Improving / Exposing Git-Trees related features for Git-Trees API. (go-gitea#123)

* Exposed TreeEntry.mode, changed EntryMode to hex.

* Added reference parsing (HEAD, HEAD~1, etc) for trees

* Added missing description

* Added Tree.ListEntriesRecursive() - utilizes the git ls-tree -r command

Author: Kasi-R

repo_tree.go

@@ -18,6 +18,15 @@ func (repo *Repository) getTree(id SHA1) (*Tree, error) {
 
 // GetTree find the tree object in the repository.
 func (repo *Repository) GetTree(idStr string) (*Tree, error) {
+	if len(idStr) != 40 {
+		res, err := NewCommand("rev-parse", idStr).RunInDir(repo.Path)
+		if err != nil {
+			return nil, err;
+		}
+		if len(res) > 0 {
+			idStr = res[:len(res)-1]
+		}
+	}
 	id, err := NewIDFromString(idStr)
 	if err != nil {
 		return nil, err

tree.go

@@ -70,3 +70,17 @@ func (t *Tree) ListEntries() (Entries, error) {
 	t.entries, err = parseTreeEntries(stdout, t)
 	return t.entries, err
 }
+
+// ListEntriesRecursive returns all entries of current tree recursively including all subtrees
+func (t *Tree) ListEntriesRecursive() (Entries, error) {
+	if t.entriesParsed {
+		return t.entries, nil
+	}
+	stdout, err := NewCommand("ls-tree", "-t", "-r", t.ID.String()).RunInDirBytes(t.repo.Path)
+
+	if err != nil {
+		return nil, err
+	}
+	t.entries, err = parseTreeEntries(stdout, t)
+	return t.entries, err
+}

tree_entry.go

@@ -18,15 +18,15 @@ type EntryMode int
 // one of these.
 const (
 	// EntryModeBlob
-	EntryModeBlob EntryMode = 0100644
+	EntryModeBlob EntryMode = 0x0100644
 	// EntryModeExec
-	EntryModeExec EntryMode = 0100755
+	EntryModeExec EntryMode = 0x0100755
 	// EntryModeSymlink
-	EntryModeSymlink EntryMode = 0120000
+	EntryModeSymlink EntryMode = 0x0120000
 	// EntryModeCommit
-	EntryModeCommit EntryMode = 0160000
+	EntryModeCommit EntryMode = 0x0160000
 	// EntryModeTree
-	EntryModeTree EntryMode = 0040000
+	EntryModeTree EntryMode = 0x0040000
 )
 
 // TreeEntry the leaf in the git tree
@@ -50,6 +50,11 @@ func (te *TreeEntry) Name() string {
 	return te.name
 }
 
+// Mode returns the mode of the entry
+func (te *TreeEntry) Mode() EntryMode {
+	return te.mode
+}
+
 // Size returns the size of the entry
 func (te *TreeEntry) Size() int64 {
 	if te.IsDir() {