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JavaScript API

jslib

k6-testing

Non-Retrying Assertions

toBeNull()

Open source

toBeNull()

The toBeNull() method asserts that a value is exactly null.

Syntax

expect(actual).toBeNull();
expect(actual).not.toBeNull();

Returns

Type	Description
void	No return value

Description

The toBeNull() method checks if a value is exactly null. It only passes for the null value and fails for all other values, including undefined, false, 0, and empty strings.

Usage

import http from 'k6/http';
import { expect } from 'https://jslib.k6.io/k6-testing/0.6.1/index.js';

export default function () {
  const response = http.get('https://quickpizza.grafana.com/');

  // Check for null values in response
  const maybeNull = null;
  if (maybeNull === null) {
    expect(maybeNull).toBeNull();
  }

  // Check that required fields are not null
  expect(response.body).not.toBeNull();
  expect(response.status).not.toBeNull();

  // Basic null checks
  expect(null).toBeNull();
  expect(undefined).not.toBeNull();
  expect(false).not.toBeNull();
  expect(0).not.toBeNull();
}