throws

Summary

Asserts that fn throws. Optionally validates the thrown error against expectedError, which may be an Error constructor, an Error instance (matched by message), a RegExp (matched against the error message), a plain object (each property checked against the error, with RegExp values matching string properties), or a validator function that returns true for a valid error.

Signature

function throws(fn: () => unknown, expectedErrorOrMessage: unknown, message: AssertionMessage): void

Example

assert.throws(() => JSON.parse('invalid'))
assert.throws(() => riskyOp(), SyntaxError)
assert.throws(() => riskyOp(), { code: 'ERR_INVALID_ARG_VALUE' })

Parameters

fn

The function expected to throw.

expectedErrorOrMessage

Optional error constructor, instance, RegExp, object, validator, or failure message.

message

Optional failure message when expectedErrorOrMessage is an error matcher.