test(web): AutoUpdatingCameraImage

web/src/components/AutoUpdatingCameraImage.jsx

@@ -4,7 +4,7 @@ import { useCallback, useState } from 'preact/hooks';
 
 const MIN_LOAD_TIMEOUT_MS = 200;
 
-export default function AutoUpdatingCameraImage({ camera, searchParams, showFps = true }) {
+export default function AutoUpdatingCameraImage({ camera, searchParams = '', showFps = true }) {
   const [key, setKey] = useState(Date.now());
   const [fps, setFps] = useState(0);
 

web/src/components/__tests__/AutoUpdatingCameraImage.test.jsx

@@ -0,0 +1,42 @@
+import { h } from 'preact';
+import AutoUpdatingCameraImage from '../AutoUpdatingCameraImage';
+import { screen, render } from '@testing-library/preact';
+
+let mockOnload;
+jest.mock('../CameraImage', () => {
+  function CameraImage({ onload, searchParams }) {
+    mockOnload = () => {
+      onload();
+    };
+    return <div data-testid="camera-image">{searchParams}</div>;
+  }
+  return {
+    __esModule: true,
+    default: CameraImage,
+  };
+});
+
+describe('AutoUpdatingCameraImage', () => {
+  let dateNowSpy;
+  beforeEach(() => {
+    dateNowSpy = jest.spyOn(Date, 'now').mockReturnValue(0);
+  });
+
+  test('shows FPS by default', async () => {
+    render(<AutoUpdatingCameraImage camera="tacos" />);
+    expect(screen.queryByText('Displaying at 0fps')).toBeInTheDocument();
+  });
+
+  test('does not show FPS if turned off', async () => {
+    render(<AutoUpdatingCameraImage camera="tacos" showFps={false} />);
+    expect(screen.queryByText('Displaying at 0fps')).not.toBeInTheDocument();
+  });
+
+  test('on load, sets a new cache key to search params', async () => {
+    dateNowSpy.mockReturnValueOnce(100).mockReturnValueOnce(200).mockReturnValueOnce(300);
+    render(<AutoUpdatingCameraImage camera="tacos" searchParams="foo" />);
+    mockOnload();
+    jest.runAllTimers();
+    expect(screen.queryByText('cache=100&foo')).toBeInTheDocument();
+  });
+});