Finishing a Development Branch

# Finishing a Development Branch

## Overview

**Core principle:** Verify tests → Detect environment → Present options → Execute choice → Clean up.

**Announce at start:** "I'm using the finishing-a-development-branch skill to complete this work."

## Step 1: Verify Tests

Run the project's full test suite (`npm test` / `cargo test` / `pytest` / `go test ./...`).

**If tests fail**, report the failures and stop — the menu comes after a green suite:

```
Tests failing (<N> failures). Must fix before completing:

[Show failures]
```

**If tests pass:** continue to Step 2.

## Step 2: Detect Environment

```bash
GIT_DIR=$(cd "$(git rev-parse --git-dir)" 2>/dev/null && pwd -P)
GIT_COMMON=$(cd "$(git rev-parse --git-common-dir)" 2>/dev/null && pwd -P)
# Capture now, while still inside the workspace — Step 5 changes directory
# before cleanup (Step 6) needs this value
WORKTREE_PATH=$(git rev-parse --show-toplevel)
```

This determines which menu to show and how cleanup works:

| State | Menu | Cleanup |
|-------|------|---------|
| `GIT_DIR == GIT_COMMON` (normal repo) | Standard 3 options | No worktree to clean up |
| `GIT_DIR != GIT_COMMON`, named branch | Standard 3 options | Provenance-based (see Step 6) |
| `GIT_DIR != GIT_COMMON`, detached HEAD | Reduced 2 options (no merge) | Externally managed — leave in place |

## Step 3: Determine Base Branch

The base branch is whatever this work forked from — usually named in the