Lstat method

Author: mcuadros

fs.go

@@ -31,7 +31,12 @@ type Filesystem interface {
 	Create(filename string) (File, error)
 	Open(filename string) (File, error)
 	OpenFile(filename string, flag int, perm os.FileMode) (File, error)
+	// Stat returns a FileInfo describing the named file.
 	Stat(filename string) (FileInfo, error)
+	// Lstat returns a FileInfo describing the named file. If the file is a
+	// symbolic link, the returned FileInfo describes the symbolic link. Lstat
+	// makes no attempt to follow the link.
+	Lstat(filename string) (FileInfo, error)
 	ReadDir(path string) ([]FileInfo, error)
 	TempFile(dir, prefix string) (File, error)
 	Rename(from, to string) error

memfs/memory.go

@@ -114,6 +114,19 @@ func (fs *Memory) Stat(filename string) (billy.FileInfo, error) {
 	return fi, nil
 }
 
+func (fs *Memory) Lstat(filename string) (billy.FileInfo, error) {
+	fullpath := clean(fs.Join(fs.base, filename))
+	l, ok := fs.links[fullpath]
+	if !ok {
+		return fs.Stat(filename)
+	}
+
+	return &fileInfo{
+		name: filepath.Base(l.Name),
+		mode: 0777 | os.ModeSymlink,
+	}, nil
+}
+
 // ReadDir returns a list of billy.FileInfo in the given directory.
 func (fs *Memory) ReadDir(path string) ([]billy.FileInfo, error) {
 	path = fs.resolvePath(path)

osfs/os.go

@@ -164,6 +164,11 @@ func (fs *OS) RemoveAll(path string) error {
 	return os.RemoveAll(fullpath)
 }
 
+func (fs *OS) Lstat(filename string) (billy.FileInfo, error) {
+	fullpath := fs.Join(fs.base, filename)
+	return os.Lstat(fullpath)
+}
+
 // Symlink imlements billy.Symlinker.Symlink.
 func (fs *OS) Symlink(target, link string) error {
 	target = filepath.FromSlash(target)

subdirfs/subdir.go

@@ -93,6 +93,16 @@ func (s *subdirFs) Stat(filename string) (billy.FileInfo, error) {
 	return newFileInfo(filepath.Base(fullpath), fi), nil
 }
 
+func (s *subdirFs) Lstat(filename string) (billy.FileInfo, error) {
+	fullpath := s.underlyingPath(filename)
+	fi, err := s.underlying.Lstat(fullpath)
+	if err != nil {
+		return nil, err
+	}
+
+	return newFileInfo(filepath.Base(fullpath), fi), nil
+}
+
 func (s *subdirFs) ReadDir(path string) ([]billy.FileInfo, error) {
 	prefix := s.underlyingPath(path)
 	fis, err := s.underlying.ReadDir(prefix)

test/fs_suite.go

@@ -459,6 +459,19 @@ func (s *FilesystemSuite) TestStat(c *C) {
 	c.Assert(fi.IsDir(), Equals, false)
 }
 
+func (s *FilesystemSuite) TestStatLink(c *C) {
+	WriteFile(s.FS, "foo/bar", []byte("foo"), customMode)
+	s.FS.Symlink("bar", "foo/qux")
+
+	fi, err := s.FS.Stat("foo/qux")
+	c.Assert(err, IsNil)
+	c.Assert(fi.Name(), Equals, "qux")
+	c.Assert(fi.Size(), Equals, int64(3))
+	c.Assert(fi.Mode(), Equals, customMode)
+	c.Assert(fi.ModTime().IsZero(), Equals, false)
+	c.Assert(fi.IsDir(), Equals, false)
+}
+
 func (s *FilesystemSuite) TestStatDir(c *C) {
 	s.FS.MkdirAll("foo/bar", 0644)
 
@@ -477,6 +490,30 @@ func (s *FilesystemSuite) TestStatNonExistent(c *C) {
 	c.Assert(fi, IsNil)
 }
 
