Instruments offers an open schema for fetching signpost data via Apple's `OSLog` type. The Timelane code packages use Apple's os
framework to report subscriptions' data to Instruments.
The Timelane Instrument is a custom Instrument that uses the predefined by Apple data models to receive the signpost data and the default Instruments UI to render the data on screen.
If you right click on a given unit test and select "Profile test...()" from the popup menu Xcode will build you test bundle and open up Instruments. However due to a likely bug in Instruments will not receive signpost data and Timelane will not plot data as usual.
If you do, however, afterwards profile the build app bundle that will still execute only the profiled test and this time Instruments will receive and plot signpost data.
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