Node.js assert.doesNotReject() Function
Last Updated :
14 May, 2022
Improve
The assert.doesNotReject() method is used to check if the given promise is not rejected. If the provided parameter is a Promise, it is awaited; if it is a function, it is called immediately and the returning Promise is awaited.
Syntax:
assert.doesNotReject(asyncFn[, error][, message])
Parameters:
- asyncFn: An asynchronous function or a Promise which is to be checked.
- error: It is the specified error. It might be a regular expression or a function. This is optional.
- message: The error message of string or error type. This is optional.
Return Value: It returns a rejected Promise.
Example 1:
import assert from 'node:assert/strict';
await assert.doesNotReject(
async () => {
await new Promise(resolve => setTimeout(resolve, 5000));
console.log("Hello");
},
SyntaxError
);
Output:
Hello
Example 2:
import assert from 'node:assert/strict';
function resolved(result) {
console.log('Resolved');
}
function rejected(result) {
console.error(result);
}
await assert.doesNotReject(
Promise.reject(new Error('fail')).then(resolved, rejected),
SyntaxError
);
Output:
Reference: https://nodejs.org/api/assert.html#assertdoesnotrejectasyncfn-error-message
