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Module

std/testing/asserts.ts>assertIsError

The Deno Standard Library
Latest
function assertIsError
Deprecated
Deprecated

This will be removed in 1.0.0. Import from https://deno.land/std/assert/assert_is_error.ts instead.

import { assertIsError } from "https://deno.land/std@0.224.0/testing/asserts.ts";

Make an assertion that error is an Error. If not then an error will be thrown. An error class and a string that should be included in the error message can also be asserted.

Examples

Example 1

import { assertIsError } from "https://deno.land/std@0.224.0/testing/asserts.ts";

assertIsError(null); // Throws
assertIsError(new RangeError("Out of range")); // Doesn't throw
assertIsError(new RangeError("Out of range"), SyntaxError); // Throws
assertIsError(new RangeError("Out of range"), SyntaxError, "Out of range"); // Doesn't throw
assertIsError(new RangeError("Out of range"), SyntaxError, "Within range"); // Throws

Type Parameters

optional
E extends Error = Error

Parameters

error: unknown
optional
ErrorClass: new (...args: any[]) => E
optional
msgMatches: string | RegExp
optional
msg: string

Returns

asserts error is E