testing

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name: testing description: Use this skill when writing or modifying test files in this project. Enforces Vitest as the framework, file-path mirroring (src/x.ts → tests/x.test.ts), describe/it structure, three minimum tests per function, and specific-value assertions over truthiness. paths:

• "*/.test.ts"
• "*/ test.ts"
• "tests/*/.ts"

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Testing Standards

Trigger

When writing or modifying test files.

##Instructions

• Framework: Vitest (import from 'vitest', not 'jest')
• Test file location: mirror source path src/utils/format.ts → tests/utils/format.test.ts
• Structure: describe() grouped by function, it for each case
• Naming: it(should [expected behavior] when [condition])
• Each function gets minimum 3 tests:

1. Happy path with typical input
2. Error/edge case (null, empty, boundary values)
3. Integration behavior (how it interacts with dependencies)

• Mock external dependencies with vi.mock()
• Never mock the function being tested
• Assert on specific values, not truthiness

Bad: expect(result).toBeTruthy()

Good: expect(result).toBe('validated')

• Use test.each() for parameterized tests with 3+ similar cases

##Constraints

• Do not import from 'jest' or '@jest/globals'
• Do not use snapshot tests unless explicitly asked
• Do not test private functions directly; test them through the public API