fix: guard against the script bootstrapping twice on a page#63
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When the userscript was injected more than once into the same page (re-injection
or a same-origin iframe), bootstrap ran twice and TheWestApi.register threw
"given parameter ('tw-calc') is already registered!" on the second run — the
visible symptom of everything initializing twice.
Extract the injection logic into src/inject.ts and skip bootstrapping when
window.TW_Calc is already set, making injection idempotent. Add tests for the
ready/already-injected guards.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Why
Reported in production:
Initializer.registerApi | given parameter ('tw-calc') is already registered!The game's
TheWestApi.register('tw-calc', …)throws when that key is already registered. Since the key is a constant, the only way to hit it is the script bootstrapping twice in the same window:index.tsstarts asetIntervalthat bootstraps once the game is ready, with no guard against the bundle being injected more than once (re-injection or a same-origin iframe). The register collision is the visible symptom of everything initializing twice.What
src/inject.tsand skip bootstrapping whenwindow.TW_Calcis already set, making injection idempotent. This fixes the root cause (all double-init), not just the API-register symptom.src/index.tsdown to wiring + theinject(...)call.Tests
New
inject.spec.ts(5 tests, driven with jasmine's clock): the game-ready guard, bootstraps exactly once when ready, and does not bootstrap again when already injected. Full suite green (npm test→ 18/18);tscandeslintclean.🤖 Generated with Claude Code