feat(site-builder): capture recent console errors for issue reports

Ring buffer of the most recent console.error/window-error messages (20 max, 500 chars each, message text only) for Task 19's report payload. installConsoleErrorBuffer() is idempotent via a marker stamped on the patched console.error itself (not just a module-scoped flag), so React 18 StrictMode double-invocation or HMR re-running this module's top level can't wrap an already-patched console.error and build a growing chain. The patch always chains to the original. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-09 10:37:32 -07:00
parent aba0d187d7
commit 9be71e8fd1
3 changed files with 181 additions and 0 deletions
@@ -0,0 +1,70 @@
+import { describe, test, expect, vi, afterEach } from 'vitest';
+import {
+  installConsoleErrorBuffer,
+  getRecentConsoleErrors,
+  __resetConsoleErrorBuffer,
+} from './console-buffer';
+
+afterEach(() => {
+  __resetConsoleErrorBuffer();
+  vi.restoreAllMocks();
+});
+
+describe('console error buffer', () => {
+  test('captures console.error calls', () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+    installConsoleErrorBuffer();
+    console.error('boom', 42);
+    const entries = getRecentConsoleErrors();
+    expect(entries).toHaveLength(1);
+    expect(entries[0].message).toBe('boom 42');
+    expect(typeof entries[0].ts).toBe('number');
+  });
+
+  test('always chains to the original console.error', () => {
+    const original = vi.spyOn(console, 'error').mockImplementation(() => {});
+    installConsoleErrorBuffer();
+    console.error('passed through');
+    expect(original).toHaveBeenCalledWith('passed through');
+  });
+
+  test('retains only the last 20 entries, oldest first', () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+    installConsoleErrorBuffer();
+    for (let i = 0; i < 25; i++) console.error(`e${i}`);
+    const entries = getRecentConsoleErrors();
+    expect(entries).toHaveLength(20);
+    expect(entries[0].message).toBe('e5');
+    expect(entries[19].message).toBe('e24');
+  });
+
+  test('truncates a long message to 500 characters', () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+    installConsoleErrorBuffer();
+    console.error('x'.repeat(900));
+    expect(getRecentConsoleErrors()[0].message).toHaveLength(500);
+  });
+
+  test('installing twice does not double-capture', () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+    installConsoleErrorBuffer();
+    installConsoleErrorBuffer();
+    console.error('once');
+    expect(getRecentConsoleErrors()).toHaveLength(1);
+  });
+
+  test('captures window error events', () => {
+    installConsoleErrorBuffer();
+    window.dispatchEvent(new ErrorEvent('error', { message: 'window blew up' }));
+    expect(getRecentConsoleErrors().some((e) => e.message.includes('window blew up'))).toBe(true);
+  });
+
+  test('getRecentConsoleErrors returns a copy, not the live array', () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+    installConsoleErrorBuffer();
+    console.error('a');
+    const first = getRecentConsoleErrors();
+    first.push({ ts: 0, message: 'injected' });
+    expect(getRecentConsoleErrors()).toHaveLength(1);
+  });
+});