import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
import { NotificationManager } from '../../src/utils/NotificationManager.js';
import { SUBSCRIPTION_EVENTS } from '../../src/constants.js';
describe('NotificationManager Memory Management', () => {
let notificationManager: NotificationManager;
beforeEach(() => {
// Reset notification manager to ensure clean state
NotificationManager.reset();
notificationManager = NotificationManager.getInstance();
});
afterEach(() => {
NotificationManager.reset();
});
describe('Memory leak prevention', () => {
it('should provide unsubscribe functions to prevent memory leaks', () => {
const callback = vi.fn();
// Subscribe and get unsubscribe function
const unsubscribe = notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(1);
// Call unsubscribe function
unsubscribe();
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(0);
});
it('should accumulate listeners if unsubscribe is not called', () => {
const callback1 = vi.fn();
const callback2 = vi.fn();
const callback3 = vi.fn();
// Subscribe multiple times without unsubscribing
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback1);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback2);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback3);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(3);
// This shows the potential memory leak
notificationManager.notify(SUBSCRIPTION_EVENTS.FILE_UPDATED, { path: 'test.md' });
expect(callback1).toHaveBeenCalled();
expect(callback2).toHaveBeenCalled();
expect(callback3).toHaveBeenCalled();
});
it('should allow bulk cleanup of all listeners', () => {
const callback1 = vi.fn();
const callback2 = vi.fn();
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback1);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_CREATED, callback2);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(1);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_CREATED)).toBe(1);
// Clear all subscribers
notificationManager.clearSubscribers();
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(0);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_CREATED)).toBe(0);
});
it('should allow cleanup of specific event listeners', () => {
const callback1 = vi.fn();
const callback2 = vi.fn();
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback1);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_CREATED, callback2);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(1);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_CREATED)).toBe(1);
// Clear only FILE_UPDATED subscribers
notificationManager.clearSubscribers(SUBSCRIPTION_EVENTS.FILE_UPDATED);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(0);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_CREATED)).toBe(1);
});
});
describe('Automatic cleanup features', () => {
it('should detect and handle weak references for automatic cleanup', () => {
// This test demonstrates what automatic cleanup would look like
const callback = vi.fn();
// Create a subscription
const unsubscribe = notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(1);
// Simulate the object that owns the callback being garbage collected
// In a real implementation, we would use WeakRef or similar
unsubscribe();
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(0);
});
it('should provide diagnostic information about listener health', () => {
const callback1 = vi.fn();
const callback2 = vi.fn();
const callback3 = vi.fn();
// Create various subscriptions
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback1);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_CREATED, callback2);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.CACHE_INVALIDATED, callback3);
// Get diagnostic information
const registeredEvents = notificationManager.getRegisteredEvents();
expect(registeredEvents).toContain(SUBSCRIPTION_EVENTS.FILE_UPDATED);
expect(registeredEvents).toContain(SUBSCRIPTION_EVENTS.FILE_CREATED);
expect(registeredEvents).toContain(SUBSCRIPTION_EVENTS.CACHE_INVALIDATED);
expect(registeredEvents.length).toBe(3);
// Test new diagnostics method
const diagnostics = notificationManager.getDiagnostics();
expect(diagnostics.totalListeners).toBe(3);
expect(diagnostics.maxListeners).toBeGreaterThan(0);
expect(diagnostics.eventBreakdown).toHaveProperty(SUBSCRIPTION_EVENTS.FILE_UPDATED, 1);
expect(diagnostics.eventBreakdown).toHaveProperty(SUBSCRIPTION_EVENTS.FILE_CREATED, 1);
expect(diagnostics.eventBreakdown).toHaveProperty(SUBSCRIPTION_EVENTS.CACHE_INVALIDATED, 1);
});
it('should warn when approaching max listeners limit', () => {
// Create many subscriptions to approach limit
const callbacks = [];
const maxListeners = notificationManager.getMaxListeners();
// Create subscriptions up to 85% of max to trigger warning
const targetListeners = Math.floor(maxListeners * 0.85);
for (let i = 0; i < targetListeners; i++) {
const callback = vi.fn();
callbacks.push(callback);
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback);
}
const diagnostics = notificationManager.getDiagnostics();
expect(diagnostics.totalListeners).toBe(targetListeners);
expect(diagnostics.warning).toContain('Approaching max listeners limit');
});
});
describe('Process cleanup on exit', () => {
it('should clean up listeners when process exits', () => {
// This test shows how to implement process exit cleanup
const callback = vi.fn();
notificationManager.subscribe(SUBSCRIPTION_EVENTS.FILE_UPDATED, callback);
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(1);
// Simulate process exit cleanup
const cleanup = () => {
notificationManager.clearSubscribers();
};
// In real implementation, this would be:
// process.on('exit', cleanup);
// process.on('SIGINT', cleanup);
// process.on('SIGTERM', cleanup);
cleanup();
expect(notificationManager.getSubscriberCount(SUBSCRIPTION_EVENTS.FILE_UPDATED)).toBe(0);
});
});
});
