg = pkgList[0]
+	names := make([]string, 0, len(p.pkgIndex[p.ipkg]))
+	for name := range p.pkgIndex[p.ipkg] {
 		names = append(names, name)
 	}
 	sort.Strings(names)
 	for _, name := range names {
-		p.doDecl(localpkg, name)
+		p.doDecl(p.ipkg, name)
 	}
 
 	for _, typ := range p.interfaceList {
@@ -165,17 +164,19 @@ func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []
 	// record all referenced packages as imports
 	list := append(([]*types.Package)(nil), pkgList[1:]...)
 	sort.Sort(byPath(list))
-	localpkg.SetImports(list)
+	p.ipkg.SetImports(list)
 
 	// package was imported completely and without errors
-	localpkg.MarkComplete()
+	p.ipkg.MarkComplete()
 
 	consumed, _ := r.Seek(0, io.SeekCurrent)
-	return int(consumed), localpkg, nil
+	return int(consumed), p.ipkg, nil
 }
 
 type iimporter struct {
-	ipath string
+	ipath   string
+	ipkg    *types.Package
+	version int
 
 	stringData  []byte
 	stringCache map[uint64]string
@@ -226,6 +227,9 @@ func (p *iimporter) pkgAt(off uint64) *types.Package {
 		return pkg
 	}
 	path := p.stringAt(off)
+	if path == p.ipath {
+		return p.ipkg
+	}
 	errorf("missing package %q in %q", path, p.ipath)
 	return nil
 }
@@ -255,6 +259,7 @@ type importReader struct {
 	currPkg    *types.Package
 	prevFile   string
 	prevLine   int64
+	prevColumn int64
 }
 
 func (r *importReader) obj(name string) {
@@ -448,6 +453,19 @@ func (r *importReader) qualifiedIdent() (*types.Package, string) {
 }
 
 func (r *importReader) pos() token.Pos {
+	if r.p.version >= 1 {
+		r.posv1()
+	} else {
+		r.posv0()
+	}
+
+	if r.prevFile == "" && r.prevLine == 0 && r.prevColumn == 0 {
+		return token.NoPos
+	}
+	return r.p.fake.pos(r.prevFile, int(r.prevLine), int(r.prevColumn))
+}
+
+func (r *importReader) posv0() {
 	delta := r.int64()
 	if delta != deltaNewFile {
 		r.prevLine += delta
@@ -457,12 +475,18 @@ func (r *importReader) pos() token.Pos {
 		r.prevFile = r.string()
 		r.prevLine = l
 	}
+}
 
-	if r.prevFile == "" && r.prevLine == 0 {
-		return token.NoPos
+func (r *importReader) posv1() {
+	delta := r.int64()
+	r.prevColumn += delta >> 1
+	if delta&1 != 0 {
+		delta = r.int64()
+		r.prevLine += delta >> 1
+		if delta&1 != 0 {
+			r.prevFile = r.string()
+		}
 	}
-
-	return r.p.fake.pos(r.prevFile, int(r.prevLine))
 }
 
 func (r *importReader) typ() types.Type {

vendor/golang.org/x/tools/go/internal/packagesdriver/sizes.go

@@ -81,21 +81,35 @@ func GetSizesGolist(ctx context.Context, buildFlags, env []string, dir string, u
 	args := []string{"list", "-f", "{{context.GOARCH}} {{context.Compiler}}"}
 	args = append(args, buildFlags...)
 	args = append(args, "--", "unsafe")
-	stdout, err := InvokeGo(ctx, env, dir, usesExportData, args...)
+	stdout, stderr, err := invokeGo(ctx, env, dir, usesExportData, args...)
+	var goarch, compiler string
 	if err != nil {
-		return nil, err
+		if strings.Contains(err.Error(), "cannot find main module") {
+			// User's running outside of a module. All bets are off. Get GOARCH and guess compiler is gc.
+			// TODO(matloob): Is this a problem in practice?
+			envout, _, enverr := invokeGo(ctx, env, dir, usesExportData, "env", "GOARCH")
+			if enverr != nil {
+				return nil, err
+			}
+			goarch = strings.TrimSpace(envout.String())
+			compiler = "gc"
+		} else {
+			return nil, err
+		}
+	} else {
+		fields := strings.Fields(stdout.String())
+		if len(fields) < 2 {
+			return nil, fmt.Errorf("could not parse GOARCH and Go compiler in format \"<GOARCH> <compiler>\" from stdout of go command:\n%s\ndir: %s\nstdout: <<%s>>\nstderr: <<%s>>",
+				cmdDebugStr(env, args...), dir, stdout.String(), stderr.String())
+		}
+		goarch = fields[0]
+		compiler = fields[1]
 	}
-	fields := strings.Fields(stdout.String())
-	if len(fields) < 2 {
-		return nil, fmt.Errorf("could not determine GOARCH and Go compiler")
-	}
-	goarch := fields[0]
-	compiler := fields[1]
 	return types.SizesFor(compiler, goarch), nil
 }
 
-// InvokeGo returns the stdout of a go command invocation.
-func InvokeGo(ctx context.Context, env []string, dir string, usesExportData bool, args ...string) (*bytes.Buffer, error) {
+// invokeGo returns the stdout and stderr of a go command invocation.
+func invokeGo(ctx context.Context, env []string, dir string, usesExportData bool, args ...string) (*bytes.Buffer, *bytes.Buffer, error) {
 	if debug {
 		defer func(start time.Time) { log.Printf("%s for %v", time.Since(start), cmdDebugStr(env, args...)) }(time.Now())
 	}
@@ -118,7 +132,7 @@ func InvokeGo(ctx context.Context, env []string, dir string, usesExportData bool
 			// Catastrophic error:
 			// - executable not found
 			// - context cancellation
-			return nil, fmt.Errorf("couldn't exec 'go %v': %s %T", args, err, err)
+			return nil, nil, fmt.Errorf("couldn't exec 'go %v': %s %T", args, err, err)
 		}
 
 		// Export mode entails a build.
@@ -126,7 +140,7 @@ func InvokeGo(ctx context.Context, env []string, dir string, usesExportData bool
 		// (despite the -e flag) and the Export field is blank.
 		// Do not fail in that case.
 		if !usesExportData {
-			return nil, fmt.Errorf("go %v: %s: %s", args, exitErr, stderr)
+			return nil, nil, fmt.Errorf("go %v: %s: %s", args, exitErr, stderr)
 		}
 	}
 
@@ -145,7 +159,7 @@ func InvokeGo(ctx context.Context, env []string, dir string, usesExportData bool
 		fmt.Fprintf(os.Stderr, "%s stdout: <<%s>>\n", cmdDebugStr(env, args...), stdout)
 	}
 
-	return stdout, nil
+	return stdout, stderr, nil
 }
 
 func cmdDebugStr(envlist []string, args ...string) string {

vendor/golang.org/x/tools/go/packages/BUILD.bazel

@@ -7,6 +7,7 @@ go_library(
         "external.go",
         "golist.go",
         "golist_overlay.go",
+        "loadmode_string.go",
         "packages.go",
         "visit.go",
     ],
@@ -18,5 +19,6 @@ go_library(
         "//vendor/golang.org/x/tools/go/internal/packagesdriver:go_default_library",
         "//vendor/golang.org/x/tools/internal/gopathwalk:go_default_library",
         "//vendor/golang.org/x/tools/internal/semver:go_default_library",
+        "//vendor/golang.org/x/tools/internal/span:go_default_library",
     ],
 )

vendor/golang.org/x/tools/go/packages/external.go

@@ -12,18 +12,34 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"os"
 	"os/exec"
 	"strings"
 )
 
-// Driver
+// The Driver Protocol
+//
+// The driver, given the inputs to a call to Load, returns metadata about the packages specified.
+// This allows for different build systems to support go/packages by telling go/packages how the
+// packages' source is organized.
+// The driver is a binary, either specified by the GOPACKAGESDRIVER environment variable or in
+// the path as gopackagesdriver. It's given the inputs to load in its argv. See the package
+// documentation in doc.go for the full description of the patterns that need to be supported.
+// A driver receives as a JSON-serialized driverRequest struct in standard input and will
+// produce a JSON-serialized driverResponse (see definition in packages.go) in its standard output.
+
+// driverRequest is used to provide the portion of Load's Config that is needed by a driver.
 type driverRequest struct {
-	Command    string            `json:"command"`
-	Mode       LoadMode          `json:"mode"`
-	Env        []string          `json:"env"`
-	BuildFlags []string          `json:"build_flags"`
-	Tests      bool              `json:"tests"`
-	Overlay    map[string][]byte `json:"overlay"`
+	Mode LoadMode `json:"mode"`
+	// Env specifies the environment the underlying build system should be run in.
+	Env []string `json:"env"`
+	// BuildFlags are flags that should be passed to the underlying build system.
+	BuildFlags []string `json:"build_flags"`
+	// Tests specifies whether the patterns should also return test packages.
+	Tests bool `json:"tests"`
+	// Overlay maps file paths (relative to the driver's working directory) to the byte contents
+	// of overlay files.
+	Overlay map[string][]byte `json:"overlay"`
 }
 
 // findExternalDriver returns the file path of a tool that supplies
@@ -61,12 +77,17 @@ func findExternalDriver(cfg *Config) driver {
 		}
 
 		buf := new(bytes.Buffer)
+		stderr := new(bytes.Buffer)
 		cmd := exec.CommandContext(cfg.Context, tool, words...)
 		cmd.Dir = cfg.Dir
 		cmd.Env = cfg.Env
 		cmd.Stdin = bytes.NewReader(req)
 		cmd.Stdout = buf
-		cmd.Stderr = new(bytes.Buffer)
+		cmd.Stderr = stderr
+		if len(stderr.Bytes()) != 0 && os.Getenv("GOPACKAGESPRINTDRIVERERRORS") != "" {
+			fmt.Fprintf(os.Stderr, "%s stderr: <<%s>>\n", cmdDebugStr(cmd, words...), stderr)
+		}
+
 		if err := cmd.Run(); err != nil {
 			return nil, fmt.Errorf("%v: %v: %s", tool, err, cmd.Stderr)
 		}

vendor/golang.org/x/tools/go/packages/golist.go

@@ -13,6 +13,7 @@ import (
 	"log"
 	"os"
 	"os/exec"
+	"path"
 	"path/filepath"
 	"reflect"
 	"regexp"
@@ -20,10 +21,12 @@ import (
 	"strings"
 	"sync"
 	"time"
+	"unicode"
 
 	"golang.org/x/tools/go/internal/packagesdriver"
 	"golang.org/x/tools/internal/gopathwalk"
 	"golang.org/x/tools/internal/semver"
+	"golang.org/x/tools/internal/span"
 )
 
 // debug controls verbose logging.
@@ -71,6 +74,28 @@ func (r *responseDeduper) addRoot(id string) {
 	r.dr.Roots = append(r.dr.Roots, id)
 }
 
+// goInfo contains global information from the go tool.
+type goInfo struct {
+	rootDirs map[string]string
+	env      goEnv
+}
+
+type goEnv struct {
+	modulesOn bool
+}
+
+func determineEnv(cfg *Config) goEnv {
+	buf, err := invokeGo(cfg, "env", "GOMOD")
+	if err != nil {
+		return goEnv{}
+	}
+	gomod := bytes.TrimSpace(buf.Bytes())
+
+	env := goEnv{}
+	env.modulesOn = len(gomod) > 0
+	return env
+}
+
 // goListDriver uses the go list command to interpret the patterns and produce
 // the build system package structure.
 // See driver for more details.
@@ -85,6 +110,33 @@ func goListDriver(cfg *Config, patterns ...string) (*driverResponse, error) {
 			sizeswg.Done()
 		}()
 	}
+	defer sizeswg.Wait()
+
+	// start fetching rootDirs
+	var info goInfo
+	var rootDirsReady, envReady = make(chan struct{}), make(chan struct{})
+	go func() {
+		info.rootDirs = determineRootDirs(cfg)
+		close(rootDirsReady)
+	}()
+	go func() {
+		info.env = determineEnv(cfg)
+		close(envReady)
+	}()
+	getGoInfo := func() *goInfo {
+		<-rootDirsReady
+		<-envReady
+		return &info
+	}
+
+	// Ensure that we don't leak goroutines: Load is synchronous, so callers will
+	// not expect it to access the fields of cfg after the call returns.
+	defer getGoInfo()
+
+	// always pass getGoInfo to golistDriver
+	golistDriver := func(cfg *Config, patterns ...string) (*driverResponse, error) {
+		return golistDriver(cfg, getGoInfo, patterns...)
+	}
 
 	// Determine files requested in contains patterns
 	var containFiles []string
@@ -147,7 +199,7 @@ extractQueries:
 	var containsCandidates []string
 
 	if len(containFiles) != 0 {
-		if err := runContainsQueries(cfg, golistDriver, response, containFiles); err != nil {
+		if err := runContainsQueries(cfg, golistDriver, response, containFiles, getGoInfo); err != nil {
 			return nil, err
 		}
 	}
@@ -158,7 +210,7 @@ extractQueries:
 		}
 	}
 
-	modifiedPkgs, needPkgs, err := processGolistOverlay(cfg, response)
+	modifiedPkgs, needPkgs, err := processGolistOverlay(cfg, response, getGoInfo)
 	if err != nil {
 		return nil, err
 	}
@@ -166,7 +218,7 @@ extractQueries:
 		containsCandidates = append(containsCandidates, modifiedPkgs...)
 		containsCandidates = append(containsCandidates, needPkgs...)
 	}
-	if err := addNeededOverlayPackages(cfg, golistDriver, response, needPkgs); err != nil {
+	if err := addNeededOverlayPackages(cfg, golistDriver, response, needPkgs, getGoInfo); err != nil {
 		return nil, err
 	}
 	// Check candidate packages for containFiles.
@@ -198,26 +250,30 @@ extractQueries:
 	return response.dr, nil
 }
 
-func addNeededOverlayPackages(cfg *Config, driver driver, response *responseDeduper, pkgs []string) error {
+func addNeededOverlayPackages(cfg *Config, driver driver, response *responseDeduper, pkgs []string, getGoInfo func() *goInfo) error {
 	if len(pkgs) == 0 {
 		return nil
 	}
-	dr, err := driver(cfg, pkgs...)
+	drivercfg := *cfg
+	if getGoInfo().env.modulesOn {
+		drivercfg.BuildFlags = append(drivercfg.BuildFlags, "-mod=readonly")
+	}
+	dr, err := driver(&drivercfg, pkgs...)
+
 	if err != nil {
 		return err
 	}
 	for _, pkg := range dr.Packages {
 		response.addPackage(pkg)
 	}
-	_, needPkgs, err := processGolistOverlay(cfg, response)
+	_, needPkgs, err := processGolistOverlay(cfg, response, getGoInfo)
 	if err != nil {
 		return err
 	}
-	addNeededOverlayPackages(cfg, driver, response, needPkgs)
-	return nil
+	return addNeededOverlayPackages(cfg, driver, response, needPkgs, getGoInfo)
 }
 
-func runContainsQueries(cfg *Config, driver driver, response *responseDeduper, queries []string) error {
+func runContainsQueries(cfg *Config, driver driver, response *responseDeduper, queries []string, goInfo func() *goInfo) error {
 	for _, query := range queries {
 		// TODO(matloob): Do only one query per directory.
 		fdir := filepath.Dir(query)
@@ -229,12 +285,41 @@ func runContainsQueries(cfg *Config, driver driver, response *responseDeduper, q
 		}
 		dirResponse, err := driver(cfg, pattern)
 		if err != nil {
-			// Couldn't find a package for the directory. Try to load the file as an ad-hoc package.
 			var queryErr error
-			dirResponse, err = driver(cfg, query)
-			if queryErr != nil {
-				// Return the original error if the attempt to fall back failed.
-				return err
+			if dirResponse, queryErr = adHocPackage(cfg, driver, pattern, query); queryErr != nil {
+				return err // return the original error
+			}
+		}
+		// `go list` can report errors for files that are not listed as part of a package's GoFiles.
+		// In the case of an invalid Go file, we should assume that it is part of package if only
+		// one package is in the response. The file may have valid contents in an overlay.
+		if len(dirResponse.Packages) == 1 {
+			pkg := dirResponse.Packages[0]
+			for i, err := range pkg.Errors {
+				s := errorSpan(err)
+				if !s.IsValid() {
+					break
+				}
+				if len(pkg.CompiledGoFiles) == 0 {
+					break
+				}
+				dir := filepath.Dir(pkg.CompiledGoFiles[0])
+				filename := filepath.Join(dir, filepath.Base(s.URI().Filename()))
+				if info, err := os.Stat(filename); err != nil || info.IsDir() {
+					break
+				}
+				if !contains(pkg.CompiledGoFiles, filename) {
+					pkg.CompiledGoFiles = append(pkg.CompiledGoFiles, filename)
+					pkg.GoFiles = append(pkg.GoFiles, filename)
+					pkg.Errors = append(pkg.Errors[:i], pkg.Errors[i+1:]...)
+				}
+			}
+		}
+		// A final attempt to construct an ad-hoc package.
+		if len(dirResponse.Packages) == 1 && len(dirResponse.Packages[0].Errors) == 1 {
+			var queryErr error
+			if dirResponse, queryErr = adHocPackage(cfg, driver, pattern, query); queryErr != nil {
+				return err // return the original error
 			}
 		}
 		isRoot := make(map[string]bool, len(dirResponse.Roots))
@@ -262,6 +347,75 @@ func runContainsQueries(cfg *Config, driver driver, response *responseDeduper, q
 	return nil
 }
 
+// adHocPackage attempts to construct an ad-hoc package given a query that failed.
+func adHocPackage(cfg *Config, driver driver, pattern, query string) (*driverResponse, error) {
+	// There was an error loading the package. Try to load the file as an ad-hoc package.
+	// Usually the error will appear in a returned package, but may not if we're in modules mode
+	// and the ad-hoc is located outside a module.
+	dirResponse, err := driver(cfg, query)
+	if err != nil {
+		return nil, err
+	}
+	// If we get nothing back from `go list`, try to make this file into its own ad-hoc package.
+	if len(dirResponse.Packages) == 0 && err == nil {
+		dirResponse.Packages = append(dirResponse.Packages, &Package{
+			ID:              "command-line-arguments",
+			PkgPath:         query,
+			GoFiles:         []string{query},
+			CompiledGoFiles: []string{query},
+			Imports:         make(map[string]*Package),
+		})
+		dirResponse.Roots = append(dirResponse.Roots, "command-line-arguments")
+	}
+	// Special case to handle issue #33482:
+	// If this is a file= query for ad-hoc packages where the file only exists on an overlay,
+	// and exists outside of a module, add the file in for the package.
+	if len(dirResponse.Packages) == 1 && (dirResponse.Packages[0].ID == "command-line-arguments" ||
+		filepath.ToSlash(dirResponse.Packages[0].PkgPath) == filepath.ToSlash(query)) {
+		if len(dirResponse.Packages[0].GoFiles) == 0 {
+			filename := filepath.Join(pattern, filepath.Base(query)) // avoid recomputing abspath
+			// TODO(matloob): check if the file is outside of a root dir?
+			for path := range cfg.Overlay {
+				if path == filename {
+					dirResponse.Packages[0].Errors = nil
+					dirResponse.Packages[0].GoFiles = []string{path}
+					dirResponse.Packages[0].CompiledGoFiles = []string{path}
+				}
+			}
+		}
+	}
+	return dirResponse, nil
+}
+
+func contains(files []string, filename string) bool {
+	for _, f := range files {
+		if f == filename {
+			return true
+		}
+	}
+	return false
+}
+
+// errorSpan attempts to parse a standard `go list` error message
+// by stripping off the trailing error message.
+//
+// It works only on errors whose message is prefixed by colon,
+// followed by a space (": "). For example:
+//
+//   attributes.go:13:1: expected 'package', found 'type'
+//
+func errorSpan(err Error) span.Span {
+	if err.Pos == "" {
+		input := strings.TrimSpace(err.Msg)
+		msgIndex := strings.Index(input, ": ")
+		if msgIndex < 0 {
+			return span.Parse(input)
+		}
+		return span.Parse(input[:msgIndex])
+	}
+	return span.Parse(err.Pos)
+}
+
 // modCacheRegexp splits a path in a module cache into module, module version, and package.
 var modCacheRegexp = regexp.MustCompile(`(.*)@([^/\\]*)(.*)`)
 
