### Question:
MetricSensor implements Sensor { @Override public void describe(SensorDescriptor descriptor) { descriptor .name("CSS Metrics") .onlyOnLanguage(CssLanguage.KEY); } MetricSensor(FileLinesContextFactory fileLinesContextFactory); @Override void describe(SensorDescriptor descriptor); @Override void execute(SensorContext context);  }### Answer:
@Test public void should_describe() { DefaultSensorDescriptor desc = new DefaultSensorDescriptor(); new MetricSensor(null).describe(desc); assertThat(desc.languages()).containsOnly("css"); }