refactor(release): factor out loops in process-backports into helpers

Author: rickeylev

tools/private/release/process_backports.py

@@ -1,6 +1,7 @@
 """Subcommand to process pending backports."""
 
 import datetime
+from typing import Any
 
 from tools.private.release import changelog_news, gh, git
 from tools.private.release.release_issue import (
@@ -11,46 +12,9 @@
 from tools.private.release.utils import get_latest_rc_tag
 
 
-def cmd_process_backports(args):
-    """Executes the process-backports subcommand."""
-    body = gh.get_issue_body(args.issue)
-    items = parse_backports(body)
-
-    pending_items = [
-        item
-        for item in items
-        if not item.checked and not item.status.startswith("error-")
-    ]
-
-    if not pending_items:
-        print("No pending backports found.")
-        return 0
-
-    print(f"Found {len(pending_items)} pending backports to process.")
-
-    # Determine branch name from issue title
-    issue_title = gh.get_issue_title(args.issue)
-    version_match = RELEASE_TITLE_RE.search(issue_title)
-    if not version_match:
-        print(f"Error: Could not parse version from issue title: {issue_title}")
-        return 1
-
-    version = version_match.group(1)
-    branch_version = ".".join(version.split(".")[:2])
-    branch_name = f"release/{branch_version}"
-
-    # Determine next RC tag to write to backport metadata
-    git.fetch(args.remote, tags=True, force=True)
-    latest_rc = get_latest_rc_tag(version, remote=args.remote)
-    if not latest_rc:
-        next_rc_suffix = "rc0"
-    else:
-        rc_num = int(latest_rc.split("-rc")[-1])
-        next_rc_suffix = f"rc{rc_num + 1}"
-
-    # Resolve PRs to merge commits using gh helper.
-    pr_commit_infos = gh.get_merge_commits_for_prs(pending_items)
-
+def _process_pr_commit_infos(
+    pr_commit_infos, body, issue, dry_run
+) -> tuple[list[str], dict[str, Any], list[str], list[str], str]:
     shas = []
     sha_to_item = {}
     failed_prs = []
@@ -64,11 +28,9 @@ def cmd_process_backports(args):
             print(f"PR {item.pr_ref} is open or draft. Ignoring.")
             ignored_prs.append(item.pr_ref)
         else:
-            # Handle case where PR could not be resolved to a merge commit.
-            # We immediately mark it as failed in the tracking issue.
             failed_prs.append(item.pr_ref)
             status_to_set = item.status or "error-unmerged-pr"
-            if args.dry_run:
+            if dry_run:
                 print(
                     f"[DRY RUN] Would update tracking issue checklist for unresolved PR {item.pr_ref} to status={status_to_set}"
                 )
@@ -83,58 +45,50 @@ def cmd_process_backports(args):
                         checked=False,
                         metadata={"status": status_to_set},
                     )
-                    gh.update_issue_body(args.issue, body)
+                    gh.update_issue_body(issue, body)
                 except Exception as e:
                     print(
                         f"ERROR: Failed to update tracking issue for unresolved PR {item.pr_ref}: {e}"
                     )
-
-    if not shas:
-        print("No valid merge commits to process.")
-        if failed_prs:
-            print("Failed PRs:")
-            for pr in failed_prs:
-                print(f"- {pr}")
-            return 1
-        return 0
-
-    # Verify workspace is clean before proceeding
-    if git.status():
-        print(
-            "ERROR: Git workspace is dirty. Please commit or stash changes before running backports."
-        )
-        return 1
-
-    # Sort chronologically using git helper
-    sorted_shas = git.sort_commits_chronologically(shas)
-
-    git.fetch(args.remote)
-    git.checkout(branch_name, track_remote=args.remote)
-
+    return shas, sha_to_item, failed_prs, ignored_prs, body
+
+
+def _cherry_pick_and_update_prs(
+    sorted_shas,
+    sha_to_item,
+    body,
+    issue,
+    remote,
+    dry_run,
+    version,
+    branch_name,
+    next_rc_suffix,
+) -> tuple[list[str], str]:
+    failed_prs = []
     for sha in sorted_shas:
         item = sha_to_item[sha]
         print(f"Cherry-picking {item.pr_ref} / {sha}...")
         try:
-            git.cherry_pick(sha, no_commit=args.dry_run)
+            git.cherry_pick(sha, no_commit=dry_run)
 
             # Perform news processing (merging news/ files into the changelog)
             print(f"Merging news fragments into changelog for PR {item.pr_ref}...")
             release_date = datetime.date.today().strftime("%Y-%m-%d")
             changelog_news.update_changelog(version, release_date)
 
-            if not args.dry_run:
+            if not dry_run:
                 # Stage changelog changes and news/ deletions
                 git.add("CHANGELOG.md", "news/")
 
