"""Perf-tier tests.

A package (like every other ``tests/`` subdirectory) so that
``tests/perf/conftest.py`` is importable as ``tests.perf.conftest`` — the
comparator's own self-tests exercise :class:`Baselines` directly rather than
through the session fixture, and a self-test that imported a *second copy* of
the module would be pinning something other than what the pins run.
"""
