angularjs-unit-test_skill

Overview

This skill helps you write, refactor, and maintain unit tests for AngularJS applications using Jasmine and Jest. It focuses on practical patterns for testing controllers, services, filters, directives, HTTP interactions, promises, and scope behavior. The goal is fast, reliable tests with clear organization and measurable coverage.

How this skill works

The skill provides concrete test structures, templates, and patterns (AAA, mocking/spying, fixtures, edge-case testing, snapshot testing for Jest). It explains how to mock HTTP with $httpBackend or jest.mock(), handle $q and $timeout, and inject dependencies for isolated units. It also covers test runner setup (Karma for Jasmine, Jest configuration) and CI integration for automated coverage reporting.

When to use it

• Adding unit tests to an existing AngularJS project
• Writing or refactoring controller, service, directive, or filter tests
• Mocking HTTP calls and async behavior in unit tests
• Choosing between Jasmine (native AngularJS fit) and Jest (modern features, snapshots)
• Integrating tests into CI/CD pipelines for coverage and regression checks

Best practices

• Follow the AAA pattern: Arrange, Act, Assert for every test
• Keep tests independent: use beforeEach/afterEach to reset state
• Use realistic mocks and spies; avoid over-simplified stubs
• Aim for broad coverage: happy paths, edge cases, and errors
• Keep tests fast: prefer in-memory mocks and avoid real network or DB calls
• Organize one test file per component and use meaningful test names

Example use cases

• Unit-testing a controller that initializes scope and triggers events
• Testing a service that performs $http calls with $httpBackend mocks
• Validating directive compilation and DOM manipulation in isolation
• Testing promise resolution and rejection using $q and $rootScope.$apply()
• Migrating a test suite to Jest to add snapshot testing and faster mocks