@@ -312,9 +466,7 @@ func runNamedQueries(cfg *Config, driver driver, response *responseDeduper, quer
 
 	startWalk := time.Now()
 	gopathwalk.Walk(roots, add, gopathwalk.Options{ModulesEnabled: modRoot != "", Debug: debug})
-	if debug {
-		log.Printf("%v for walk", time.Since(startWalk))
-	}
+	cfg.Logf("%v for walk", time.Since(startWalk))
 
 	// Weird special case: the top-level package in a module will be in
 	// whatever directory the user checked the repository out into. It's
@@ -327,6 +479,10 @@ func runNamedQueries(cfg *Config, driver driver, response *responseDeduper, quer
 		}
 
 		files, err := ioutil.ReadDir(modRoot)
+		if err != nil {
+			panic(err) // See above.
+		}
+
 		for _, f := range files {
 			if strings.HasSuffix(f.Name(), ".go") {
 				simpleMatches = append(simpleMatches, rel)
@@ -394,7 +550,7 @@ func runNamedQueries(cfg *Config, driver driver, response *responseDeduper, quer
 		// We're only trying to look at stuff in the module cache, so
 		// disable the network. This should speed things up, and has
 		// prevented errors in at least one case, #28518.
-		tmpCfg.Env = append(append([]string{"GOPROXY=off"}, cfg.Env...))
+		tmpCfg.Env = append([]string{"GOPROXY=off"}, cfg.Env...)
 
 		var err error
 		tmpCfg.Dir, err = ioutil.TempDir("", "gopackages-modquery")
@@ -442,17 +598,29 @@ func roots(cfg *Config) ([]gopathwalk.Root, string, error) {
 
 	var roots []gopathwalk.Root
 	// Always add GOROOT.
-	roots = append(roots, gopathwalk.Root{filepath.Join(goroot, "/src"), gopathwalk.RootGOROOT})
+	roots = append(roots, gopathwalk.Root{
+		Path: filepath.Join(goroot, "/src"),
+		Type: gopathwalk.RootGOROOT,
+	})
 	// If modules are enabled, scan the module dir.
 	if modDir != "" {
-		roots = append(roots, gopathwalk.Root{modDir, gopathwalk.RootCurrentModule})
+		roots = append(roots, gopathwalk.Root{
+			Path: modDir,
+			Type: gopathwalk.RootCurrentModule,
+		})
 	}
 	// Add either GOPATH/src or GOPATH/pkg/mod, depending on module mode.
 	for _, p := range gopath {
 		if modDir != "" {
-			roots = append(roots, gopathwalk.Root{filepath.Join(p, "/pkg/mod"), gopathwalk.RootModuleCache})
+			roots = append(roots, gopathwalk.Root{
+				Path: filepath.Join(p, "/pkg/mod"),
+				Type: gopathwalk.RootModuleCache,
+			})
 		} else {
-			roots = append(roots, gopathwalk.Root{filepath.Join(p, "/src"), gopathwalk.RootGOPATH})
+			roots = append(roots, gopathwalk.Root{
+				Path: filepath.Join(p, "/src"),
+				Type: gopathwalk.RootGOPATH,
+			})
 		}
 	}
 
@@ -565,13 +733,13 @@ func otherFiles(p *jsonPackage) [][]string {
 // golistDriver uses the "go list" command to expand the pattern
 // words and return metadata for the specified packages. dir may be
 // "" and env may be nil, as per os/exec.Command.
-func golistDriver(cfg *Config, words ...string) (*driverResponse, error) {
+func golistDriver(cfg *Config, rootsDirs func() *goInfo, words ...string) (*driverResponse, error) {
 	// go list uses the following identifiers in ImportPath and Imports:
 	//
 	// 	"p"			-- importable package or main (command)
-	//      "q.test"		-- q's test executable
+	// 	"q.test"		-- q's test executable
 	// 	"p [q.test]"		-- variant of p as built for q's test executable
-	//	"q_test [q.test]"	-- q's external test package
+	// 	"q_test [q.test]"	-- q's external test package
 	//
 	// The packages p that are built differently for a test q.test
 	// are q itself, plus any helpers used by the external test q_test,
@@ -606,6 +774,20 @@ func golistDriver(cfg *Config, words ...string) (*driverResponse, error) {
 			return nil, fmt.Errorf("package missing import path: %+v", p)
 		}
 
+		// Work around https://golang.org/issue/33157:
+		// go list -e, when given an absolute path, will find the package contained at
+		// that directory. But when no package exists there, it will return a fake package
+		// with an error and the ImportPath set to the absolute path provided to go list.
+		// Try to convert that absolute path to what its package path would be if it's
+		// contained in a known module or GOPATH entry. This will allow the package to be
+		// properly "reclaimed" when overlays are processed.
+		if filepath.IsAbs(p.ImportPath) && p.Error != nil {
+			pkgPath, ok := getPkgPath(cfg, p.ImportPath, rootsDirs)
+			if ok {
+				p.ImportPath = pkgPath
+			}
+		}
+
 		if old, found := seen[p.ImportPath]; found {
 			if !reflect.DeepEqual(p, old) {
 				return nil, fmt.Errorf("internal error: go list gives conflicting information for package %v", p.ImportPath)
@@ -709,6 +891,44 @@ func golistDriver(cfg *Config, words ...string) (*driverResponse, error) {
 	return &response, nil
 }
 
+// getPkgPath finds the package path of a directory if it's relative to a root directory.
+func getPkgPath(cfg *Config, dir string, goInfo func() *goInfo) (string, bool) {
+	absDir, err := filepath.Abs(dir)
+	if err != nil {
+		cfg.Logf("error getting absolute path of %s: %v", dir, err)
+		return "", false
+	}
+	for rdir, rpath := range goInfo().rootDirs {
+		absRdir, err := filepath.Abs(rdir)
+		if err != nil {
+			cfg.Logf("error getting absolute path of %s: %v", rdir, err)
+			continue
+		}
+		// Make sure that the directory is in the module,
+		// to avoid creating a path relative to another module.
+		if !strings.HasPrefix(absDir, absRdir) {
+			cfg.Logf("%s does not have prefix %s", absDir, absRdir)
+			continue
+		}
+		// TODO(matloob): This doesn't properly handle symlinks.
+		r, err := filepath.Rel(rdir, dir)
+		if err != nil {
+			continue
+		}
+		if rpath != "" {
+			// We choose only one root even though the directory even it can belong in multiple modules
+			// or GOPATH entries. This is okay because we only need to work with absolute dirs when a
+			// file is missing from disk, for instance when gopls calls go/packages in an overlay.
+			// Once the file is saved, gopls, or the next invocation of the tool will get the correct
+			// result straight from golist.
+			// TODO(matloob): Implement module tiebreaking?
+			return path.Join(rpath, filepath.ToSlash(r)), true
+		}
+		return filepath.ToSlash(r), true
+	}
+	return "", false
+}
+
 // absJoin absolutizes and flattens the lists of files.
 func absJoin(dir string, fileses ...[]string) (res []string) {
 	for _, files := range fileses {
@@ -729,7 +949,7 @@ func golistargs(cfg *Config, words []string) []string {
 		fmt.Sprintf("-compiled=%t", cfg.Mode&(NeedCompiledGoFiles|NeedSyntax|NeedTypesInfo|NeedTypesSizes) != 0),
 		fmt.Sprintf("-test=%t", cfg.Tests),
 		fmt.Sprintf("-export=%t", usesExportData(cfg)),
-		fmt.Sprintf("-deps=%t", cfg.Mode&NeedDeps != 0),
+		fmt.Sprintf("-deps=%t", cfg.Mode&NeedImports != 0),
 		// go list doesn't let you pass -test and -find together,
 		// probably because you'd just get the TestMain.
 		fmt.Sprintf("-find=%t", !cfg.Tests && cfg.Mode&findFlags == 0),
@@ -755,11 +975,9 @@ func invokeGo(cfg *Config, args ...string) (*bytes.Buffer, error) {
 	cmd.Dir = cfg.Dir
 	cmd.Stdout = stdout
 	cmd.Stderr = stderr
-	if debug {
-		defer func(start time.Time) {
-			log.Printf("%s for %v, stderr: <<%s>>\n", time.Since(start), cmdDebugStr(cmd, args...), stderr)
-		}(time.Now())
-	}
+	defer func(start time.Time) {
+		cfg.Logf("%s for %v, stderr: <<%s>> stdout: <<%s>>\n", time.Since(start), cmdDebugStr(cmd, args...), stderr, stdout)
+	}(time.Now())
 
 	if err := cmd.Run(); err != nil {
 		// Check for 'go' executable not being found.
@@ -779,6 +997,30 @@ func invokeGo(cfg *Config, args ...string) (*bytes.Buffer, error) {
 			return nil, goTooOldError{fmt.Errorf("unsupported version of go: %s: %s", exitErr, stderr)}
 		}
 
+		// Related to #24854
+		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), "unexpected directory layout") {
+			return nil, fmt.Errorf("%s", stderr.String())
+		}
+
+		// Is there an error running the C compiler in cgo? This will be reported in the "Error" field
+		// and should be suppressed by go list -e.
+		//
+		// This condition is not perfect yet because the error message can include other error messages than runtime/cgo.
+		isPkgPathRune := func(r rune) bool {
+			// From https://golang.org/ref/spec#Import_declarations:
+			//    Implementation restriction: A compiler may restrict ImportPaths to non-empty strings
+			//    using only characters belonging to Unicode's L, M, N, P, and S general categories
+			//    (the Graphic characters without spaces) and may also exclude the
+			//    characters !"#$%&'()*,:;<=>?[\]^`{|} and the Unicode replacement character U+FFFD.
+			return unicode.IsOneOf([]*unicode.RangeTable{unicode.L, unicode.M, unicode.N, unicode.P, unicode.S}, r) &&
+				!strings.ContainsRune("!\"#$%&'()*,:;<=>?[\\]^`{|}\uFFFD", r)
+		}
+		if len(stderr.String()) > 0 && strings.HasPrefix(stderr.String(), "# ") {
+			if strings.HasPrefix(strings.TrimLeftFunc(stderr.String()[len("# "):], isPkgPathRune), "\n") {
+				return stdout, nil
+			}
+		}
+
 		// This error only appears in stderr. See golang.org/cl/166398 for a fix in go list to show
 		// the error in the Err section of stdout in case -e option is provided.
 		// This fix is provided for backwards compatibility.
@@ -788,17 +1030,58 @@ func invokeGo(cfg *Config, args ...string) (*bytes.Buffer, error) {
 			return bytes.NewBufferString(output), nil
 		}
 
+		// Similar to the previous error, but currently lacks a fix in Go.
+		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), "named files must all be in one directory") {
+			output := fmt.Sprintf(`{"ImportPath": "command-line-arguments","Incomplete": true,"Error": {"Pos": "","Err": %q}}`,
+				strings.Trim(stderr.String(), "\n"))
+			return bytes.NewBufferString(output), nil
+		}
+
+		// Backwards compatibility for Go 1.11 because 1.12 and 1.13 put the directory in the ImportPath.
+		// If the package doesn't exist, put the absolute path of the directory into the error message,
+		// as Go 1.13 list does.
+		const noSuchDirectory = "no such directory"
+		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), noSuchDirectory) {
+			errstr := stderr.String()
+			abspath := strings.TrimSpace(errstr[strings.Index(errstr, noSuchDirectory)+len(noSuchDirectory):])
+			output := fmt.Sprintf(`{"ImportPath": %q,"Incomplete": true,"Error": {"Pos": "","Err": %q}}`,
+				abspath, strings.Trim(stderr.String(), "\n"))
+			return bytes.NewBufferString(output), nil
+		}
+
 		// Workaround for #29280: go list -e has incorrect behavior when an ad-hoc package doesn't exist.
+		// Note that the error message we look for in this case is different that the one looked for above.
 		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), "no such file or directory") {
 			output := fmt.Sprintf(`{"ImportPath": "command-line-arguments","Incomplete": true,"Error": {"Pos": "","Err": %q}}`,
 				strings.Trim(stderr.String(), "\n"))
 			return bytes.NewBufferString(output), nil
 		}
 
+		// Workaround for #34273. go list -e with GO111MODULE=on has incorrect behavior when listing a
+		// directory outside any module.
+		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), "outside available modules") {
+			output := fmt.Sprintf(`{"ImportPath": %q,"Incomplete": true,"Error": {"Pos": "","Err": %q}}`,
+				// TODO(matloob): command-line-arguments isn't correct here.
+				"command-line-arguments", strings.Trim(stderr.String(), "\n"))
+			return bytes.NewBufferString(output), nil
+		}
+
+		// Another variation of the previous error
+		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), "outside module root") {
+			output := fmt.Sprintf(`{"ImportPath": %q,"Incomplete": true,"Error": {"Pos": "","Err": %q}}`,
+				// TODO(matloob): command-line-arguments isn't correct here.
+				"command-line-arguments", strings.Trim(stderr.String(), "\n"))
+			return bytes.NewBufferString(output), nil
+		}
+
 		// Workaround for an instance of golang.org/issue/26755: go list -e  will return a non-zero exit
 		// status if there's a dependency on a package that doesn't exist. But it should return
 		// a zero exit status and set an error on that package.
 		if len(stderr.String()) > 0 && strings.Contains(stderr.String(), "no Go files in") {
+			// Don't clobber stdout if `go list` actually returned something.
+			if len(stdout.String()) > 0 {
+				return stdout, nil
+			}
 			// try to extract package name from string
 			stderrStr := stderr.String()
 			var importPath string
@@ -832,12 +1115,6 @@ func invokeGo(cfg *Config, args ...string) (*bytes.Buffer, error) {
 	if len(stderr.Bytes()) != 0 && os.Getenv("GOPACKAGESPRINTGOLISTERRORS") != "" {
 		fmt.Fprintf(os.Stderr, "%s stderr: <<%s>>\n", cmdDebugStr(cmd, args...), stderr)
 	}
-
-	// debugging
-	if false {
-		fmt.Fprintf(os.Stderr, "%s stdout: <<%s>>\n", cmdDebugStr(cmd, args...), stdout)
-	}
-
 	return stdout, nil
 }
 

vendor/golang.org/x/tools/go/packages/golist_overlay.go

@@ -6,11 +6,9 @@ import (
 	"fmt"
 	"go/parser"
 	"go/token"
-	"path"
 	"path/filepath"
 	"strconv"
 	"strings"
-	"sync"
 )
 
 // processGolistOverlay provides rudimentary support for adding
@@ -18,7 +16,7 @@ import (
 // sometimes incorrect.
 // TODO(matloob): Handle unsupported cases, including the following:
 // - determining the correct package to add given a new import path
-func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs, needPkgs []string, err error) {
+func processGolistOverlay(cfg *Config, response *responseDeduper, rootDirs func() *goInfo) (modifiedPkgs, needPkgs []string, err error) {
 	havePkgs := make(map[string]string) // importPath -> non-test package ID
 	needPkgsSet := make(map[string]bool)
 	modifiedPkgsSet := make(map[string]bool)
@@ -29,16 +27,20 @@ func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs,
 		havePkgs[pkg.PkgPath] = pkg.ID
 	}
 
-	var rootDirs map[string]string
-	var onceGetRootDirs sync.Once
+	// If no new imports are added, it is safe to avoid loading any needPkgs.
+	// Otherwise, it's hard to tell which package is actually being loaded
+	// (due to vendoring) and whether any modified package will show up
+	// in the transitive set of dependencies (because new imports are added,
+	// potentially modifying the transitive set of dependencies).
+	var overlayAddsImports bool
 
 	for opath, contents := range cfg.Overlay {
 		base := filepath.Base(opath)
 		dir := filepath.Dir(opath)
-		var pkg *Package
+		var pkg *Package           // if opath belongs to both a package and its test variant, this will be the test variant
 		var testVariantOf *Package // if opath is a test file, this is the package it is testing
 		var fileExists bool
-		isTest := strings.HasSuffix(opath, "_test.go")
+		isTestFile := strings.HasSuffix(opath, "_test.go")
 		pkgName, ok := extractPackageName(opath, contents)
 		if !ok {
 			// Don't bother adding a file that doesn't even have a parsable package statement
@@ -47,20 +49,33 @@ func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs,
 		}
 	nextPackage:
 		for _, p := range response.dr.Packages {
-			if pkgName != p.Name {
+			if pkgName != p.Name && p.ID != "command-line-arguments" {
 				continue
 			}
 			for _, f := range p.GoFiles {
 				if !sameFile(filepath.Dir(f), dir) {
 					continue
 				}
-				if isTest && !hasTestFiles(p) {
+				// Make sure to capture information on the package's test variant, if needed.
+				if isTestFile && !hasTestFiles(p) {
 					// TODO(matloob): Are there packages other than the 'production' variant
 					// of a package that this can match? This shouldn't match the test main package
 					// because the file is generated in another directory.
 					testVariantOf = p
 					continue nextPackage
 				}
+				if pkg != nil && p != pkg && pkg.PkgPath == p.PkgPath {
+					// If we've already seen the test variant,
+					// make sure to label which package it is a test variant of.
+					if hasTestFiles(pkg) {
+						testVariantOf = p
+						continue nextPackage
+					}
+					// If we have already seen the package of which this is a test variant.
+					if hasTestFiles(p) {
+						testVariantOf = pkg
+					}
+				}
 				pkg = p
 				if filepath.Base(f) == base {
 					fileExists = true
@@ -69,37 +84,18 @@ func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs,
 		}
 		// The overlay could have included an entirely new package.
 		if pkg == nil {
-			onceGetRootDirs.Do(func() {
-				rootDirs = determineRootDirs(cfg)
-			})
 			// Try to find the module or gopath dir the file is contained in.
 			// Then for modules, add the module opath to the beginning.
-			var pkgPath string
-			for rdir, rpath := range rootDirs {
-				// TODO(matloob): This doesn't properly handle symlinks.
-				r, err := filepath.Rel(rdir, dir)
-				if err != nil {
-					continue
-				}
-				pkgPath = filepath.ToSlash(r)
-				if rpath != "" {
-					pkgPath = path.Join(rpath, pkgPath)
-				}
-				// We only create one new package even it can belong in multiple modules or GOPATH entries.
-				// This is okay because tools (such as the LSP) that use overlays will recompute the overlay
-				// once the file is saved, and golist will do the right thing.
-				// TODO(matloob): Implement module tiebreaking?
+			pkgPath, ok := getPkgPath(cfg, dir, rootDirs)
+			if !ok {
 				break
 			}
-			if pkgPath == "" {
-				continue
-			}
 			isXTest := strings.HasSuffix(pkgName, "_test")
 			if isXTest {
 				pkgPath += "_test"
 			}
 			id := pkgPath
-			if isTest && !isXTest {
+			if isTestFile && !isXTest {
 				id = fmt.Sprintf("%s [%s.test]", pkgPath, pkgPath)
 			}
 			// Try to reclaim a package with the same id if it exists in the response.
@@ -115,7 +111,7 @@ func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs,
 				response.addPackage(pkg)
 				havePkgs[pkg.PkgPath] = id
 				// Add the production package's sources for a test variant.
-				if isTest && !isXTest && testVariantOf != nil {
+				if isTestFile && !isXTest && testVariantOf != nil {
 					pkg.GoFiles = append(pkg.GoFiles, testVariantOf.GoFiles...)
 					pkg.CompiledGoFiles = append(pkg.CompiledGoFiles, testVariantOf.CompiledGoFiles...)
 				}
@@ -136,13 +132,18 @@ func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs,
 		for _, imp := range imports {
 			_, found := pkg.Imports[imp]
 			if !found {
+				overlayAddsImports = true
 				// TODO(matloob): Handle cases when the following block isn't correct.
-				// These include imports of test variants, imports of vendored packages, etc.
+				// These include imports of vendored packages, etc.
 				id, ok := havePkgs[imp]
 				if !ok {
 					id = imp
 				}
 				pkg.Imports[imp] = &Package{ID: id}
+				// Add dependencies to the non-test variant version of this package as wel.
+				if testVariantOf != nil {
+					testVariantOf.Imports[imp] = &Package{ID: id}
+				}
 			}
 		}
 		continue
@@ -171,9 +172,11 @@ func processGolistOverlay(cfg *Config, response *responseDeduper) (modifiedPkgs,
 		}
 	}
 
