dev10x-git-fixup

name	Dev10x:git-fixup
description	Create a fixup! commit for a PR review comment or standalone improvement. Enforces one fixup per comment thread when linked to a review. TRIGGER when: creating a fixup! commit for a review finding or standalone improvement. DO NOT TRIGGER when: creating a regular commit (use Dev10x:git-commit), or implementing PR fixes with push and reply (use Dev10x:gh-pr-fixup).
user-invocable	true
invocation-name	Dev10x:git-fixup
allowed-tools	["Bash(/tmp/Dev10x/bin/mktmp.sh:*)","Bash(${CLAUDE_PLUGIN_ROOT}/skills/git-fixup/scripts/:*)","Edit(/tmp/Dev10x/git/**)","mcp__plugin_Dev10x_cli__pr_detect","mcp__plugin_Dev10x_cli__pr_comments","mcp__plugin_Dev10x_cli__push_safe"]

Create Fixup Commit

Orchestration

This skill follows references/task-orchestration.md patterns. Create a task at invocation, mark completed when done:

REQUIRED: Create a task at invocation. Execute at startup:

1. TaskCreate(subject="Create fixup commit", activeForm="Creating fixup")

Mark completed when done: TaskUpdate(taskId, status="completed")

Overview

This skill creates properly scoped fixup! commits. Two modes:

1. Review fixup — addresses a specific PR review comment (one fixup per comment thread, comment link required in body)
2. Standalone fixup — self-initiated improvement not tied to a review comment (marked with Standalone fixup in body)

Why fixup commits?

• Reviewers can verify each fix individually
• Easy to match "comment → fixup commit"
• git rebase -i --autosquash squashes them into the target commit

When to Use This Skill

• Called by Dev10x:gh-pr-fixup when addressing review comments
• When you need to create a fixup commit for a specific review comment
• When you need a standalone fixup for a self-initiated improvement
• When you fix a bug or anti-pattern that belongs to a prior commit in the branch — use Dev10x:git-fixup immediately rather than a standalone commit that would need converting later
• NOT for general commits (use Dev10x:git-commit skill instead)

Input Requirements

Parameter	Required	Description
pr_number	No	The pull request number (omit for standalone)
comment_id	No	The GitHub comment ID being addressed
repository	No	Owner/repo (defaults to current repo)

If neither pr_number nor comment_id is provided, prompt the user to confirm this is a standalone fixup before proceeding.

Workflow

Step 0: Verify CWD is the target repository

REQUIRED: Before any git operation, verify the working directory matches the expected repository:

git rev-parse --show-toplevel

Compare the output against the expected repo path. If they differ, STOP — do not use git -C as a workaround. Instead:

• If in a worktree setup, call EnterWorktree to switch to the correct worktree first
• If the repo is not checked out, inform the caller

This prevents the cascade of git -C usage that follows when the CWD is wrong. The git -C flag is NEVER permitted in this skill (see Important Notes).

Step 1: Determine Mode

If a comment ID or PR comment URL was provided → review fixup mode.

If the invocation args include a target commit SHA + description (e.g. /Dev10x:git-fixup abc1234 Fix null handling in phone lookup), intent is clear — proceed directly in standalone fixup mode without asking.

Otherwise, use AskUserQuestion to ask:

"No review comment provided. Create a standalone fixup?"

Options: "Yes, standalone fixup" / "No, use /Dev10x:git-commit instead"

If the user confirms → standalone fixup mode. If the user declines → suggest using /Dev10x:git-commit instead.

Step 2: Fetch Comment Details (review fixup only)

Skip this step entirely for standalone fixups.

# Resolve repo from current CWD
mcp__plugin_Dev10x_cli__pr_detect(arg="")
# → returns {"repo": "owner/repo", "pr_number": ..., "branch": ...}

# Fetch the comment by ID
mcp__plugin_Dev10x_cli__pr_comments(action="get", comment_id=<id>)

Extract from comment:

• path - File the comment is on
• line / original_line - Line number context
• diff_hunk - Code context
• html_url - Link to comment thread (for commit body)
• body - The review comment text

Step 3: Identify Original Commit (line-owning, not topical)

Resolve the fixup target by blaming the staged hunks — the target is the commit that last touched the lines being changed, not "the first commit on the branch". Topical attribution causes cross-commit fixups: when autosquash reorders the fixup next to its supposed target, a later branch commit that owns the touched lines no longer applies, producing modify/delete or content conflicts. git rerere then memoizes the bad resolution and silently re-applies it on the next attempt (GH-299).

