024-snake/docs/milestones/mil-003-continuous-play-and-high-score.md

MIL-003: Continuous play and high score

Metadata

Key	Value
ID	MIL-003
CrossReference	BC-001
Language	en
Domain	it

Version History

Date	Status	Author	Reviewer	Change	Commit
2026-10-13	Accepted	Jens Tirsvad Nielsen	AI as stand-in for S01	Initial version, reviewed in RC-006 (Go)	e004c34

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Purpose

This gate decides whether the game follows the day-24 lectures on the high score and on continuous play: the scoreboard has a high_score, reset replaces game_over, a collision resets the snake and the score and the game goes on, and the old snake leaves the screen. The high score lives in memory only; the lecture itself shows that it is lost when the game is started again, and MIL-004 stores it. The work is delivered on the branch mil-003-continuous-play-and-high-score and one pull request.

Deliverable

Changed src/snake_game/scoreboard.py, snake.py, main.py and constants.py, with changed and added tests. Scoreboard.game_over and its test are removed; Scoreboard.reset and Snake.reset are added.

Go / No-Go Criteria

#	Criterion (objectively checkable)	Go	No-Go
1	The scoreboard shows both scores	The text is Score: <score> High Score: <high_score> and starts as Score: 0 High Score: 0; the label texts are constants; the old text is cleared before every write	A different text, a literal label outside constants.py, or text that is written over the old one
2	Scoreboard.reset follows the lecture	When score > high_score, high_score becomes the score; then the score is 0 and the scoreboard is written again; a lower or equal score leaves high_score unchanged	Any of the three cases behaves differently
3	Snake.reset clears the old snake	Every old segment is sent to a place off the screen (a constant), segments is emptied, the snake is created again at the three starting positions and head is the first new segment	An old segment stays on the screen, or head still refers to an old segment
4	A collision no longer ends the game	At the wall and at the tail, scoreboard.reset() and snake.reset() are called and the loop goes on; game_over, GAME_OVER_TEXT and the wait for a click are gone	The game stops, or a name of the removed game over remains
5	The snake is playable after a reset	After a reset the snake moves right from the starting positions, a reversal is still ignored, and the food keeps its place	The snake does not move, or turns back onto itself
6	The day-24 values are constants	The off-screen place and the label texts used by reset and the scoreboard are constants with Doxygen comments	A literal in another module
7	The day-21 tests still hold	Every test of MIL-002 passes, or is changed on purpose and the change is named in the pull request	A test is deleted without being named
8	Tests, lint, format and types are clean	pytest, python -m ruff check src tests, python -m ruff format --check src tests and python -m mypy exit 0, as in continuous integration (CI); no test opens a window	Any of them fails
9	doxygen Doxyfile builds	0 warnings	Any warning
10	The game can be played	S01 plays in Windows PowerShell: hits the wall and the tail twice, sees the score go back to 0, the high score keep the best, and the old snake disappear	Any of those does not happen
11	The code is reviewed	RC-* against QC-PY-001 has the verdict Go	Verdict No-Go or Go-with-conditions
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-002 accepted and merged	The classes and the main flow that this milestone changes exist there

Traceability

Business Case objective / KPI / user story	Reference
Objective 2: the high score and the scoreboard text	BC-001, criterion 2 in Success Criteria
Objective 3: continuous play and reset	BC-001, criterion 3 in Success Criteria
Objective 4: Snake.reset	BC-001, criterion 3 in Success Criteria
Objective 7: the assignment's names	BC-001, criterion 10 in Success Criteria

Ownership

Role	Stakeholder ID (SA)
Owner	S01
Approving reviewer	S01

Target Date

2026-10-19 — third of five gateways.

Tasks

#	Task	Summary	Needs its own Use Case/User Story?	Reference
1	Add the high score constants	Add to constants.py, with Doxygen comments: the label of the high score text, the place off the screen where an old segment is sent, and any other value the next tasks need. Add the matching test of test_constants.py.	No
2	Add the high_score attribute and the scoreboard text	Scoreboard.__init__ sets self.high_score to 0 next to self.score; update_scoreboard clears the old text and writes Score: <score> High Score: <high_score>; tests with the fake turtle check the text and the clearing.	No
3	Replace game_over with reset in the Scoreboard	Remove Scoreboard.game_over and its test. Add Scoreboard.reset: when the score is higher than high_score, the high score becomes the score; the score becomes 0; update_scoreboard is called. Tests: higher, equal and lower score.	No
4	Add Snake.reset	Add Snake.reset: send every segment of segments to the off-screen place, empty the list, call create_snake again and set head to segments[0]. Tests with fake segments check that no old segment remains and that the starting positions are used.	No
5	Play on after a collision in the main flow	In main.py, a hit of the wall or of the tail calls scoreboard.reset() and snake.reset() and the loop goes on; the end-of-game check, the game-over text and exitonclick are removed; closing the window still ends quietly. Update tests/test_main.py.	No
6	Update the README for continuous play	Describe in the Run section the two scores on the scoreboard and what a collision does now, and remove the sentences about game over. Serves S02 and S03.	No
7	Verify continuous play end to end	Run pytest, ruff check, ruff format --check, mypy and doxygen Doxyfile in a fresh .venv, play with several collisions and close the window, and record the results and the changed tests in the pull request.	No

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