-	needPkgs = make([]string, 0, len(needPkgsSet))
-	for pkg := range needPkgsSet {
-		needPkgs = append(needPkgs, pkg)
+	if overlayAddsImports {
+		needPkgs = make([]string, 0, len(needPkgsSet))
+		for pkg := range needPkgsSet {
+			needPkgs = append(needPkgs, pkg)
+		}
 	}
 	modifiedPkgs = make([]string, 0, len(modifiedPkgsSet))
 	for pkg := range modifiedPkgsSet {

vendor/golang.org/x/tools/go/packages/loadmode_string.go

@@ -0,0 +1,57 @@
+// Copyright 2019 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 packages
+
+import (
+	"fmt"
+	"strings"
+)
+
+var allModes = []LoadMode{
+	NeedName,
+	NeedFiles,
+	NeedCompiledGoFiles,
+	NeedImports,
+	NeedDeps,
+	NeedExportsFile,
+	NeedTypes,
+	NeedSyntax,
+	NeedTypesInfo,
+	NeedTypesSizes,
+}
+
+var modeStrings = []string{
+	"NeedName",
+	"NeedFiles",
+	"NeedCompiledGoFiles",
+	"NeedImports",
+	"NeedDeps",
+	"NeedExportsFile",
+	"NeedTypes",
+	"NeedSyntax",
+	"NeedTypesInfo",
+	"NeedTypesSizes",
+}
+
+func (mod LoadMode) String() string {
+	m := mod
+	if m == 0 {
+		return fmt.Sprintf("LoadMode(0)")
+	}
+	var out []string
+	for i, x := range allModes {
+		if x > m {
+			break
+		}
+		if (m & x) != 0 {
+			out = append(out, modeStrings[i])
+			m = m ^ x
+		}
+	}
+	if m != 0 {
+		out = append(out, "Unknown")
+	}
+	return fmt.Sprintf("LoadMode(%s)", strings.Join(out, "|"))
+}

vendor/golang.org/x/tools/go/packages/packages.go

@@ -48,8 +48,7 @@ const (
 	// "placeholder" Packages with only the ID set.
 	NeedImports
 
-	// NeedDeps adds the fields requested by the LoadMode in the packages in Imports. If NeedImports
-	// is not set NeedDeps has no effect.
+	// NeedDeps adds the fields requested by the LoadMode in the packages in Imports.
 	NeedDeps
 
 	// NeedExportsFile adds ExportsFile.
@@ -75,7 +74,7 @@ const (
 
 	// Deprecated: LoadImports exists for historical compatibility
 	// and should not be used. Please directly specify the needed fields using the Need values.
-	LoadImports = LoadFiles | NeedImports | NeedDeps
+	LoadImports = LoadFiles | NeedImports
 
 	// Deprecated: LoadTypes exists for historical compatibility
 	// and should not be used. Please directly specify the needed fields using the Need values.
@@ -87,7 +86,7 @@ const (
 
 	// Deprecated: LoadAllSyntax exists for historical compatibility
 	// and should not be used. Please directly specify the needed fields using the Need values.
-	LoadAllSyntax = LoadSyntax
+	LoadAllSyntax = LoadSyntax | NeedDeps
 )
 
 // A Config specifies details about how packages should be loaded.
@@ -103,6 +102,12 @@ type Config struct {
 	// If Context is nil, the load cannot be cancelled.
 	Context context.Context
 
+	// Logf is the logger for the config.
+	// If the user provides a logger, debug logging is enabled.
+	// If the GOPACKAGESDEBUG environment variable is set to true,
+	// but the logger is nil, default to log.Printf.
+	Logf func(format string, args ...interface{})
+
 	// Dir is the directory in which to run the build system's query tool
 	// that provides information about the packages.
 	// If Dir is empty, the tool is run in the current directory.
@@ -410,11 +415,13 @@ type loader struct {
 	parseCacheMu sync.Mutex
 	exportMu     sync.Mutex // enforces mutual exclusion of exportdata operations
 
-	// TODO(matloob): Add an implied mode here and use that instead of mode.
-	// Implied mode would contain all the fields we need the data for so we can
-	// get the actually requested fields. We'll zero them out before returning
-	// packages to the user. This will make it easier for us to get the conditions
-	// where we need certain modes right.
+	// Config.Mode contains the implied mode (see impliedLoadMode).
+	// Implied mode contains all the fields we need the data for.
+	// In requestedMode there are the actually requested fields.
+	// We'll zero them out before returning packages to the user.
+	// This makes it easier for us to get the conditions where
+	// we need certain modes right.
+	requestedMode LoadMode
 }
 
 type parseValue struct {
@@ -429,6 +436,17 @@ func newLoader(cfg *Config) *loader {
 	}
 	if cfg != nil {
 		ld.Config = *cfg
+		// If the user has provided a logger, use it.
+		ld.Config.Logf = cfg.Logf
+	}
+	if ld.Config.Logf == nil {
+		// If the GOPACKAGESDEBUG environment variable is set to true,
+		// but the user has not provided a logger, default to log.Printf.
+		if debug {
+			ld.Config.Logf = log.Printf
+		} else {
+			ld.Config.Logf = func(format string, args ...interface{}) {}
+		}
 	}
 	if ld.Config.Mode == 0 {
 		ld.Config.Mode = NeedName | NeedFiles | NeedCompiledGoFiles // Preserve zero behavior of Mode for backwards compatibility.
@@ -445,7 +463,11 @@ func newLoader(cfg *Config) *loader {
 		}
 	}
 
-	if ld.Mode&NeedTypes != 0 {
+	// Save the actually requested fields. We'll zero them out before returning packages to the user.
+	ld.requestedMode = ld.Mode
+	ld.Mode = impliedLoadMode(ld.Mode)
+
+	if ld.Mode&NeedTypes != 0 || ld.Mode&NeedSyntax != 0 {
 		if ld.Fset == nil {
 			ld.Fset = token.NewFileSet()
 		}
@@ -459,6 +481,7 @@ func newLoader(cfg *Config) *loader {
 			}
 		}
 	}
+
 	return ld
 }
 
@@ -479,8 +502,8 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 		}
 		lpkg := &loaderPackage{
 			Package:   pkg,
-			needtypes: (ld.Mode&(NeedTypes|NeedTypesInfo) != 0 && rootIndex < 0) || rootIndex >= 0,
-			needsrc: (ld.Mode&(NeedSyntax|NeedTypesInfo) != 0 && rootIndex < 0) || rootIndex >= 0 ||
+			needtypes: (ld.Mode&(NeedTypes|NeedTypesInfo) != 0 && ld.Mode&NeedDeps != 0 && rootIndex < 0) || rootIndex >= 0,
+			needsrc: (ld.Mode&(NeedSyntax|NeedTypesInfo) != 0 && ld.Mode&NeedDeps != 0 && rootIndex < 0) || rootIndex >= 0 ||
 				len(ld.Overlay) > 0 || // Overlays can invalidate export data. TODO(matloob): make this check fine-grained based on dependencies on overlaid files
 				pkg.ExportFile == "" && pkg.PkgPath != "unsafe",
 		}
@@ -527,28 +550,31 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 		lpkg.color = grey
 		stack = append(stack, lpkg) // push
 		stubs := lpkg.Imports       // the structure form has only stubs with the ID in the Imports
-		lpkg.Imports = make(map[string]*Package, len(stubs))
-		for importPath, ipkg := range stubs {
-			var importErr error
-			imp := ld.pkgs[ipkg.ID]
-			if imp == nil {
-				// (includes package "C" when DisableCgo)
-				importErr = fmt.Errorf("missing package: %q", ipkg.ID)
-			} else if imp.color == grey {
-				importErr = fmt.Errorf("import cycle: %s", stack)
-			}
-			if importErr != nil {
-				if lpkg.importErrors == nil {
-					lpkg.importErrors = make(map[string]error)
+		// If NeedImports isn't set, the imports fields will all be zeroed out.
+		if ld.Mode&NeedImports != 0 {
+			lpkg.Imports = make(map[string]*Package, len(stubs))
+			for importPath, ipkg := range stubs {
+				var importErr error
+				imp := ld.pkgs[ipkg.ID]
+				if imp == nil {
+					// (includes package "C" when DisableCgo)
+					importErr = fmt.Errorf("missing package: %q", ipkg.ID)
+				} else if imp.color == grey {
+					importErr = fmt.Errorf("import cycle: %s", stack)
+				}
+				if importErr != nil {
+					if lpkg.importErrors == nil {
+						lpkg.importErrors = make(map[string]error)
+					}
+					lpkg.importErrors[importPath] = importErr
+					continue
 				}
-				lpkg.importErrors[importPath] = importErr
-				continue
-			}
 
-			if visit(imp) {
-				lpkg.needsrc = true
+				if visit(imp) {
+					lpkg.needsrc = true
+				}
+				lpkg.Imports[importPath] = imp.Package
 			}
-			lpkg.Imports[importPath] = imp.Package
 		}
 		if lpkg.needsrc {
 			srcPkgs = append(srcPkgs, lpkg)
@@ -562,7 +588,7 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 		return lpkg.needsrc
 	}
 
-	if ld.Mode&(NeedImports|NeedDeps) == 0 {
+	if ld.Mode&NeedImports == 0 {
 		// We do this to drop the stub import packages that we are not even going to try to resolve.
 		for _, lpkg := range initial {
 			lpkg.Imports = nil
@@ -573,7 +599,7 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 			visit(lpkg)
 		}
 	}
-	if ld.Mode&NeedDeps != 0 { // TODO(matloob): This is only the case if NeedTypes is also set, right?
+	if ld.Mode&NeedImports != 0 && ld.Mode&NeedTypes != 0 {
 		for _, lpkg := range srcPkgs {
 			// Complete type information is required for the
 			// immediate dependencies of each source package.
@@ -583,9 +609,9 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 			}
 		}
 	}
-	// Load type data if needed, starting at
+	// Load type data and syntax if needed, starting at
 	// the initial packages (roots of the import DAG).
-	if ld.Mode&NeedTypes != 0 {
+	if ld.Mode&NeedTypes != 0 || ld.Mode&NeedSyntax != 0 {
 		var wg sync.WaitGroup
 		for _, lpkg := range initial {
 			wg.Add(1)
@@ -598,54 +624,44 @@ func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) {
 	}
 
 	result := make([]*Package, len(initial))
-	importPlaceholders := make(map[string]*Package)
 	for i, lpkg := range initial {
 		result[i] = lpkg.Package
 	}
 	for i := range ld.pkgs {
 		// Clear all unrequested fields, for extra de-Hyrum-ization.
-		if ld.Mode&NeedName == 0 {
+		if ld.requestedMode&NeedName == 0 {
 			ld.pkgs[i].Name = ""
 			ld.pkgs[i].PkgPath = ""
 		}
-		if ld.Mode&NeedFiles == 0 {
+		if ld.requestedMode&NeedFiles == 0 {
 			ld.pkgs[i].GoFiles = nil
 			ld.pkgs[i].OtherFiles = nil
 		}
-		if ld.Mode&NeedCompiledGoFiles == 0 {
+		if ld.requestedMode&NeedCompiledGoFiles == 0 {
 			ld.pkgs[i].CompiledGoFiles = nil
 		}
-		if ld.Mode&NeedImports == 0 {
+		if ld.requestedMode&NeedImports == 0 {
 			ld.pkgs[i].Imports = nil
 		}
-		if ld.Mode&NeedExportsFile == 0 {
+		if ld.requestedMode&NeedExportsFile == 0 {
 			ld.pkgs[i].ExportFile = ""
 		}
-		if ld.Mode&NeedTypes == 0 {
+		if ld.requestedMode&NeedTypes == 0 {
 			ld.pkgs[i].Types = nil
 			ld.pkgs[i].Fset = nil
 			ld.pkgs[i].IllTyped = false
 		}
-		if ld.Mode&NeedSyntax == 0 {
+		if ld.requestedMode&NeedSyntax == 0 {
 			ld.pkgs[i].Syntax = nil
 		}
-		if ld.Mode&NeedTypesInfo == 0 {
+		if ld.requestedMode&NeedTypesInfo == 0 {
 			ld.pkgs[i].TypesInfo = nil
 		}
-		if ld.Mode&NeedTypesSizes == 0 {
+		if ld.requestedMode&NeedTypesSizes == 0 {
 			ld.pkgs[i].TypesSizes = nil
 		}
-		if ld.Mode&NeedDeps == 0 {
-			for j, pkg := range ld.pkgs[i].Imports {
-				ph, ok := importPlaceholders[pkg.ID]
-				if !ok {
-					ph = &Package{ID: pkg.ID}
-					importPlaceholders[pkg.ID] = ph
-				}
-				ld.pkgs[i].Imports[j] = ph
-			}
-		}
 	}
+
 	return result, nil
 }
 
@@ -666,7 +682,6 @@ func (ld *loader) loadRecursive(lpkg *loaderPackage) {
 			}(imp)
 		}
 		wg.Wait()
-
 		ld.loadPackage(lpkg)
 	})
 }
@@ -755,12 +770,23 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 		lpkg.Errors = append(lpkg.Errors, errs...)
 	}
 
+	if ld.Config.Mode&NeedTypes != 0 && len(lpkg.CompiledGoFiles) == 0 && lpkg.ExportFile != "" {
+		// The config requested loading sources and types, but sources are missing.
+		// Add an error to the package and fall back to loading from export data.
+		appendError(Error{"-", fmt.Sprintf("sources missing for package %s", lpkg.ID), ParseError})
+		ld.loadFromExportData(lpkg)
+		return // can't get syntax trees for this package
+	}
+
 	files, errs := ld.parseFiles(lpkg.CompiledGoFiles)
 	for _, err := range errs {
 		appendError(err)
 	}
 
 	lpkg.Syntax = files
+	if ld.Config.Mode&NeedTypes == 0 {
+		return
+	}
 
 	lpkg.TypesInfo = &types.Info{
 		Types:      make(map[ast.Expr]types.TypeAndValue),
@@ -793,7 +819,7 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 		if ipkg.Types != nil && ipkg.Types.Complete() {
 			return ipkg.Types, nil
 		}
-		log.Fatalf("internal error: nil Pkg importing %q from %q", path, lpkg)
+		log.Fatalf("internal error: package %q without types was imported from %q", path, lpkg)
 		panic("unreachable")
 	})
 
@@ -804,7 +830,7 @@ func (ld *loader) loadPackage(lpkg *loaderPackage) {
 		// Type-check bodies of functions only in non-initial packages.
 		// Example: for import graph A->B->C and initial packages {A,C},
 		// we can ignore function bodies in B.
-		IgnoreFuncBodies: (ld.Mode&(NeedDeps|NeedTypesInfo) == 0) && !lpkg.initial,
+		IgnoreFuncBodies: ld.Mode&NeedDeps == 0 && !lpkg.initial,
 
 		Error: appendError,
 		Sizes: ld.sizes,
@@ -1066,6 +1092,25 @@ func (ld *loader) loadFromExportData(lpkg *loaderPackage) (*types.Package, error
 	return tpkg, nil
 }
 
-func usesExportData(cfg *Config) bool {
-	return cfg.Mode&NeedExportsFile != 0 || cfg.Mode&NeedTypes != 0 && cfg.Mode&NeedTypesInfo == 0
+// impliedLoadMode returns loadMode with its dependencies.
+func impliedLoadMode(loadMode LoadMode) LoadMode {
+	if loadMode&NeedTypesInfo != 0 && loadMode&NeedImports == 0 {
+		// If NeedTypesInfo, go/packages needs to do typechecking itself so it can
+		// associate type info with the AST. To do so, we need the export data
+		// for dependencies, which means we need to ask for the direct dependencies.
+		// NeedImports is used to ask for the direct dependencies.
+		loadMode |= NeedImports
+	}
+
+	if loadMode&NeedDeps != 0 && loadMode&NeedImports == 0 {
+		// With NeedDeps we need to load at least direct dependencies.
+		// NeedImports is used to ask for the direct dependencies.
+		loadMode |= NeedImports
+	}
+
+	return loadMode
+}
+
+func usesExportData(cfg *Config) bool {
+	return cfg.Mode&NeedExportsFile != 0 || cfg.Mode&NeedTypes != 0 && cfg.Mode&NeedDeps == 0
 }

vendor/golang.org/x/tools/go/types/objectpath/objectpath.go

@@ -376,7 +376,7 @@ func Object(pkg *types.Package, p Path) (types.Object, error) {
 		return nil, fmt.Errorf("package %s does not contain %q", pkg.Path(), pkgobj)
 	}
 
-	// abtraction of *types.{Pointer,Slice,Array,Chan,Map}
+	// abstraction of *types.{Pointer,Slice,Array,Chan,Map}
 	type hasElem interface {
 		Elem() types.Type
 	}

vendor/golang.org/x/tools/internal/gopathwalk/walk.go

@@ -16,6 +16,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"golang.org/x/tools/internal/fastwalk"
 )
@@ -59,24 +60,38 @@ func SrcDirsRoots(ctx *build.Context) []Root {
 // paths of the containing source directory and the package directory.
 // add will be called concurrently.
 func Walk(roots []Root, add func(root Root, dir string), opts Options) {
+	WalkSkip(roots, add, func(Root, string) bool { return false }, opts)
+}
+
+// WalkSkip walks Go source directories ($GOROOT, $GOPATH, etc) to find packages.
+// For each package found, add will be called (concurrently) with the absolute
+// paths of the containing source directory and the package directory.
+// For each directory that will be scanned, skip will be called (concurrently)
+// with the absolute paths of the containing source directory and the directory.
+// If skip returns false on a directory it will be processed.
+// add will be called concurrently.
+// skip will be called concurrently.
+func WalkSkip(roots []Root, add func(root Root, dir string), skip func(root Root, dir string) bool, opts Options) {
 	for _, root := range roots {
-		walkDir(root, add, opts)
+		walkDir(root, add, skip, opts)
 	}
 }
 
