Cherry-pick 276124@main (846605f). rdar://124627200

    [git-webkit] Detect merge-back clone
    https://bugs.webkit.org/show_bug.cgi?id=270986
    rdar://124627200

    Reviewed by Aakash Jain.

    If the user doesn't specify a merge-back behavior when cloning,
    we can infer that behavior based on bug comments.

    * Tools/Scripts/libraries/webkitscmpy/webkitscmpy/program/clone.py:
    (Clone.parser): Add --no-merge-back option.
    (Clone.main): Push reason resolution below issue resolution. Attempt
    to determine the branch issue was committed to, and assume merge-back
    if the issue was not committed to the default branch.
    * Tools/Scripts/libraries/webkitscmpy/webkitscmpy/test/clone_unittest.py:
    (TestClone.test_infer_merge_back):

    Canonical link: https://commits.webkit.org/276124@main

Canonical link: https://commits.webkit.org/272448.739@safari-7618-branch

Tools/Scripts/libraries/webkitscmpy/webkitscmpy/program/clone.py

@@ -1,4 +1,4 @@
-# Copyright (C) 2023 Apple Inc. All rights reserved.
+# Copyright (C) 2023-2024 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -20,6 +20,7 @@
 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+import re
 import sys
 
 from .command import Command
@@ -33,6 +34,7 @@ class Clone(Command):
     name = 'clone'
     help = 'Clone the radar a bugzilla or commit refers to'
     UMBRELLA = b'\xe2\x98\x82\xef\xb8\x8f'.decode('utf-8')
+    COMMITTED_RE = re.compile(r'Committed \d+\.?\d+@\S+( \([a-f0-9A-F]+\))? to (?P<branch>\S*) referencing this bug')
 
     @classmethod
     def parser(cls, parser, loggers=None):
@@ -66,10 +68,10 @@ def parser(cls, parser, loggers=None):
             action='store_true',
         )
         parser.add_argument(
-            '--merge-back',
-            dest='merge_back', default=False,
+            '--merge-back', '--no-merge-back',
+            dest='merge_back', default=None,
             help='Annotate the cloned issue for merge-back',
-            action='store_true',
+            action=arguments.NoAction,
         )
 
     @classmethod
@@ -100,10 +102,10 @@ def parent(cls, rdar, milestone):
         ), None)
 
     @classmethod
-    def main(cls, args, repository, merge_back=False, **kwargs):
+    def main(cls, args, repository, merge_back=None, **kwargs):
         rdar = None
-        merge_back = merge_back or args.merge_back
-        prefix = '[merge-back]' if merge_back else ''
+        if args.merge_back is not None:
+            merge_back = args.merge_back
 
         for tracker in Tracker._trackers:
             if isinstance(tracker, radar.Tracker):
@@ -117,12 +119,6 @@ def main(cls, args, repository, merge_back=False, **kwargs):
                 sys.stderr.write('Radar is not available on this machine\n')
             return 255
 
-        if not args.reason and args.milestone:
-            args.reason = "Cloning for inclusion in '{}'".format(args.milestone)
-        if not args.reason:
-            sys.stderr.write('No reason for cloning issue has been provided\n')
-            return 255
-
         # First, check if we were provided a bug URL
         issue = Tracker.from_string(args.argument[0])
         if not issue:
@@ -160,6 +156,40 @@ def main(cls, args, repository, merge_back=False, **kwargs):
             sys.stderr.write("'{}' is not a radar, therefore cannot be cloned\n".format(issue))
             return 255
 
+        # Attempt to detect if this invocation is likely for merge-back
+        if merge_back is None:
+            on_default_branch = False
+            on_release_branch = False
+
+            branch = None
+            for comment in issue.comments:
+                mtch = cls.COMMITTED_RE.match(comment.content)
+                if mtch:
+                    branch = mtch.group('branch')
+                    if branch == repository.default_branch:
+                        on_default_branch = True
+                        break
+                    else:
+                        on_release_branch = True
+
+            if on_default_branch:
+                merge_back = False
+            elif on_release_branch and (args.prompt or Terminal.choose(
+                prompt='Change is on {} but not {}, would you like to create a merge-back clone?'.format(branch, repository.default_branch),
+                default='Yes',
+            ) == 'Yes'):
+                merge_back = True
+
+        prefix = '[merge-back]' if merge_back else ''
+
+        if not args.reason and merge_back:
+            args.reason = "Cloning for merge-back to {}".format(repository.default_branch)
+        if not args.reason and args.milestone:
+            args.reason = "Cloning for inclusion in '{}'".format(args.milestone)
+        if not args.reason:
+            sys.stderr.write('No reason for cloning issue has been provided\n')
+            return 255
+
         milestone = None
         raw_issue = rdar.client.radar_for_id(issue.id)
         milestones = {

Tools/Scripts/libraries/webkitscmpy/webkitscmpy/test/clone_unittest.py

@@ -1,4 +1,4 @@
-# Copyright (C) 2023 Apple Inc. All rights reserved.
+# Copyright (C) 2023-2024 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
@@ -239,3 +239,51 @@ def test_merge_back(self):
             "Created '[merge-back] rdar://5 Example issue 1'\n"
             'Moved clone to Internal Tools - October and into Analyze: Prepare\n',
         )
+
+    def test_infer_merge_back(self):
+        issues = [issue.copy() for issue in bmocks.ISSUES]
+        issues[0]['category'] = 'Important'
+
+        issues.append(dict(
+            title=u'{} merge-back October release'.format(program.Clone.UMBRELLA),
+            timestamp=int(time.time()),
+            opened=True,
+            creator=bmocks.USERS['Tim Contributor'],
+            assignee=bmocks.USERS['Tim Contributor'],
+            description='Umbrella bug tracking October merge-back',
+            project='WebKit',
+            component='Text',
+            version='Other',
+            milestone='October',
+        ))
+
+        with mocks.local.Git(self.path), mocks.local.Svn(), Environment(RADAR_USERNAME='tcontributor'), bmocks.Radar(
+            issues=issues,
+            projects=bmocks.PROJECTS,
+            milestones=bmocks.MILESTONES,
+        ), MockTerminal.input('y', '1'), OutputCapture() as captured, patch('webkitbugspy.Tracker._trackers', [radar.Tracker()]):
+            tracker = radar.Tracker()
+            tracker.issue(1).add_comment('Committed 1234.10@some-branch (12345678) to some-branch referencing this bug')
+
+            self.assertEqual(0, program.main(
+                args=('clone', 'rdar://1', '--milestone', 'October'),
+                path=self.path,
+            ))
+            raw_issue = tracker.client.radar_for_id(5)
+
+            self.assertEqual(raw_issue.milestone.name, 'Internal Tools - October')
+            self.assertEqual(raw_issue.category.name, 'Important')
+            self.assertIsNone(raw_issue.event)
+            self.assertIsNone(raw_issue.tentpole)
+
+            parents = tracker.issue(5).related.get('subtask-of')
+            self.assertEqual(1, len(parents))
+            self.assertEqual(parents[0].title, u'{} merge-back October release'.format(program.Clone.UMBRELLA))
+
+        self.assertEqual(captured.stderr.getvalue(), '')
+        self.assertEqual(
+            captured.stdout.getvalue(),
+            "Change is on some-branch but not main, would you like to create a merge-back clone? ([Yes]/No): \n"
+            "Created '[merge-back] rdar://5 Example issue 1'\n"
+            'Moved clone to Internal Tools - October and into Analyze: Prepare\n',
+        )