Measurement tests receive a Benchmarker.

You use the Time() function to time how long the passed in body function takes to run You use the RecordValue() function to track arbitrary numerical measurements. The RecordValueWithPrecision() function can be used alternatively to provide the unit and resolution of the numeric measurement. The optional info argument is passed to the test reporter and can be used to provide the measurement data to a custom reporter with context.

See for more details