-func walkDir(root Root, add func(Root, string), opts Options) {
+func walkDir(root Root, add func(Root, string), skip func(root Root, dir string) bool, opts Options) {
 	if _, err := os.Stat(root.Path); os.IsNotExist(err) {
 		if opts.Debug {
-			log.Printf("skipping nonexistant directory: %v", root.Path)
+			log.Printf("skipping nonexistent directory: %v", root.Path)
 		}
 		return
 	}
+	start := time.Now()
 	if opts.Debug {
-		log.Printf("scanning %s", root.Path)
+		log.Printf("gopathwalk: scanning %s", root.Path)
 	}
 	w := &walker{
 		root: root,
 		add:  add,
+		skip: skip,
 		opts: opts,
 	}
 	w.init()
@@ -85,15 +100,16 @@ func walkDir(root Root, add func(Root, string), opts Options) {
 	}
 
 	if opts.Debug {
-		log.Printf("scanned %s", root.Path)
+		log.Printf("gopathwalk: scanned %s in %v", root.Path, time.Since(start))
 	}
 }
 
 // walker is the callback for fastwalk.Walk.
 type walker struct {
-	root Root               // The source directory to scan.
-	add  func(Root, string) // The callback that will be invoked for every possible Go package dir.
-	opts Options            // Options passed to Walk by the user.
+	root Root                    // The source directory to scan.
+	add  func(Root, string)      // The callback that will be invoked for every possible Go package dir.
+	skip func(Root, string) bool // The callback that will be invoked for every dir. dir is skipped if it returns true.
+	opts Options                 // Options passed to Walk by the user.
 
 	ignoredDirs []os.FileInfo // The ignored directories, loaded from .goimportsignore files.
 }
@@ -151,12 +167,16 @@ func (w *walker) getIgnoredDirs(path string) []string {
 	return ignoredDirs
 }
 
-func (w *walker) shouldSkipDir(fi os.FileInfo) bool {
+func (w *walker) shouldSkipDir(fi os.FileInfo, dir string) bool {
 	for _, ignoredDir := range w.ignoredDirs {
 		if os.SameFile(fi, ignoredDir) {
 			return true
 		}
 	}
+	if w.skip != nil {
+		// Check with the user specified callback.
+		return w.skip(w.root, dir)
+	}
 	return false
 }
 
@@ -184,7 +204,7 @@ func (w *walker) walk(path string, typ os.FileMode) error {
 			return filepath.SkipDir
 		}
 		fi, err := os.Lstat(path)
-		if err == nil && w.shouldSkipDir(fi) {
+		if err == nil && w.shouldSkipDir(fi, path) {
 			return filepath.SkipDir
 		}
 		return nil
@@ -224,7 +244,7 @@ func (w *walker) shouldTraverse(dir string, fi os.FileInfo) bool {
 	if !ts.IsDir() {
 		return false
 	}
-	if w.shouldSkipDir(ts) {
+	if w.shouldSkipDir(ts, dir) {
 		return false
 	}
 	// Check for symlink loops by statting each directory component

vendor/golang.org/x/tools/internal/imports/BUILD.bazel

@@ -0,0 +1,23 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "fix.go",
+        "imports.go",
+        "mod.go",
+        "mod_cache.go",
+        "sortimports.go",
+        "zstdlib.go",
+    ],
+    importmap = "k8s.io/kops/vendor/golang.org/x/tools/internal/imports",
+    importpath = "golang.org/x/tools/internal/imports",
+    visibility = ["//vendor/golang.org/x/tools:__subpackages__"],
+    deps = [
+        "//vendor/golang.org/x/tools/go/ast/astutil:go_default_library",
+        "//vendor/golang.org/x/tools/go/packages:go_default_library",
+        "//vendor/golang.org/x/tools/internal/gopathwalk:go_default_library",
+        "//vendor/golang.org/x/tools/internal/module:go_default_library",
+        "//vendor/golang.org/x/tools/internal/semver:go_default_library",
+    ],
+)

vendor/golang.org/x/tools/internal/imports/imports.go

@@ -0,0 +1,397 @@
+// 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.
+
+//go:generate go run mkstdlib.go
+
+// Package imports implements a Go pretty-printer (like package "go/format")
+// that also adds or removes import statements as necessary.
+package imports
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/format"
+	"go/parser"
+	"go/printer"
+	"go/token"
+	"io"
+	"io/ioutil"
+	"log"
+	"regexp"
+	"strconv"
+	"strings"
+
+	"golang.org/x/tools/go/ast/astutil"
+)
+
+// Options is golang.org/x/tools/imports.Options with extra internal-only options.
+type Options struct {
+	Env *ProcessEnv // The environment to use. Note: this contains the cached module and filesystem state.
+
+	Fragment  bool // Accept fragment of a source file (no package statement)
+	AllErrors bool // Report all errors (not just the first 10 on different lines)
+
+	Comments  bool // Print comments (true if nil *Options provided)
+	TabIndent bool // Use tabs for indent (true if nil *Options provided)
+	TabWidth  int  // Tab width (8 if nil *Options provided)
+
+	FormatOnly bool // Disable the insertion and deletion of imports
+}
+
+// Process implements golang.org/x/tools/imports.Process with explicit context in env.
+func Process(filename string, src []byte, opt *Options) (formatted []byte, err error) {
+	src, opt, err = initialize(filename, src, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	fileSet := token.NewFileSet()
+	file, adjust, err := parse(fileSet, filename, src, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	if !opt.FormatOnly {
+		if err := fixImports(fileSet, file, filename, opt.Env); err != nil {
+			return nil, err
+		}
+	}
+	return formatFile(fileSet, file, src, adjust, opt)
+}
+
+// FixImports returns a list of fixes to the imports that, when applied,
+// will leave the imports in the same state as Process.
+//
+// Note that filename's directory influences which imports can be chosen,
+// so it is important that filename be accurate.
+func FixImports(filename string, src []byte, opt *Options) (fixes []*ImportFix, err error) {
+	src, opt, err = initialize(filename, src, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	fileSet := token.NewFileSet()
+	file, _, err := parse(fileSet, filename, src, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	return getFixes(fileSet, file, filename, opt.Env)
+}
+
+// ApplyFix will apply all of the fixes to the file and format it.
+func ApplyFixes(fixes []*ImportFix, filename string, src []byte, opt *Options) (formatted []byte, err error) {
+	src, opt, err = initialize(filename, src, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	fileSet := token.NewFileSet()
+	file, adjust, err := parse(fileSet, filename, src, opt)
+	if err != nil {
+		return nil, err
+	}
+
+	// Apply the fixes to the file.
+	apply(fileSet, file, fixes)
+
+	return formatFile(fileSet, file, src, adjust, opt)
+}
+
+// GetAllCandidates gets all of the standard library candidate packages to import in
+// sorted order on import path.
+func GetAllCandidates(filename string, opt *Options) (pkgs []ImportFix, err error) {
+	_, opt, err = initialize(filename, nil, opt)
+	if err != nil {
+		return nil, err
+	}
+	return getAllCandidates(filename, opt.Env)
+}
+
+// GetPackageExports returns all known packages with name pkg and their exports.
+func GetPackageExports(pkg, filename string, opt *Options) (exports []PackageExport, err error) {
+	_, opt, err = initialize(filename, nil, opt)
+	if err != nil {
+		return nil, err
+	}
+	return getPackageExports(pkg, filename, opt.Env)
+}
+
+// initialize sets the values for opt and src.
+// If they are provided, they are not changed. Otherwise opt is set to the
+// default values and src is read from the file system.
+func initialize(filename string, src []byte, opt *Options) ([]byte, *Options, error) {
+	// Use defaults if opt is nil.
+	if opt == nil {
+		opt = &Options{Comments: true, TabIndent: true, TabWidth: 8}
+	}
+
+	// Set the env if the user has not provided it.
+	if opt.Env == nil {
+		opt.Env = &ProcessEnv{
+			GOPATH: build.Default.GOPATH,
+			GOROOT: build.Default.GOROOT,
+		}
+	}
+
+	// Set the logger if the user has not provided it.
+	if opt.Env.Logf == nil {
+		opt.Env.Logf = log.Printf
+	}
+
+	if src == nil {
+		b, err := ioutil.ReadFile(filename)
+		if err != nil {
+			return nil, nil, err
+		}
+		src = b
+	}
+
+	return src, opt, nil
+}
+
+func formatFile(fileSet *token.FileSet, file *ast.File, src []byte, adjust func(orig []byte, src []byte) []byte, opt *Options) ([]byte, error) {
+	mergeImports(opt.Env, fileSet, file)
+	sortImports(opt.Env, fileSet, file)
+	imps := astutil.Imports(fileSet, file)
+	var spacesBefore []string // import paths we need spaces before
+	for _, impSection := range imps {
+		// Within each block of contiguous imports, see if any
+		// import lines are in different group numbers. If so,
+		// we'll need to put a space between them so it's
+		// compatible with gofmt.
+		lastGroup := -1
+		for _, importSpec := range impSection {
+			importPath, _ := strconv.Unquote(importSpec.Path.Value)
+			groupNum := importGroup(opt.Env, importPath)
+			if groupNum != lastGroup && lastGroup != -1 {
+				spacesBefore = append(spacesBefore, importPath)
+			}
+			lastGroup = groupNum
+		}
+
+	}
+
+	printerMode := printer.UseSpaces
+	if opt.TabIndent {
+		printerMode |= printer.TabIndent
+	}
+	printConfig := &printer.Config{Mode: printerMode, Tabwidth: opt.TabWidth}
+
+	var buf bytes.Buffer
+	err := printConfig.Fprint(&buf, fileSet, file)
+	if err != nil {
+		return nil, err
+	}
+	out := buf.Bytes()
+	if adjust != nil {
+		out = adjust(src, out)
+	}
+	if len(spacesBefore) > 0 {
+		out, err = addImportSpaces(bytes.NewReader(out), spacesBefore)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	out, err = format.Source(out)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// parse parses src, which was read from filename,
+// as a Go source file or statement list.
+func parse(fset *token.FileSet, filename string, src []byte, opt *Options) (*ast.File, func(orig, src []byte) []byte, error) {
+	parserMode := parser.Mode(0)
+	if opt.Comments {
+		parserMode |= parser.ParseComments
+	}
+	if opt.AllErrors {
+		parserMode |= parser.AllErrors
+	}
+
+	// Try as whole source file.
+	file, err := parser.ParseFile(fset, filename, src, parserMode)
+	if err == nil {
+		return file, nil, nil
+	}
+	// If the error is that the source file didn't begin with a
+	// package line and we accept fragmented input, fall through to
+	// try as a source fragment.  Stop and return on any other error.
+	if !opt.Fragment || !strings.Contains(err.Error(), "expected 'package'") {
+		return nil, nil, err
+	}
+
+	// If this is a declaration list, make it a source file
+	// by inserting a package clause.
+	// Insert using a ;, not a newline, so that parse errors are on
+	// the correct line.
+	const prefix = "package main;"
+	psrc := append([]byte(prefix), src...)
+	file, err = parser.ParseFile(fset, filename, psrc, parserMode)
+	if err == nil {
+		// Gofmt will turn the ; into a \n.
+		// Do that ourselves now and update the file contents,
+		// so that positions and line numbers are correct going forward.
+		psrc[len(prefix)-1] = '\n'
+		fset.File(file.Package).SetLinesForContent(psrc)
+
+		// If a main function exists, we will assume this is a main
+		// package and leave the file.
+		if containsMainFunc(file) {
+			return file, nil, nil
+		}
+
+		adjust := func(orig, src []byte) []byte {
+			// Remove the package clause.
+			src = src[len(prefix):]
+			return matchSpace(orig, src)
+		}
+		return file, adjust, nil
+	}
+	// If the error is that the source file didn't begin with a
+	// declaration, fall through to try as a statement list.
+	// Stop and return on any other error.
+	if !strings.Contains(err.Error(), "expected declaration") {
+		return nil, nil, err
+	}
+
+	// If this is a statement list, make it a source file
+	// by inserting a package clause and turning the list
+	// into a function body.  This handles expressions too.
+	// Insert using a ;, not a newline, so that the line numbers
+	// in fsrc match the ones in src.
+	fsrc := append(append([]byte("package p; func _() {"), src...), '}')
+	file, err = parser.ParseFile(fset, filename, fsrc, parserMode)
+	if err == nil {
+		adjust := func(orig, src []byte) []byte {
+			// Remove the wrapping.
+			// Gofmt has turned the ; into a \n\n.
+			src = src[len("package p\n\nfunc _() {"):]
+			src = src[:len(src)-len("}\n")]
+			// Gofmt has also indented the function body one level.
+			// Remove that indent.
+			src = bytes.Replace(src, []byte("\n\t"), []byte("\n"), -1)
+			return matchSpace(orig, src)
+		}
+		return file, adjust, nil
+	}
+
+	// Failed, and out of options.
+	return nil, nil, err
+}
+
+// containsMainFunc checks if a file contains a function declaration with the
+// function signature 'func main()'
+func containsMainFunc(file *ast.File) bool {
+	for _, decl := range file.Decls {
+		if f, ok := decl.(*ast.FuncDecl); ok {
+			if f.Name.Name != "main" {
+				continue
+			}
+
+			if len(f.Type.Params.List) != 0 {
+				continue
+			}
+
+			if f.Type.Results != nil && len(f.Type.Results.List) != 0 {
+				continue
+			}
+
+			return true
+		}
+	}
+
+	return false
+}
+
+func cutSpace(b []byte) (before, middle, after []byte) {
+	i := 0
+	for i < len(b) && (b[i] == ' ' || b[i] == '\t' || b[i] == '\n') {
+		i++
+	}
+	j := len(b)
+	for j > 0 && (b[j-1] == ' ' || b[j-1] == '\t' || b[j-1] == '\n') {
+		j--
+	}
+	if i <= j {
+		return b[:i], b[i:j], b[j:]
+	}
+	return nil, nil, b[j:]
+}
+
+// matchSpace reformats src to use the same space context as orig.
+// 1) If orig begins with blank lines, matchSpace inserts them at the beginning of src.
+// 2) matchSpace copies the indentation of the first non-blank line in orig
+//    to every non-blank line in src.
+// 3) matchSpace copies the trailing space from orig and uses it in place
+//   of src's trailing space.
+func matchSpace(orig []byte, src []byte) []byte {
+	before, _, after := cutSpace(orig)
+	i := bytes.LastIndex(before, []byte{'\n'})
+	before, indent := before[:i+1], before[i+1:]
+
+	_, src, _ = cutSpace(src)
+
+	var b bytes.Buffer
+	b.Write(before)
+	for len(src) > 0 {
+		line := src
+		if i := bytes.IndexByte(line, '\n'); i >= 0 {
+			line, src = line[:i+1], line[i+1:]
+		} else {
+			src = nil
+		}
+		if len(line) > 0 && line[0] != '\n' { // not blank
+			b.Write(indent)
+		}
+		b.Write(line)
+	}
+	b.Write(after)
+	return b.Bytes()
+}
+
+var impLine = regexp.MustCompile(`^\s+(?:[\w\.]+\s+)?"(.+)"`)
+
+func addImportSpaces(r io.Reader, breaks []string) ([]byte, error) {
+	var out bytes.Buffer
+	in := bufio.NewReader(r)
+	inImports := false
+	done := false
+	for {
+		s, err := in.ReadString('\n')
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, err
+		}
+
+		if !inImports && !done && strings.HasPrefix(s, "import") {
+			inImports = true
+		}
+		if inImports && (strings.HasPrefix(s, "var") ||
+			strings.HasPrefix(s, "func") ||
+			strings.HasPrefix(s, "const") ||
+			strings.HasPrefix(s, "type")) {
+			done = true
+			inImports = false
+		}
+		if inImports && len(breaks) > 0 {
+			if m := impLine.FindStringSubmatch(s); m != nil {
+				if m[1] == breaks[0] {
+					out.WriteByte('\n')
+					breaks = breaks[1:]
+				}
+			}
+		}
+
+		fmt.Fprint(&out, s)
+	}
+	return out.Bytes(), nil
+}

