Allow all integer dtypes in polyval (#7619)

* Fixed unneeded ValueError

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Fixed unneeded ValueError

* Revert "Merge"

This reverts commit 87a82a2, reversing
changes made to fb27a96.

* add to whats-new

* add tests

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: dcherian <[email protected]>
Co-authored-by: Tom Nicholas <[email protected]>
Co-authored-by: Michael Niklas <[email protected]>

Author: 5 people

doc/whats-new.rst

@@ -35,6 +35,8 @@ Deprecations
 Bug fixes
 ~~~~~~~~~
 
+- Fix :py:meth:`xr.polyval` with non-system standard integer coeffs (:pull:`7619`).
+  By `Shreyal Gupta <https://github.com/Ravenin7>`_ and `Michael Niklas <https://github.com/headtr1ck>`_.
 
 Documentation
 ~~~~~~~~~~~~~

xarray/core/computation.py

@@ -1968,7 +1968,7 @@ def polyval(
         raise ValueError(
             f"Dimension `{degree_dim}` should be a coordinate variable with labels."
         )
-    if not np.issubdtype(coeffs[degree_dim].dtype, int):
+    if not np.issubdtype(coeffs[degree_dim].dtype, np.integer):
         raise ValueError(
             f"Dimension `{degree_dim}` should be of integer dtype. Received {coeffs[degree_dim].dtype} instead."
         )

xarray/tests/test_computation.py

@@ -2092,6 +2092,36 @@ def test_where_attrs() -> None:
             xr.DataArray([1000.0, 2000.0, 3000.0], dims="x"),
             id="timedelta",
         ),
+        pytest.param(
+            xr.DataArray([1, 2, 3], dims="x"),
+            xr.DataArray(
+                [2, 3, 4],
+                dims="degree",
+                coords={"degree": np.array([0, 1, 2], dtype=np.int64)},
+            ),
+            xr.DataArray([9, 2 + 6 + 16, 2 + 9 + 36], dims="x"),
+            id="int64-degree",
+        ),
+        pytest.param(
+            xr.DataArray([1, 2, 3], dims="x"),
+            xr.DataArray(
+                [2, 3, 4],
+                dims="degree",
+                coords={"degree": np.array([0, 1, 2], dtype=np.int32)},
+            ),
+            xr.DataArray([9, 2 + 6 + 16, 2 + 9 + 36], dims="x"),
+            id="int32-degree",
+        ),
+        pytest.param(
+            xr.DataArray([1, 2, 3], dims="x"),
+            xr.DataArray(
+                [2, 3, 4],
+                dims="degree",
+                coords={"degree": np.array([0, 1, 2], dtype=np.uint8)},
+            ),
+            xr.DataArray([9, 2 + 6 + 16, 2 + 9 + 36], dims="x"),
+            id="uint8-degree",
+        ),
     ],
 )
 def test_polyval(