Testing Guide

Testing standards and practices for Synap Backend

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Testing Strategy

Unit Tests

• Test individual functions and classes
• Mock external dependencies
• Fast execution (< 100ms per test)

Integration Tests

• Test component interactions
• Use test database
• Test event flows

E2E Tests

• Test complete user flows
• Use real services (Docker)
• Validate end-to-end behavior

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Test Structure

import { describe, it, expect, beforeEach } from 'vitest';

describe('NoteService', () => {
  beforeEach(() => {
    // Setup test data
  });
  
  it('should create note', async () => {
    const result = await service.create({ content: 'Test' });
    expect(result.id).toBeDefined();
  });
  
  it('should validate input', async () => {
    await expect(
      service.create({ content: '' })
    ).rejects.toThrow(ValidationError);
  });
});

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Testing Event Handlers

import { NoteCreationHandler } from './note-creation-handler.js';

describe('NoteCreationHandler', () => {
  it('should process note.creation.requested event', async () => {
    const event = createSynapEvent({
      type: 'note.creation.requested',
      data: { content: 'Test' },
    });
    
    const handler = new NoteCreationHandler();
    const result = await handler.handle(event, mockStep);
    
    expect(result.success).toBe(true);
  });
});

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Testing Agents

import { runSynapAgent } from '@synap/ai';

describe('SynapAgent', () => {
  it('should classify intent', async () => {
    const result = await runSynapAgent({
      userId: 'user-123',
      message: 'Create a note',
    });
    
    expect(result.intent).toBe('command');
  });
});

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Best Practices

1. Test behavior, not implementation - Focus on outcomes
2. Use fixtures - Reusable test data
3. Mock external services - Don't call real APIs
4. Test error cases - Invalid inputs, failures
5. Keep tests fast - Use mocks and stubs

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Next: See Code Style for coding standards.