The resources/generic-sensor-helpers.js tests require an implementation of the GenericSensorTest interface, which should emulate platform sensor backends. The GenericSensorTest interface is defined as:

 class MockSensor { // Sets fake data that is used to deliver sensor reading updates. async setSensorReading(FrozenArray<double> readingData); setStartShouldFail(boolean shouldFail); // Sets flag that forces sensor to fail. getSamplingFrequency(); // Return the sampling frequency. }; class MockSensorProvider { // Sets flag that forces mock SensorProvider to fail when getSensor() is // invoked. setGetSensorShouldFail(DOMString sensorType, boolean shouldFail); // Sets flag that forces mock SensorProvider to permissions denied when // getSensor() is invoked. setPermissionsDenied(DOMString sensorType, boolean permissionsDenied); getCreatedSensor(DOMString sensorType); // Return `MockSensor` interface. setMaximumSupportedFrequency(double frequency); // Sets the maximum frequency. setMinimumSupportedFrequency(double frequency); // Sets the minimum frequency. } class GenericSensorTest { initialize(); // Sets up the testing environment. async reset(); // Frees the resources. getSensorProvider(); // Returns `MockSensorProvider` interface. }; 

The Chromium implementation of the GenericSensorTest interface is located in generic_sensor_mocks.js.

Other browser vendors should provide their own implementations of the GenericSensorTest interface.

Known issue: a WebDriver extension is a better approach for the Generic Sensor tests automation.