assertRejects | /testing/asserts.ts | std@0.125.0 | Deno

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std/testing/asserts.ts>assertRejects

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function assertRejects

import { assertRejects } from "https://deno.land/std@0.125.0/testing/asserts.ts";

assertRejects<E extends Error = Error>(

fn: () => Promise<unknown>,

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

msgIncludes?: string,

msg?: string,

): Promise<void>

Executes a function which returns a promise, expecting it to throw or reject. If it does not, then it throws. An error class and a string that should be included in the error message can also be asserted. Or you can pass a callback which will be passed the error, usually to apply some custom assertions on it.

assertRejects(

fn: () => Promise<unknown>,

errorCallback: (e: Error) => unknown,

msg?: string,

): Promise<void>

assertRejects<E extends Error = Error>(

fn: () => Promise<unknown>,

errorClassOrCallback?: (new (...args: any[]) => E) | ((e: Error) => unknown),

msgIncludesOrMsg?: string,

msg?: string,

): Promise<void>

Executes a function which returns a promise, expecting it to throw or reject. If it does not, then it throws. An error class and a string that should be included in the error message can also be asserted. Or you can pass a callback which will be passed the error, usually to apply some custom assertions on it.

Type Parameters

optional

E extends Error = Error

Parameters

fn: () => Promise<unknown>

optional

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

optional

msgIncludes: string

optional

msg: string

Returns

Promise<void>

Parameters

fn: () => Promise<unknown>

errorCallback: (e: Error) => unknown

optional

msg: string

Returns

Promise<void>

Type Parameters

optional

E extends Error = Error

Parameters

fn: () => Promise<unknown>

optional

errorClassOrCallback: (new (...args: any[]) => E) | ((e: Error) => unknown)

optional

msgIncludesOrMsg: string

optional

msg: string

Returns

Promise<void>