+func (s *FilesystemSuite) TestLstat(c *C) {
+	WriteFile(s.FS, "foo/bar", []byte("foo"), customMode)
+
+	fi, err := s.FS.Lstat("foo/bar")
+	c.Assert(err, IsNil)
+	c.Assert(fi.Name(), Equals, "bar")
+	c.Assert(fi.Size(), Equals, int64(3))
+	c.Assert(fi.Mode()&os.ModeSymlink != 0, Equals, false)
+	c.Assert(fi.ModTime().IsZero(), Equals, false)
+	c.Assert(fi.IsDir(), Equals, false)
+}
+
+func (s *FilesystemSuite) TestLstatLink(c *C) {
+	WriteFile(s.FS, "foo/bar", []byte("fosddddaaao"), customMode)
+	s.FS.Symlink("bar", "foo/qux")
+
+	fi, err := s.FS.Lstat("foo/qux")
+	c.Assert(err, IsNil)
+	c.Assert(fi.Name(), Equals, "qux")
+	c.Assert(fi.Mode()&os.ModeSymlink != 0, Equals, true)
+	c.Assert(fi.ModTime().IsZero(), Equals, false)
+	c.Assert(fi.IsDir(), Equals, false)
+}
+
 func (s *FilesystemSuite) TestDirStat(c *C) {
 	files := []string{"foo", "bar", "qux/baz", "qux/qux"}
 	for _, name := range files {
@@ -938,8 +975,6 @@ func (s *FilesystemSuite) TestSymlinkBasic(c *C) {
 	fi, err := s.FS.Stat("link")
 	c.Assert(err, IsNil)
 	c.Assert(fi.Name(), Equals, "link")
-	c.Assert(fi.Mode()&os.ModeSymlink, Not(Equals), 0)
-	c.Assert(fi.Size(), Equals, int64(0))
 }
 
 func (s *FilesystemSuite) TestSymlinkCrossDirs(c *C) {
@@ -952,8 +987,6 @@ func (s *FilesystemSuite) TestSymlinkCrossDirs(c *C) {
 	fi, err := s.FS.Stat("bar/link")
 	c.Assert(err, IsNil)
 	c.Assert(fi.Name(), Equals, "link")
-	c.Assert(fi.Mode()&os.ModeSymlink, Not(Equals), 0)
-	c.Assert(fi.Size(), Equals, int64(0))
 }
 
 func (s *FilesystemSuite) TestSymlinkLinkToLink(c *C) {
@@ -969,8 +1002,6 @@ func (s *FilesystemSuite) TestSymlinkLinkToLink(c *C) {
 	fi, err := s.FS.Stat("linkB")
 	c.Assert(err, IsNil)
 	c.Assert(fi.Name(), Equals, "linkB")
-	c.Assert(fi.Mode()&os.ModeSymlink, Not(Equals), 0)
-	c.Assert(fi.Size(), Equals, int64(0))
 }
 
 func (s *FilesystemSuite) TestSymlinkToDir(c *C) {
@@ -983,7 +1014,6 @@ func (s *FilesystemSuite) TestSymlinkToDir(c *C) {
 	fi, err := s.FS.Stat("link")
 	c.Assert(err, IsNil)
 	c.Assert(fi.Name(), Equals, "link")
-	c.Assert(fi.Mode()&os.ModeSymlink, Not(Equals), 0)
 	c.Assert(fi.IsDir(), Equals, true)
 }
 

tmpoverlayfs/tmpfs.go

@@ -152,6 +152,14 @@ func (t *tmpFs) Stat(path string) (billy.FileInfo, error) {
 	return t.fs.Stat(path)
 }
 
+func (t *tmpFs) Lstat(path string) (billy.FileInfo, error) {
+	if t.isTmpFile(path) {
+		return t.tmp.Lstat(path)
+	}
+
+	return t.fs.Lstat(path)
+}
+
 func (t *tmpFs) isTmpFile(p string) bool {
 	p = path.Clean(p)
 	_, ok := t.tempFiles[p]