vendor/golang.org/x/tools/internal/imports/mod.go

@@ -0,0 +1,643 @@
+package imports
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+
+	"golang.org/x/tools/internal/gopathwalk"
+	"golang.org/x/tools/internal/module"
+	"golang.org/x/tools/internal/semver"
+)
+
+// ModuleResolver implements resolver for modules using the go command as little
+// as feasible.
+type ModuleResolver struct {
+	env            *ProcessEnv
+	moduleCacheDir string
+	dummyVendorMod *ModuleJSON // If vendoring is enabled, the pseudo-module that represents the /vendor directory.
+
+	Initialized   bool
+	Main          *ModuleJSON
+	ModsByModPath []*ModuleJSON // All modules, ordered by # of path components in module Path...
+	ModsByDir     []*ModuleJSON // ...or Dir.
+
+	// moduleCacheCache stores information about the module cache.
+	moduleCacheCache *dirInfoCache
+	otherCache       *dirInfoCache
+}
+
+type ModuleJSON struct {
+	Path      string      // module path
+	Replace   *ModuleJSON // replaced by this module
+	Main      bool        // is this the main module?
+	Dir       string      // directory holding files for this module, if any
+	GoMod     string      // path to go.mod file for this module, if any
+	GoVersion string      // go version used in module
+}
+
+func (r *ModuleResolver) init() error {
+	if r.Initialized {
+		return nil
+	}
+	mainMod, vendorEnabled, err := vendorEnabled(r.env)
+	if err != nil {
+		return err
+	}
+
+	if mainMod != nil && vendorEnabled {
+		// Vendor mode is on, so all the non-Main modules are irrelevant,
+		// and we need to search /vendor for everything.
+		r.Main = mainMod
+		r.dummyVendorMod = &ModuleJSON{
+			Path: "",
+			Dir:  filepath.Join(mainMod.Dir, "vendor"),
+		}
+		r.ModsByModPath = []*ModuleJSON{mainMod, r.dummyVendorMod}
+		r.ModsByDir = []*ModuleJSON{mainMod, r.dummyVendorMod}
+	} else {
+		// Vendor mode is off, so run go list -m ... to find everything.
+		r.initAllMods()
+	}
+
+	r.moduleCacheDir = filepath.Join(filepath.SplitList(r.env.GOPATH)[0], "/pkg/mod")
+
+	sort.Slice(r.ModsByModPath, func(i, j int) bool {
+		count := func(x int) int {
+			return strings.Count(r.ModsByModPath[x].Path, "/")
+		}
+		return count(j) < count(i) // descending order
+	})
+	sort.Slice(r.ModsByDir, func(i, j int) bool {
+		count := func(x int) int {
+			return strings.Count(r.ModsByDir[x].Dir, "/")
+		}
+		return count(j) < count(i) // descending order
+	})
+
+	if r.moduleCacheCache == nil {
+		r.moduleCacheCache = &dirInfoCache{
+			dirs: map[string]*directoryPackageInfo{},
+		}
+	}
+	if r.otherCache == nil {
+		r.otherCache = &dirInfoCache{
+			dirs: map[string]*directoryPackageInfo{},
+		}
+	}
+	r.Initialized = true
+	return nil
+}
+
+func (r *ModuleResolver) initAllMods() error {
+	stdout, err := r.env.invokeGo("list", "-m", "-json", "...")
+	if err != nil {
+		return err
+	}
+	for dec := json.NewDecoder(stdout); dec.More(); {
+		mod := &ModuleJSON{}
+		if err := dec.Decode(mod); err != nil {
+			return err
+		}
+		if mod.Dir == "" {
+			if r.env.Debug {
+				r.env.Logf("module %v has not been downloaded and will be ignored", mod.Path)
+			}
+			// Can't do anything with a module that's not downloaded.
+			continue
+		}
+		r.ModsByModPath = append(r.ModsByModPath, mod)
+		r.ModsByDir = append(r.ModsByDir, mod)
+		if mod.Main {
+			r.Main = mod
+		}
+	}
+	return nil
+}
+
+func (r *ModuleResolver) ClearForNewScan() {
+	r.otherCache = &dirInfoCache{
+		dirs: map[string]*directoryPackageInfo{},
+	}
+}
+
+func (r *ModuleResolver) ClearForNewMod() {
+	env := r.env
+	*r = ModuleResolver{
+		env: env,
+	}
+	r.init()
+}
+
+// findPackage returns the module and directory that contains the package at
+// the given import path, or returns nil, "" if no module is in scope.
+func (r *ModuleResolver) findPackage(importPath string) (*ModuleJSON, string) {
+	// This can't find packages in the stdlib, but that's harmless for all
+	// the existing code paths.
+	for _, m := range r.ModsByModPath {
+		if !strings.HasPrefix(importPath, m.Path) {
+			continue
+		}
+		pathInModule := importPath[len(m.Path):]
+		pkgDir := filepath.Join(m.Dir, pathInModule)
+		if r.dirIsNestedModule(pkgDir, m) {
+			continue
+		}
+
+		if info, ok := r.cacheLoad(pkgDir); ok {
+			if loaded, err := info.reachedStatus(nameLoaded); loaded {
+				if err != nil {
+					continue // No package in this dir.
+				}
+				return m, pkgDir
+			}
+			if scanned, err := info.reachedStatus(directoryScanned); scanned && err != nil {
+				continue // Dir is unreadable, etc.
+			}
+			// This is slightly wrong: a directory doesn't have to have an
+			// importable package to count as a package for package-to-module
+			// resolution. package main or _test files should count but
+			// don't.
+			// TODO(heschi): fix this.
+			if _, err := r.cachePackageName(info); err == nil {
+				return m, pkgDir
+			}
+		}
+
+		// Not cached. Read the filesystem.
+		pkgFiles, err := ioutil.ReadDir(pkgDir)
+		if err != nil {
+			continue
+		}
+		// A module only contains a package if it has buildable go
+		// files in that directory. If not, it could be provided by an
+		// outer module. See #29736.
+		for _, fi := range pkgFiles {
+			if ok, _ := r.env.buildContext().MatchFile(pkgDir, fi.Name()); ok {
+				return m, pkgDir
+			}
+		}
+	}
+	return nil, ""
+}
+
+func (r *ModuleResolver) cacheLoad(dir string) (directoryPackageInfo, bool) {
+	if info, ok := r.moduleCacheCache.Load(dir); ok {
+		return info, ok
+	}
+	return r.otherCache.Load(dir)
+}
+
+func (r *ModuleResolver) cacheStore(info directoryPackageInfo) {
+	if info.rootType == gopathwalk.RootModuleCache {
+		r.moduleCacheCache.Store(info.dir, info)
+	} else {
+		r.otherCache.Store(info.dir, info)
+	}
+}
+
+func (r *ModuleResolver) cacheKeys() []string {
+	return append(r.moduleCacheCache.Keys(), r.otherCache.Keys()...)
+}
+
+// cachePackageName caches the package name for a dir already in the cache.
+func (r *ModuleResolver) cachePackageName(info directoryPackageInfo) (directoryPackageInfo, error) {
+	if info.rootType == gopathwalk.RootModuleCache {
+		return r.moduleCacheCache.CachePackageName(info)
+	}
+	return r.otherCache.CachePackageName(info)
+}
+
+func (r *ModuleResolver) cacheExports(ctx context.Context, env *ProcessEnv, info directoryPackageInfo) (string, []string, error) {
+	if info.rootType == gopathwalk.RootModuleCache {
+		return r.moduleCacheCache.CacheExports(ctx, env, info)
+	}
+	return r.otherCache.CacheExports(ctx, env, info)
+}
+
+// findModuleByDir returns the module that contains dir, or nil if no such
+// module is in scope.
+func (r *ModuleResolver) findModuleByDir(dir string) *ModuleJSON {
+	// This is quite tricky and may not be correct. dir could be:
+	// - a package in the main module.
+	// - a replace target underneath the main module's directory.
+	//    - a nested module in the above.
+	// - a replace target somewhere totally random.
+	//    - a nested module in the above.
+	// - in the mod cache.
+	// - in /vendor/ in -mod=vendor mode.
+	//    - nested module? Dunno.
+	// Rumor has it that replace targets cannot contain other replace targets.
+	for _, m := range r.ModsByDir {
+		if !strings.HasPrefix(dir, m.Dir) {
+			continue
+		}
+
+		if r.dirIsNestedModule(dir, m) {
+			continue
+		}
+
+		return m
+	}
+	return nil
+}
+
+// dirIsNestedModule reports if dir is contained in a nested module underneath
+// mod, not actually in mod.
+func (r *ModuleResolver) dirIsNestedModule(dir string, mod *ModuleJSON) bool {
+	if !strings.HasPrefix(dir, mod.Dir) {
+		return false
+	}
+	if r.dirInModuleCache(dir) {
+		// Nested modules in the module cache are pruned,
+		// so it cannot be a nested module.
+		return false
+	}
+	if mod != nil && mod == r.dummyVendorMod {
+		// The /vendor pseudomodule is flattened and doesn't actually count.
+		return false
+	}
+	modDir, _ := r.modInfo(dir)
+	if modDir == "" {
+		return false
+	}
+	return modDir != mod.Dir
+}
+
+func (r *ModuleResolver) modInfo(dir string) (modDir string, modName string) {
+	readModName := func(modFile string) string {
+		modBytes, err := ioutil.ReadFile(modFile)
+		if err != nil {
+			return ""
+		}
+		return modulePath(modBytes)
+	}
+
+	if r.dirInModuleCache(dir) {
+		matches := modCacheRegexp.FindStringSubmatch(dir)
+		index := strings.Index(dir, matches[1]+"@"+matches[2])
+		modDir := filepath.Join(dir[:index], matches[1]+"@"+matches[2])
+		return modDir, readModName(filepath.Join(modDir, "go.mod"))
+	}
+	for {
+		if info, ok := r.cacheLoad(dir); ok {
+			return info.moduleDir, info.moduleName
+		}
+		f := filepath.Join(dir, "go.mod")
+		info, err := os.Stat(f)
+		if err == nil && !info.IsDir() {
+			return dir, readModName(f)
+		}
+
+		d := filepath.Dir(dir)
+		if len(d) >= len(dir) {
+			return "", "" // reached top of file system, no go.mod
+		}
+		dir = d
+	}
+}
+
+func (r *ModuleResolver) dirInModuleCache(dir string) bool {
+	if r.moduleCacheDir == "" {
+		return false
+	}
+	return strings.HasPrefix(dir, r.moduleCacheDir)
+}
+
+func (r *ModuleResolver) loadPackageNames(importPaths []string, srcDir string) (map[string]string, error) {
+	if err := r.init(); err != nil {
+		return nil, err
+	}
+	names := map[string]string{}
+	for _, path := range importPaths {
+		_, packageDir := r.findPackage(path)
+		if packageDir == "" {
+			continue
+		}
+		name, err := packageDirToName(packageDir)
+		if err != nil {
+			continue
+		}
+		names[path] = name
+	}
+	return names, nil
+}
+
+func (r *ModuleResolver) scan(_ references, loadNames bool, exclude []gopathwalk.RootType) ([]*pkg, error) {
+	if err := r.init(); err != nil {
+		return nil, err
+	}
+
+	// Walk GOROOT, GOPATH/pkg/mod, and the main module.
+	roots := []gopathwalk.Root{
+		{filepath.Join(r.env.GOROOT, "/src"), gopathwalk.RootGOROOT},
+	}
+	if r.Main != nil {
+		roots = append(roots, gopathwalk.Root{r.Main.Dir, gopathwalk.RootCurrentModule})
+	}
+	if r.dummyVendorMod != nil {
+		roots = append(roots, gopathwalk.Root{r.dummyVendorMod.Dir, gopathwalk.RootOther})
+	} else {
+		roots = append(roots, gopathwalk.Root{r.moduleCacheDir, gopathwalk.RootModuleCache})
+		// Walk replace targets, just in case they're not in any of the above.
+		for _, mod := range r.ModsByModPath {
+			if mod.Replace != nil {
+				roots = append(roots, gopathwalk.Root{mod.Dir, gopathwalk.RootOther})
+			}
+		}
+	}
+
+	roots = filterRoots(roots, exclude)
+
+	var result []*pkg
+	var mu sync.Mutex
+
+	// We assume cached directories have not changed. We can skip them and their
+	// children.
+	skip := func(root gopathwalk.Root, dir string) bool {
+		mu.Lock()
+		defer mu.Unlock()
+
+		info, ok := r.cacheLoad(dir)
+		if !ok {
+			return false
+		}
+		// This directory can be skipped as long as we have already scanned it.
+		// Packages with errors will continue to have errors, so there is no need
+		// to rescan them.
+		packageScanned, _ := info.reachedStatus(directoryScanned)
+		return packageScanned
+	}
+
+	// Add anything new to the cache. We'll process everything in it below.
+	add := func(root gopathwalk.Root, dir string) {
+		mu.Lock()
+		defer mu.Unlock()
+
+		r.cacheStore(r.scanDirForPackage(root, dir))
+	}
+
+	gopathwalk.WalkSkip(roots, add, skip, gopathwalk.Options{Debug: r.env.Debug, ModulesEnabled: true})
+
+	// Everything we already had, and everything new, is now in the cache.
+	for _, dir := range r.cacheKeys() {
+		info, ok := r.cacheLoad(dir)
+		if !ok {
+			continue
+		}
+
+		// Skip this directory if we were not able to get the package information successfully.
+		if scanned, err := info.reachedStatus(directoryScanned); !scanned || err != nil {
+			continue
+		}
+
+		// If we want package names, make sure the cache has them.
+		if loadNames {
+			var err error
+			if info, err = r.cachePackageName(info); err != nil {
+				continue
+			}
+		}
+
+		res, err := r.canonicalize(info)
+		if err != nil {
+			continue
+		}
+		result = append(result, res)
+	}
+
+	return result, nil
+}
+
+// canonicalize gets the result of canonicalizing the packages using the results
+// of initializing the resolver from 'go list -m'.
+func (r *ModuleResolver) canonicalize(info directoryPackageInfo) (*pkg, error) {
+	// Packages in GOROOT are already canonical, regardless of the std/cmd modules.
+	if info.rootType == gopathwalk.RootGOROOT {
+		return &pkg{
+			importPathShort: info.nonCanonicalImportPath,
+			dir:             info.dir,
+			packageName:     path.Base(info.nonCanonicalImportPath),
+			relevance:       0,
+		}, nil
+	}
+
+	importPath := info.nonCanonicalImportPath
+	relevance := 2
+	// Check if the directory is underneath a module that's in scope.
+	if mod := r.findModuleByDir(info.dir); mod != nil {
+		relevance = 1
+		// It is. If dir is the target of a replace directive,
+		// our guessed import path is wrong. Use the real one.
+		if mod.Dir == info.dir {
+			importPath = mod.Path
+		} else {
+			dirInMod := info.dir[len(mod.Dir)+len("/"):]
+			importPath = path.Join(mod.Path, filepath.ToSlash(dirInMod))
+		}
+	} else if info.needsReplace {
+		return nil, fmt.Errorf("package in %q is not valid without a replace statement", info.dir)
+	}
+
+	res := &pkg{
+		importPathShort: importPath,
+		dir:             info.dir,
+		packageName:     info.packageName, // may not be populated if the caller didn't ask for it
+		relevance:       relevance,
+	}
+	// We may have discovered a package that has a different version
+	// in scope already. Canonicalize to that one if possible.
+	if _, canonicalDir := r.findPackage(importPath); canonicalDir != "" {
+		res.dir = canonicalDir
+	}
+	return res, nil
+}
+
+func (r *ModuleResolver) loadExports(ctx context.Context, pkg *pkg) (string, []string, error) {
+	if err := r.init(); err != nil {
+		return "", nil, err
+	}
+	if info, ok := r.cacheLoad(pkg.dir); ok {
+		return r.cacheExports(ctx, r.env, info)
+	}
+	return loadExportsFromFiles(ctx, r.env, pkg.dir)
+}
+
+func (r *ModuleResolver) scanDirForPackage(root gopathwalk.Root, dir string) directoryPackageInfo {
+	subdir := ""
+	if dir != root.Path {
+		subdir = dir[len(root.Path)+len("/"):]
+	}
+	importPath := filepath.ToSlash(subdir)
+	if strings.HasPrefix(importPath, "vendor/") {
+		// Only enter vendor directories if they're explicitly requested as a root.
+		return directoryPackageInfo{
+			status: directoryScanned,
+			err:    fmt.Errorf("unwanted vendor directory"),
+		}
+	}
+	switch root.Type {
+	case gopathwalk.RootCurrentModule:
+		importPath = path.Join(r.Main.Path, filepath.ToSlash(subdir))
+	case gopathwalk.RootModuleCache:
+		matches := modCacheRegexp.FindStringSubmatch(subdir)
+		if len(matches) == 0 {
+			return directoryPackageInfo{
+				status: directoryScanned,
+				err:    fmt.Errorf("invalid module cache path: %v", subdir),
+			}
+		}
+		modPath, err := module.DecodePath(filepath.ToSlash(matches[1]))
+		if err != nil {
+			if r.env.Debug {
+				r.env.Logf("decoding module cache path %q: %v", subdir, err)
+			}
+			return directoryPackageInfo{
+				status: directoryScanned,
+				err:    fmt.Errorf("decoding module cache path %q: %v", subdir, err),
+			}
+		}
+		importPath = path.Join(modPath, filepath.ToSlash(matches[3]))
+	}
+
+	modDir, modName := r.modInfo(dir)
+	result := directoryPackageInfo{
+		status:                 directoryScanned,
+		dir:                    dir,
+		rootType:               root.Type,
+		nonCanonicalImportPath: importPath,
+		needsReplace:           false,
+		moduleDir:              modDir,
+		moduleName:             modName,
+	}
+	if root.Type == gopathwalk.RootGOROOT {
+		// stdlib packages are always in scope, despite the confusing go.mod
+		return result
+	}
+	// Check that this package is not obviously impossible to import.
+	if !strings.HasPrefix(importPath, modName) {
+		// The module's declared path does not match
+		// its expected path. It probably needs a
+		// replace directive we don't have.
+		result.needsReplace = true
+	}
+
+	return result
+}
+
+// modCacheRegexp splits a path in a module cache into module, module version, and package.
+var modCacheRegexp = regexp.MustCompile(`(.*)@([^/\\]*)(.*)`)
+
+var (
+	slashSlash = []byte("//")
+	moduleStr  = []byte("module")
+)
+
+// modulePath returns the module path from the gomod file text.
+// If it cannot find a module path, it returns an empty string.
+// It is tolerant of unrelated problems in the go.mod file.
+//
+// Copied from cmd/go/internal/modfile.
+func modulePath(mod []byte) string {
+	for len(mod) > 0 {
+		line := mod
+		mod = nil
+		if i := bytes.IndexByte(line, '\n'); i >= 0 {
+			line, mod = line[:i], line[i+1:]
+		}
+		if i := bytes.Index(line, slashSlash); i >= 0 {
+			line = line[:i]
+		}
+		line = bytes.TrimSpace(line)
+		if !bytes.HasPrefix(line, moduleStr) {
+			continue
+		}
+		line = line[len(moduleStr):]
+		n := len(line)
+		line = bytes.TrimSpace(line)
+		if len(line) == n || len(line) == 0 {
+			continue
+		}
+
+		if line[0] == '"' || line[0] == '`' {
+			p, err := strconv.Unquote(string(line))
+			if err != nil {
+				return "" // malformed quoted string or multiline module path
+			}
+			return p
+		}
+
+		return string(line)
+	}
+	return "" // missing module path
+}
+
+var modFlagRegexp = regexp.MustCompile(`-mod[ =](\w+)`)
+
+// vendorEnabled indicates if vendoring is enabled.
+// Inspired by setDefaultBuildMod in modload/init.go
+func vendorEnabled(env *ProcessEnv) (*ModuleJSON, bool, error) {
+	mainMod, go114, err := getMainModuleAnd114(env)
+	if err != nil {
+		return nil, false, err
+	}
+	matches := modFlagRegexp.FindStringSubmatch(env.GOFLAGS)
+	var modFlag string
+	if len(matches) != 0 {
+		modFlag = matches[1]
+	}
+	if modFlag != "" {
+		// Don't override an explicit '-mod=' argument.
+		return mainMod, modFlag == "vendor", nil
+	}
+	if mainMod == nil || !go114 {
+		return mainMod, false, nil
+	}
+	// Check 1.14's automatic vendor mode.
+	if fi, err := os.Stat(filepath.Join(mainMod.Dir, "vendor")); err == nil && fi.IsDir() {
+		if mainMod.GoVersion != "" && semver.Compare("v"+mainMod.GoVersion, "v1.14") >= 0 {
+			// The Go version is at least 1.14, and a vendor directory exists.
+			// Set -mod=vendor by default.
+			return mainMod, true, nil
+		}
+	}
+	return mainMod, false, nil
+}
+
+// getMainModuleAnd114 gets the main module's information and whether the
+// go command in use is 1.14+. This is the information needed to figure out
+// if vendoring should be enabled.
+func getMainModuleAnd114(env *ProcessEnv) (*ModuleJSON, bool, error) {
+	const format = `{{.Path}}
+{{.Dir}}
+{{.GoMod}}
+{{.GoVersion}}
+{{range context.ReleaseTags}}{{if eq . "go1.14"}}{{.}}{{end}}{{end}}
+`
+	stdout, err := env.invokeGo("list", "-m", "-f", format)
+	if err != nil {
+		return nil, false, nil
+	}
+	lines := strings.Split(stdout.String(), "\n")
+	if len(lines) < 5 {
+		return nil, false, fmt.Errorf("unexpected stdout: %q", stdout)
+	}
+	mod := &ModuleJSON{
+		Path:      lines[0],
+		Dir:       lines[1],
+		GoMod:     lines[2],
+		GoVersion: lines[3],
+		Main:      true,
+	}
+	return mod, lines[4] == "go1.14", nil
+}