                 # Amend cherry-pick commit to include news merging and deletions,
                 # and reference the release tracking issue.
                 print(f"Amending cherry-pick commit for PR {item.pr_ref}...")
                 current_msg = git.get_commit_message("HEAD")
-                new_msg = f"{current_msg.strip()}\n\nWork towards #{args.issue}"
+                new_msg = f"{current_msg.strip()}\n\nWork towards #{issue}"
                 git.commit(new_msg, amend=True)
 
                 # Push amended commit
-                git.push(args.remote, branch_name)
+                git.push(remote, branch_name)
 
                 new_sha = git.get_commit_sha("HEAD", short=True)
                 metadata = {"status": "done", "rc": next_rc_suffix, "commit": new_sha}
@@ -143,7 +97,7 @@ def cmd_process_backports(args):
                     body = update_task_in_body(
                         body, item.pr_ref, checked=True, metadata=metadata
                     )
-                    gh.update_issue_body(args.issue, body)
+                    gh.update_issue_body(issue, body)
                 except Exception as e:
                     print(
                         f"ERROR: Failed to update tracking issue for PR {item.pr_ref}: {e}"
@@ -164,7 +118,7 @@ def cmd_process_backports(args):
                 pass
             failed_prs.append(item.pr_ref)
 
-            if args.dry_run:
+            if dry_run:
                 print(
                     f"[DRY RUN] Would update tracking issue checklist for failed PR {item.pr_ref} to status=error-merge-conflict"
                 )
@@ -179,7 +133,7 @@ def cmd_process_backports(args):
                         checked=False,
                         metadata={"status": "error-merge-conflict"},
                     )
-                    gh.update_issue_body(args.issue, body)
+                    gh.update_issue_body(issue, body)
                     print(
                         f"Updated back port of {item.pr_ref} to status=error-merge-conflict (unchecked)"
                     )
@@ -188,8 +142,89 @@ def cmd_process_backports(args):
                         f"ERROR: Failed to update tracking issue for failed PR {item.pr_ref}: {e}"
                     )
         finally:
-            if args.dry_run:
+            if dry_run:
                 git.reset_hard("HEAD")
+    return failed_prs, body
+
+
+def cmd_process_backports(args):
+    """Executes the process-backports subcommand."""
+    body = gh.get_issue_body(args.issue)
+    items = parse_backports(body)
+
+    pending_items = [
+        item
+        for item in items
+        if not item.checked and not item.status.startswith("error-")
+    ]
+
+    if not pending_items:
+        print("No pending backports found.")
+        return 0
+
+    print(f"Found {len(pending_items)} pending backports to process.")
+
+    # Determine branch name from issue title
+    issue_title = gh.get_issue_title(args.issue)
+    version_match = RELEASE_TITLE_RE.search(issue_title)
+    if not version_match:
+        print(f"Error: Could not parse version from issue title: {issue_title}")
+        return 1
+
+    version = version_match.group(1)
+    branch_version = ".".join(version.split(".")[:2])
+    branch_name = f"release/{branch_version}"
+
+    # Determine next RC tag to write to backport metadata
+    git.fetch(args.remote, tags=True, force=True)
+    latest_rc = get_latest_rc_tag(version, remote=args.remote)
+    if not latest_rc:
+        next_rc_suffix = "rc0"
+    else:
+        rc_num = int(latest_rc.split("-rc")[-1])
+        next_rc_suffix = f"rc{rc_num + 1}"
+
+    # Resolve PRs to merge commits using gh helper.
+    pr_commit_infos = gh.get_merge_commits_for_prs(pending_items)
+
+    shas, sha_to_item, failed_prs, ignored_prs, body = _process_pr_commit_infos(
+        pr_commit_infos, body, args.issue, args.dry_run
+    )
+
+    if not shas:
+        print("No valid merge commits to process.")
+        if failed_prs:
+            print("Failed PRs:")
+            for pr in failed_prs:
+                print(f"- {pr}")
+            return 1
+        return 0
+
+    # Verify workspace is clean before proceeding
+    if git.status():
+        print(
+            "ERROR: Git workspace is dirty. Please commit or stash changes before running backports."
+        )
+        return 1
+
+    # Sort chronologically using git helper
+    sorted_shas = git.sort_commits_chronologically(shas)
+
+    git.fetch(args.remote)
+    git.checkout(branch_name, track_remote=args.remote)
+
+    new_failed_prs, body = _cherry_pick_and_update_prs(
+        sorted_shas,
+        sha_to_item,
+        body,
+        args.issue,
+        args.remote,
+        args.dry_run,
+        version,
+        branch_name,
+        next_rc_suffix,
+    )
+    failed_prs.extend(new_failed_prs)
 
     if failed_prs:
         print("ERROR: One or more cherry-picks/resolutions failed:")