test(react-grab): unit-test Next runtime detection + base path

[aidenybai]

Summary

The e2e coverage run skips the Next fixture, leaving these document-driven helpers structurally untested (is-next-project-runtime.ts ~20%, get-next-base-path.ts via the next-server-frames path always hit the empty branch). Tested in isolation in node with a stubbed document.

• is-next-project-runtime.ts: __NEXT_DATA__ (Pages Router) and nextjs-portal (App Router dev overlay) detection, the no-document and no-marker negatives, and the memoize/shouldRevalidate cache contract.
• get-next-base-path.ts: the configured-basePath prefix (/app/_next/… → /app), the root /_next/ and missing-script empty cases, and first-call memoization. Each branch re-imports a fresh module via vi.resetModules() since the module-level cache has no reset hook.

Test plan

• pnpm test:unit — 98 passed (was 89)
• pnpm typecheck clean
• pnpm lint clean
• pnpm format:check — only flags pre-existing core/index.tsx (untouched)

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Note

Low Risk
Test-only changes with no production code modifications.

Overview
Adds unit tests only for two DOM-dependent Next.js helpers that were lightly covered because e2e skips the Next fixture.

is-next-project-runtime: stubs document to assert Pages Router (__NEXT_DATA__) and App Router dev overlay (nextjs-portal) detection, no-document/no-marker negatives, and memoization until shouldRevalidate clears the cache.

get-next-base-path: stubs a /_next/ script src to assert configured basePath prefix extraction, root and missing-script empty results, and first-call memoization. Tests use vi.resetModules() and fresh dynamic imports because the module cache has no reset hook.

^{Reviewed by Cursor Bugbot for commit 5ddaa05. Bugbot is set up for automated code reviews on this repo. Configure here.}

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Summary by cubic

Add unit tests for is-next-project-runtime and get-next-base-path in react-grab, using a stubbed document to run in Node. Covers Pages/App Router markers, no-document/no-marker and missing-script cases, basePath extraction (including root /_next/), and memoization/revalidation behavior.

^{Written for commit 5ddaa05. Summary will update on new commits.}

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Project	Deployment	Actions	Updated (UTC)
react-grab-storybook	Ready	Preview, Comment	Jun 28, 2026 11:20am
react-grab-website	Ready	Preview, Comment	Jun 28, 2026 11:20am

[pkg-pr-new]

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commit: 5ddaa05

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}

[aidenybai]

Superseded by #510, which consolidates all the test-coverage PRs into one. Commits preserved there.