021-snake-game/docs/milestones/mil-002-adopt-the-game.md

MIL-002: Adopt the game

Metadata

Key	Value
ID	MIL-002
CrossReference	BC-001
Language	en
Domain	it

Version History

Date	Status	Author	Reviewer	Change	Commit
2026-10-08	Accepted	Jens Tirsvad Nielsen	S01	Initial version, reviewed in RC-005 (Go)	pending

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Purpose

This gate decides whether the finished game of the base (020-snake-game, main) runs in this repository: the snake, the food, the scoreboard, the main flow and all their tests are here, they pass, and the game can be played. It does not yet compare the game with the day-21 lectures; that is MIL-003. The work is delivered on the branch mil-002-adopt-the-game and one pull request.

Deliverable

src/snake_game/snake.py (the class Snake), src/snake_game/food.py (the class Food), src/snake_game/scoreboard.py (the class Scoreboard), src/snake_game/main.py and src/snake_game/__main__.py (the main flow and python -m snake_game), and the tests tests/fakes.py, tests/test_snake.py, tests/test_food.py, tests/test_scoreboard.py and tests/test_main.py. Running python -m snake_game plays the whole game.

The files are copied from the base and changed only where the identity of this repository requires it. The module split of the base is kept: the lecture's single script is already divided into Snake, Food, Scoreboard and a main flow, and the main flow keeps the lecture's names (screen, snake, food, scoreboard, game_is_on). The pull request lists every difference from the base.

Go / No-Go Criteria

#	Criterion (objectively checkable)	Go	No-Go
1	The adopted files match the base	The pull request lists every difference between each adopted file and the base, or says that there is none	A difference that the list does not name
2	All tests pass without a display	pytest exits 0; no test opens a window; every test of the base is present	A failing test, or a test of the base is missing
3	Lint, format and types are clean	python -m ruff check src tests, python -m ruff format --check src tests and python -m mypy exit 0, as in continuous integration (CI)	Any of the three fails
4	doxygen Doxyfile builds	0 warnings	Any warning
5	The game can be played	S01 runs python -m snake_game in Windows PowerShell: the window opens, the snake moves and turns, food is shown, the snake eats and grows, the score rises, and the game ends at the wall and at the tail	The game does not start, or one of those things does not happen
6	Closing the window ends quietly	Closing the window during play, and after game over, ends the program with exit code 0 and no traceback	A traceback
7	Importing the main flow needs no display	Importing snake_game.main loads neither turtle nor tkinter	Either module is loaded by the import
8	The assignment's names exist	Every name of objective 5 of BC-001 exists with that spelling	A name is missing or spelled differently
9	Constants are in one place	No module other than constants.py defines a value of the lectures	A value is a literal in another module
10	The code is reviewed	RC-* against QC-PY-001 has the verdict Go	Verdict No-Go or Go-with-conditions
11	The README matches the adopted game	The Run section and the Project layout of README.md describe the files and the command of this milestone, and no sentence says that the game is still to come	A sentence that is out of date, or a file or command that the README does not name
12	No secret is in the change	.env is not tracked and no token appears in any changed file	A token is found in the diff

Dependencies

Depends on	Reason
MIL-001 accepted and merged	The package, constants.py, the test set-up, the Doxyfile and the CI workflow exist there

Traceability

Business Case objective / KPI / user story	Reference
Objective 1: the day-20 behaviour is kept	BC-001, criterion 1 in Success Criteria
Objectives 2 and 3: food, eating, score and game over	BC-001, criteria 2 and 3 in Success Criteria
Objective 4: inheritance and slicing	BC-001, criterion 4 in Success Criteria
Objective 5: the assignment's names	BC-001, criterion 9 in Success Criteria
Objective 7: tests without a display	BC-001, criterion 5 in Success Criteria
Objective 8: Doxygen and README	BC-001, criterion 7 in Success Criteria
Objective 9: traceable steps; the base is adopted without hidden change	BC-001, criteria 10 and 12 in Success Criteria
Design of Snake, Food, Scoreboard and the main flow: no Design Class Diagram exists in this project and none is wanted for a learning project of this size. The classes trace to the day-21 lectures, to the base and to tasks 2 to 5 below. This is a recorded deviation from QC-PY-001 criterion 10, as in the base	PP-001

Ownership

Role	Stakeholder ID (SA)
Owner	S01
Approving reviewer	S01

Target Date

2026-10-12 — second of three gateways, inside the one-week plan of PP-001 that ends 2026-10-16.

Tasks

#	Task	Summary	Needs its own Use Case/User Story?	Reference
1	Adopt the test fakes	Copy tests/fakes.py from the base: the fake segment, the fake screen and the fake Turtle base class that record their calls, so that every test runs without a display. The fake turtle module is installed before food and scoreboard are imported, because a class that inherits from Turtle needs the module at import time. List every difference from the base in the pull request.	No
2	Adopt the Snake class and its tests	Copy src/snake_game/snake.py and tests/test_snake.py from the base: create_snake, add_segment, extend, move, hits_wall, hits_tail, up, down, left, right, the segments list and the head. The tail check loops over the slice segments[1:]. snake.py does not import turtle until a real segment is made, so the tests pass fakes.	No
3	Adopt the Food class and its tests	Copy src/snake_game/food.py and tests/test_food.py from the base: class Food(Turtle), whose __init__ calls super().__init__() and refresh, and whose random place comes from one function that the tests replace. The values are checked against the lectures in MIL-003.	No
4	Adopt the Scoreboard class and its tests	Copy src/snake_game/scoreboard.py and tests/test_scoreboard.py from the base: class Scoreboard(Turtle) with update_scoreboard, increase_score and game_over. The values are checked against the lectures in MIL-003.	No
5	Adopt the main flow and the entry point	Copy src/snake_game/main.py, src/snake_game/__main__.py and tests/test_main.py from the base: the screen set-up, the key bindings, the animation loop with game_is_on, the eating check, the game-over check, the wait for a click and the quiet exit when the window is closed. main imports food and scoreboard only when it runs, so importing it needs neither turtle nor tkinter.	No
6	Describe the adopted game in the README	Update the Run section and the Project layout of README.md so that they match the files and the command of this milestone (python -m snake_game, the modules of src/snake_game/, the tests), and remove the sentence that says the game is still to come. MIL-003 finishes the README for the whole game. Serves S02 and S03.	No
7	Verify the adopted game end to end	Run pytest, ruff check, ruff format --check, mypy and doxygen Doxyfile in a fresh .venv, run python -m snake_game and play it until the game is over, close the window during play, and record the results and the list of differences from the base in the pull request.	No

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