Implement effect-rstest: port of @effect/vitest to the Rstest runner

[ScriptedAlchemy]

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Summary

Implements effect-rstest, the Rstest equivalent of Effect's official @effect/vitest helpers for Effect v4. Ported from Effect commit 2600f62 (@effect/vitest@4.0.0-rc.112).

• Enhanced it with effect, live, layer, prop, and flakyTest
• Top-level effect, live, layer, prop, flakyTest, addEqualityTesters, makeMethods, and describeWrapped
• All runtime exports from @rstest/core
• Assertion helpers at effect-rstest/utils
• Ported upstream runtime and type tests running on rstest
• Publishable ESM package built with tsdown
• Strict publint validation in CI
• Independent pkg.pr.new canary workflow

Rstest-specific behavior

• Rstest has no public getCurrentSuite(). Unnamed layer(...)((it) => ...) blocks use an empty nested suite as their lifecycle boundary. Rstest omits the empty suite name from test paths, and the layer is released before subsequent tests in the enclosing suite. A regression test covers this boundary.
• describeWrapped returns void because Rstest's describe has no SuiteCollector; its wrapped global it registers in the active suite. A runtime test covers the enhanced API.
• skipIf / runIf conditions are coerced to boolean because Rstest types them as boolean rather than unknown.
• Effect test return values are ignored because Rstest callbacks require void / Promise<void>.
• The helper type namespace remains Vitest for source compatibility with the canonical package. This avoids shadowing and preserves the Rstest utility type re-exported from @rstest/core; a type test covers both.

Second-pass review fixes

• Fixed a real unnamed-layer leak: the previous enclosing-suite afterAll fallback left scoped resources alive for later sibling tests. The anonymous nested-suite fallback now matches upstream's release boundary.
• Restored the canonical Vitest helper namespace and the previously shadowed @rstest/core Rstest type export.
• Raised the @rstest/core peer floor from ^0.11.0 to ^0.11.11. Earlier allowed versions do not provide all APIs used by this port (TestContext.signal and exported TestAPIs).
• Added focused runtime tests for unnamed-layer release and describeWrapped, plus a type-level re-export regression test.

Reviewed and intentionally retained:

• src remains in files, matching upstream's distributed-source visibility; consumers resolve only the explicit dist exports.
• prepublishOnly: npm run build works under pnpm and also keeps direct npm publish safe; no package-manager-specific change is needed.
• ESM-only output is intentional.

Verification

Fresh local run after the review fixes:

• pnpm check — clean
• pnpm test — 3 files, 42 passed / 5 intentionally skipped (47 total)
• pnpm test:types — 8 tests, 9 assertions passed
• pnpm build — generated dist/index.mjs, dist/utils.mjs, and paired .d.mts declarations
• pnpm publint (--strict) — All good!

  

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Latest commit: e5f8d5f

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commit: e5f8d5f

[chatgpt-codex-connector]

Codex Review Summary

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Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-03T23:50:44.096871Z	e5f8d5f	Draft marked ready

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[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: e5f8d5f964

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[chatgpt-codex-connector]

Convert schemas before registering synchronous property tests

When it.prop receives any Schema—an input explicitly accepted by Vitest.Arbitraries and documented as supported—this throws during test-file collection instead of running the property. The object-arbitraries branch has the same behavior, so synchronous schema-based properties cannot be used; convert schemas with Schema.toArbitrary, as the effectful prop implementation already does.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Register the Effect equality tester

Calling the exported addEqualityTesters() currently adds an empty list and is therefore a no-op. Consumers relying on this API to make Rstest honor Effect's Equal semantics will still get ordinary structural equality, causing semantically equal Effect values to fail toEqual; pass the Effect equality tester to Rs.expect.addEqualityTesters instead.

Useful? React with 👍 / 👎.