Pytest Collection Policy¶

The gridworld marimo smoke notebooks include several files named test_mo.py under different environment directories. Plain pytest import mode imports those files as the same top-level module name, which causes import-mismatch collection errors after the first one is loaded.

pyproject.toml keeps --import-mode=importlib so explicitly collected notebook modules are imported by path-aware importlib machinery instead of colliding on their basename. The normal repository suite now sets testpaths = ["tests"]; marimo notebooks remain application artifacts rather than pytest modules. Explicit notebook configuration and CLI coverage is assigned to the experiments component instead of being discovered accidentally from notebook filenames.