fix: git grep bare repositories

Perform grep on `*Repository` instead of `*Worktree`.

Fixes: #68

options.go

@@ -642,15 +642,21 @@ var (
 )
 
 // Validate validates the fields and sets the default values.
+//
+// TODO: deprecate in favor of Validate(r *Repository) in v6.
 func (o *GrepOptions) Validate(w *Worktree) error {
+	return o.validate(w.r)
+}
+
+func (o *GrepOptions) validate(r *Repository) error {
 	if !o.CommitHash.IsZero() && o.ReferenceName != "" {
 		return ErrHashOrReference
 	}
 
 	// If none of CommitHash and ReferenceName are provided, set commit hash of
 	// the repository's head.
 	if o.CommitHash.IsZero() && o.ReferenceName == "" {
-		ref, err := w.r.Head()
+		ref, err := r.Head()
 		if err != nil {
 			return err
 		}

worktree.go

@@ -290,7 +290,7 @@ func (w *Worktree) ResetSparsely(opts *ResetOptions, dirs []string) error {
 		return nil
 	}
 
-	t, err := w.getTreeFromCommitHash(opts.Commit)
+	t, err := w.r.getTreeFromCommitHash(opts.Commit)
 	if err != nil {
 		return err
 	}
@@ -633,8 +633,8 @@ func (w *Worktree) addIndexFromFile(name string, h plumbing.Hash, idx *indexBuil
 	return nil
 }
 
-func (w *Worktree) getTreeFromCommitHash(commit plumbing.Hash) (*object.Tree, error) {
-	c, err := w.r.CommitObject(commit)
+func (r *Repository) getTreeFromCommitHash(commit plumbing.Hash) (*object.Tree, error) {
+	c, err := r.CommitObject(commit)
 	if err != nil {
 		return nil, err
 	}
@@ -802,9 +802,9 @@ func (gr GrepResult) String() string {
 	return fmt.Sprintf("%s:%s:%d:%s", gr.TreeName, gr.FileName, gr.LineNumber, gr.Content)
 }
 
-// Grep performs grep on a worktree.
-func (w *Worktree) Grep(opts *GrepOptions) ([]GrepResult, error) {
-	if err := opts.Validate(w); err != nil {
+// Grep performs grep on a repository.
+func (r *Repository) Grep(opts *GrepOptions) ([]GrepResult, error) {
+	if err := opts.validate(r); err != nil {
 		return nil, err
 	}
 
@@ -814,7 +814,7 @@ func (w *Worktree) Grep(opts *GrepOptions) ([]GrepResult, error) {
 	var treeName string
 
 	if opts.ReferenceName != "" {
-		ref, err := w.r.Reference(opts.ReferenceName, true)
+		ref, err := r.Reference(opts.ReferenceName, true)
 		if err != nil {
 			return nil, err
 		}
@@ -827,7 +827,7 @@ func (w *Worktree) Grep(opts *GrepOptions) ([]GrepResult, error) {
 
 	// Obtain a tree from the commit hash and get a tracked files iterator from
 	// the tree.
-	tree, err := w.getTreeFromCommitHash(commitHash)
+	tree, err := r.getTreeFromCommitHash(commitHash)
 	if err != nil {
 		return nil, err
 	}
@@ -836,6 +836,11 @@ func (w *Worktree) Grep(opts *GrepOptions) ([]GrepResult, error) {
 	return findMatchInFiles(fileiter, treeName, opts)
 }
 
+// Grep performs grep on a worktree.
+func (w *Worktree) Grep(opts *GrepOptions) ([]GrepResult, error) {
+	return w.r.Grep(opts)
+}
+
 // findMatchInFiles takes a FileIter, worktree name and GrepOptions, and
 // returns a slice of GrepResult containing the result of regex pattern matching
 // in content of all the files.

worktree_test.go

@@ -2211,6 +2211,87 @@ func (s *WorktreeSuite) TestGrep(c *C) {
 	}
 }
 
+func (s *WorktreeSuite) TestGrepBare(c *C) {
+	cases := []struct {
+		name           string
+		options        GrepOptions
+		wantResult     []GrepResult
+		dontWantResult []GrepResult
+		wantError      error
+	}{
+		{
+			name: "basic word match",
+			options: GrepOptions{
+				Patterns:   []*regexp.Regexp{regexp.MustCompile("import")},
+				CommitHash: plumbing.ZeroHash,
+			},
+			wantResult: []GrepResult{
+				{
+					FileName:   "go/example.go",
+					LineNumber: 3,
+					Content:    "import (",
+					TreeName:   "6ecf0ef2c2dffb796033e5a02219af86ec6584e5",
+				},
+				{
+					FileName:   "vendor/foo.go",
+					LineNumber: 3,
+					Content:    "import \"fmt\"",
+					TreeName:   "6ecf0ef2c2dffb796033e5a02219af86ec6584e5",
+				},
+			},
+		},
+	}
+
+	path := fixtures.Basic().ByTag("worktree").One().Worktree().Root()
+
+	dir, clean := s.TemporalDir()
+	defer clean()
+
+	r, err := PlainClone(dir, true, &CloneOptions{
+		URL: path,
+	})
+	c.Assert(err, IsNil)
+
+	for _, tc := range cases {
+		gr, err := r.Grep(&tc.options)
+		if tc.wantError != nil {
+			c.Assert(err, Equals, tc.wantError)
+		} else {
+			c.Assert(err, IsNil)
+		}
+
+		// Iterate through the results and check if the wanted result is present
+		// in the got result.
+		for _, wantResult := range tc.wantResult {
+			found := false
+			for _, gotResult := range gr {
+				if wantResult == gotResult {
+					found = true
+					break
+				}
+			}
+			if !found {
+				c.Errorf("unexpected grep results for %q, expected result to contain: %v", tc.name, wantResult)
+			}
+		}
+
+		// Iterate through the results and check if the not wanted result is
+		// present in the got result.
+		for _, dontWantResult := range tc.dontWantResult {
+			found := false
+			for _, gotResult := range gr {
+				if dontWantResult == gotResult {
+					found = true
+					break
+				}
+			}
+			if found {
+				c.Errorf("unexpected grep results for %q, expected result to NOT contain: %v", tc.name, dontWantResult)
+			}
+		}
+	}
+}
+
 func (s *WorktreeSuite) TestResetLingeringDirectories(c *C) {
 	dir, clean := s.TemporalDir()
 	defer clean()