support the open-icon of folder (#34168) (#34896)

Backport #34168 by @kerwin612

Co-authored-by: Kerwin Bryant <kerwin612@qq.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/git/tree_entry_mode.go

@@ -30,6 +30,31 @@ func (e EntryMode) String() string {
 	return strconv.FormatInt(int64(e), 8)
 }
 
+// IsSubModule if the entry is a sub module
+func (e EntryMode) IsSubModule() bool {
+	return e == EntryModeCommit
+}
+
+// IsDir if the entry is a sub dir
+func (e EntryMode) IsDir() bool {
+	return e == EntryModeTree
+}
+
+// IsLink if the entry is a symlink
+func (e EntryMode) IsLink() bool {
+	return e == EntryModeSymlink
+}
+
+// IsRegular if the entry is a regular file
+func (e EntryMode) IsRegular() bool {
+	return e == EntryModeBlob
+}
+
+// IsExecutable if the entry is an executable file (not necessarily binary)
+func (e EntryMode) IsExecutable() bool {
+	return e == EntryModeExec
+}
+
 func ParseEntryMode(mode string) (EntryMode, error) {
 	switch mode {
 	case "000000":