Lucas WintherandClaude Fable 5.2
edd57f0148
Audit pass: - Frame rule counts frames since the last move, so every step lasts exactly movesEvery(score) frames, also right after a speed-up - clampTime + MAX_GAP_MS: a hidden tab no longer replays the whole gap - Pong Restart keeps held keys - Fact corrections (mulberry32 output coverage, Haskell IO, uniform) - New fixture cases from a mutation analysis Extensions (all three tracks, shared fixtures, course text): - Turn queue (Exercise 10.6), persisted high score (10.7), replay viewer (10.8), play() end-to-end helper (9.5) - Optional State (4.7) and optional Module 7b, stack-safe IO - Module 12, property-based testing with generators, shrinking, invariants and a model-based oracle - Module 13, Conway's Life with a Click event - JS type checking via jsconfig, JSDoc and types.d.ts - Maintainer tools: scripts/mutate.mjs, scripts/typecheck-js.sh, Playwright end-to-end suite (e2e/, scripts/e2e.sh) Docs: docs/contract.md is the canonical contract; specs and build log under docs/superpowers. Verified: JS 728, Scala 689, F# 691 unit tests; stubs and progression M01-M13 and M07b; 176 end-to-end tests on Chromium and WebKit. Co-Authored-By: Claude Fable 5.2 <noreply@anthropic.com>
44 lines
1.8 KiB
JavaScript
44 lines
1.8 KiB
JavaScript
// m03 rules: the pure game rules. Each function takes a state and returns a new one.
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import { contains, dropLast } from './util.js'
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import { pointEquals, point, delta, opposite } from './model.js'
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/** @import { Point, Direction, GameState } from './types' */
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/** The cell one step from `p` in direction `dir`. No wrapping: it may land outside the board.
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* @type {(p: Point, dir: Direction) => Point} */
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export const move = (p, dir) => {
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const d = delta(dir)
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return point(p.x + d.x, p.y + d.y)
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}
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/** True if `p` lies on the board.
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* @type {(state: {width: number, height: number}, p: Point) => boolean} */
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export const inBounds = (state, p) => p.x >= 0 && p.x < state.width && p.y >= 0 && p.y < state.height
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/**
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* Ask to turn. We compare with `dir` (where the snake last moved), not `nextDir`:
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* otherwise Up-then-Left within one tick would turn a Right-moving snake back onto itself.
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* @type {(state: GameState, dir: Direction) => GameState}
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*/
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export const turn = (state, dir) =>
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state.status === 'Playing' && dir !== opposite(state.dir) ? { ...state, nextDir: dir } : state
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/** One step of the game.
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* @type {(state: GameState) => GameState} */
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export const advance = (state) => {
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if (state.status !== 'Playing') return state
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const d = state.nextDir
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const head = move(state.snake[0], d)
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const eating = state.apple !== null && pointEquals(head, state.apple)
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// When not eating, the tail leaves its cell this step, so the head may move into it.
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const body = eating ? state.snake : dropLast(state.snake)
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return !inBounds(state, head) || contains(body, head, pointEquals)
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? { ...state, dir: d, status: 'GameOver' }
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: {
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...state,
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snake: [head, ...body],
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dir: d,
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apple: eating ? null : state.apple,
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score: state.score + (eating ? 1 : 0),
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}
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}
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