assert.doesNotReject

History

assert.doesNotReject(asyncFn, error?, message?): Promise

Attributes

asyncFn:Function | Promise

error:RegExp | Function

message:string

Returns:Promise

Awaits the asyncFn promise or, if asyncFn is a function, immediately calls the function and awaits the returned promise to complete. It will then check that the promise is not rejected.

If asyncFn is a function and it throws an error synchronously, assert.doesNotReject() will return a rejected Promise with that error. If the function does not return a promise, assert.doesNotReject() will return a rejected Promise with an ERR_INVALID_RETURN_VALUE error. In both cases the error handler is skipped.

Using assert.doesNotReject() is actually not useful because there is little benefit in catching a rejection and then rejecting it again. Instead, consider adding a comment next to the specific code path that should not reject and keep error messages as expressive as possible.

If specified, error can be a Class, RegExp or a validation function. See assert.throws() for more details.

Aside from asynchronously awaiting completion, it behaves identically to assert.doesNotThrow().

import assert from 'node:assert/strict';

await assert.doesNotReject(
  async () => {
    throw new TypeError('Wrong value');
  },
  SyntaxError,
);

JavaScript

const assert = require('node:assert/strict');

(async () => {
  await assert.doesNotReject(
    async () => {
      throw new TypeError('Wrong value');
    },
    SyntaxError,
  );
})();

JavaScript

import assert from 'node:assert/strict';

assert.doesNotReject(Promise.reject(new TypeError('Wrong value')))
  .then(() => {
    // ...
  });

JavaScript

const assert = require('node:assert/strict');

assert.doesNotReject(Promise.reject(new TypeError('Wrong value')))
  .then(() => {
    // ...
  });

JavaScript