Jest Skill

Generates Jest unit and integration tests in JavaScript or TypeScript. Covers mocking, snapshots, async testing, and React component testing. Use when user mentions "Jest", "describe/it/expect", "jest.mock", "toMatchSnapshot". Triggers on: "Jest", "expect().toBe()", "jest.mock", "snapshot test", "JS test", "React test".

386 stars 76 forksTesting & QAOfficial

Install

skills CLI (Claude Code, Cursor, Codex and more)

npx skills add LambdaTest/agent-skills --skill jest-skill

Manual install

git clone --depth 1 https://github.com/LambdaTest/agent-skills.git /tmp/agent-skills
mkdir -p ~/.claude/skills
cp -r /tmp/agent-skills/jest-skill ~/.claude/skills/jest-skill

Personal skills live in ~/.claude/skills. Use .claude/skills in a project folder to share a skill with your team.

From the SKILL.md

# Jest Testing Skill

## Core Patterns

### Basic Test

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

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

  test('throws on division by zero', () => {
    expect(() => calc.divide(10, 0)).toThrow('Division by zero');
  });
});
```

### Matchers

```javascript
expect(value).toBe(exact);                 // === strict
expect(value).toEqual(object);             // deep equality
expect(value).toBeTruthy();
expect(value).toBeNull();
expect(value).toBeGreaterThan(3);
expect(value).toBeCloseTo(0.3, 5);
expect(str).toMatch(/regex/);
expect(arr).toContain(item);
expect(arr).toHaveLength(3);
expect(obj).toHaveProperty('name');
expect(obj).toMatchObject({ name: 'Alice' });
expect(() => fn()).toThrow(CustomError);
```

### Mocking

Read the full skill on GitHub

Details

Skill name: jest-skill
Repository: LambdaTest/agent-skills
Path: jest-skill/SKILL.md
License: MIT
Repo updated: 30 October 2026
Listed in: VoltAgent/awesome-agent-skills

FAQ

What does the Jest Skill skill do?

How do I install the Jest Skill skill?

skills CLI (Claude Code, Cursor, Codex and more): npx skills add LambdaTest/agent-skills --skill jest-skill. Skills go in ~/.claude/skills (personal) or .claude/skills (project), and Claude loads them automatically when a task matches the description.

Is Jest Skill popular?

It lives in LambdaTest/agent-skills, which has 386 GitHub stars and 76 forks, and is included in 1 curated skill list.

Related skills

Appium Skill

386

LambdaTest/agent-skills

Generates production-grade Appium mobile automation scripts for Android and iOS in Java, Python, or JavaScript. Supports real device and emulator testing locally and on TestMu AI cloud with 100+ real devices. Use when the user asks to automate mobile apps, test on Android/iOS, write Appium tests, or mentions "Appium", "mobile testing", "real device", "app automation". Triggers on: "Appium", "mobile test", "Android test", "iOS test", "real device", "app automation", "UiAutomator", "XCUITest driver", "TestMu", "LambdaTest".

Testing & QAIn 1 list76

Behat Skill

386

LambdaTest/agent-skills

Generates Behat BDD tests for PHP with Gherkin feature files and MinkContext for browser testing. Use when user mentions "Behat", "PHP BDD", "Mink", "behat.yml". Triggers on: "Behat", "PHP BDD", "Mink", "behat.yml", "FeatureContext PHP".

Software DevelopmentIn 1 list76

Behave Skill

386

LambdaTest/agent-skills

Generates Behave BDD tests for Python with Gherkin feature files and step implementations. Use when user mentions "Behave", "Python BDD", "Python Gherkin". Triggers on: "Behave", "Python BDD", "behave test", "Python feature file".

Software DevelopmentIn 1 list76

Junit 5 Skill

386

LambdaTest/agent-skills

Generates production-grade JUnit 5 unit and integration tests in Java. Covers assertions, parameterized tests, lifecycle hooks, mocking with Mockito, and nested tests. Use when user mentions "JUnit", "JUnit 5", "@Test", "assertEquals", "Assertions", "Java unit test". Triggers on: "JUnit", "@Test", "assertEquals", "Java test", "unit test Java".

Testing & QAIn 1 list76

Jasmine Skill

386

LambdaTest/agent-skills

Generates Jasmine tests in JavaScript. BDD-style framework with spies and async support. Use when user mentions "Jasmine", "jasmine.createSpy", "toHaveBeenCalled". Triggers on: "Jasmine", "jasmine test", "createSpy", "Jasmine spec".

Testing & QAIn 1 list76

Kanecli Skill

386

LambdaTest/agent-skills

Browser automation + AI test authoring via kane-cli - run browser objectives, generate & refine test scenarios/cases from a description, design requirement-linked test suites from a PRD/spec (assurance), parse NDJSON output, inspect logs, save runnable _test.md. Use for any task requiring a real browser (navigate, click, fill forms, test web UI, take screenshots), or to author test cases, quick cases from a description via kane-cli generate; a designed, coverage-accounted suite from requirement documents via the assurance commands. Never write test cases by hand. Also runs mobile app tests - n

Testing & QAIn 1 list76

Browse the most popular Claude skills, all testing & qa skills, or write your own with the skills generator.