[Fix]: Fix bugs for target_branch param on resolver (#5745)

Co-authored-by: openhands <openhands@all-hands.dev>

Author: malhotra5

openhands/resolver/resolve_issue.py

@@ -307,7 +307,6 @@ async def resolve_issue(
     repo_instruction: str | None,
     issue_number: int,
     comment_id: int | None,
-    target_branch: str | None = None,
     reset_logger: bool = False,
 ) -> None:
     """Resolve a single github issue.
@@ -326,7 +325,7 @@ async def resolve_issue(
         repo_instruction: Repository instruction to use.
         issue_number: Issue number to resolve.
         comment_id: Optional ID of a specific comment to focus on.
-        target_branch: Optional target branch to create PR against (for PRs).
+
         reset_logger: Whether to reset the logger for multiprocessing.
     """
     issue_handler = issue_handler_factory(issue_type, owner, repo, token, llm_config)
@@ -424,9 +423,9 @@ async def resolve_issue(
     try:
         # checkout to pr branch if needed
         if issue_type == 'pr':
-            branch_to_use = target_branch if target_branch else issue.head_branch
+            branch_to_use = issue.head_branch
             logger.info(
-                f'Checking out to PR branch {target_branch} for issue {issue.number}'
+                f'Checking out to PR branch {branch_to_use} for issue {issue.number}'
             )
 
             if not branch_to_use:
@@ -446,10 +445,6 @@ async def resolve_issue(
                 cwd=repo_dir,
             )
 
-            # Update issue's base_branch if using custom target branch
-            if target_branch:
-                issue.base_branch = target_branch
-
             base_commit = (
                 subprocess.check_output(['git', 'rev-parse', 'HEAD'], cwd=repo_dir)
                 .decode('utf-8')
@@ -644,7 +639,6 @@ def int_or_none(value):
             repo_instruction=repo_instruction,
             issue_number=my_args.issue_number,
             comment_id=my_args.comment_id,
-            target_branch=my_args.target_branch,
         )
     )
 

tests/unit/resolver/test_send_pull_request.py

@@ -500,6 +500,111 @@ def test_send_pull_request_with_reviewer(
     assert result == 'https://github.com/test-owner/test-repo/pull/1'
 
 
+@patch('subprocess.run')
+@patch('requests.post')
+@patch('requests.get')
+def test_send_pull_request_target_branch_with_fork(
+    mock_get, mock_post, mock_run, mock_github_issue, mock_output_dir
+):
+    """Test that target_branch works correctly when using a fork."""
+    repo_path = os.path.join(mock_output_dir, 'repo')
+    fork_owner = 'fork-owner'
+    target_branch = 'custom-target'
+
+    # Mock API responses
+    mock_get.side_effect = [
+        MagicMock(status_code=404),  # Branch doesn't exist
+        MagicMock(status_code=200),  # Target branch exists
+    ]
+
+    mock_post.return_value.json.return_value = {
+        'html_url': 'https://github.com/test-owner/test-repo/pull/1'
+    }
+
+    # Mock subprocess.run calls
+    mock_run.side_effect = [
+        MagicMock(returncode=0),  # git checkout -b
+        MagicMock(returncode=0),  # git push
+    ]
+
+    # Call the function with fork_owner and target_branch
+    result = send_pull_request(
+        github_issue=mock_github_issue,
+        github_token='test-token',
+        github_username='test-user',
+        patch_dir=repo_path,
+        pr_type='ready',
+        fork_owner=fork_owner,
+        target_branch=target_branch,
+    )
+
+    # Assert API calls
+    assert mock_get.call_count == 2
+    
+    # Verify target branch was checked in original repo, not fork
+    target_branch_check = mock_get.call_args_list[1]
+    assert target_branch_check[0][0] == f'https://api.github.com/repos/test-owner/test-repo/branches/{target_branch}'
+
+    # Check PR creation
+    mock_post.assert_called_once()
+    post_data = mock_post.call_args[1]['json']
+    assert post_data['base'] == target_branch  # PR should target the specified branch
+    assert post_data['head'] == 'openhands-fix-issue-42'  # Branch name should be standard
+
+    # Check that push was to fork
+    push_call = mock_run.call_args_list[1]
+    assert f'https://test-user:test-token@github.com/{fork_owner}/test-repo.git' in str(push_call)
+
+
+@patch('subprocess.run')
+@patch('requests.post')
+@patch('requests.get')
+def test_send_pull_request_target_branch_with_additional_message(
+    mock_get, mock_post, mock_run, mock_github_issue, mock_output_dir
+):
+    """Test that target_branch works correctly with additional PR message."""
+    repo_path = os.path.join(mock_output_dir, 'repo')
+    target_branch = 'feature-branch'
+    additional_message = 'Additional PR context'
+
+    # Mock API responses
+    mock_get.side_effect = [
+        MagicMock(status_code=404),  # Branch doesn't exist
+        MagicMock(status_code=200),  # Target branch exists
+    ]
+
+    mock_post.return_value.json.return_value = {
+        'html_url': 'https://github.com/test-owner/test-repo/pull/1'
+    }
+
+    # Mock subprocess.run calls
+    mock_run.side_effect = [
+        MagicMock(returncode=0),  # git checkout -b
+        MagicMock(returncode=0),  # git push
+    ]
+
+    # Call the function with target_branch and additional_message
+    result = send_pull_request(
+        github_issue=mock_github_issue,
+        github_token='test-token',
+        github_username='test-user',
+        patch_dir=repo_path,
+        pr_type='ready',
+        target_branch=target_branch,
+        additional_message=additional_message,
+    )
+
+    # Assert API calls
+    assert mock_get.call_count == 2
+
+    # Check PR creation
+    mock_post.assert_called_once()
+    post_data = mock_post.call_args[1]['json']
+    assert post_data['base'] == target_branch
+    assert additional_message in post_data['body']
+    assert 'This pull request fixes #42' in post_data['body']
+
+
 @patch('requests.get')
 def test_send_pull_request_invalid_target_branch(
     mock_get, mock_github_issue, mock_output_dir