Summary

The vitest/* plugin rules only fire when test functions (it, test, describe, expect, hooks, etc.) are imported from vitest (or aliased sources like vite-plus/test). They do not recognize @effect/vitest as a valid vitest import source, so 28 of the 35 rules I tested silently fail to fire on test files that import from it.

@effect/vitest is the official Effect testing integration: https://effect.website/docs/livesdk/testing/. It re-exports the entire vitest API (export * from "vitest") plus Effect-aware helpers (it.effect, it.live, layer(...), it.layer(...), it.effect.prop, etc.). It is the recommended way to test Effect code with Vitest, per the Effect testing guide.

Environment

• oxlint: bundled via vite-plus (@oxlint/[email protected], @oxlint/[email protected])
• Invoked via: vp lint (Vite+ CLI)
• @effect/vitest: 4.0.0-beta.83
• vitest: aliased to @voidzero-dev/vite-plus-test@latest via pnpm npm: override (a vitest fork) — same behavior reproduces with stock vitest

Reproduction

Two identical probe files, differing only in the import source:

// probe-effect.test.ts
import { describe, expect, it, test } from "@effect/vitest";

describe("probe", () => {
  test("mixed test and it usage", () => {}); // consistent-test-it should flag
  it("prefer-todo: empty body", () => {}); // prefer-todo + expect-expect should flag
  it("require-test-timeout: no timeout", () => {}); // require-test-timeout should flag
  it("prefer-strict-equal: uses toEqual", () => {
    // prefer-strict-equal should flag
    expect({ a: 1 }).toEqual({ a: 1 });
  });
  it.only("no-focused-tests: focused test", () => {}); // no-focused-tests should flag
  // ... plus cases for prefer-to-be, no-alias-methods, valid-expect, etc.
});

// probe-plain.test.ts  — identical body, different import
import { describe, expect, it, test } from "vitest";
// (same body as above)

Result

$ oxlint probe-effect.test.ts   # imports from @effect/vitest
Found 0 warnings and 0 errors.   # <- no vitest rules fire (only TS rules fire)

$ oxlint probe-plain.test.ts    # imports from vitest
Found 0 warnings and 102 errors. # <- 24 distinct vitest rules fire correctly

Rules affected

I tested 35 vitest rules with trigger cases. 28 silently fail to fire when the import source is @effect/vitest; 7 fire regardless of import source.

Silently broken on @effect/vitest (28)

These rules require resolving the import source to vitest and do not recognize @effect/vitest:

Work regardless of import source (7)

These appear to pattern-match on call syntax rather than resolving the import source, so they fire on both:

• vitest/no-conditional-in-test
• vitest/no-test-return-statement
• vitest/prefer-hooks-in-order
• vitest/prefer-mock-promise-shorthand
• vitest/prefer-mock-return-shorthand
• vitest/prefer-spy-on
• vitest/require-mock-type-parameters

Suggested fix

Treat @effect/vitest as a recognized vitest import source. Two possible approaches:

1. Hardcode @effect/vitest alongside vitest in the vitest plugin's import-source recognizer (smallest change).
2. Make it configurable — add an option like vitestImportSources: ["vitest", "@effect/vitest", ...] to the plugin config so projects can register additional re-exporting packages (more flexible; also covers vite-plus/test, private wrappers, etc.).

Option 2 would also resolve the related false-positive on vitest/no-importing-vitest-globals (which flags @effect/vitest imports as "global vitest functions" because it doesn't recognize the package as a valid vitest source). That rule currently has to be disabled in Effect projects, which then loses its protection on plain-vitest files in the same repo.

Related

• @effect/vitest package: https://github.com/Effect-TS/effect-smol/tree/main/packages/vitest
• Effect testing guide (recommends @effect/vitest as the entrypoint for all Effect tests): https://effect.website/docs/livesdk/testing/
• vitest/consistent-test-it rule docs: https://oxc.rs/docs/guide/usage/linter/rules/vitest/consistent-test-it.html