Class FixtureDef

src/_pytest/fixtures.py:1050–1245

A container for a fixture definition. Note: At this time, only explicitly documented fields and methods are considered public stable API.

class FixtureDef(Generic[FixtureValue]):
    """A container for a fixture definition.

    Note: At this time, only explicitly documented fields and methods are
    considered public stable API.
    """

    def __init__(
        self,
        config: Config,
        baseid: str | None | NotSetType,
        argname: str,
        func: _FixtureFunc[FixtureValue],
        scope: Scope | ScopeName | Callable[[str, Config], ScopeName] | None,
        params: Sequence[object] | None,
        ids: tuple[object | None, ...] | Callable[[Any], object | None] | None = None,
        *,
        node: nodes.Node | NotSetType = NOTSET,
        # only used in a deprecationwarning msg, can be removed in pytest9
        _autouse: bool = False,
        _ispytest: bool = False,
    ) -> None:
        check_ispytest(_ispytest)
        # Emit deprecation warning if deprecated baseid string is used.
        if node is NOTSET:
            warnings.warn(FIXTURE_BASEID_DEPRECATED, stacklevel=2)
        if baseid is NOTSET:
            baseid = None
        # The node where this fixture was defined, if available.
        # Used for node-based matching which is more robust than string matching.
        self.node: Final = node if node is not NOTSET else None
        # The "base" node ID for the fixture.
        #
        # This is a node ID prefix. A fixture is only available to a node (e.g.
        # a `Function` item) if the fixture's baseid is a nodeid of a parent of
        # node.
        #
        # For a fixture found in a Collector's object (e.g. a `Module`s module,
        # a `Class`'s class), the baseid is the Collector's nodeid.
        #
        # For a fixture found in a conftest plugin, the baseid is the conftest's
        # directory path relative to the rootdir.
        #
        # For other plugins, the baseid is the empty string (always matches).
        # When node is available, baseid is derived from node.nodeid.
        #
        # Deprecated: replaced by ``node``.
        self.baseid: Final = node.nodeid if node is not NOTSET else (baseid or "")
        # Whether the fixture was found from a node or a conftest in the
        # collection tree. Will be false for fixtures defined in non-conftest
        # plugins.
        #
        # Deprecated: kept only to back the deprecated ``has_location`` property.
        self._has_location: Final = node is not NOTSET or baseid is not None
        # The fixture factory function.
        self.func: Final = func
        # The name by which the fixture may be requested.
        self.argname: Final = argname