# Implementation Plan: Clean Install Test (clean_install_test_20260603)

## Phase 1: Add pytest marker [checkpoint: 573d289]
Focus: Register the `clean_install` marker in `pyproject.toml` so the test can be selected with `pytest -m clean_install` or filtered with `-m "not clean_install"`.

- [x] Task 1.1: Pre-edit checkpoint - `git add .`
- [x] Task 1.2: Edit `pyproject.toml` to add `clean_install` marker
- [x] Task 1.3: Run `pytest --collect-only` to confirm marker is recognized
- [x] Task 1.N: Atomic commit + git note (573d289)

## Phase 2: Create the test file [checkpoint: d171c18]
Focus: Create `tests/test_clean_install.py` with opt-in clone-and-verify logic.

- [x] Task 2.1: Pre-edit checkpoint - `git add .`
- [x] Task 2.2: Create `tests/test_clean_install.py` using `urllib.request` (deviation from plan, see spec.md)
- [x] Task 2.3: Run the test in skip mode - should be 1 skipped
- [x] Task 2.N: Atomic commit + git note (d171c18)

## Phase 3: Phase Completion Verification
- [x] Task 3.1: Run the test in default mode - 1 skipped (gating works)
- [x] Task 3.2: `pytest --collect-only -m clean_install` confirms marker works
- [x] Task 3.3: Negative marker filter works (-m "not clean_install" deselects the test)
- [x] Task 3.4: Module imports cleanly
- [x] Task 3.N: conductor(checkpoint) commit + audit note
