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Jest · Matcher

toBeDefined

Jest's toBeDefined matcher checks that a value is not undefined. Use it when a function or expression should produce a defined result.

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Syntax

expect(value).toBeDefined()

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  • expect(value)
  • toBeUndefined
  • toBeNull
  • toBeTruthy
  • toBeFalsy

Source: Using Matchers · Jest. Checked 2026-11-03.