Jasmine & Karma

What is Jasmine?

Jasmine is a testing framework.

👉 It is used to:

• Write test cases
• Describe test behavior in readable English
• Provide assertions (expectations)

Jasmine gives you:

• describe() → test suite
• it() → test case
• expect() → assertion
• Spies (spyOn) → mock functions

What is Karma?

Karma is a test runner.

👉 It is used to:

• Run the Jasmine tests
• Launch browsers (Chrome, Headless Chrome, Firefox)
• Watch files and re-run tests automatically
• Show test results

Karma does not write tests. It only executes them.

Interview line:

Karma runs the tests written using Jasmine in real browsers.

How they work together (important)

Angular Code ↓ Jasmine (writes tests) ↓ Karma (runs tests in browser) ↓ Test Results

Angular context (very important for interviews)

• Angular CLI comes with Jasmine + Karma by default
• ng test:
• Uses Karma
• Executes Jasmine tests
• Runs tests in real browser environment

One-paragraph interview answer (use this 🔥)

Jasmine is a testing framework used to write unit tests with readable syntax and assertions. Karma is a test runner that executes these Jasmine tests in real browsers, watches file changes, and reports results. In Angular, Jasmine and Karma work together to provide a complete unit testing setup.

❓ Can Karma work without Jasmine?

➡️ Yes, Karma can run tests written in Jest, Mocha, etc.