vendor/golang.org/x/tools/internal/imports/mod_cache.go

@@ -0,0 +1,165 @@
+package imports
+
+import (
+	"context"
+	"fmt"
+	"sync"
+
+	"golang.org/x/tools/internal/gopathwalk"
+)
+
+// To find packages to import, the resolver needs to know about all of the
+// the packages that could be imported. This includes packages that are
+// already in modules that are in (1) the current module, (2) replace targets,
+// and (3) packages in the module cache. Packages in (1) and (2) may change over
+// time, as the client may edit the current module and locally replaced modules.
+// The module cache (which includes all of the packages in (3)) can only
+// ever be added to.
+//
+// The resolver can thus save state about packages in the module cache
+// and guarantee that this will not change over time. To obtain information
+// about new modules added to the module cache, the module cache should be
+// rescanned.
+//
+// It is OK to serve information about modules that have been deleted,
+// as they do still exist.
+// TODO(suzmue): can we share information with the caller about
+// what module needs to be downloaded to import this package?
+
+type directoryPackageStatus int
+
+const (
+	_ directoryPackageStatus = iota
+	directoryScanned
+	nameLoaded
+	exportsLoaded
+)
+
+type directoryPackageInfo struct {
+	// status indicates the extent to which this struct has been filled in.
+	status directoryPackageStatus
+	// err is non-nil when there was an error trying to reach status.
+	err error
+
+	// Set when status >= directoryScanned.
+
+	// dir is the absolute directory of this package.
+	dir      string
+	rootType gopathwalk.RootType
+	// nonCanonicalImportPath is the package's expected import path. It may
+	// not actually be importable at that path.
+	nonCanonicalImportPath string
+	// needsReplace is true if the nonCanonicalImportPath does not match the
+	// module's declared path, making it impossible to import without a
+	// replace directive.
+	needsReplace bool
+
+	// Module-related information.
+	moduleDir  string // The directory that is the module root of this dir.
+	moduleName string // The module name that contains this dir.
+
+	// Set when status >= nameLoaded.
+
+	packageName string // the package name, as declared in the source.
+
+	// Set when status >= exportsLoaded.
+
+	exports []string
+}
+
+// reachedStatus returns true when info has a status at least target and any error associated with
+// an attempt to reach target.
+func (info *directoryPackageInfo) reachedStatus(target directoryPackageStatus) (bool, error) {
+	if info.err == nil {
+		return info.status >= target, nil
+	}
+	if info.status == target {
+		return true, info.err
+	}
+	return true, nil
+}
+
+// dirInfoCache is a concurrency safe map for storing information about
+// directories that may contain packages.
+//
+// The information in this cache is built incrementally. Entries are initialized in scan.
+// No new keys should be added in any other functions, as all directories containing
+// packages are identified in scan.
+//
+// Other functions, including loadExports and findPackage, may update entries in this cache
+// as they discover new things about the directory.
+//
+// The information in the cache is not expected to change for the cache's
+// lifetime, so there is no protection against competing writes. Users should
+// take care not to hold the cache across changes to the underlying files.
+//
+// TODO(suzmue): consider other concurrency strategies and data structures (RWLocks, sync.Map, etc)
+type dirInfoCache struct {
+	mu sync.Mutex
+	// dirs stores information about packages in directories, keyed by absolute path.
+	dirs map[string]*directoryPackageInfo
+}
+
+// Store stores the package info for dir.
+func (d *dirInfoCache) Store(dir string, info directoryPackageInfo) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	stored := info // defensive copy
+	d.dirs[dir] = &stored
+}
+
+// Load returns a copy of the directoryPackageInfo for absolute directory dir.
+func (d *dirInfoCache) Load(dir string) (directoryPackageInfo, bool) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	info, ok := d.dirs[dir]
+	if !ok {
+		return directoryPackageInfo{}, false
+	}
+	return *info, true
+}
+
+// Keys returns the keys currently present in d.
+func (d *dirInfoCache) Keys() (keys []string) {
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	for key := range d.dirs {
+		keys = append(keys, key)
+	}
+	return keys
+}
+
+func (d *dirInfoCache) CachePackageName(info directoryPackageInfo) (directoryPackageInfo, error) {
+	if loaded, err := info.reachedStatus(nameLoaded); loaded {
+		return info, err
+	}
+	if scanned, err := info.reachedStatus(directoryScanned); !scanned || err != nil {
+		return info, fmt.Errorf("cannot read package name, scan error: %v", err)
+	}
+	info.packageName, info.err = packageDirToName(info.dir)
+	info.status = nameLoaded
+	d.Store(info.dir, info)
+	return info, info.err
+}
+
+func (d *dirInfoCache) CacheExports(ctx context.Context, env *ProcessEnv, info directoryPackageInfo) (string, []string, error) {
+	if reached, _ := info.reachedStatus(exportsLoaded); reached {
+		return info.packageName, info.exports, info.err
+	}
+	if reached, err := info.reachedStatus(nameLoaded); reached && err != nil {
+		return "", nil, err
+	}
+	info.packageName, info.exports, info.err = loadExportsFromFiles(ctx, env, info.dir)
+	if info.err == context.Canceled {
+		return info.packageName, info.exports, info.err
+	}
+	// The cache structure wants things to proceed linearly. We can skip a
+	// step here, but only if we succeed.
+	if info.status == nameLoaded || info.err == nil {
+		info.status = exportsLoaded
+	} else {
+		info.status = nameLoaded
+	}
+	d.Store(info.dir, info)
+	return info.packageName, info.exports, info.err
+}

vendor/golang.org/x/tools/internal/imports/sortimports.go

@@ -0,0 +1,280 @@
+// 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.
+
+// Hacked up copy of go/ast/import.go
+
+package imports
+
+import (
+	"go/ast"
+	"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(env *ProcessEnv, fset *token.FileSet, f *ast.File) {
+	for i, d := range f.Decls {
+		d, ok := d.(*ast.GenDecl)
+		if !ok || d.Tok != token.IMPORT {
+			// Not an import declaration, so we're done.
+			// Imports are always first.
+			break
+		}
+
+		if len(d.Specs) == 0 {
+			// Empty import block, remove it.
+			f.Decls = append(f.Decls[:i], f.Decls[i+1:]...)
+		}
+
+		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(env, fset, f, d.Specs[i:j])...)
+				i = j
+			}
+		}
+		specs = append(specs, sortSpecs(env, 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)
+			}
+		}
+	}
+}
+
+// mergeImports merges all the import declarations into the first one.
+// Taken from golang.org/x/tools/ast/astutil.
+func mergeImports(env *ProcessEnv, fset *token.FileSet, f *ast.File) {
+	if len(f.Decls) <= 1 {
+		return
+	}
+
+	// Merge all the import declarations into the first one.
+	var first *ast.GenDecl
+	for i := 0; i < len(f.Decls); i++ {
+		decl := f.Decls[i]
+		gen, ok := decl.(*ast.GenDecl)
+		if !ok || gen.Tok != token.IMPORT || declImports(gen, "C") {
+			continue
+		}
+		if first == nil {
+			first = gen
+			continue // Don't touch the first one.
+		}
+		// We now know there is more than one package in this import
+		// declaration. Ensure that it ends up parenthesized.
+		first.Lparen = first.Pos()
+		// Move the imports of the other import declaration to the first one.
+		for _, spec := range gen.Specs {
+			spec.(*ast.ImportSpec).Path.ValuePos = first.Pos()
+			first.Specs = append(first.Specs, spec)
+		}
+		f.Decls = append(f.Decls[:i], f.Decls[i+1:]...)
+		i--
+	}
+}
+
+// declImports reports whether gen contains an import of path.
+// Taken from golang.org/x/tools/ast/astutil.
+func declImports(gen *ast.GenDecl, path string) bool {
+	if gen.Tok != token.IMPORT {
+		return false
+	}
+	for _, spec := range gen.Specs {
+		impspec := spec.(*ast.ImportSpec)
+		if importPath(impspec) == path {
+			return true
+		}
+	}
+	return false
+}
+
+func importPath(s ast.Spec) string {
+	t, err := strconv.Unquote(s.(*ast.ImportSpec).Path.Value)
+	if err == nil {
+		return t
+	}
+	return ""
+}
+
+func importName(s ast.Spec) string {
+	n := s.(*ast.ImportSpec).Name
+	if n == nil {
+		return ""
+	}
+	return n.Name
+}
+
+func importComment(s ast.Spec) string {
+	c := s.(*ast.ImportSpec).Comment
+	if c == nil {
+		return ""
+	}
+	return c.Text()
+}
+
+// collapse indicates whether prev may be removed, leaving only next.
+func collapse(prev, next ast.Spec) bool {
+	if importPath(next) != importPath(prev) || importName(next) != importName(prev) {
+		return false
+	}
+	return prev.(*ast.ImportSpec).Comment == nil
+}
+
+type posSpan struct {
+	Start token.Pos
+	End   token.Pos
+}
+
+func sortSpecs(env *ProcessEnv, fset *token.FileSet, f *ast.File, specs []ast.Spec) []ast.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[*ast.ImportSpec][]*ast.CommentGroup{}
+	specIndex := 0
+	for _, g := range comments {
+		for specIndex+1 < len(specs) && pos[specIndex+1].Start <= g.Pos() {
+			specIndex++
+		}
+		s := specs[specIndex].(*ast.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{env, 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.(*ast.ImportSpec)
+		if s.Name != nil {
+			s.Name.NamePos = pos[i].Start
+		}
+		s.Path.ValuePos = pos[i].Start
+		s.EndPos = pos[i].End
+		nextSpecPos := pos[i].End
+
+		for _, g := range importComment[s] {
+			for _, c := range g.List {
+				c.Slash = pos[i].End
+				nextSpecPos = c.End()
+			}
+		}
+		if i < len(specs)-1 {
+			pos[i+1].Start = nextSpecPos
+			pos[i+1].End = nextSpecPos
+		}
+	}
+
+	sort.Sort(byCommentPos(comments))
+
+	// Fixup comments can insert blank lines, because import specs are on different lines.
+	// We remove those blank lines here by merging import spec to the first import spec line.
+	firstSpecLine := fset.Position(specs[0].Pos()).Line
+	for _, s := range specs[1:] {
+		p := s.Pos()
+		line := fset.File(p).Line(p)
+		for previousLine := line - 1; previousLine >= firstSpecLine; {
+			fset.File(p).MergeLine(previousLine)
+			previousLine--
+		}
+	}
+	return specs
+}
+
+type byImportSpec struct {
+	env   *ProcessEnv
+	specs []ast.Spec // slice of *ast.ImportSpec
+}
+
+func (x byImportSpec) Len() int      { return len(x.specs) }
+func (x byImportSpec) Swap(i, j int) { x.specs[i], x.specs[j] = x.specs[j], x.specs[i] }
+func (x byImportSpec) Less(i, j int) bool {
+	ipath := importPath(x.specs[i])
+	jpath := importPath(x.specs[j])
+
+	igroup := importGroup(x.env, ipath)
+	jgroup := importGroup(x.env, jpath)
+	if igroup != jgroup {
+		return igroup < jgroup
+	}
+
+	if ipath != jpath {
+		return ipath < jpath
+	}
+	iname := importName(x.specs[i])
+	jname := importName(x.specs[j])
+
+	if iname != jname {
+		return iname < jname
+	}
+	return importComment(x.specs[i]) < importComment(x.specs[j])
+}
+
+type byCommentPos []*ast.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() }

vendor/golang.org/x/tools/internal/module/BUILD.bazel

@@ -0,0 +1,10 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["module.go"],
+    importmap = "k8s.io/kops/vendor/golang.org/x/tools/internal/module",
+    importpath = "golang.org/x/tools/internal/module",
+    visibility = ["//vendor/golang.org/x/tools:__subpackages__"],
+    deps = ["//vendor/golang.org/x/tools/internal/semver:go_default_library"],
+)

