Beginner LevelNode JS
How do you write zero-dependency assertions using the node:assert module?
❓ Interview Prompt: Explain `node:assert` module, strict mode (`assert.strict`), `strictEqual`, `deepStrictEqual`, and `rejects`.
The native 'node:assert' module provides zero-dependency assertion testing capabilities:
•
'assert.strictEqual(actual, expected)': Checks equality with '==='.
•
'assert.deepStrictEqual(a, b)': Recursively checks object/array structure equality.
•
'assert.rejects(promise)': Asserts that an asynchronous Promise rejects.
Code Implementation Example
javascript
import assert from 'node:assert/strict';
// Strict equality assertion
assert.strictEqual(2 + 2, 4);
// Deep object structural assertion
assert.deepStrictEqual(
{ user: 'Alice', roles: ['admin'] },
{ user: 'Alice', roles: ['admin'] }
);
console.log('All assertions passed!');💡Writing strict unit test assertions using node:assert/strict.
🎯 Interview Key Takeaway
Use node:assert/strict for zero-dependency unit testing assertions in Node.js.
#assert#Testing#Unit Tests#Beginner
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