Enable mypy checking for test_utils and test_parallelcompat (#10691)

* Enable mypy checking for test_utils and test_parallelcompat

Removes xarray.tests.test_utils and xarray.tests.test_parallelcompat from the mypy
exclusion list by fixing type issues in these files:

- Added type annotations where needed
- Added targeted type: ignore comments for intentional test behaviors
- Fixed function call signatures to match expected types

All tests continue to pass and mypy now checks these files with check_untyped_defs=true.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

* Also enable mypy for test_missing

Removes xarray.tests.test_missing from the mypy exclusion list by
fixing type issues:

- Added type: ignore comments for intentional test cases with invalid methods
- Added type annotation for kwargs dict

All 115 tests continue to pass.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: max-sixty

pyproject.toml

@@ -198,12 +198,9 @@ module = [
   "xarray.tests.test_duck_array_ops",
   "xarray.tests.test_indexing",
   "xarray.tests.test_merge",
-  "xarray.tests.test_missing",
-  "xarray.tests.test_parallelcompat",
   "xarray.tests.test_sparse",
   "xarray.tests.test_ufuncs",
   "xarray.tests.test_units",
-  "xarray.tests.test_utils",
   "xarray.tests.test_variable",
   "xarray.tests.test_weighted",
 ]

xarray/tests/test_missing.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import itertools
+from typing import Any
 from unittest import mock
 
 import numpy as np
@@ -204,7 +205,7 @@ def test_interpolate_unsorted_index_raises():
     vals = np.array([1, 2, 3], dtype=np.float64)
     expected = xr.DataArray(vals, dims="x", coords={"x": [2, 1, 3]})
     with pytest.raises(ValueError, match=r"Index 'x' must be monotonically increasing"):
-        expected.interpolate_na(dim="x", method="index")
+        expected.interpolate_na(dim="x", method="index")  # type: ignore[arg-type]
 
 
 def test_interpolate_no_dim_raises():
@@ -216,14 +217,14 @@ def test_interpolate_no_dim_raises():
 def test_interpolate_invalid_interpolator_raises():
     da = xr.DataArray(np.array([1, 2, np.nan, 5], dtype=np.float64), dims="x")
     with pytest.raises(ValueError, match=r"not a valid"):
-        da.interpolate_na(dim="x", method="foo")
+        da.interpolate_na(dim="x", method="foo")  # type: ignore[arg-type]
 
 
 def test_interpolate_duplicate_values_raises():
     data = np.random.randn(2, 3)
     da = xr.DataArray(data, coords=[("x", ["a", "a"]), ("y", [0, 1, 2])])
     with pytest.raises(ValueError, match=r"Index 'x' has duplicate values"):
-        da.interpolate_na(dim="x", method="foo")
+        da.interpolate_na(dim="x", method="foo")  # type: ignore[arg-type]
 
 
 def test_interpolate_multiindex_raises():
@@ -331,15 +332,15 @@ def test_interpolate_limits():
 @requires_scipy
 def test_interpolate_methods():
     for method in ["linear", "nearest", "zero", "slinear", "quadratic", "cubic"]:
-        kwargs = {}
+        kwargs: dict[str, Any] = {}
         da = xr.DataArray(
             np.array([0, 1, 2, np.nan, np.nan, np.nan, 6, 7, 8], dtype=np.float64),
             dims="x",
         )
-        actual = da.interpolate_na("x", method=method, **kwargs)
+        actual = da.interpolate_na("x", method=method, **kwargs)  # type: ignore[arg-type]
         assert actual.isnull().sum() == 0
 
-        actual = da.interpolate_na("x", method=method, limit=2, **kwargs)
+        actual = da.interpolate_na("x", method=method, limit=2, **kwargs)  # type: ignore[arg-type]
         assert actual.isnull().sum() == 1
 
 

xarray/tests/test_parallelcompat.py

@@ -48,7 +48,7 @@ def __new__(
     def __array_finalize__(self, obj):
         if obj is None:
             return
-        self.chunks = getattr(obj, "chunks", None)
+        self.chunks = getattr(obj, "chunks", None)  # type: ignore[assignment]
 
     def rechunk(self, chunks, **kwargs):
         copied = self.copy()

xarray/tests/test_utils.py

@@ -23,7 +23,7 @@ def new_method():
             pass
 
         old_method = utils.alias(new_method, "old_method")
-        assert "deprecated" in old_method.__doc__
+        assert "deprecated" in old_method.__doc__  # type: ignore[operator]
         with pytest.warns(Warning, match="deprecated"):
             old_method()
 
@@ -102,10 +102,10 @@ def test_compat_dict_union(self):
             utils.compat_dict_union(self.x, self.z)
 
     def test_dict_equiv(self):
-        x = {}
+        x: dict = {}
         x["a"] = 3
         x["b"] = np.array([1, 2, 3])
-        y = {}
+        y: dict = {}
         y["b"] = np.array([1.0, 2.0, 3.0])
         y["a"] = 3
         assert utils.dict_equiv(x, y)  # two nparrays are equal
@@ -129,11 +129,11 @@ def test_dict_equiv(self):
     def test_frozen(self):
         x = utils.Frozen(self.x)
         with pytest.raises(TypeError):
-            x["foo"] = "bar"
+            x["foo"] = "bar"  # type: ignore[index]
         with pytest.raises(TypeError):
-            del x["a"]
+            del x["a"]  # type: ignore[attr-defined]
         with pytest.raises(AttributeError):
-            x.update(self.y)
+            x.update(self.y)  # type: ignore[attr-defined]
         assert x.mapping == self.x
         assert repr(x) in (
             "Frozen({'a': 'A', 'b': 'B'})",
@@ -231,11 +231,11 @@ def test_hidden_key_dict():
 
 
 def test_either_dict_or_kwargs():
-    result = either_dict_or_kwargs(dict(a=1), None, "foo")
+    result = either_dict_or_kwargs(dict(a=1), {}, "foo")
     expected = dict(a=1)
     assert result == expected
 
-    result = either_dict_or_kwargs(None, dict(a=1), "foo")
+    result = either_dict_or_kwargs({}, dict(a=1), "foo")
     expected = dict(a=1)
     assert result == expected