Disable unavailable subreddits after Reddit 404

tests/subreddit-polling-control.test.ts

@@ -0,0 +1,21 @@
+import { describe, expect, it, vi } from 'vitest';
+import { createConfigBackedSubredditPollingControl } from '../src/services/subreddit-polling-control.js';
+import { getTestConfig } from './testUtils.js';
+import { createMockLogger } from './mockLogger.js';
+
+describe('config-backed subreddit polling control', () => {
+  it('disables and persists only the matched subreddit', () => {
+    const config = getTestConfig({ reddit: { subreddits: [{ name: 'gone', type: 'image' }, { name: 'active', type: 'chat' }] } });
+    const store = { load: vi.fn(), save: vi.fn() };
+    const control = createConfigBackedSubredditPollingControl(config, store, createMockLogger());
+
+    control.disableUnavailableSubreddit('GONE');
+
+    expect(config.reddit.subreddits).toEqual([
+      expect.objectContaining({ name: 'gone', enabled: false }),
+      expect.objectContaining({ name: 'active' }),
+    ]);
+    expect(store.save).toHaveBeenCalledWith(config);
+    expect(control.isSubredditEnabled('gone')).toBe(false);
+  });
+});