fix: resolve localStorage.clear crash in Vitest test suite for Node.js 20+ / Bun environments

[Itzzavdheshh]

Description

Fixes a critical test environment crash where the Vitest test suite failed entirely with TypeError: localStorage.clear is not a function.

Root Cause: Node.js 20+ and Bun expose a native but incomplete globalThis.localStorage that lacks standard Web Storage API methods like .clear(). This partial implementation clashes with jsdom's simulated storage, causing any test that calls localStorage.clear() to crash before assertions could run.

Fix: Updated vitest.setup.ts to detect when localStorage is missing or incomplete in the current environment. If so, a full in-memory mock is injected onto both window.localStorage and globalThis.localStorage, providing all standard methods: getItem, setItem, removeItem, clear, key, and length.

Result: All 121 tests across 13 test files now pass successfully. Previously, 7 tests were failing and the suite could not complete.

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Related Issue

Closes #1539 — Vitest Tests Fail to Run due to localStorage.clear Crash

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Type of Contribution

• Bug fix
• New feature
• Documentation update
• Refactor
• GSSoC contribution

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Participant Info

• GitHub username: @Itzzavdheshh
• Contribution level (Beginner/Intermediate/Advanced): Intermediate

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Screen Recording

How to record: run bun run dev → open http://localhost:3000 → demonstrate the full working flow of your change, including any edge cases.

• macOS: Cmd + Shift + 5 → Record Selected Portion, or use QuickTime Player
• Windows: Win + G → Xbox Game Bar → Capture
• Linux: OBS Studio, GNOME Screenshot tool, or kazam
• Any OS: [Loom](https://loom.com) (free screen recorder, great for sharing)

Recording / Loom link: — this is a test infrastructure fix with no UI changes. Terminal output showing 121/121 tests passing serves as verification.

test pass
https://drive.google.com/file/d/1iGlcNf_cSLxtVc9B3LYwhuTYOkdAeu_3/view?usp=sharing

webside view
https://drive.google.com/file/d/163aJfFGPaSK2dCtXJFh4X9T95dLuaVvj/view?usp=sharing

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Checklist

• I have read the contribution guidelines
• My changes follow the project structure
• I have tested my changes in Chrome, Firefox, and Safari
• bun run lint passes (no ESLint errors)
• bunx tsc --noEmit passes (no TypeScript errors)
• New interactive elements have aria-label / accessible names
• No console.log statements left in
• This PR is related to a valid issue
• Screen recording attached above (required for UI/feature/design changes)

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[Itzzavdheshh]

Hi @magic-peach 👋

I've been looking through the open issues and picked up Issue #1539 which was causing the entire Vitest test suite to crash with TypeError: localStorage.clear is not a function in Node.js 20+ and Bun environments. The fix is minimal and isolated to vitest.setup.ts only — no production code was touched. All 121 tests across 13 test files are now passing successfully, up from 114 passing with 7 failing before.

Please let me know if you'd like me to adjust the mock implementation, add comments to the setup file for clarity, or handle any edge cases I may have missed.

Happy to address any feedback required, Thank you! 🙏