Cursor rule

1---
2description: Rules for consistent and type-safe mocking in Vitest tests
3globs: "**/*.test.{ts,tsx,js,jsx}"
4alwaysApply: true
5---
6 
7# Spy Mocking Rules for Vitest Tests
8 
9## Mocking Approach
10 
11When mocking packages or files in Vitest-based tests, follow these rules:
12 
131. Use `vi.mock()` with the `spy: true` option for all package and file mocks
142. Place all mocks at the top of the test file before any test cases
153. Use `vi.mocked()` to type and access the mocked functions
164. Implement mock behaviors in `beforeEach` blocks
175. Mock all required dependencies that the test subject uses
18 
19## Mock Implementation Rules
20 
211. Mock implementations should be placed in `beforeEach` blocks
222. Each mock implementation should return a Promise for async functions
233. Mock implementations should match the expected return type of the original function
244. Use `vi.mocked()` to access and implement mock behaviors
255. Mock all required properties and methods that the test subject uses
26 
27## Avoided Patterns
28 
29The following mocking patterns should be avoided:
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311. Direct function mocking without `vi.mocked()`
322. Mock implementations outside of `beforeEach` blocks
333. Mocking without the `spy: true` option
344. Inline mock implementations within test cases
355. Mocking only a subset of required dependencies
36 
37## Best Practices
38 
391. Mock at the highest level of abstraction needed
402. Keep mock implementations simple and focused
413. Use type-safe mocking with `vi.mocked()`
424. Document complex mock behaviors
435. Group related mocks together
44