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

  class GenericSensorTest {
    async initialize();  // Sets up the testing enviroment.
    async reset(); // Frees the resources.

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.