Update github.com/mjibson/esc (#515)

* Update github.com/mjibson/esc

* Update github.com/mjibson/esc
* Fix generate.go to new signature for esc.Run

* Internal: Upgrade to lastest "esc"

vendor/github.com/mjibson/esc/embed/embed.go

@@ -6,6 +6,7 @@ import (
 	"compress/gzip"
 	"encoding/base64"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	"path"
@@ -15,6 +16,9 @@ import (
 	"strconv"
 	"strings"
 	"text/template"
+
+	"github.com/pkg/errors"
+	"golang.org/x/tools/imports"
 )
 
 // Config contains all information needed to run esc.
@@ -36,6 +40,8 @@ type Config struct {
 	Private bool
 	// NoCompression, if true, stores the files without compression.
 	NoCompression bool
+	// Invocation, if set, is added to the invocation string in the generated template.
+	Invocation string
 
 	// Files is the list of files or directories to embed.
 	Files []string
@@ -43,20 +49,36 @@ type Config struct {
 
 var modTime *int64
 
-type headerTemplateParams struct {
+var tmpl = template.Must(template.New("").Parse(fileTemplate))
+
+type templateParams struct {
 	Invocation     string
 	PackageName    string
 	FunctionPrefix string
+	Files          []*_escFile
+	Dirs           []*_escDir
 }
 
 type _escFile struct {
-	data     []byte
-	local    string
+	Name       string
+	BaseName   string
+	Data       []byte
+	Local      string
+	ModTime    int64
+	Compressed string
+
 	fileinfo os.FileInfo
 }
 
