import { assertRejects } from "https://deno.land/std@0.196.0/testing/asserts.ts";
Executes a function which returns a promise, expecting it to reject.
Examples
Example 1
Example 1
import { assertRejects } from "https://deno.land/std@0.196.0/assert/assert_rejects.ts";
Deno.test("doesThrow", async function () {
await assertRejects(
async () => {
throw new TypeError("hello world!");
},
);
await assertRejects(
async () => {
return Promise.reject(new Error());
},
);
});
// This test will not pass.
Deno.test("fails", async function () {
await assertRejects(
async () => {
console.log("Hello world");
},
);
});
Executes a function which returns a promise, expecting it to 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.
Examples
Example 1
Example 1
import { assertRejects } from "https://deno.land/std@0.196.0/assert/assert_rejects.ts";
Deno.test("doesThrow", async function () {
await assertRejects(async () => {
throw new TypeError("hello world!");
}, TypeError);
await assertRejects(
async () => {
throw new TypeError("hello world!");
},
TypeError,
"hello",
);
});
// This test will not pass.
Deno.test("fails", async function () {
await assertRejects(
async () => {
console.log("Hello world");
},
);
});
Parameters
ErrorClass: new (...args: any[]) => E