testing-patterns

name	testing-patterns
description	Testing conventions and patterns for the Leather monorepo. Use when writing tests, creating test fixtures, or following TDD workflow. Covers Vitest setup, naming conventions, and common patterns.

Leather Testing Patterns

The monorepo uses Vitest for testing. Tests are co-located with source files.

File Naming

• Test files: {module-name}.spec.ts or {module-name}.spec.tsx
• Co-located with source: src/utils/format.ts → src/utils/format.spec.ts

Test Structure

import { functionUnderTest } from './module-name';

describe(functionUnderTest.name, () => {
  test('describes expected behavior', () => {
    // Arrange
    const input = createTestData();
    
    // Act
    const result = functionUnderTest(input);
    
    // Assert
    expect(result).toEqual(expected);
  });

  test('handles error case', () => {
    expect( (invalidInput)).();
  });
});