git diff support --name-only option

Author: Unpublished

git/diff.py

@@ -187,7 +187,14 @@ def diff(
         kwargs["as_process"] = True
         proc = diff_cmd(*self._process_diff_args(args), **kwargs)
 
-        diff_method = Diff._index_from_patch_format if create_patch else Diff._index_from_raw_format
+        cmdline = getattr(proc, 'args', '')  # PY3+ only
+
+        if '--name-only' in cmdline:
+            diff_method = Diff._index_from_name_only_format
+        elif create_patch:
+            diff_method = Diff._index_from_patch_format
+        else:
+            diff_method = Diff._index_from_raw_format
         index = diff_method(self.repo, proc)
 
         proc.wait()
@@ -569,6 +576,34 @@ def _index_from_patch_format(cls, repo: "Repo", proc: Union["Popen", "Git.AutoIn
 
         return index
 
+    @classmethod
+    def _index_from_name_only_format(cls, repo, proc):
+        """Create a new DiffIndex from the given text which must be in name only format
+        :param repo: is the repository we are operating on - it is required
+        :param stream: result of 'git diff' as a stream (supporting file protocol)
+        :return: git.DiffIndex """
+
+        cls.is_first = True
+
+        index = DiffIndex()
+
+        def handle_diff_line_name_only(line):
+            path = line.decode(defenc)
+            if cls.is_first:
+                cls.is_first = False
+                return
+
+            path = path.strip()
+            a_path = path.encode(defenc)
+            b_path = path.encode(defenc)
+            index.append(Diff(repo, a_path, b_path, None, None, None, None,
+                              False, False, None, None, None,
+                              '', None, None))
+
+        handle_process_output(proc, handle_diff_line_name_only, None, finalize_process, decode_streams=False)
+
+        return index
+
     @staticmethod
     def _handle_diff_line(lines_bytes: bytes, repo: "Repo", index: DiffIndex) -> None:
         lines = lines_bytes.decode(defenc)

test/test_diff.py

@@ -263,6 +263,19 @@ def test_diff_initial_commit(self):
         self.assertIsNotNone(diff_index[0].new_file)
         self.assertEqual(diff_index[0].diff, fixture("diff_initial"))
 
+    def test_diff_initial_commit_name_only(self):
+        initial_commit = self.rorepo.commit('33ebe7acec14b25c5f84f35a664803fcab2f7781')
+
+        # Without creating a patch...
+        diff_index = initial_commit.diff(NULL_TREE, **{'name-only': True})
+        self.assertEqual(diff_index[0].a_path, 'CHANGES')
+        self.assertEqual(diff_index[0].b_path, 'CHANGES')
+
+        # ...and with creating a patch
+        diff_index = initial_commit.diff(NULL_TREE, create_patch=True, **{'name-only': True})
+        self.assertEqual(diff_index[0].a_path, 'CHANGES')
+        self.assertEqual(diff_index[0].b_path, 'CHANGES')
+
     def test_diff_unsafe_paths(self):
         output = StringProcessAdapter(fixture("diff_patch_unsafe_paths"))
         res = Diff._index_from_patch_format(None, output)