Writing Tests

Write effective tests using Vitest and React Testing Library.

Quick Start

Create a unit test in src/common/__tests__/utils/math.test.ts:

import { describe, it, expect } from 'vitest';
import { add } from '../../utils/math';

describe('math utility', () => {
  it('adds two numbers correctly', () => {
    expect(add(1, 2)).toBe(3);
  });
});

Run tests with npm run test.

Core Patterns

Unit Testing

Focus on pure functions and logic in src/main or src/common. Use vi.mock() for dependencies.

references/unit-testing-examples.md

Component Testing

Test React components in src/renderer. Focus on user interactions and props.

references/component-testing-patterns.md

Mocking

Use centralized mock factories for consistent testing across components and contexts.

references/mocking-guide.md - Mock factories and API patterns

Debugging Failing Tests

Read the error output and identify the failing assertion
Check mock setup — verify vi.mock() paths and return values match expectations
For component tests, inspect rendered output with screen.debug()
Run a single test in isolation: npm run test:node -- --no-color -t "test name"
Verify coverage: npm run test:coverage to confirm new code is tested

Advanced Usage

For detailed information:

references/test-organization.md - Directory structure and naming
references/running-tests.md - CLI commands and coverage
references/best-practices.md - Principles and patterns
references/test-patterns.md - Code templates
assets/test-checklist.md - Pre-flight checklist

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