The shapedetection-helpers.js tests require implementations of the FaceDetectionTest and BarcodeDetectionTest interfaces, which should emulate platform shape detection backends.

The FaceDetectionTest interface is defined as:

 class FaceDetectionTest { async initialize(); // Sets up the testing environment. async reset(); // Frees the resources. MockFaceDetectionProvider(); //Returns `MockFaceDetectionProvider` interface. }; class MockFaceDetectionProvider { getFrameData(); //Gets frame data of detection result. getMaxDetectedFaces(); //Gets value of `maxDetectedFaces` in `FaceDetector` constructor getFastMode(); //Gets value of `fastMode` in `FaceDetector` constructor }; 

The Chromium implementation of the FaceDetectionTest interface is located in mock-facedetection.js.

The BarcodeDetectionTest interface is defined as:

 class BarcodeDetectionTest { async initialize(); // Sets up the testing environment. async reset(); // Frees the resources. MockBarcodeDetectionProvider(); //Returns `MockBarcodeDetectionProvider` interface. }; class MockBarcodeDetectionProvider { async enumerateSupportedFormats(); //Enumerates supported formats getFrameData(); //Gets frame data of detection result. getFormats(); //Gets value of `formats` in `BarcodeDetector` constructor }; 

The Chromium implementation of the BarcodeDetectionTest interface is located in mock-barcodedetection.js.

Other browser vendors should provide their own implementations of the FaceDetectionTest and BarcodeDetectionTest interfaces.