claude-mem/tests/happy-paths/context-injection.test.ts

/**
 * Happy Path Test: Context Injection (SessionStart)
 *
 * Tests that when a session starts, the context hook can retrieve
 * formatted context from the worker containing recent observations.
 */
import { describe, it, expect, beforeEach, vi } from 'vitest';
import { sampleObservation, featureObservation } from '../helpers/scenarios.js';
import { getWorkerPort } from '../../src/shared/worker-utils.js';

describe('Context Injection (SessionStart)', () => {
  const WORKER_PORT = getWorkerPort();
  const PROJECT_NAME = 'claude-mem';

  beforeEach(() => {
    vi.clearAllMocks();
  });

  it('returns formatted context when observations exist', async () => {
    // This is a component test that verifies the happy path:
    // Session starts → Hook calls worker → Worker queries database → Returns formatted context

    // Setup: Mock fetch to simulate worker response
    const mockContext = `# [claude-mem] recent context

## Recent Work (2 observations)

### [bugfix] Fixed parser bug
The XML parser was not handling empty tags correctly.
Files: /project/src/parser.ts

### [feature] Added search functionality
Implemented full-text search using FTS5.
Files: /project/src/services/search.ts`;

    global.fetch = vi.fn().mockResolvedValue({
      ok: true,
      status: 200,
      text: async () => mockContext
    });

    // Execute: Call context endpoint (what the hook does)
    const response = await fetch(
      `http://127.0.0.1:${WORKER_PORT}/api/context/inject?project=${encodeURIComponent(PROJECT_NAME)}`
    );

    // Verify: Response is successful
    expect(response.ok).toBe(true);
    expect(response.status).toBe(200);

    // Verify: Context contains observations
    const text = await response.text();
    expect(text).toContain('recent context');
    expect(text).toContain('Fixed parser bug');
    expect(text).toContain('Added search functionality');
    expect(text).toContain('bugfix');
    expect(text).toContain('feature');
  });

  it('returns fallback message when worker is down', async () => {
    // Setup: Mock fetch to simulate worker not available
    global.fetch = vi.fn().mockRejectedValue(new Error('ECONNREFUSED'));

    // Execute: Attempt to call context endpoint
    try {
      await fetch(
        `http://127.0.0.1:${WORKER_PORT}/api/context/inject?project=${encodeURIComponent(PROJECT_NAME)}`
      );
    } catch (error: any) {
      // Verify: Error indicates worker is down
      expect(error.message).toContain('ECONNREFUSED');
    }

    // The hook should handle this gracefully and return a fallback message
    // (This would be tested in hook-specific tests, not the worker endpoint tests)
  });

  it('handles empty observations gracefully', async () => {
    // Setup: Mock fetch to simulate no observations available
    const emptyContext = `# [claude-mem] recent context

No observations found for this project.`;

    global.fetch = vi.fn().mockResolvedValue({
      ok: true,
      status: 200,
      text: async () => emptyContext
    });

    // Execute: Call context endpoint
    const response = await fetch(
      `http://127.0.0.1:${WORKER_PORT}/api/context/inject?project=${encodeURIComponent(PROJECT_NAME)}`
    );

    // Verify: Returns success with empty message
    expect(response.ok).toBe(true);
    const text = await response.text();
    expect(text).toContain('No observations found');
  });

  it('supports colored output when requested', async () => {
    // Setup: Mock fetch to simulate colored response
    const coloredContext = `# [claude-mem] recent context

## Recent Work (1 observation)

### \x1b[33m[bugfix]\x1b[0m Fixed parser bug
The XML parser was not handling empty tags correctly.`;

    global.fetch = vi.fn().mockResolvedValue({
      ok: true,
      status: 200,
      text: async () => coloredContext
    });

    // Execute: Call context endpoint with colors parameter
    const response = await fetch(
      `http://127.0.0.1:${WORKER_PORT}/api/context/inject?project=${encodeURIComponent(PROJECT_NAME)}&colors=true`
    );

    // Verify: Response contains ANSI color codes
    expect(response.ok).toBe(true);
    const text = await response.text();
    expect(text).toContain('\x1b['); // ANSI escape code
  });
});