+type _escDir struct {
+	Name           string
+	BaseName       string
+	Local          string
+	ChildFileNames []string
+}
+
 // Run executes a Config.
-func Run(conf *Config) error {
+func Run(conf *Config, out io.Writer) error {
 	var err error
 	if conf.ModTime != "" {
 		i, err := strconv.ParseInt(conf.ModTime, 10, 64)
@@ -65,8 +87,9 @@ func Run(conf *Config) error {
 		}
 		modTime = &i
 	}
-	var fnames, dirnames []string
-	content := make(map[string]_escFile)
+
+	alreadyPrepared := make(map[string]bool, 10)
+	escFiles := make([]*_escFile, 0, 10)
 	prefix := filepath.ToSlash(conf.Prefix)
 	var ignoreRegexp *regexp.Regexp
 	if conf.Ignore != "" {
@@ -82,6 +105,11 @@ func Run(conf *Config) error {
 			return err
 		}
 	}
+	gzipLevel := gzip.BestCompression
+	if conf.NoCompression {
+		gzipLevel = gzip.NoCompression
+	}
+	directories := make([]*_escDir, 0, 10)
 	for _, base := range conf.Files {
 		files := []string{base}
 		for len(files) > 0 {
@@ -98,146 +126,126 @@ func Run(conf *Config) error {
 			if err != nil {
 				return err
 			}
+			fpath := filepath.ToSlash(fname)
+			n := canonicFileName(fname, prefix)
 			if fi.IsDir() {
 				fis, err := f.Readdir(0)
 				if err != nil {
 					return err
 				}
-				for _, fi := range fis {
-					files = append(files, filepath.Join(fname, fi.Name()))
+				dir := &_escDir{
+					Name:           n,
+					BaseName:       path.Base(n),
+					Local:          fpath,
+					ChildFileNames: make([]string, 0, len(fis)),
 				}
+				for _, fi := range fis {
+					childFName := filepath.Join(fname, fi.Name())
+					files = append(files, childFName)
+					if ignoreRegexp != nil && ignoreRegexp.MatchString(childFName) {
+						continue
+					}
+					if includeRegexp == nil || includeRegexp.MatchString(childFName) {
+						dir.ChildFileNames = append(dir.ChildFileNames, canonicFileName(filepath.Join(fname, fi.Name()), prefix))
+					}
+				}
+				sort.Strings(dir.ChildFileNames)
+				directories = append(directories, dir)
 			} else if includeRegexp == nil || includeRegexp.MatchString(fname) {
 				b, err := ioutil.ReadAll(f)
 				if err != nil {
+					return errors.Wrap(err, "readAll return err")
+				}
+				if alreadyPrepared[n] {
+					return fmt.Errorf("%s, %s: duplicate Name after prefix removal", n, fpath)
+				}
+				escFile := &_escFile{
+					Name:     n,
+					BaseName: path.Base(n),
+					Data:     b,
+					Local:    fpath,
+					fileinfo: fi,
+					ModTime:  fi.ModTime().Unix(),
+				}
+				if modTime != nil {
+					escFile.ModTime = *modTime
+				}
+				if err := escFile.fillCompressed(gzipLevel); err != nil {
 					return err
 				}
-				fpath := filepath.ToSlash(fname)
-				n := strings.TrimPrefix(fpath, prefix)
-				n = path.Join("/", n)
-				if _, ok := content[n]; ok {
-					return fmt.Errorf("%s, %s: duplicate name after prefix removal", n, fpath)
-				}
-				content[n] = _escFile{data: b, local: fpath, fileinfo: fi}
-				fnames = append(fnames, n)
+				escFiles = append(escFiles, escFile)
+				alreadyPrepared[n] = true
 			}
 			f.Close()
 		}
 	}
-	sort.Strings(fnames)
-	w := new(bytes.Buffer)
-	headerText, err := header(conf.Package, !(conf.Private))
-	if nil != err {
-		return fmt.Errorf("failed to expand autogenerated code: %s", err)
+
+	sort.Slice(escFiles, func(i, j int) bool { return strings.Compare(escFiles[i].Name, escFiles[j].Name) == -1 })
+	sort.Slice(directories, func(i, j int) bool { return strings.Compare(directories[i].Name, directories[j].Name) == -1 })
+
+	functionPrefix := ""
+	if conf.Private {
+		functionPrefix = "_esc"
 	}
-	if _, err := w.Write(headerText); err != nil {
-		return fmt.Errorf("failed to write output: %s", err)
-	}
-	dirs := map[string]bool{"/": true}
-	gzipLevel := gzip.BestCompression
-	if conf.NoCompression {
-		gzipLevel = gzip.NoCompression
-	}
-	for _, fname := range fnames {
-		f := content[fname]
-		for b := path.Dir(fname); b != "/"; b = path.Dir(b) {
-			dirs[b] = true
-		}
-		var buf bytes.Buffer
-		gw, err := gzip.NewWriterLevel(&buf, gzipLevel)
-		if err != nil {
-			return err
-		}
-		if _, err := gw.Write(f.data); err != nil {
-			return err
-		}
-		if err := gw.Close(); err != nil {
-			return err
-		}
-		t := f.fileinfo.ModTime().Unix()
-		if modTime != nil {
-			t = *modTime
-		}
-		fmt.Fprintf(w, `
-	%q: {
-		local:   %q,
-		size:    %v,
-		modtime: %v,
-		compressed: %s,
-	},%s`, fname, f.local, len(f.data), t, segment(&buf), "\n")
-	}
-	for d := range dirs {
-		dirnames = append(dirnames, d)
-	}
-	sort.Strings(dirnames)
-	for _, dir := range dirnames {
-		local := path.Join(prefix, dir)
-		if len(local) == 0 {
-			local = "."
-		}
-		if local[0] == '/' {
-			// Read dirs relative to the go proc's cwd vs system's
-			// fs root.
-			local = local[1:]
-		}
-		fmt.Fprintf(w, `
-	%q: {
-		isDir: true,
-		local: %q,
-	},%s`, dir, local, "\n")
-	}
-	w.WriteString(footer)
-	out := os.Stdout
+
+	buf := bytes.NewBuffer(nil)
+	tmpl.Execute(buf, templateParams{
+		Invocation:     conf.Invocation,
+		PackageName:    conf.Package,
+		FunctionPrefix: functionPrefix,
+		Files:          escFiles,
+		Dirs:           directories,
+	})
+
+	fakeOutFileName := "static.go"
 	if conf.OutputFile != "" {
-		if out, err = os.Create(conf.OutputFile); err != nil {
-			return err
-		}
+		fakeOutFileName = conf.OutputFile
 	}
-	if _, err := w.WriteTo(out); err != nil {
-		return err
-	}
-	if conf.OutputFile != "" {
-		return out.Close()
+
+	data, err := imports.Process(fakeOutFileName, buf.Bytes(), nil)
+	if err != nil {
+		return errors.Wrap(err, "imports.Process return error")
 	}
+
+	fmt.Fprint(out, string(data))
+
 	return nil
 }
 
