021-snake-game/docs/sqa/reviews/rc-008-mil-002-code.md

RC-008: Review of the MIL-002 code

Metadata

Key	Value
ID	RC-008
CrossReference	MIL-002, QC-PY-001, BC-001, PP-001

Version History

Date	Status	Author	Reviewer	Change	Commit
2026-10-08	Proposed	Jens Tirsvad Nielsen	S01	Initial version	pending

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Artifact Under Review

• Instance reviewed: MIL-002 tasks 1 to 5: src/snake_game/snake.py, food.py, scoreboard.py, main.py, __main__.py and the tests tests/fakes.py, test_snake.py, test_food.py, test_scoreboard.py, test_main.py
• Checklist used: QC-PY-001
• Scope: full review. constants.py and test_constants.py were reviewed in RC-007. The files are byte-identical to the base (020-snake-game, commit 1a638c9), checked with cmp for all ten files, so the review reads them as adopted code and does not ask for changes that the base does not have.
• Language and domain: n/a (technical type)
• Language reviewer: none

Checklist Results

#	Criterion	Status	Evidence/Notes
1	Packages, modules, functions, variables, classes and constants follow PEP 8 casing (snake_case, PascalCase, UPPER_SNAKE)	Pass	Classes Snake, Food, Scoreboard, Segment, ScreenLike, FoodLike, ScoreboardLike in PascalCase; functions and methods in snake_case; constants in UPPER_SNAKE; the ruff N (pep8-naming) rules pass.
2	Names state purpose in the domain's language; no unexplained abbreviations, no single-letter names outside tiny scopes	Pass	Names are the lecture's and the dictionary's: create_snake, add_segment, extend, hits_wall, hits_tail, refresh, increase_score, update_scoreboard, game_over, eat_food_if_close, end_game_if_over, game_is_on. The same names appear in DICT-001. The only single-letter names are the parameters x and y of goto and distance in the Segment protocol, which mirror the turtle API (found with an AST search).
3	Code is produced by the project's formatter and passes its linter with no unexplained suppressions	Pass	ruff format --check src tests reports 13 files already formatted; ruff check src tests reports all checks passed (rules E, F, W, I, N, UP, B, SIM); a search found no noqa and no type: ignore.
4	Every function and method signature is type-annotated, including -> None	Pass	mypy in strict mode reports no issues in 13 source files, which fails on an unannotated definition. Protocols (Segment, ScreenLike, FoodLike, ScoreboardLike) type the turtle objects so that the logic can take fakes.
5	No bare except:, no swallowed exceptions; specific exceptions are raised and the cause is kept (raise ... from)	Pass	The only handler is except (Terminator, TclError) in main.main. It names two specific types, catches an external signal that the player closed the window, is explained in the docstring and in a comment, and a test covers the quiet exit. Nothing is raised, so there is no cause to keep. The convention warns against exceptions as normal control flow; here the window toolkit raises them, so S01 may want to confirm the decision.
6	No mutable default arguments and no shadowed builtins	Pass	The only default argument is `segment_factory: ...
7	Files, locks and connections are managed with context managers	N-A	The modules open no file, lock or connection.
8	Public modules, classes and functions have docstrings that say what, not how	Pass	Every module, class, function and method has a Doxygen docstring or ## comment; doxygen Doxyfile ends with 0 warnings (the Doxyfile fails the build on any warning).
9	Logging uses logging, not print; no secrets or personal data in log output	Pass	A search found no print and no logging in src; the token values of .env occur in no tracked file.
10	Classes and operations trace to the Design Class Diagram they implement; deviations are recorded	Pass	No Design Class Diagram exists in this project; the classes and operations trace to the day-21 lectures, to the base and to tasks 2 to 5 of MIL-002. The deviation is recorded in the Traceability section of MIL-002.
11	Tests exist for new behaviour, are named for the behaviour, and do not depend on order or the network	Pass	pytest runs 128 tests (91 test functions, some parametrized), all green, none opens a window. The fake turtle and tkinter modules are installed with monkeypatch.setitem, which pytest undoes after each test. Each test file passes alone, and all files pass in reverse order. One test starts a fresh interpreter to prove that importing main loads no display module; it uses no network.
12	Type checker runs in strict mode without errors; Any is justified in a comment	Pass	strict = true; python -m mypy ends with "Success: no issues found in 13 source files". Any occurs only as the return type of make_food and make_scoreboard in tests/fakes.py, each with a docstring that says why.
13	Dependencies are declared and pinned in the project's dependency file, none unused	Pass	No new dependency: the code uses the standard library only (random, time, turtle, tkinter, typing, collections.abc). The dev extra is as reviewed in RC-007.

Overall Verdict

Go — all Mandatory criteria pass; criterion 7 is N-A because no module opens a file, lock or connection. Commands run on 2026-10-08 in the .venv in Windows PowerShell: pytest (128 passed), ruff check, ruff format --check, mypy, doxygen Doxyfile (0 warnings). The assistant also started python -m snake_game twice and closed its window, once after about 2 seconds (during play) and once after about 5 seconds, by which time a snake moving right should have passed the wall: both ended with exit code 0 and an empty error output. The window title was "My Snake Game". The game-over text was not seen. That is a smoke test, not the manual play that MIL-002 criterion 5 asks of S01. This review is not independent: the assistant that adopted the code also reviewed it, and author and reviewer (S01) are one person in a single-person project (risk recorded in BC-001 and PP-001). S01 can overrule this verdict at the pull request.

Action Items

Action	Owner	Due
Play the game in Windows PowerShell and confirm MIL-002 criterion 5 (moves, turns, food, growth, score, wall, tail)	S01	2026-10-12
Read the MIL-002 code and the list of differences from the base (none), and confirm or overrule this Go before the pull request is merged	S01	2026-10-12
Confirm that catching Terminator and TclError to end quietly when the window is closed is acceptable (criterion 5)	S01	2026-10-12

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