Testing

PebbleOS has two test suites, which check different things:

	Unit tests	Integration tests
What	Individual modules, against fakes and stubs	The whole firmware, as it ships
Where	On the host	On the emulator, the native simulator or a watch
Written in	C, with clar	Python, with pytest
Lives in	`tests/`	`tests/integration/`
Run with	pbl test	pbl itest

Unit tests are fast and precise: they build a few firmware sources for the host, so a module’s behaviour can be checked in isolation, including rendering against reference images. Integration tests drive the running firmware from the outside, pressing buttons, comparing screenshots, reading logs and measuring current, so they catch what only shows up once everything runs together.

CI runs the unit tests on every change to the sources, and the integration tests on the three emulator boards, for both the normal and the recovery firmware. A lab watch runs them on real hardware as well.