vfs: fix renaming a directory

Before this change, renaming a directory d failed to rename its key in
d.parent.items, which caused trouble later when doing Dir.Stat on a
subdirectory. This change fixes the issue.

vfs/dir.go

@@ -371,7 +371,9 @@ func (d *Dir) renameTree(dirPath string) {
 	// Make sure the path is correct for each node
 	if d.path != dirPath {
 		fs.Debugf(d.path, "Renaming to %q", dirPath)
+		delete(d.parent.items, name(d.path))
 		d.path = dirPath
+		d.parent.items[name(d.path)] = d
 		d.entry = fs.NewDirCopy(context.TODO(), d.entry).SetRemote(dirPath)
 	}
 
@@ -404,6 +406,8 @@ func (d *Dir) rename(newParent *Dir, fsDir fs.Directory) {
 	d.entry = fsDir
 	d.path = fsDir.Remote()
 	newPath := d.path
+	delete(d.parent.items, name(oldPath))
+	d.parent.items[name(d.path)] = d
 	d.read = time.Time{}
 	d.mu.Unlock()
 
@@ -418,6 +422,15 @@ func (d *Dir) rename(newParent *Dir, fsDir fs.Directory) {
 	}
 }
 
+// convert path to name
+func name(p string) string {
+	p = path.Base(p)
+	if p == "." {
+		p = "/"
+	}
+	return p
+}
+
 // addObject adds a new object or directory to the directory
 //
 // The name passed in is marked as virtual as it hasn't been read from a remote

vfs/dir_test.go

@@ -589,6 +589,19 @@ func TestDirRename(t *testing.T) {
 	vfs.Opt.ReadOnly = true
 	err = dir.Rename("potato", "tuba", dir)
 	assert.Equal(t, EROFS, err)
+
+	// Rename a dir, check that key was correctly renamed in dir.parent.items
+	vfs.Opt.ReadOnly = false
+	_, ok := dir.parent.items["dir2"]
+	assert.True(t, ok, "dir.parent.items should have 'dir2' key before rename")
+	_, ok = dir.parent.items["dir3"]
+	assert.False(t, ok, "dir.parent.items should not have 'dir3' key before rename")
+	dir.renameTree("dir3") // rename dir2 to dir3
+	_, ok = dir.parent.items["dir2"]
+	assert.False(t, ok, "dir.parent.items should not have 'dir2' key after rename")
+	d, ok := dir.parent.items["dir3"]
+	assert.True(t, ok, fmt.Sprintf("expected to find 'dir3' key in dir.parent.items after rename, got %v", dir.parent.items))
+	assert.Equal(t, dir, d, `expected renamed dir to match value of dir.parent.items["dir3"]`)
 }
 
 func TestDirStructSize(t *testing.T) {