---
id: LambdaTest/agent-skills/jasmine-skill
version: "97de3841"
license: MIT
install: manual
updated: 2026-07-24
---

# jasmine-skill — jasmine-skill enables you to craft well-organized unit tests following Jasmine's behavior-driven development patterns. Use describe blocks to group related tests, it blocks to define individual test cases, and expect assertions to validate your code's behavior. Perfect for developers building robust test suites with clear, readable test structure.

Publisher: LambdaTest · Stars: 339 · Updated: 2026-07-24

Install (manual): `git clone https://github.com/LambdaTest/agent-skills`

## SKILL.md

# Jasmine Testing Skill

## Core Patterns

### Basic Test

```javascript
describe('Calculator', () => {
  let calc;

  beforeEach(() => { calc = new Calculator(); });

  it('should add two numbers', () => {
    expect(calc.add(2, 3)).toBe(5);
  });

  it('should throw on divide by zero', () => {
    expect(() => calc.divide(10, 0)).toThrowError('Division by zero');
  });
});
```

### Matchers

```javascript
expect(value).toBe(exact);              // === strict
expect(value).toEqual(object);           // Deep equality
expect(value).toBeTruthy();
expect(value).toBeFalsy();
expect(value).toBeNull();
expect(value).toBeUndefined();
expect(value).toBeDefined();
expect(value).toBeNaN();
expect(value).toBeGreaterThan(3);
expect(value).toBeCloseTo(0.3, 5);
expect(str).toContain('sub');
expect(str).toMatch(/pattern/);
expect(arr).toContain(item);
expect(fn).toThrow();
expect(fn).toThrowError('message');

// Negation
expect(value).not.toBe(other);
```

### Spies

```javascript
describe('UserService', () => {
  let service, api;

  beforeEach(() => {
    api = jasmine.createSpyObj('api', ['get', 'post']);
    service = new UserService(api);
  });

  it('fetches user from API', async () => {
    api.get.and.returnValue(Promise.resolve({ name: 'Alice' }));
    const user = await service.getUser(1);
    expect(user.name).toBe('Alice');
    expect(api.get).toHaveBeenCalledWith('/users/1');
    expect(api.get).toHaveBeenCalledTimes(1);
  });
});

// Spy on existing method
spyOn(obj, 'method').and.returnValue(42);
spyOn(obj, 'method').and.callThrough();    // Call original
spyOn(obj, 'method').and.throwError('err');
```

### Async Testing

```javascript
it('fetches data', async () => {
  const data = await fetchData();
  expect(data).toBeDefined();
});

// With done callback
it('fetches data', (done) => {
  fetchData().then(data => {
    expect(data).toBeDefined();
    done();
  });
});

// Clock control
beforeEach(() => { jasmine.clock().install(); });
afterEach(() => { jasmine.clock().uninstall(); });

it('handles timeout', () => {
  const callback = jasmine.createSpy();
  setTimeout(callback, 1000);
  jasmine.clock().tick(1001);
  expect(callback).toHaveBeenCalled();
});
```

## Setup: `npm install jasmine --save-dev && npx jasmine init`
## Run: `npx jasmine` or `npx jasmine spec/calculatorSpec.js`

## Deep Patterns

See `reference/playbook.md` for production-grade patterns:

| Section | What You Get |
|---------|-------------|
| §1 Project Setup | jasmine.json, TypeScript, spec reporter config |
| §2 Spies — Complete API | spyOn, createSpyObj, callFake, returnValues, call tracking |
| §3 Async Testing | async/await, expectAsync, promise matchers |
| §4 Custom Matchers | Domain-specific matchers, asymmetric matchers |
| §5 Test Organization | Nested describe, shared state, focused/excluded |
| §6 Fetch & Module Mocking | globalThis.fetch spy, HTTP error handling |
| §7 Browser Testing | DOM creation, keyboard events, focus trapping with Karma |
| §8 CI/CD Integration | GitHub Actions with coverage, browser testing |
| §9 Debugging Table | 12 common problems with causes and fixes |
| §10 Best Practices | 14-item checklist for production Jasmine testing |


[View on SkillFed](https://skillfed.io/LambdaTest/agent-skills/jasmine-skill) · [View on GitHub](https://github.com/LambdaTest/agent-skills)