Prior to this commit, the tests for the linter partially depended on
project files. This coupling risks churn in the tests: if the needs of
the project change (e.g. a harness file is modified), then the linter
tests would need to be updated. It also made the tests more difficult to
understand because the input was both larger and more complicated than
necessary to exercise the relevant functionality.
Execute the tests in the context of the fixture directory and introduce
minimal support files that serve the same purpose as the corresponding
project files.
Mike Pennisi