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react19-test-patterns

Provides before/after patterns for migrating test files to React 19 compatibility, including act() imports, Simulate removal, and StrictMode call count changes.

skills/react19-test-patterns/SKILL.md

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# React 19 Test Migration Patterns

Reference for all test file migrations required by React 19.

## Priority Order

Fix test files in this order; each layer depends on the previous:

1. **`act` import**  fix first, it unblocks everything else
2. **`Simulate` → `fireEvent`**  fix immediately after act
3. **Full react-dom/test-utils cleanup**  remove remaining imports
4. **StrictMode call counts**  measure actual, don't guess
5. **Async act wrapping**  for remaining "not wrapped in act" warnings
6. **Custom render helper**  verify once per codebase, not per test