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What is the built-in node:test runner and how does it compare to Jest and Mocha?

Q: What is the built-in node:test runner and how does it compare to Jest and Mocha?

**TL;DR.** node:test is Node's **built-in** test runner (stable since Node 20): no dependencies, parallel file execution, and bundled node:assert , **mocking**, and --experimental-test-coverage . Jest/Mocha add richer ecosystems (snapshots, watch UIs, huge plugin sets) at the cost of install size and config. node:test zero deps, built-in assert + mock + coverage Jest / Mocha rich plug

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Node's native test runner, its API, and trade-offs vs Jest/Mocha.

nodejstestingnode-testtooling

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A node:test with mock + coverage

import { test, mock } from 'node:test';
import assert from 'node:assert/strict';

test('sends one email', () => {
  const send = mock.fn();
  notify({ send }, 'hi');
  assert.equal(send.mock.callCount(), 1);
});
// run:  node --test --experimental-test-coverage

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