Class DuckArrayModule

xarray/namedarray/pycompat.py:21–66

Solely for internal isinstance and version checks. Motivated by having to only import pint when required (as pint currently imports xarray) https://github.com/pydata/xarray/pull/5561#discussion_r664815718

class DuckArrayModule:
    """
    Solely for internal isinstance and version checks.

    Motivated by having to only import pint when required (as pint currently imports xarray)
    https://github.com/pydata/xarray/pull/5561#discussion_r664815718
    """

    module: ModuleType | None
    version: Version
    type: DuckArrayTypes
    available: bool

    def __init__(self, mod: ModType) -> None:
        duck_array_module: ModuleType | None
        duck_array_version: Version
        duck_array_type: DuckArrayTypes
        try:
            duck_array_module = import_module(mod)
            duck_array_version = Version(duck_array_module.__version__)

            if mod == "dask":
                duck_array_type = (import_module("dask.array").Array,)
            elif mod == "pint":
                duck_array_type = (duck_array_module.Quantity,)
            elif mod == "cupy":
                duck_array_type = (duck_array_module.ndarray,)
            elif mod == "sparse":
                duck_array_type = (duck_array_module.SparseArray,)
            elif mod == "cubed":
                duck_array_type = (duck_array_module.Array,)
            # Not a duck array module, but using this system regardless, to get lazy imports
            elif mod == "numbagg":
                duck_array_type = ()
            else:
                raise NotImplementedError

        except (ImportError, AttributeError):  # pragma: no cover
            duck_array_module = None
            duck_array_version = Version("0.0.0")
            duck_array_type = ()

        self.module = duck_array_module
        self.version = duck_array_version
        self.type = duck_array_type
        self.available = duck_array_module is not None


_cached_duck_array_modules: dict[ModType, DuckArrayModule] = {}