This library is an embedded-hal compliant driver for a GPIO-driven CD74HC4067 chip. It is completely hardware-agnostic, only requiring 5 output pins to operate. Given a compliant implementation of embedded-hal for a target, this driver should work there out-of-the-box.
To read more on this nice little driver, blog post here.
The tests for the library also show a basic example of how to use embedded-hal-mock to test drivers when the hardware isn't there yet :) or on CI. Note, the test coverage is practically 100% line coverage.
The only exception are the calls to PhantomData::<...>, as they are excluded from the compiled binary by design.