Function test_eval_dask_basic_arithmetic

xarray/tests/test_eval.py:416–432

Test that basic arithmetic with dask arrays returns dask-backed result.

()

@requires_dask
def test_eval_dask_basic_arithmetic() -> None:
    """Test that basic arithmetic with dask arrays returns dask-backed result."""
    from xarray.core.utils import is_duck_dask_array

    ds = Dataset(
        {"a": ("x", np.arange(10.0)), "b": ("x", np.linspace(0, 1, 10))}
    ).chunk({"x": 5})

    with raise_if_dask_computes():
        result = ds.eval("a + b")

    assert isinstance(result, DataArray)
    assert is_duck_dask_array(result.data)

    # Verify correctness when computed
    expected = ds["a"] + ds["b"]
    assert_equal(result, expected)


@requires_dask