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reviewing-unit-tests

Testing & Quality
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Use when reviewing Vitest unit-test diffs in ComfyUI_frontend, especially new mocks, store tests, component tests, or bugfix regression tests.

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Reviewing Unit Tests for ComfyUI_frontend

Overview

Review for behavior and current repo rules, not motion. Compare to authoritative rules, not prior diffs or legacy snippets.

Review Workflow

  1. Identify the test type: component, store, composable, util, or bugfix regression.
  2. Name the behavior the test proves. If you cannot say it in one sentence, request changes.
  3. Open the authoritative doc section before judging structure.
  4. Scan the red flags below.
  5. State the verdict first. Name the failure mode. Cite the doc or rule.

Source of Truth / Precedence

When docs and examples conflict, use this order:

  1. Explicit repo rules, lint rules, and note blocks.
  2. docs/testing/vitest-patterns.md
  3. Rule sections in docs/testing/unit-testing.md, docs/testing/store-testing.md, and docs/testing/component-testing.md
  4. Example snippets
  5. Prior diffs

Apply these repo-specific clarifications:

  • docs/testing/component-testing.md starts with the authoritative rule: new component tests use @testing-library/vue with @testing-library/user-event. The @vue/test-utils snippets below it are legacy examples.
  • docs/testing/store-testing.md still contains as any examples. Treat them as legacy snippets, not approval for new or edited test code.
  • If docs conflict, prefer the stricter newer rule and call out the doc ambiguity. Do not approve through it.
  • Motion != fix.

30-Second Red Flags

If you see...Failure modeDefault action
New @vue/test-utils import in a new component testlegacy test APIRequest changes
vi.mock('vue-i18n', ...)mocked i18nRequest changes
as any, @ts-expect-error, as Mock, as ReturnType<typeof vi.fn>, as unknown as Xunnecessary cast or type escapeRequest changes unless the author proves no safer type exists
getXMock(), renamed wrapper, or helper that only returns a mocked valuealias-by-renamingRequest changes
beforeEach recreates the return object for a module-mocked composable or serviceshared mock setup driftRequest changes
Assertions only check defaults, mock plumbing, or CSS hooksnon-behavioral testRequest changes
Bugfix test has no proof it fails on pre-fix codeunproven regressionRequest changes

Rationalization Table

ExcuseReality
"I restructured the mocks"If the indirection stayed, nothing improved. Flag alias-by-renaming.
"The docs do it"Rule, note, and lint beat legacy snippet. Compare to the current rule, not the nearest example.
"TypeScript required the cast"vi.mocked() usually narrows mock methods. Assertion-only references need no cast.
"Putting it in beforeEach is DRY"Recreating module mock state in hooks hides singleton behavior and drifts from the documented pattern.
"It is only a nit"Explicit repo-rule violations are never nits.
"No behavior changed, just cleanup"Motion != fix. Ask what behavior got stronger.
"Mental revert is enough"For bugfix tests, establish red on pre-fix code or ask the author to show it.

Mocking Rules

  • Fail helpers that do not remove repeated setup, encode domain meaning, or simplify assertions. Barely earning the abstraction is not enough.
  • For composables with reactive or singleton state, define stable mock state inside the vi.mock() factory. Access it per test via the composable itself. See docs/testing/unit-testing.md "Mocking Composables with Reactive State".
  • This does not ban local test data builders or per-test vi.spyOn(...).
  • Mock seams, not the project-owned module you are trying to exercise. For store tests, prefer real Pinia plus createTestingPinia({ stubActions: false }) per docs/testing/vitest-patterns.md and docs/testing/store-testing.md.

Alias-by-Renaming

// Before
const mockAdd = vi.hoisted(() => vi.fn())

// After: same indirection, new name
function getToastAddMock() {
  return useToast().add
}

If the wrapper only renames or relays a mocked value, fail it. Inline the lookup at the call site or fetch the singleton mock via the documented pattern.

vi.mocked() Scope

Use casevi.mocked() required?
.mockReturnValue, .mockResolvedValue, .mockImplementationYes
.mock.calls, .mock.resultsYes
expect(fn).toHaveBeenCalled()No
expect(fn).toHaveBeenCalledWith(...)No
  • Flag casts whenever vi.mocked() would narrow correctly.
  • Do not add vi.mocked() around assertion-only references just for style.

Reset Hygiene

  • Flag per-mock mockClear() or mockReset() when vi.clearAllMocks() or vi.resetAllMocks() already runs in the relevant hook chain.
  • Review for redundancy or broken state management. Do not bikeshed clearAllMocks vs resetAllMocks unless behavior depends on it.

Third-Party Seams

  • Distinguish trivial hooks from behavior-rich APIs.
  • Mocking single-method third-party hooks like primevue/usetoast is usually acceptable.
  • That exception does not justify mocking behavior-rich third-party modules.

vue-i18n

Test-Body Rules

SmellReview bar
Change-detector testReject. Default values alone prove nothing.
Mock-only assertionAccept collaborator-call assertions only when the call is the meaningful external effect and the test also exercises the triggering behavior.
Non-behavioral assertionReject tests that only check classes, utility hooks, or styling internals.
New component test using @vue/test-utilsRequest changes. Use @testing-library/vue plus @testing-library/user-event.
any, as any, or @ts-expect-error in new or edited test codeRequest changes unless the author proves no safer type exists. Legacy doc snippets do not authorize it.

Bugfix Regression Proof

For fix: PRs or bugfix diffs:

  1. Identify the production change that fixes the bug.
  2. Verify the new test fails on pre-fix code, or ask the author to show it.
  3. If the test passes on broken code, request changes.

A regression test that never proves red does not pin the bug.

Review Output Rules

  • State verdict before procedural questions.
  • Do not lead with approval language like LGTM, just one nit or approve and move on?.
  • Name the failure mode directly: alias-by-renaming, unnecessary cast, mocked i18n, mock-only assertion, unproven regression.
  • Link the authoritative doc section in the review comment.
  • If an explicit repo rule, lint rule, or authoritative doc note is violated, do not downgrade it to "minor deviation" or "nit".

Quick Reference

When you see...Read this
New vi.mock(...) for a composabledocs/testing/unit-testing.md -> "Mocking Composables with Reactive State"
New store test or store mockdocs/testing/vitest-patterns.md setup + docs/testing/store-testing.md
New component testTop note in docs/testing/component-testing.md
vue-i18n in a component testdocs/testing/vitest-patterns.md + src/components/searchbox/v2/__test__/testUtils.ts
Cast around a mockdocs/guidance/typescript.md -> "Type Assertion Hierarchy"

Key Files to Read

PurposePath
Composable mocking patternsdocs/testing/unit-testing.md
Store testing patternsdocs/testing/store-testing.md
Repo-wide Vitest setup defaultsdocs/testing/vitest-patterns.md
Component testing rule for new testsdocs/testing/component-testing.md
Real i18n setupsrc/components/searchbox/v2/__test__/testUtils.ts