vendor/golang.org/x/tools/internal/module/module.go

@@ -0,0 +1,540 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package module defines the module.Version type
+// along with support code.
+package module
+
+// IMPORTANT NOTE
+//
+// This file essentially defines the set of valid import paths for the go command.
+// There are many subtle considerations, including Unicode ambiguity,
+// security, network, and file system representations.
+//
+// This file also defines the set of valid module path and version combinations,
+// another topic with many subtle considerations.
+//
+// Changes to the semantics in this file require approval from rsc.
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"golang.org/x/tools/internal/semver"
+)
+
+// A Version is defined by a module path and version pair.
+type Version struct {
+	Path string
+
+	// Version is usually a semantic version in canonical form.
+	// There are two exceptions to this general rule.
+	// First, the top-level target of a build has no specific version
+	// and uses Version = "".
+	// Second, during MVS calculations the version "none" is used
+	// to represent the decision to take no version of a given module.
+	Version string `json:",omitempty"`
+}
+
+// Check checks that a given module path, version pair is valid.
+// In addition to the path being a valid module path
+// and the version being a valid semantic version,
+// the two must correspond.
+// For example, the path "yaml/v2" only corresponds to
+// semantic versions beginning with "v2.".
+func Check(path, version string) error {
+	if err := CheckPath(path); err != nil {
+		return err
+	}
+	if !semver.IsValid(version) {
+		return fmt.Errorf("malformed semantic version %v", version)
+	}
+	_, pathMajor, _ := SplitPathVersion(path)
+	if !MatchPathMajor(version, pathMajor) {
+		if pathMajor == "" {
+			pathMajor = "v0 or v1"
+		}
+		if pathMajor[0] == '.' { // .v1
+			pathMajor = pathMajor[1:]
+		}
+		return fmt.Errorf("mismatched module path %v and version %v (want %v)", path, version, pathMajor)
+	}
+	return nil
+}
+
+// firstPathOK reports whether r can appear in the first element of a module path.
+// The first element of the path must be an LDH domain name, at least for now.
+// To avoid case ambiguity, the domain name must be entirely lower case.
+func firstPathOK(r rune) bool {
+	return r == '-' || r == '.' ||
+		'0' <= r && r <= '9' ||
+		'a' <= r && r <= 'z'
+}
+
+// pathOK reports whether r can appear in an import path element.
+// Paths can be ASCII letters, ASCII digits, and limited ASCII punctuation: + - . _ and ~.
+// This matches what "go get" has historically recognized in import paths.
+// TODO(rsc): We would like to allow Unicode letters, but that requires additional
+// care in the safe encoding (see note below).
+func pathOK(r rune) bool {
+	if r < utf8.RuneSelf {
+		return r == '+' || r == '-' || r == '.' || r == '_' || r == '~' ||
+			'0' <= r && r <= '9' ||
+			'A' <= r && r <= 'Z' ||
+			'a' <= r && r <= 'z'
+	}
+	return false
+}
+
+// fileNameOK reports whether r can appear in a file name.
+// For now we allow all Unicode letters but otherwise limit to pathOK plus a few more punctuation characters.
+// If we expand the set of allowed characters here, we have to
+// work harder at detecting potential case-folding and normalization collisions.
+// See note about "safe encoding" below.
+func fileNameOK(r rune) bool {
+	if r < utf8.RuneSelf {
+		// Entire set of ASCII punctuation, from which we remove characters:
+		//     ! " # $ % & ' ( ) * + , - . / : ; < = > ? @ [ \ ] ^ _ ` { | } ~
+		// We disallow some shell special characters: " ' * < > ? ` |
+		// (Note that some of those are disallowed by the Windows file system as well.)
+		// We also disallow path separators / : and \ (fileNameOK is only called on path element characters).
+		// We allow spaces (U+0020) in file names.
+		const allowed = "!#$%&()+,-.=@[]^_{}~ "
+		if '0' <= r && r <= '9' || 'A' <= r && r <= 'Z' || 'a' <= r && r <= 'z' {
+			return true
+		}
+		for i := 0; i < len(allowed); i++ {
+			if rune(allowed[i]) == r {
+				return true
+			}
+		}
+		return false
+	}
+	// It may be OK to add more ASCII punctuation here, but only carefully.
+	// For example Windows disallows < > \, and macOS disallows :, so we must not allow those.
+	return unicode.IsLetter(r)
+}
+
+// CheckPath checks that a module path is valid.
+func CheckPath(path string) error {
+	if err := checkPath(path, false); err != nil {
+		return fmt.Errorf("malformed module path %q: %v", path, err)
+	}
+	i := strings.Index(path, "/")
+	if i < 0 {
+		i = len(path)
+	}
+	if i == 0 {
+		return fmt.Errorf("malformed module path %q: leading slash", path)
+	}
+	if !strings.Contains(path[:i], ".") {
+		return fmt.Errorf("malformed module path %q: missing dot in first path element", path)
+	}
+	if path[0] == '-' {
+		return fmt.Errorf("malformed module path %q: leading dash in first path element", path)
+	}
+	for _, r := range path[:i] {
+		if !firstPathOK(r) {
+			return fmt.Errorf("malformed module path %q: invalid char %q in first path element", path, r)
+		}
+	}
+	if _, _, ok := SplitPathVersion(path); !ok {
+		return fmt.Errorf("malformed module path %q: invalid version", path)
+	}
+	return nil
+}
+
+// CheckImportPath checks that an import path is valid.
+func CheckImportPath(path string) error {
+	if err := checkPath(path, false); err != nil {
+		return fmt.Errorf("malformed import path %q: %v", path, err)
+	}
+	return nil
+}
+
+// checkPath checks that a general path is valid.
+// It returns an error describing why but not mentioning path.
+// Because these checks apply to both module paths and import paths,
+// the caller is expected to add the "malformed ___ path %q: " prefix.
+// fileName indicates whether the final element of the path is a file name
+// (as opposed to a directory name).
+func checkPath(path string, fileName bool) error {
+	if !utf8.ValidString(path) {
+		return fmt.Errorf("invalid UTF-8")
+	}
+	if path == "" {
+		return fmt.Errorf("empty string")
+	}
+	if strings.Contains(path, "..") {
+		return fmt.Errorf("double dot")
+	}
+	if strings.Contains(path, "//") {
+		return fmt.Errorf("double slash")
+	}
+	if path[len(path)-1] == '/' {
+		return fmt.Errorf("trailing slash")
+	}
+	elemStart := 0
+	for i, r := range path {
+		if r == '/' {
+			if err := checkElem(path[elemStart:i], fileName); err != nil {
+				return err
+			}
+			elemStart = i + 1
+		}
+	}
+	if err := checkElem(path[elemStart:], fileName); err != nil {
+		return err
+	}
+	return nil
+}
+
+// checkElem checks whether an individual path element is valid.
+// fileName indicates whether the element is a file name (not a directory name).
+func checkElem(elem string, fileName bool) error {
+	if elem == "" {
+		return fmt.Errorf("empty path element")
+	}
+	if strings.Count(elem, ".") == len(elem) {
+		return fmt.Errorf("invalid path element %q", elem)
+	}
+	if elem[0] == '.' && !fileName {
+		return fmt.Errorf("leading dot in path element")
+	}
+	if elem[len(elem)-1] == '.' {
+		return fmt.Errorf("trailing dot in path element")
+	}
+	charOK := pathOK
+	if fileName {
+		charOK = fileNameOK
+	}
+	for _, r := range elem {
+		if !charOK(r) {
+			return fmt.Errorf("invalid char %q", r)
+		}
+	}
+
+	// Windows disallows a bunch of path elements, sadly.
+	// See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
+	short := elem
+	if i := strings.Index(short, "."); i >= 0 {
+		short = short[:i]
+	}
+	for _, bad := range badWindowsNames {
+		if strings.EqualFold(bad, short) {
+			return fmt.Errorf("disallowed path element %q", elem)
+		}
+	}
+	return nil
+}
+
+// CheckFilePath checks whether a slash-separated file path is valid.
+func CheckFilePath(path string) error {
+	if err := checkPath(path, true); err != nil {
+		return fmt.Errorf("malformed file path %q: %v", path, err)
+	}
+	return nil
+}
+
+// badWindowsNames are the reserved file path elements on Windows.
+// See https://docs.microsoft.com/en-us/windows/desktop/fileio/naming-a-file
+var badWindowsNames = []string{
+	"CON",
+	"PRN",
+	"AUX",
+	"NUL",
+	"COM1",
+	"COM2",
+	"COM3",
+	"COM4",
+	"COM5",
+	"COM6",
+	"COM7",
+	"COM8",
+	"COM9",
+	"LPT1",
+	"LPT2",
+	"LPT3",
+	"LPT4",
+	"LPT5",
+	"LPT6",
+	"LPT7",
+	"LPT8",
+	"LPT9",
+}
+
+// SplitPathVersion returns prefix and major version such that prefix+pathMajor == path
+// and version is either empty or "/vN" for N >= 2.
+// As a special case, gopkg.in paths are recognized directly;
+// they require ".vN" instead of "/vN", and for all N, not just N >= 2.
+func SplitPathVersion(path string) (prefix, pathMajor string, ok bool) {
+	if strings.HasPrefix(path, "gopkg.in/") {
+		return splitGopkgIn(path)
+	}
+
+	i := len(path)
+	dot := false
+	for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9' || path[i-1] == '.') {
+		if path[i-1] == '.' {
+			dot = true
+		}
+		i--
+	}
+	if i <= 1 || i == len(path) || path[i-1] != 'v' || path[i-2] != '/' {
+		return path, "", true
+	}
+	prefix, pathMajor = path[:i-2], path[i-2:]
+	if dot || len(pathMajor) <= 2 || pathMajor[2] == '0' || pathMajor == "/v1" {
+		return path, "", false
+	}
+	return prefix, pathMajor, true
+}
+
+// splitGopkgIn is like SplitPathVersion but only for gopkg.in paths.
+func splitGopkgIn(path string) (prefix, pathMajor string, ok bool) {
+	if !strings.HasPrefix(path, "gopkg.in/") {
+		return path, "", false
+	}
+	i := len(path)
+	if strings.HasSuffix(path, "-unstable") {
+		i -= len("-unstable")
+	}
+	for i > 0 && ('0' <= path[i-1] && path[i-1] <= '9') {
+		i--
+	}
+	if i <= 1 || path[i-1] != 'v' || path[i-2] != '.' {
+		// All gopkg.in paths must end in vN for some N.
+		return path, "", false
+	}
+	prefix, pathMajor = path[:i-2], path[i-2:]
+	if len(pathMajor) <= 2 || pathMajor[2] == '0' && pathMajor != ".v0" {
+		return path, "", false
+	}
+	return prefix, pathMajor, true
+}
+
+// MatchPathMajor reports whether the semantic version v
+// matches the path major version pathMajor.
+func MatchPathMajor(v, pathMajor string) bool {
+	if strings.HasPrefix(pathMajor, ".v") && strings.HasSuffix(pathMajor, "-unstable") {
+		pathMajor = strings.TrimSuffix(pathMajor, "-unstable")
+	}
+	if strings.HasPrefix(v, "v0.0.0-") && pathMajor == ".v1" {
+		// Allow old bug in pseudo-versions that generated v0.0.0- pseudoversion for gopkg .v1.
+		// For example, gopkg.in/yaml.v2@v2.2.1's go.mod requires gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405.
+		return true
+	}
+	m := semver.Major(v)
+	if pathMajor == "" {
+		return m == "v0" || m == "v1" || semver.Build(v) == "+incompatible"
+	}
+	return (pathMajor[0] == '/' || pathMajor[0] == '.') && m == pathMajor[1:]
+}
+
+// CanonicalVersion returns the canonical form of the version string v.
+// It is the same as semver.Canonical(v) except that it preserves the special build suffix "+incompatible".
+func CanonicalVersion(v string) string {
+	cv := semver.Canonical(v)
+	if semver.Build(v) == "+incompatible" {
+		cv += "+incompatible"
+	}
+	return cv
+}
+
+// Sort sorts the list by Path, breaking ties by comparing Versions.
+func Sort(list []Version) {
+	sort.Slice(list, func(i, j int) bool {
+		mi := list[i]
+		mj := list[j]
+		if mi.Path != mj.Path {
+			return mi.Path < mj.Path
+		}
+		// To help go.sum formatting, allow version/file.
+		// Compare semver prefix by semver rules,
+		// file by string order.
+		vi := mi.Version
+		vj := mj.Version
+		var fi, fj string
+		if k := strings.Index(vi, "/"); k >= 0 {
+			vi, fi = vi[:k], vi[k:]
+		}
+		if k := strings.Index(vj, "/"); k >= 0 {
+			vj, fj = vj[:k], vj[k:]
+		}
+		if vi != vj {
+			return semver.Compare(vi, vj) < 0
+		}
+		return fi < fj
+	})
+}
+
+// Safe encodings
+//
+// Module paths appear as substrings of file system paths
+// (in the download cache) and of web server URLs in the proxy protocol.
+// In general we cannot rely on file systems to be case-sensitive,
+// nor can we rely on web servers, since they read from file systems.
+// That is, we cannot rely on the file system to keep rsc.io/QUOTE
+// and rsc.io/quote separate. Windows and macOS don't.
+// Instead, we must never require two different casings of a file path.
+// Because we want the download cache to match the proxy protocol,
+// and because we want the proxy protocol to be possible to serve
+// from a tree of static files (which might be stored on a case-insensitive
+// file system), the proxy protocol must never require two different casings
+// of a URL path either.
+//
+// One possibility would be to make the safe encoding be the lowercase
+// hexadecimal encoding of the actual path bytes. This would avoid ever
+// needing different casings of a file path, but it would be fairly illegible
+// to most programmers when those paths appeared in the file system
+// (including in file paths in compiler errors and stack traces)
+// in web server logs, and so on. Instead, we want a safe encoding that
+// leaves most paths unaltered.
+//
+// The safe encoding is this:
+// replace every uppercase letter with an exclamation mark
+// followed by the letter's lowercase equivalent.
+//
+// For example,
+// github.com/Azure/azure-sdk-for-go ->  github.com/!azure/azure-sdk-for-go.
+// github.com/GoogleCloudPlatform/cloudsql-proxy -> github.com/!google!cloud!platform/cloudsql-proxy
+// github.com/Sirupsen/logrus -> github.com/!sirupsen/logrus.
+//
+// Import paths that avoid upper-case letters are left unchanged.
+// Note that because import paths are ASCII-only and avoid various
+// problematic punctuation (like : < and >), the safe encoding is also ASCII-only
+// and avoids the same problematic punctuation.
+//
+// Import paths have never allowed exclamation marks, so there is no
+// need to define how to encode a literal !.
+//
+// Although paths are disallowed from using Unicode (see pathOK above),
+// the eventual plan is to allow Unicode letters as well, to assume that
+// file systems and URLs are Unicode-safe (storing UTF-8), and apply
+// the !-for-uppercase convention. Note however that not all runes that
+// are different but case-fold equivalent are an upper/lower pair.
+// For example, U+004B ('K'), U+006B ('k'), and U+212A ('K' for Kelvin)
+// are considered to case-fold to each other. When we do add Unicode
+// letters, we must not assume that upper/lower are the only case-equivalent pairs.
+// Perhaps the Kelvin symbol would be disallowed entirely, for example.
+// Or perhaps it would encode as "!!k", or perhaps as "(212A)".
+//
+// Also, it would be nice to allow Unicode marks as well as letters,
+// but marks include combining marks, and then we must deal not
+// only with case folding but also normalization: both U+00E9 ('é')
+// and U+0065 U+0301 ('e' followed by combining acute accent)
+// look the same on the page and are treated by some file systems
+// as the same path. If we do allow Unicode marks in paths, there
+// must be some kind of normalization to allow only one canonical
+// encoding of any character used in an import path.
+
+// EncodePath returns the safe encoding of the given module path.
+// It fails if the module path is invalid.
+func EncodePath(path string) (encoding string, err error) {
+	if err := CheckPath(path); err != nil {
+		return "", err
+	}
+
+	return encodeString(path)
+}
+
+// EncodeVersion returns the safe encoding of the given module version.
+// Versions are allowed to be in non-semver form but must be valid file names
+// and not contain exclamation marks.
+func EncodeVersion(v string) (encoding string, err error) {
+	if err := checkElem(v, true); err != nil || strings.Contains(v, "!") {
+		return "", fmt.Errorf("disallowed version string %q", v)
+	}
+	return encodeString(v)
+}
+
+func encodeString(s string) (encoding string, err error) {
+	haveUpper := false
+	for _, r := range s {
+		if r == '!' || r >= utf8.RuneSelf {
+			// This should be disallowed by CheckPath, but diagnose anyway.
+			// The correctness of the encoding loop below depends on it.
+			return "", fmt.Errorf("internal error: inconsistency in EncodePath")
+		}
+		if 'A' <= r && r <= 'Z' {
+			haveUpper = true
+		}
+	}
+
+	if !haveUpper {
+		return s, nil
+	}
+
+	var buf []byte
+	for _, r := range s {
+		if 'A' <= r && r <= 'Z' {
+			buf = append(buf, '!', byte(r+'a'-'A'))
+		} else {
+			buf = append(buf, byte(r))
+		}
+	}
+	return string(buf), nil
+}
+
+// DecodePath returns the module path of the given safe encoding.
+// It fails if the encoding is invalid or encodes an invalid path.
+func DecodePath(encoding string) (path string, err error) {
+	path, ok := decodeString(encoding)
+	if !ok {
+		return "", fmt.Errorf("invalid module path encoding %q", encoding)
+	}
+	if err := CheckPath(path); err != nil {
+		return "", fmt.Errorf("invalid module path encoding %q: %v", encoding, err)
+	}
+	return path, nil
+}
+
+// DecodeVersion returns the version string for the given safe encoding.
+// It fails if the encoding is invalid or encodes an invalid version.
+// Versions are allowed to be in non-semver form but must be valid file names
+// and not contain exclamation marks.
+func DecodeVersion(encoding string) (v string, err error) {
+	v, ok := decodeString(encoding)
+	if !ok {
+		return "", fmt.Errorf("invalid version encoding %q", encoding)
+	}
+	if err := checkElem(v, true); err != nil {
+		return "", fmt.Errorf("disallowed version string %q", v)
+	}
+	return v, nil
+}
+
+func decodeString(encoding string) (string, bool) {
+	var buf []byte
+
+	bang := false
+	for _, r := range encoding {
+		if r >= utf8.RuneSelf {
+			return "", false
+		}
+		if bang {
+			bang = false
+			if r < 'a' || 'z' < r {
+				return "", false
+			}
+			buf = append(buf, byte(r+'A'-'a'))
+			continue
+		}
+		if r == '!' {
+			bang = true
+			continue
+		}
+		if 'A' <= r && r <= 'Z' {
+			return "", false
+		}
+		buf = append(buf, byte(r))
+	}
+	if bang {
+		return "", false
+	}
+	return string(buf), true
+}

vendor/golang.org/x/tools/internal/span/BUILD.bazel

@@ -0,0 +1,17 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "parse.go",
+        "span.go",
+        "token.go",
+        "token111.go",
+        "token112.go",
+        "uri.go",
+        "utf16.go",
+    ],
+    importmap = "k8s.io/kops/vendor/golang.org/x/tools/internal/span",
+    importpath = "golang.org/x/tools/internal/span",
+    visibility = ["//vendor/golang.org/x/tools:__subpackages__"],
+)

vendor/golang.org/x/tools/internal/span/parse.go

@@ -0,0 +1,100 @@
+// Copyright 2019 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 span
+
+import (
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+// Parse returns the location represented by the input.
+// All inputs are valid locations, as they can always be a pure filename.
+// The returned span will be normalized, and thus if printed may produce a
+// different string.
+func Parse(input string) Span {
+	// :0:0#0-0:0#0
+	valid := input
+	var hold, offset int
+	hadCol := false
+	suf := rstripSuffix(input)
+	if suf.sep == "#" {
+		offset = suf.num
+		suf = rstripSuffix(suf.remains)
+	}
+	if suf.sep == ":" {
+		valid = suf.remains
+		hold = suf.num
+		hadCol = true
+		suf = rstripSuffix(suf.remains)
+	}
+	switch {
+	case suf.sep == ":":
+		return New(NewURI(suf.remains), NewPoint(suf.num, hold, offset), Point{})
+	case suf.sep == "-":
+		// we have a span, fall out of the case to continue
+	default:
+		// separator not valid, rewind to either the : or the start
+		return New(NewURI(valid), NewPoint(hold, 0, offset), Point{})
+	}
+	// only the span form can get here
+	// at this point we still don't know what the numbers we have mean
+	// if have not yet seen a : then we might have either a line or a column depending
+	// on whether start has a column or not
+	// we build an end point and will fix it later if needed
+	end := NewPoint(suf.num, hold, offset)
+	hold, offset = 0, 0
+	suf = rstripSuffix(suf.remains)
+	if suf.sep == "#" {
+		offset = suf.num
+		suf = rstripSuffix(suf.remains)
+	}
+	if suf.sep != ":" {
+		// turns out we don't have a span after all, rewind
+		return New(NewURI(valid), end, Point{})
+	}
+	valid = suf.remains
+	hold = suf.num
+	suf = rstripSuffix(suf.remains)
+	if suf.sep != ":" {
+		// line#offset only
+		return New(NewURI(valid), NewPoint(hold, 0, offset), end)
+	}
+	// we have a column, so if end only had one number, it is also the column
+	if !hadCol {
+		end = NewPoint(suf.num, end.v.Line, end.v.Offset)
+	}
+	return New(NewURI(suf.remains), NewPoint(suf.num, hold, offset), end)
+}
+
+type suffix struct {
+	remains string
+	sep     string
+	num     int
+}
+
+func rstripSuffix(input string) suffix {
+	if len(input) == 0 {
+		return suffix{"", "", -1}
+	}
+	remains := input
+	num := -1
+	// first see if we have a number at the end
+	last := strings.LastIndexFunc(remains, func(r rune) bool { return r < '0' || r > '9' })
+	if last >= 0 && last < len(remains)-1 {
+		number, err := strconv.ParseInt(remains[last+1:], 10, 64)
+		if err == nil {
+			num = int(number)
+			remains = remains[:last+1]
+		}
+	}
+	// now see if we have a trailing separator
+	r, w := utf8.DecodeLastRuneInString(remains)
+	if r != ':' && r != '#' && r == '#' {
+		return suffix{input, "", -1}
+	}
+	remains = remains[:len(remains)-w]
+	return suffix{remains, string(r), num}
+}

vendor/golang.org/x/tools/internal/span/span.go

@@ -0,0 +1,285 @@
+// Copyright 2019 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 span contains support for representing with positions and ranges in
+// text files.
+package span
+
+import (
+	"encoding/json"
+	"fmt"
+	"path"
+)
+
+// Span represents a source code range in standardized form.
+type Span struct {
+	v span
+}
+
+// Point represents a single point within a file.
+// In general this should only be used as part of a Span, as on its own it
+// does not carry enough information.
+type Point struct {
+	v point
+}
+
+type span struct {
+	URI   URI   `json:"uri"`
+	Start point `json:"start"`
+	End   point `json:"end"`
+}
+
+type point struct {
+	Line   int `json:"line"`
+	Column int `json:"column"`
+	Offset int `json:"offset"`
+}
+
+// Invalid is a span that reports false from IsValid
+var Invalid = Span{v: span{Start: invalidPoint.v, End: invalidPoint.v}}
+
+var invalidPoint = Point{v: point{Line: 0, Column: 0, Offset: -1}}
+
+// Converter is the interface to an object that can convert between line:column
+// and offset forms for a single file.
+type Converter interface {
+	//ToPosition converts from an offset to a line:column pair.
+	ToPosition(offset int) (int, int, error)
+	//ToOffset converts from a line:column pair to an offset.
+	ToOffset(line, col int) (int, error)
+}
+
+func New(uri URI, start Point, end Point) Span {
+	s := Span{v: span{URI: uri, Start: start.v, End: end.v}}
+	s.v.clean()
+	return s
+}
+
+func NewPoint(line, col, offset int) Point {
+	p := Point{v: point{Line: line, Column: col, Offset: offset}}
+	p.v.clean()
+	return p
+}
+
+func Compare(a, b Span) int {
+	if r := CompareURI(a.URI(), b.URI()); r != 0 {
+		return r
+	}
+	if r := comparePoint(a.v.Start, b.v.Start); r != 0 {
+		return r
+	}
+	return comparePoint(a.v.End, b.v.End)
+}
+
+func ComparePoint(a, b Point) int {
+	return comparePoint(a.v, b.v)
+}
+
+func comparePoint(a, b point) int {
+	if !a.hasPosition() {
+		if a.Offset < b.Offset {
+			return -1
+		}
+		if a.Offset > b.Offset {
+			return 1
+		}
+		return 0
+	}
+	if a.Line < b.Line {
+		return -1
+	}
+	if a.Line > b.Line {
+		return 1
+	}
+	if a.Column < b.Column {
+		return -1
+	}
+	if a.Column > b.Column {
+		return 1
+	}
+	return 0
+}
+
+func (s Span) HasPosition() bool             { return s.v.Start.hasPosition() }
+func (s Span) HasOffset() bool               { return s.v.Start.hasOffset() }
+func (s Span) IsValid() bool                 { return s.v.Start.isValid() }
+func (s Span) IsPoint() bool                 { return s.v.Start == s.v.End }
+func (s Span) URI() URI                      { return s.v.URI }
+func (s Span) Start() Point                  { return Point{s.v.Start} }
+func (s Span) End() Point                    { return Point{s.v.End} }
+func (s *Span) MarshalJSON() ([]byte, error) { return json.Marshal(&s.v) }
+func (s *Span) UnmarshalJSON(b []byte) error { return json.Unmarshal(b, &s.v) }
+
+func (p Point) HasPosition() bool             { return p.v.hasPosition() }
+func (p Point) HasOffset() bool               { return p.v.hasOffset() }
+func (p Point) IsValid() bool                 { return p.v.isValid() }
+func (p *Point) MarshalJSON() ([]byte, error) { return json.Marshal(&p.v) }
+func (p *Point) UnmarshalJSON(b []byte) error { return json.Unmarshal(b, &p.v) }
+func (p Point) Line() int {
+	if !p.v.hasPosition() {
+		panic(fmt.Errorf("position not set in %v", p.v))
+	}
+	return p.v.Line
+}
+func (p Point) Column() int {
+	if !p.v.hasPosition() {
+		panic(fmt.Errorf("position not set in %v", p.v))
+	}
+	return p.v.Column
+}
+func (p Point) Offset() int {
+	if !p.v.hasOffset() {
+		panic(fmt.Errorf("offset not set in %v", p.v))
+	}
+	return p.v.Offset
+}
+
+func (p point) hasPosition() bool { return p.Line > 0 }
+func (p point) hasOffset() bool   { return p.Offset >= 0 }
+func (p point) isValid() bool     { return p.hasPosition() || p.hasOffset() }
+func (p point) isZero() bool {
+	return (p.Line == 1 && p.Column == 1) || (!p.hasPosition() && p.Offset == 0)
+}
+
+func (s *span) clean() {
+	//this presumes the points are already clean
+	if !s.End.isValid() || (s.End == point{}) {
+		s.End = s.Start
+	}
+}
+
+func (p *point) clean() {
+	if p.Line < 0 {
+		p.Line = 0
+	}
+	if p.Column <= 0 {
+		if p.Line > 0 {
+			p.Column = 1
+		} else {
+			p.Column = 0
+		}
+	}
+	if p.Offset == 0 && (p.Line > 1 || p.Column > 1) {
+		p.Offset = -1
+	}
+}
+
+// Format implements fmt.Formatter to print the Location in a standard form.
+// The format produced is one that can be read back in using Parse.
+func (s Span) Format(f fmt.State, c rune) {
+	fullForm := f.Flag('+')
+	preferOffset := f.Flag('#')
+	// we should always have a uri, simplify if it is file format
+	//TODO: make sure the end of the uri is unambiguous
+	uri := string(s.v.URI)
+	if c == 'f' {
+		uri = path.Base(uri)
+	} else if !fullForm {
+		uri = s.v.URI.Filename()
+	}
+	fmt.Fprint(f, uri)
+	if !s.IsValid() || (!fullForm && s.v.Start.isZero() && s.v.End.isZero()) {
+		return
+	}
+	// see which bits of start to write
+	printOffset := s.HasOffset() && (fullForm || preferOffset || !s.HasPosition())
+	printLine := s.HasPosition() && (fullForm || !printOffset)
+	printColumn := printLine && (fullForm || (s.v.Start.Column > 1 || s.v.End.Column > 1))
+	fmt.Fprint(f, ":")
+	if printLine {
+		fmt.Fprintf(f, "%d", s.v.Start.Line)
+	}
+	if printColumn {
+		fmt.Fprintf(f, ":%d", s.v.Start.Column)
+	}
+	if printOffset {
+		fmt.Fprintf(f, "#%d", s.v.Start.Offset)
+	}
+	// start is written, do we need end?
+	if s.IsPoint() {
+		return
+	}
+	// we don't print the line if it did not change
+	printLine = fullForm || (printLine && s.v.End.Line > s.v.Start.Line)
+	fmt.Fprint(f, "-")
+	if printLine {
+		fmt.Fprintf(f, "%d", s.v.End.Line)
+	}
+	if printColumn {
+		if printLine {
+			fmt.Fprint(f, ":")
+		}
+		fmt.Fprintf(f, "%d", s.v.End.Column)
+	}
+	if printOffset {
+		fmt.Fprintf(f, "#%d", s.v.End.Offset)
+	}
+}
+
+func (s Span) WithPosition(c Converter) (Span, error) {
+	if err := s.update(c, true, false); err != nil {
+		return Span{}, err
+	}
+	return s, nil
+}
+
+func (s Span) WithOffset(c Converter) (Span, error) {
+	if err := s.update(c, false, true); err != nil {
+		return Span{}, err
+	}
+	return s, nil
+}
+
+func (s Span) WithAll(c Converter) (Span, error) {
+	if err := s.update(c, true, true); err != nil {
+		return Span{}, err
+	}
+	return s, nil
+}
+
+func (s *Span) update(c Converter, withPos, withOffset bool) error {
+	if !s.IsValid() {
+		return fmt.Errorf("cannot add information to an invalid span")
+	}
+	if withPos && !s.HasPosition() {
+		if err := s.v.Start.updatePosition(c); err != nil {
+			return err
+		}
+		if s.v.End.Offset == s.v.Start.Offset {
+			s.v.End = s.v.Start
+		} else if err := s.v.End.updatePosition(c); err != nil {
+			return err
+		}
+	}
+	if withOffset && (!s.HasOffset() || (s.v.End.hasPosition() && !s.v.End.hasOffset())) {
+		if err := s.v.Start.updateOffset(c); err != nil {
+			return err
+		}
+		if s.v.End.Line == s.v.Start.Line && s.v.End.Column == s.v.Start.Column {
+			s.v.End.Offset = s.v.Start.Offset
+		} else if err := s.v.End.updateOffset(c); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (p *point) updatePosition(c Converter) error {
+	line, col, err := c.ToPosition(p.Offset)
+	if err != nil {
+		return err
+	}
+	p.Line = line
+	p.Column = col
+	return nil
+}
+
+func (p *point) updateOffset(c Converter) error {
+	offset, err := c.ToOffset(p.Line, p.Column)
+	if err != nil {
+		return err
+	}
+	p.Offset = offset
+	return nil
+}

