Add orig_parent to create change descriptions.

Bug: 1426333
Change-Id: I9a199d98aad7ca5133dfa85dd632ffc22f89e421
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4370432
Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Joanna Wang <jojwang@chromium.org>

git_cl.py

@@ -1686,14 +1686,29 @@ class Changelist(object):
     # branch/change.
     return refspec_opts
 
-  def PrepareSquashedCommit(self, options, parent, end_commit=None):
-    # type: (optparse.Values, str, Optional[str]) -> _NewUpload()
-    """Create a squashed commit to upload."""
+  def PrepareSquashedCommit(self,
+                            options,
+                            parent,
+                            orig_parent,
+                            end_commit=None):
+    # type: (optparse.Values, str, str, Optional[str]) -> _NewUpload()
+    """Create a squashed commit to upload.
+
+
+      Args:
+        parent: The commit to use as the parent for the new squashed.
+        orig_parent: The commit that is an actual ancestor of `end_commit`. It
+            is part of the same original tree as end_commit, which does not
+            contain squashed commits. This is used to create the change
+            description for the new squashed commit with:
+            `git log orig_parent..end_commit`.
+        end_commit: The commit to use as the end of the new squashed commit.
+    """
 
     if end_commit is None:
       end_commit = RunGit(['rev-parse', self.branchref]).strip()
 
-    reviewers, ccs, change_desc = self._PrepareChange(options, parent,
+    reviewers, ccs, change_desc = self._PrepareChange(options, orig_parent,
                                                       end_commit)
     latest_tree = RunGit(['rev-parse', end_commit + ':']).strip()
     with gclient_utils.temporary_file() as desc_tempfile:
@@ -4870,6 +4885,7 @@ def UploadAllSquashed(options, orig_args):
     # We can only support external changes when we're only uploading one
     # branch.
     parent = cl._UpdateWithExternalChanges() if len(ordered_cls) == 1 else None
+    orig_parent = None
     if parent is None:
       origin = '.'
       branch = cl.GetBranch()
@@ -4884,6 +4900,9 @@ def UploadAllSquashed(options, orig_args):
           if upstream_branch in ['master', 'main']:
             parent = cl.GetCommonAncestorWithUpstream()
           else:
+            orig_parent = scm.GIT.GetBranchConfig(settings.GetRoot(),
+                                                  upstream_branch,
+                                                  LAST_UPLOAD_HASH_CONFIG_KEY)
             parent = scm.GIT.GetBranchConfig(settings.GetRoot(),
                                              upstream_branch,
                                              GERRIT_SQUASH_HASH_CONFIG_KEY)
@@ -4896,6 +4915,8 @@ def UploadAllSquashed(options, orig_args):
         # tree.
         parent = cl.GetCommonAncestorWithUpstream()
 
+    if orig_parent is None:
+      orig_parent = parent
     for i, cl in enumerate(ordered_cls):
       # If we're in the middle of the stack, set end_commit to downstream's
       # direct ancestor.
@@ -4905,9 +4926,11 @@ def UploadAllSquashed(options, orig_args):
         child_base_commit = None
       new_upload = cl.PrepareSquashedCommit(options,
                                             parent,
+                                            orig_parent,
                                             end_commit=child_base_commit)
       uploads_by_cl.append((cl, new_upload))
       parent = new_upload.commit_to_push
+      orig_parent = child_base_commit
 
   # Create refspec options
   cl, new_upload = uploads_by_cl[-1]

tests/git_cl_test.py

@@ -1653,11 +1653,16 @@ class TestGitCl(unittest.TestCase):
     git_cl.UploadAllSquashed(options, orig_args)
 
     # Asserts
+    self.maxDiff = None
     self.assertEqual(mockSquashedCommit.mock_calls, [
         mock.call(options,
+                  'current-upstream-ancestor',
                   'current-upstream-ancestor',
                   end_commit='next-upstream-ancestor'),
-        mock.call(options, upstream_commit_to_push, end_commit=None)
+        mock.call(options,
+                  upstream_commit_to_push,
+                  'next-upstream-ancestor',
+                  end_commit=None)
     ])
 
     expected_refspec = ('commit-to-push:refs/for/refs/heads/main%notify=NONE,'
@@ -1737,8 +1742,10 @@ class TestGitCl(unittest.TestCase):
     git_cl.UploadAllSquashed(options, orig_args)
 
     # Asserts
-    self.assertEqual(mockSquashedCommit.mock_calls,
-                     [mock.call(options, 'external-commit', end_commit=None)])
+    self.assertEqual(mockSquashedCommit.mock_calls, [
+        mock.call(
+            options, 'external-commit', 'external-commit', end_commit=None)
+    ])
 
     expected_refspec = ('commit-to-push:refs/for/refs/heads/main%notify=NONE,'
                         'm=honk_stonk,topic=circus,hashtag=cow')
@@ -1760,9 +1767,12 @@ class TestGitCl(unittest.TestCase):
     git_cl.UploadAllSquashed(options, orig_args)
 
     # Asserts
-    self.assertEqual(
-        mockSquashedCommit.mock_calls,
-        [mock.call(options, 'current-upstream-ancestor', end_commit=None)])
+    self.assertEqual(mockSquashedCommit.mock_calls, [
+        mock.call(options,
+                  'current-upstream-ancestor',
+                  'current-upstream-ancestor',
+                  end_commit=None)
+    ])
 
   @mock.patch(
       'git_cl.Changelist._GerritCommitMsgHookCheck', lambda offer_removal: None)
@@ -4005,6 +4015,7 @@ class ChangelistTest(unittest.TestCase):
     mockPrepareChange.return_value = (reviewers, ccs, change_desc)
 
     parent_hash = 'upstream-gerrit-hash'
+    parent_orig_hash = 'upstream-last-upload-hash'
     parent_hash_root = 'root-commit'
     hash_to_push = 'new-squash-hash'
     hash_to_push_root = 'new-squash-hash-root'
@@ -4028,13 +4039,14 @@ class ChangelistTest(unittest.TestCase):
     cl = git_cl.Changelist(branchref=branchref)
     options = optparse.Values()
 
-    new_upload = cl.PrepareSquashedCommit(options, parent_hash)
+    new_upload = cl.PrepareSquashedCommit(options, parent_hash,
+                                          parent_orig_hash)
     self.assertEqual(new_upload.reviewers, reviewers)
     self.assertEqual(new_upload.ccs, ccs)
     self.assertEqual(new_upload.commit_to_push, hash_to_push)
     self.assertEqual(new_upload.new_last_uploaded_commit, end_hash)
     self.assertEqual(new_upload.change_desc, change_desc)
-    mockPrepareChange.assert_called_with(options, parent_hash, end_hash)
+    mockPrepareChange.assert_called_with(options, parent_orig_hash, end_hash)
 
   @mock.patch('git_cl.Settings.GetRoot', return_value='')
   @mock.patch('git_cl.Changelist.GetMostRecentPatchset', return_value=2)