Run the resolver script:

${CLAUDE_PLUGIN_ROOT}/skills/git-fixup/scripts/find-fixup-target.py

It reads git diff --cached, blames every hunk's pre-image line range against branch commits (<base>..HEAD), and prints JSON. Branch the SKILL on the status field:

status	Meaning	Action
single	All staged hunks blame to one branch commit	ORIGINAL_COMMIT=$target, ORIGINAL_MESSAGE=$subject — proceed to Step 4
multi	Hunks span ≥ 2 owning branch commits	Abort with the multi-owner guidance below — do NOT create a cross-commit fixup
out_of_branch	All hunks blame to commits outside <base>..HEAD	Fall back to fallback_target (first branch commit) — new file or untouched region
no_staged	Nothing staged	Surface the "No staged changes" error from § Error Handling
error	Resolver failed	Print the error field and stop

Multi-owner handling (status == "multi"):

Print the owner list returned by the script and stop. Example:

This fix touches lines owned by multiple branch commits — creating
one fixup against any single target would conflict on autosquash.
Restage and commit per owning commit:

  abc1234 (♻️ PAY-32 Tighten Square timeout handling)
    src/payments/service.py:120-128
    src/payments/service.py:204-210

  def5678 (✅ PAY-32 Add Square timeout regression tests)
    tests/payments/test_service.py:45-60

Suggested workflow (one fixup per owner):

  git restore --staged .
  git add -p src/payments/service.py        # stage only abc1234's hunks
  Skill(Dev10x:git-fixup)
  git add -p tests/payments/test_service.py # stage only def5678's hunks
  Skill(Dev10x:git-fixup)

Each fixup may reference the same review comment URL — the
"one fixup per comment" rule is a traceability floor, not a hard
cap. Multiple fixups for one comment are correct when the change
spans owning commits.

The skill MUST NOT silently pick one owner and create the fixup anyway — the whole point of this step is to refuse cross-commit fixups that autosquash cannot fold cleanly.

Step 4: Validate Staged Changes

Check what's staged:

git diff --cached --name-only

Validation rules:

1. At least one file must be staged
2. Staged files should relate to the comment's file path
3. Warn if staging files unrelated to the comment

If unrelated files are staged:

Warning: The following staged files may be unrelated to comment on {path}:
- {unrelated_file_1}
- {unrelated_file_2}

Continue anyway? (y/n)

Step 5: Build Commit Message

Review fixup format:

fixup! {original_commit_message}

Addresses review comment:
{comment_html_url}

Standalone fixup format:

fixup! {original_commit_message}

Standalone fixup
{description of what this fixes and why}

Review fixup example:

fixup! ✅ QA-159 add E2E tests for customer required before payment

Addresses review comment:
https://github.com/example-org/app-e2e/pull/269#discussion_r2706078039

Standalone fixup example:

fixup! ✨ PAY-518 Return make, model and VIN in trim lookups

Standalone fixup
Remove duplicate flat attributes and encapsulate data
in PosSubModelNode for cohesion.

Step 6: Create the Commit

IMPORTANT: Never use cat <<EOF or heredoc syntax — the validate-bash-security.py hook blocks it. Use Write tool + git commit -F.

Create a unique temp file via mktemp to avoid cross-session collisions:

/tmp/Dev10x/bin/mktmp.sh git fixup-msg .txt

Store the returned path for subsequent steps.

