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Vitest · Matcher

toBeString

Vitest's expectTypeOf checks TypeScript types at compile time. Use it in type tests to verify exact types, assignability, properties, function parameters, arrays, and promise results.

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Syntax

<T>(a: unknown) => ExpectTypeOf

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  • toEqualTypeOf
  • toExtend
  • toHaveProperty
  • items
  • resolves
  • toBeCallableWith
  • assertType

Source: expectTypeOf | Vitest. Checked 2026-11-03.