assertIsError | /assert/mod.ts | std@0.222.0

Module

std/assert/mod.ts>assertIsError

The Deno Standard Library

denoland/deno_std

Go to Latest

mod.ts (default module)

assertNotStrictEquals

assert_almost_equals.ts

assertAlmostEquals

assert_array_includes.ts

assert_greater_or_equal.ts

assertGreaterOrEqual

assert_greater.ts

assertGreater

assert_instance_of.ts

assert_less_or_equal.ts

assert_not_instance_of.ts

assertNotInstanceOf

assert_not_match.ts

assertNotMatch

assert_not_strict_equals.ts

assertNotStrictEquals

assert_object_match.ts

assertObjectMatch

assert_rejects.ts

assertRejects

assert_strict_equals.ts

assertStrictEquals

assert_string_includes.ts

The Standard Library has been moved to JSR. See the blog post for details.

function assertIsError

Re-export

import { assertIsError } from "https://deno.land/std@0.222.0/assert/mod.ts";

assertIsError<E extends Error = Error>(

error: unknown,

ErrorClass?: new (...args: any[]) => E,

msgMatches?: string | RegExp,

msg?: string,

): asserts error is E

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@0.222.0/assert/assert_is_error.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