89dfde9535
Add a very lax mypy configuration, add it to tox -e linting, and fix/ignore the few errors that come up. The idea is to get it running before diving in too much. This enables: - Progressively adding type annotations and enabling more strict options, which will improve the codebase (IMO). - Annotating the public API in-line, and eventually exposing it to library users who use type checkers (with a py.typed file). Though, none of this is done yet. Refs https://github.com/pytest-dev/pytest/issues/3342.
Example test scripts ===================== The files in this folder are not direct tests, but rather example test suites that demonstrate certain issues/behaviours. In the future we will move part of the content of the acceptance tests here in order to have directly testable code instead of writing out things and then running them in nested pytest sessions/subprocesses. This will aid debugging and comprehension.