The resolved single-package fallback target.
Attributes
----------
root
Absolute package root: the config file's directory (ADR-T-12
walk, ยง9 row 2) or cwd itself (``--package`` fallback, row 6).
package_id
Basename of *root*, unless the discovered ``pyproject.toml``
carries a ``[tool.oct.test].package_id`` override (clause 5),
or ``--package`` supplied the id (row 6).
config_file
The discovered config file; ``None`` in the ``--package``
fallback, which performs no walk.
Definition at line 102 of file discovery.py.