Review fixup:

# 1. Write message to the unique temp file (use Write tool, NOT echo/cat)
Write "<unique-path>" with:
  fixup! {ORIGINAL_MESSAGE}

  Addresses review comment:
  {COMMENT_URL}

# 2. Commit with -F
git commit -F <unique-path>

Standalone fixup:

# 1. Write message to the unique temp file (use Write tool)
Write "<unique-path>" with:
  fixup! {ORIGINAL_MESSAGE}

  Standalone fixup
  {DESCRIPTION}

# 2. Commit with -F
git commit -F <unique-path>

Step 7: Verify and Return

# Get the new commit hash
COMMIT_HASH=$(git rev-parse --short HEAD)
FULL_HASH=$(git rev-parse HEAD)

# Use PR-based URL when PR number is available (review fixup mode).
# PR-based URLs (pull/NUMBER/commits/HASH) let reviewers comment on
# the diff within the PR context. Standalone /commit/HASH URLs create
# comments disconnected from the PR review thread.
if [ -n "${PR_NUMBER:-}" ]; then
  COMMIT_URL="https://github.com/${REPO}/pull/${PR_NUMBER}/commits/${FULL_HASH}"
else
  COMMIT_URL="https://github.com/${REPO}/commit/${FULL_HASH}"
fi

echo "Created fixup commit: ${COMMIT_HASH}"
echo "URL: ${COMMIT_URL}"

Completion: Signal completion silently via TaskUpdate (status="completed"). Do not output "Returning to caller" messages — they mislead users in nested skill execution into thinking the workflow is done when the parent still has steps.

The caller reads these values from git state:

• commit_hash — git rev-parse --short HEAD
• commit_url — constructed from repo + PR number + full hash

Pre-commit Hook Integration

This skill works with the check-fixup-comment-link pre-commit hook which validates:

1. If commit message starts with fixup!
2. Body must contain either:
   • Exactly ONE GitHub comment thread link, OR
   • The Standalone fixup marker
3. Link format: https://github.com/{owner}/{repo}/pull/{pr}#discussion_r{id}

The hook will reject fixup commits that:

• Have neither a comment link nor a Standalone fixup marker
• Have multiple comment links (violates one-fixup-per-comment rule)

Error Handling

No Staged Changes

Error: No changes staged for commit.
Stage changes first with: git add {file}

Comment Not Found

Error: Could not fetch comment {comment_id}.
Verify the comment ID and repository.

Pre-commit Hook Rejection

Error: Fixup commit must reference exactly one comment thread.

Your commit body should contain a line like:
https://github.com/owner/repo/pull/123#discussion_r456789

This links the fixup to the specific review comment it addresses.

Integration with Dev10x:gh-pr-fixup

The Dev10x:gh-pr-fixup skill calls this skill instead of creating commits directly:

Dev10x:gh-pr-fixup workflow:
1. Analyze comment
2. Implement fix
3. Stage changes: git add {file}
4. Call Dev10x:git-fixup with (pr_number, comment_id)  <-- uses this skill
5. Push: mcp__plugin_Dev10x_cli__push_safe
6. Reply to comment with commit reference

Important Notes

• One fixup per comment — enforced by pre-commit hook (review mode)
• Comment link or standalone marker required — enables traceability
• Scoped changes — warns about unrelated files (review mode)
• Works with autosquash — git rebase -i --autosquash will squash these
• Prompt before standalone — use AskUserQuestion to confirm; never silently proceed in standalone mode
• Always use plain git — NEVER use git -C <path>. The session CWD is already the repo. git -C creates duplicate allow-rules in settings.local.json and will require permission prompts after a fresh start.

Example Usage

Review fixup (called by Dev10x:gh-pr-fixup)

# Stage the fix
git add tests/pages/crm.py

# Create fixup — skill fetches comment and builds message
# Input: comment URL or PR 269, comment 2706078039

Result:

fixup! ✅ QA-159 add E2E tests for customer required before payment

Addresses review comment:
https://github.com/example-org/app-e2e/pull/269#discussion_r2706078039

Standalone fixup (self-initiated improvement)

# Stage the fix
git add src/app_pos/motor/api/nodes.py

# Invoke /Dev10x:git-fixup with no comment argument
# Claude asks: "No review comment provided. Create a standalone fixup?"
# User confirms → standalone mode

Result:

fixup! ✨ PAY-518 Return make, model and VIN in trim lookups

Standalone fixup
Remove duplicate flat attributes and encapsulate data
in PosSubModelNode for cohesion.