-func segment(s *bytes.Buffer) string {
+func canonicFileName(fname, prefix string) string {
+	fpath := filepath.ToSlash(fname)
+	return path.Join("/", strings.TrimPrefix(fpath, prefix))
+}
+
+func (f *_escFile) fillCompressed(gzipLevel int) error {
+	var buf bytes.Buffer
+	gw, err := gzip.NewWriterLevel(&buf, gzipLevel)
+	if err != nil {
+		return err
+	}
+	if _, err := gw.Write(f.Data); err != nil {
+		return err
+	}
+	if err := gw.Close(); err != nil {
+		return err
+	}
 	var b bytes.Buffer
 	b64 := base64.NewEncoder(base64.StdEncoding, &b)
-	b64.Write(s.Bytes())
+	b64.Write(buf.Bytes())
 	b64.Close()
-	res := "`\n"
+	res := "\n"
 	chunk := make([]byte, 80)
 	for n, _ := b.Read(chunk); n > 0; n, _ = b.Read(chunk) {
 		res += string(chunk[0:n]) + "\n"
 	}
-	return res + "`"
-}
 
-func header(packageName string, enableExports bool) ([]byte, error) {
-	functionPrefix := ""
-	if !enableExports {
-		functionPrefix = "_esc"
-	}
-	headerParams := headerTemplateParams{
-		Invocation:     strings.Join(os.Args[1:], " "),
-		PackageName:    packageName,
-		FunctionPrefix: functionPrefix,
-	}
-	tmpl, err := template.New("").Parse(headerTemplate)
-	if nil != err {
-		return nil, err
-	}
-	var b bytes.Buffer
-	err = tmpl.Execute(&b, headerParams)
-	if nil != err {
-		return nil, err
-	}
-	return b.Bytes(), nil
+	f.Compressed = res
+	return nil
+
 }
 
 const (
-	headerTemplate = `// Code generated by "esc {{.Invocation}}"; DO NOT EDIT.
+	fileTemplate = `// Code generated by "esc{{with .Invocation}} {{.}}{{end}}"; DO NOT EDIT.
 
 package {{.PackageName}}
 
@@ -339,9 +347,27 @@ func (f *_escFile) Close() error {
 }
 
 func (f *_escFile) Readdir(count int) ([]os.FileInfo, error) {
-	return nil, nil
+	if !f.isDir {
+		return nil, fmt.Errorf(" escFile.Readdir: '%s' is not directory", f.name)
+	}
+
+	fis, ok := _escDirs[f.local]
+	if !ok {
+		return nil, fmt.Errorf(" escFile.Readdir: '%s' is directory, but we have no info about content of this dir, local=%s", f.name, f.local)
+	}
+	limit := count
+	if count <= 0 || limit > len(fis) {
+		limit = len(fis)
+	}
+
+	if len(fis) == 0 && count > 0 {
+		return nil, io.EOF
+	}
+
+	return fis[0:limit], nil
 }
 
+
 func (f *_escFile) Stat() (os.FileInfo, error) {
 	return f, nil
 }
@@ -428,7 +454,33 @@ func {{.FunctionPrefix}}FSMustString(useLocal bool, name string) string {
 }
 
 var _escData = map[string]*_escFile{
-`
-	footer = `}
+{{ range .Files }}
+	"{{ .Name }}": {
+		name:    "{{ .BaseName }}",
+		local:   "{{ .Local }}",
+		size:    {{ .Data | len  }},
+		modtime: {{ .ModTime }},
+		compressed: ` + "`" + `{{ .Compressed }}` + "`" + `,
+	},
+{{ end -}}
+{{ range .Dirs }}
+	"{{ .Name }}": {
+		name:  "{{ .BaseName }}",
+		local: ` + "`" + `{{ .Local }}` + "`" + `,
+		isDir: true,
+	},
+  {{ end }}
+}
+
+var _escDirs = map[string][]os.FileInfo{
+  {{ range .Dirs }}
+	"{{ .Local }}": {
+		{{ range .ChildFileNames -}}
+		_escData["{{.}}"],
+		{{ end }}
+	},
+  {{ end }}
+}
+
 `
 )