vendor/golang.org/x/tools/internal/span/token.go

@@ -0,0 +1,161 @@
+// Copyright 2019 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 span
+
+import (
+	"fmt"
+	"go/token"
+)
+
+// Range represents a source code range in token.Pos form.
+// It also carries the FileSet that produced the positions, so that it is
+// self contained.
+type Range struct {
+	FileSet *token.FileSet
+	Start   token.Pos
+	End     token.Pos
+}
+
+// TokenConverter is a Converter backed by a token file set and file.
+// It uses the file set methods to work out the conversions, which
+// makes it fast and does not require the file contents.
+type TokenConverter struct {
+	fset *token.FileSet
+	file *token.File
+}
+
+// NewRange creates a new Range from a FileSet and two positions.
+// To represent a point pass a 0 as the end pos.
+func NewRange(fset *token.FileSet, start, end token.Pos) Range {
+	return Range{
+		FileSet: fset,
+		Start:   start,
+		End:     end,
+	}
+}
+
+// NewTokenConverter returns an implementation of Converter backed by a
+// token.File.
+func NewTokenConverter(fset *token.FileSet, f *token.File) *TokenConverter {
+	return &TokenConverter{fset: fset, file: f}
+}
+
+// NewContentConverter returns an implementation of Converter for the
+// given file content.
+func NewContentConverter(filename string, content []byte) *TokenConverter {
+	fset := token.NewFileSet()
+	f := fset.AddFile(filename, -1, len(content))
+	f.SetLinesForContent(content)
+	return &TokenConverter{fset: fset, file: f}
+}
+
+// IsPoint returns true if the range represents a single point.
+func (r Range) IsPoint() bool {
+	return r.Start == r.End
+}
+
+// Span converts a Range to a Span that represents the Range.
+// It will fill in all the members of the Span, calculating the line and column
+// information.
+func (r Range) Span() (Span, error) {
+	f := r.FileSet.File(r.Start)
+	if f == nil {
+		return Span{}, fmt.Errorf("file not found in FileSet")
+	}
+	s := Span{}
+	var err error
+	s.v.Start.Offset, err = offset(f, r.Start)
+	if err != nil {
+		return Span{}, err
+	}
+	if r.End.IsValid() {
+		s.v.End.Offset, err = offset(f, r.End)
+		if err != nil {
+			return Span{}, err
+		}
+	}
+	// In the presence of line directives, a single File can have sections from
+	// multiple file names.
+	filename := f.Position(r.Start).Filename
+	if r.End.IsValid() {
+		if endFilename := f.Position(r.End).Filename; filename != endFilename {
+			return Span{}, fmt.Errorf("span begins in file %q but ends in %q", filename, endFilename)
+		}
+	}
+	s.v.URI = FileURI(filename)
+
+	s.v.Start.clean()
+	s.v.End.clean()
+	s.v.clean()
+	converter := NewTokenConverter(r.FileSet, f)
+	return s.WithPosition(converter)
+}
+
+// offset is a copy of the Offset function in go/token, but with the adjustment
+// that it does not panic on invalid positions.
+func offset(f *token.File, pos token.Pos) (int, error) {
+	if int(pos) < f.Base() || int(pos) > f.Base()+f.Size() {
+		return 0, fmt.Errorf("invalid pos")
+	}
+	return int(pos) - f.Base(), nil
+}
+
+// Range converts a Span to a Range that represents the Span for the supplied
+// File.
+func (s Span) Range(converter *TokenConverter) (Range, error) {
+	s, err := s.WithOffset(converter)
+	if err != nil {
+		return Range{}, err
+	}
+	// go/token will panic if the offset is larger than the file's size,
+	// so check here to avoid panicking.
+	if s.Start().Offset() > converter.file.Size() {
+		return Range{}, fmt.Errorf("start offset %v is past the end of the file %v", s.Start(), converter.file.Size())
+	}
+	if s.End().Offset() > converter.file.Size() {
+		return Range{}, fmt.Errorf("end offset %v is past the end of the file %v", s.End(), converter.file.Size())
+	}
+	return Range{
+		FileSet: converter.fset,
+		Start:   converter.file.Pos(s.Start().Offset()),
+		End:     converter.file.Pos(s.End().Offset()),
+	}, nil
+}
+
+func (l *TokenConverter) ToPosition(offset int) (int, int, error) {
+	if offset > l.file.Size() {
+		return 0, 0, fmt.Errorf("offset %v is past the end of the file %v", offset, l.file.Size())
+	}
+	pos := l.file.Pos(offset)
+	p := l.fset.Position(pos)
+	if offset == l.file.Size() {
+		return p.Line + 1, 1, nil
+	}
+	return p.Line, p.Column, nil
+}
+
+func (l *TokenConverter) ToOffset(line, col int) (int, error) {
+	if line < 0 {
+		return -1, fmt.Errorf("line is not valid")
+	}
+	lineMax := l.file.LineCount() + 1
+	if line > lineMax {
+		return -1, fmt.Errorf("line is beyond end of file %v", lineMax)
+	} else if line == lineMax {
+		if col > 1 {
+			return -1, fmt.Errorf("column is beyond end of file")
+		}
+		// at the end of the file, allowing for a trailing eol
+		return l.file.Size(), nil
+	}
+	pos := lineStart(l.file, line)
+	if !pos.IsValid() {
+		return -1, fmt.Errorf("line is not in file")
+	}
+	// we assume that column is in bytes here, and that the first byte of a
+	// line is at column 1
+	pos += token.Pos(col - 1)
+	return offset(l.file, pos)
+}

vendor/golang.org/x/tools/internal/span/token111.go

@@ -0,0 +1,39 @@
+// Copyright 2019 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.
+
+// +build !go1.12
+
+package span
+
+import (
+	"go/token"
+)
+
+// lineStart is the pre-Go 1.12 version of (*token.File).LineStart. For Go
+// versions <= 1.11, we borrow logic from the analysisutil package.
+// TODO(rstambler): Delete this file when we no longer support Go 1.11.
+func lineStart(f *token.File, line int) token.Pos {
+	// Use binary search to find the start offset of this line.
+
+	min := 0        // inclusive
+	max := f.Size() // exclusive
+	for {
+		offset := (min + max) / 2
+		pos := f.Pos(offset)
+		posn := f.Position(pos)
+		if posn.Line == line {
+			return pos - (token.Pos(posn.Column) - 1)
+		}
+
+		if min+1 >= max {
+			return token.NoPos
+		}
+
+		if posn.Line < line {
+			min = offset
+		} else {
+			max = offset
+		}
+	}
+}

vendor/golang.org/x/tools/internal/span/token112.go

@@ -0,0 +1,16 @@
+// Copyright 2019 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.
+
+// +build go1.12
+
+package span
+
+import (
+	"go/token"
+)
+
+// TODO(rstambler): Delete this file when we no longer support Go 1.11.
+func lineStart(f *token.File, line int) token.Pos {
+	return f.LineStart(line)
+}

vendor/golang.org/x/tools/internal/span/uri.go

@@ -0,0 +1,152 @@
+// Copyright 2019 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 span
+
+import (
+	"fmt"
+	"net/url"
+	"os"
+	"path"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"unicode"
+)
+
+const fileScheme = "file"
+
+// URI represents the full URI for a file.
+type URI string
+
+// Filename returns the file path for the given URI.
+// It is an error to call this on a URI that is not a valid filename.
+func (uri URI) Filename() string {
+	filename, err := filename(uri)
+	if err != nil {
+		panic(err)
+	}
+	return filepath.FromSlash(filename)
+}
+
+func filename(uri URI) (string, error) {
+	if uri == "" {
+		return "", nil
+	}
+	u, err := url.ParseRequestURI(string(uri))
+	if err != nil {
+		return "", err
+	}
+	if u.Scheme != fileScheme {
+		return "", fmt.Errorf("only file URIs are supported, got %q from %q", u.Scheme, uri)
+	}
+	if isWindowsDriveURI(u.Path) {
+		u.Path = u.Path[1:]
+	}
+	return u.Path, nil
+}
+
+// NewURI returns a span URI for the string.
+// It will attempt to detect if the string is a file path or uri.
+func NewURI(s string) URI {
+	if u, err := url.PathUnescape(s); err == nil {
+		s = u
+	}
+	if strings.HasPrefix(s, fileScheme+"://") {
+		return URI(s)
+	}
+	return FileURI(s)
+}
+
+func CompareURI(a, b URI) int {
+	if equalURI(a, b) {
+		return 0
+	}
+	if a < b {
+		return -1
+	}
+	return 1
+}
+
+func equalURI(a, b URI) bool {
+	if a == b {
+		return true
+	}
+	// If we have the same URI basename, we may still have the same file URIs.
+	if !strings.EqualFold(path.Base(string(a)), path.Base(string(b))) {
+		return false
+	}
+	fa, err := filename(a)
+	if err != nil {
+		return false
+	}
+	fb, err := filename(b)
+	if err != nil {
+		return false
+	}
+	// Stat the files to check if they are equal.
+	infoa, err := os.Stat(filepath.FromSlash(fa))
+	if err != nil {
+		return false
+	}
+	infob, err := os.Stat(filepath.FromSlash(fb))
+	if err != nil {
+		return false
+	}
+	return os.SameFile(infoa, infob)
+}
+
+// FileURI returns a span URI for the supplied file path.
+// It will always have the file scheme.
+func FileURI(path string) URI {
+	if path == "" {
+		return ""
+	}
+	// Handle standard library paths that contain the literal "$GOROOT".
+	// TODO(rstambler): The go/packages API should allow one to determine a user's $GOROOT.
+	const prefix = "$GOROOT"
+	if len(path) >= len(prefix) && strings.EqualFold(prefix, path[:len(prefix)]) {
+		suffix := path[len(prefix):]
+		path = runtime.GOROOT() + suffix
+	}
+	if !isWindowsDrivePath(path) {
+		if abs, err := filepath.Abs(path); err == nil {
+			path = abs
+		}
+	}
+	// Check the file path again, in case it became absolute.
+	if isWindowsDrivePath(path) {
+		path = "/" + path
+	}
+	path = filepath.ToSlash(path)
+	u := url.URL{
+		Scheme: fileScheme,
+		Path:   path,
+	}
+	uri := u.String()
+	if unescaped, err := url.PathUnescape(uri); err == nil {
+		uri = unescaped
+	}
+	return URI(uri)
+}
+
+// isWindowsDrivePath returns true if the file path is of the form used by
+// Windows. We check if the path begins with a drive letter, followed by a ":".
+func isWindowsDrivePath(path string) bool {
+	if len(path) < 4 {
+		return false
+	}
+	return unicode.IsLetter(rune(path[0])) && path[1] == ':'
+}
+
+// isWindowsDriveURI returns true if the file URI is of the format used by
+// Windows URIs. The url.Parse package does not specially handle Windows paths
+// (see https://golang.org/issue/6027). We check if the URI path has
+// a drive prefix (e.g. "/C:"). If so, we trim the leading "/".
+func isWindowsDriveURI(uri string) bool {
+	if len(uri) < 4 {
+		return false
+	}
+	return uri[0] == '/' && unicode.IsLetter(rune(uri[1])) && uri[2] == ':'
+}

vendor/golang.org/x/tools/internal/span/utf16.go

@@ -0,0 +1,94 @@
+// Copyright 2019 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 span
+
+import (
+	"fmt"
+	"unicode/utf16"
+	"unicode/utf8"
+)
+
+// ToUTF16Column calculates the utf16 column expressed by the point given the
+// supplied file contents.
+// This is used to convert from the native (always in bytes) column
+// representation and the utf16 counts used by some editors.
+func ToUTF16Column(p Point, content []byte) (int, error) {
+	if content == nil {
+		return -1, fmt.Errorf("ToUTF16Column: missing content")
+	}
+	if !p.HasPosition() {
+		return -1, fmt.Errorf("ToUTF16Column: point is missing position")
+	}
+	if !p.HasOffset() {
+		return -1, fmt.Errorf("ToUTF16Column: point is missing offset")
+	}
+	offset := p.Offset()      // 0-based
+	colZero := p.Column() - 1 // 0-based
+	if colZero == 0 {
+		// 0-based column 0, so it must be chr 1
+		return 1, nil
+	} else if colZero < 0 {
+		return -1, fmt.Errorf("ToUTF16Column: column is invalid (%v)", colZero)
+	}
+	// work out the offset at the start of the line using the column
+	lineOffset := offset - colZero
+	if lineOffset < 0 || offset > len(content) {
+		return -1, fmt.Errorf("ToUTF16Column: offsets %v-%v outside file contents (%v)", lineOffset, offset, len(content))
+	}
+	// Use the offset to pick out the line start.
+	// This cannot panic: offset > len(content) and lineOffset < offset.
+	start := content[lineOffset:]
+
+	// Now, truncate down to the supplied column.
+	start = start[:colZero]
+
+	// and count the number of utf16 characters
+	// in theory we could do this by hand more efficiently...
+	return len(utf16.Encode([]rune(string(start)))) + 1, nil
+}
+
+// FromUTF16Column advances the point by the utf16 character offset given the
+// supplied line contents.
+// This is used to convert from the utf16 counts used by some editors to the
+// native (always in bytes) column representation.
+func FromUTF16Column(p Point, chr int, content []byte) (Point, error) {
+	if !p.HasOffset() {
+		return Point{}, fmt.Errorf("FromUTF16Column: point is missing offset")
+	}
+	// if chr is 1 then no adjustment needed
+	if chr <= 1 {
+		return p, nil
+	}
+	if p.Offset() >= len(content) {
+		return p, fmt.Errorf("FromUTF16Column: offset (%v) greater than length of content (%v)", p.Offset(), len(content))
+	}
+	remains := content[p.Offset():]
+	// scan forward the specified number of characters
+	for count := 1; count < chr; count++ {
+		if len(remains) <= 0 {
+			return Point{}, fmt.Errorf("FromUTF16Column: chr goes beyond the content")
+		}
+		r, w := utf8.DecodeRune(remains)
+		if r == '\n' {
+			// Per the LSP spec:
+			//
+			// > If the character value is greater than the line length it
+			// > defaults back to the line length.
+			break
+		}
+		remains = remains[w:]
+		if r >= 0x10000 {
+			// a two point rune
+			count++
+			// if we finished in a two point rune, do not advance past the first
+			if count >= chr {
+				break
+			}
+		}
+		p.v.Column += w
+		p.v.Offset += w
+	}
+	return p, nil
+}

vendor/modules.txt

@@ -510,7 +510,8 @@ golang.org/x/text/unicode/norm
 golang.org/x/text/width
 # golang.org/x/time v0.0.0-20180412165947-fbb02b2291d2
 golang.org/x/time/rate
-# golang.org/x/tools v0.0.0-20190621195816-6e04913cbbac
+# golang.org/x/tools v0.0.0-20191124021906-f5828fc9a103
+golang.org/x/tools/cmd/goimports
 golang.org/x/tools/go/analysis
 golang.org/x/tools/go/analysis/passes/inspect
 golang.org/x/tools/go/ast/astutil
@@ -525,7 +526,10 @@ golang.org/x/tools/go/types/typeutil
 golang.org/x/tools/go/vcs
 golang.org/x/tools/internal/fastwalk
 golang.org/x/tools/internal/gopathwalk
+golang.org/x/tools/internal/imports
+golang.org/x/tools/internal/module
 golang.org/x/tools/internal/semver
+golang.org/x/tools/internal/span
 # gomodules.xyz/jsonpatch/v2 v2.0.1
 gomodules.xyz/jsonpatch/v2
 # google.golang.org/api v0.0.0-20181220000619-583d854617af