Method prune_dependency_tree

src/_pytest/fixtures.py:420–437

Recompute names_closure from initialnames and name2fixturedefs. Can only reduce names_closure, which means that the new closure will always be a subset of the old one. The order is preserved. This method is needed because direct parametrization may shadow some of th

(self)

    name2fixturedefs: dict[str, Sequence[FixtureDef[Any]]]

    def prune_dependency_tree(self) -> None:
        """Recompute names_closure from initialnames and name2fixturedefs.

        Can only reduce names_closure, which means that the new closure will
        always be a subset of the old one. The order is preserved.

        This method is needed because direct parametrization may shadow some
        of the fixtures that were included in the originally built dependency
        tree. In this way the dependency tree can get pruned, and the closure
        of argnames may get reduced.
        """
        closure = set(
            traverse_fixture_closure(
                self.initialnames,
                getfixturedefs=self.name2fixturedefs.get,
            )
        )
        self.names_closure[:] = (name for name in self.names_closure if name in closure)


class FixtureRequest(abc.ABC):