git: worktree, Don't delete local untracked files when resetting worktree. Fixes go-git#53

Author: k-anshul

worktree.go

@@ -309,14 +309,15 @@ func (w *Worktree) ResetSparsely(opts *ResetOptions, dirs []string) error {
 		return err
 	}
 
+	var removedFiles []string
 	if opts.Mode == MixedReset || opts.Mode == MergeReset || opts.Mode == HardReset {
-		if err := w.resetIndex(t, dirs, opts.Files); err != nil {
+		if removedFiles, err = w.resetIndex(t, dirs, opts.Files); err != nil {
 			return err
 		}
 	}
 
 	if opts.Mode == MergeReset || opts.Mode == HardReset {
-		if err := w.resetWorktree(t, opts.Files); err != nil {
+		if err := w.resetWorktree(t, removedFiles); err != nil {
 			return err
 		}
 	}
@@ -369,23 +370,24 @@ func (w *Worktree) Reset(opts *ResetOptions) error {
 	return w.ResetSparsely(opts, nil)
 }
 
-func (w *Worktree) resetIndex(t *object.Tree, dirs []string, files []string) error {
+func (w *Worktree) resetIndex(t *object.Tree, dirs []string, files []string) ([]string, error) {
 	idx, err := w.r.Storer.Index()
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	b := newIndexBuilder(idx)
 
 	changes, err := w.diffTreeWithStaging(t, true)
 	if err != nil {
-		return err
+		return nil, err
 	}
 
+	var removedFiles []string
 	for _, ch := range changes {
 		a, err := ch.Action()
 		if err != nil {
-			return err
+			return nil, err
 		}
 
 		var name string
@@ -396,7 +398,7 @@ func (w *Worktree) resetIndex(t *object.Tree, dirs []string, files []string) err
 			name = ch.To.String()
 			e, err = t.FindEntry(name)
 			if err != nil {
-				return err
+				return nil, err
 			}
 		case merkletrie.Delete:
 			name = ch.From.String()
@@ -410,6 +412,7 @@ func (w *Worktree) resetIndex(t *object.Tree, dirs []string, files []string) err
 		}
 
 		b.Remove(name)
+		removedFiles = append(removedFiles, name)
 		if e == nil {
 			continue
 		}
@@ -428,7 +431,7 @@ func (w *Worktree) resetIndex(t *object.Tree, dirs []string, files []string) err
 		idx.SkipUnless(dirs)
 	}
 
-	return w.r.Storer.SetIndex(idx)
+	return removedFiles, w.r.Storer.SetIndex(idx)
 }
 
 func inFiles(files []string, v string) bool {
@@ -454,6 +457,11 @@ func (w *Worktree) resetWorktree(t *object.Tree, files []string) error {
 	}
 	b := newIndexBuilder(idx)
 
+	status, err := w.Status()
+	if err != nil {
+		return err
+	}
+
 	for _, ch := range changes {
 		if err := w.validChange(ch); err != nil {
 			return err
@@ -477,8 +485,13 @@ func (w *Worktree) resetWorktree(t *object.Tree, files []string) error {
 			}
 		}
 
-		if err := w.checkoutChange(ch, t, b); err != nil {
-			return err
+		// only checkout an untracked file if it is in the list of files
+		// a reset should leave untracked files alone
+		file := nameFromAction(&ch)
+		if status.File(file).Worktree != Untracked || inFiles(files, file) {
+			if err := w.checkoutChange(ch, t, b); err != nil {
+				return err
+			}
 		}
 	}
 

worktree_test.go

@@ -1138,7 +1138,16 @@ func (s *WorktreeSuite) TestResetWithUntracked() {
 
 	status, err := w.Status()
 	s.NoError(err)
-	s.True(status.IsClean())
+	for file, st := range status {
+		if file == "foo" {
+			s.Equal(Untracked, st.Worktree)
+			s.Equal(Untracked, st.Staging)
+			continue
+		}
+		if st.Worktree != Unmodified || st.Staging != Unmodified {
+			s.Fail("file %s not unmodified", file)
+		}
+	}
 }
 
 func (s *WorktreeSuite) TestResetSoft() {