fix Readdir(), Name() and New() to Walk properly

fs/fs.go

@@ -70,9 +70,14 @@ func New() (http.FileSystem, error) {
 		files["/"+zipFile.Name] = f
 	}
 	for fn := range files {
-		dn := path.Dir(fn)
-		if _, ok := files[dn]; !ok {
-			files[dn] = file{FileInfo: dirInfo{dn}, fs: fs}
+		// go up directories recursively in order to care deep directory
+		for dn := path.Dir(fn); dn != fn; {
+			if _, ok := files[dn]; !ok {
+				files[dn] = file{FileInfo: dirInfo{dn}, fs: fs}
+			} else {
+				break
+			}
+			fn, dn = dn, path.Dir(dn)
 		}
 	}
 	return fs, nil
@@ -84,7 +89,7 @@ type dirInfo struct {
 	name string
 }
 
-func (di dirInfo) Name() string       { return di.name }
+func (di dirInfo) Name() string       { return path.Base(di.name) }
 func (di dirInfo) Size() int64        { return 0 }
 func (di dirInfo) Mode() os.FileMode  { return 0755 | os.ModeDir }
 func (di dirInfo) ModTime() time.Time { return time.Time{} }
@@ -158,9 +163,18 @@ func (f *httpFile) Readdir(count int) ([]os.FileInfo, error) {
 	if !f.isDir {
 		return fis, nil
 	}
-	prefix := f.Name()
+	di, ok := f.FileInfo.(dirInfo)
+	if !ok {
+		return nil, fmt.Errorf("failed to draw dirInfo from *httpFile: %q", f.Name())
+	}
+	prefix := di.name // absolute path name
 	for fn, f := range f.file.fs.files {
-		if strings.HasPrefix(fn, prefix) && len(fn) > len(prefix) {
+		rel := strings.TrimPrefix(fn, prefix)
+		rel = strings.TrimPrefix(rel, "/")
+		// pick up only the entries just under the directory and
+		// do not follow grandchild.
+		if strings.HasPrefix(fn, prefix) && len(fn) > len(prefix) &&
+			!strings.Contains(rel, "/") {
 			fis = append(fis, f.FileInfo)
 		}
 	}

fs/fs_test.go

@@ -18,8 +18,10 @@ import (
 	"bytes"
 	"io/ioutil"
 	"os"
+	"path"
 	"path/filepath"
 	"reflect"
+	"sort"
 	"strings"
 	"sync"
 	"testing"
@@ -41,6 +43,8 @@ func TestOpen(t *testing.T) {
 	pixelGifHeader := mustFileHeader("../testdata/image/pixel.gif")
 	indexHTMLHeader := mustFileHeader("../testdata/index/index.html")
 	subdirIndexHTMLHeader := mustFileHeader("../testdata/index/sub_dir/index.html")
+	deepAHTMLHeader := mustFileHeader("../testdata/deep/a")
+	deepCHTMLHeader := mustFileHeader("../testdata/deep/aa/bb/c")
 	tests := []struct {
 		description string
 		zipData     string
@@ -115,6 +119,43 @@ func TestOpen(t *testing.T) {
 				},
 			},
 		},
+		{
+			description: "listed all sub directories in deep directory",
+			zipData:     mustZipTree("../testdata/deep"),
+			wantFiles: map[string]wantFile{
+				"/a": {
+					data:    mustReadFile("../testdata/deep/a"),
+					isDir:   false,
+					modTime: deepAHTMLHeader.ModTime(),
+					mode:    deepAHTMLHeader.Mode(),
+					name:    deepAHTMLHeader.Name,
+					size:    int64(deepAHTMLHeader.UncompressedSize64),
+				},
+				"/aa/bb/c": {
+					data:    mustReadFile("../testdata/deep/aa/bb/c"),
+					isDir:   false,
+					modTime: deepCHTMLHeader.ModTime(),
+					mode:    deepCHTMLHeader.Mode(),
+					name:    deepCHTMLHeader.Name,
+					size:    int64(deepCHTMLHeader.UncompressedSize64),
+				},
+				"/": {
+					isDir: true,
+					mode:  os.ModeDir | 0755,
+					name:  "/",
+				},
+				"/aa": {
+					isDir: true,
+					mode:  os.ModeDir | 0755,
+					name:  "/aa",
+				},
+				"/aa/bb": {
+					isDir: true,
+					mode:  os.ModeDir | 0755,
+					name:  "/aa/bb",
+				},
+			},
+		},
 	}
 	for _, tc := range tests {
 		t.Run(tc.description, func(t *testing.T) {
@@ -155,7 +196,7 @@ func TestOpen(t *testing.T) {
 				if got, want := stat.Mode(), wantFile.mode; got != want {
 					t.Errorf("Mode(%v) = %v; want %v", name, got, want)
 				}
-				if got, want := stat.Name(), wantFile.name; got != want {
+				if got, want := stat.Name(), path.Base(wantFile.name); got != want {
 					t.Errorf("Name(%v) = %v; want %v", name, got, want)
 				}
 				if got, want := stat.Size(), wantFile.size; got != want {
@@ -166,6 +207,38 @@ func TestOpen(t *testing.T) {
 	}
 }
 
+func TestWalk(t *testing.T) {
+	Register(mustZipTree("../testdata/deep"))
+	fs, err := New()
+	if err != nil {
+		t.Errorf("New() = %v", err)
+		return
+	}
+	var files []string
+	err = Walk(fs, "/", func(path string, fi os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		files = append(files, path)
+		return nil
+	})
+	if err != nil {
+		t.Errorf("Walk(fs, /) = %v", err)
+		return
+	}
+	expect := []string{
+		"/",
+		"/a",
+		"/aa",
+		"/aa/bb",
+		"/aa/bb/c",
+	}
+	sort.Strings(files)
+	if !reflect.DeepEqual(files, expect) {
+		t.Errorf("something went wrong\ngot:    %v\nexpect: %v", files, expect)
+	}
+}
+
 // Test that calling Open by many goroutines concurrently continues
 // to return the expected result.
 func TestOpen_Parallel(t *testing.T) {