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assert.fail - assert - Node documentation
function assert.fail

Usage in Deno

import assert from "node:assert";
fail(message?: string | Error): never

Throws an AssertionError with the provided error message or a default error message. If the message parameter is an instance of an Error then it will be thrown instead of the AssertionError.

import assert from 'node:assert/strict';

assert.fail();
// AssertionError [ERR_ASSERTION]: Failed

assert.fail('boom');
// AssertionError [ERR_ASSERTION]: boom

assert.fail(new TypeError('need array'));
// TypeError: need array

Using assert.fail() with more than two arguments is possible but deprecated. See below for further details.

Parameters

optional
message: string | Error = 'Failed'

Return Type

never
fail(
actual: unknown,
expected: unknown,
message?: string | Error,
operator?: string,
stackStartFn?: Function,
): never
Deprecated

since v10.0.0 - use fail([message]) or other assert functions instead.

Parameters

actual: unknown
expected: unknown
optional
message: string | Error
optional
operator: string
optional
stackStartFn: Function

Return Type

never
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