reduction tests

Author: keewis

xarray_array_testing/reduction.py

@@ -0,0 +1,43 @@
+from contextlib import nullcontext
+from types import ModuleType
+
+import hypothesis.strategies as st
+import numpy as np
+import xarray.testing.strategies as xrst
+from hypothesis import given
+
+
+class ReductionTests:
+    xp: ModuleType
+
+    @staticmethod
+    def array_strategy_fn(*, shape, dtype):
+        raise NotImplementedError
+
+    @staticmethod
+    def assert_equal(a, b):
+        np.testing.assert_allclose(a, b)
+
+    @staticmethod
+    def expected_errors(op, **parameters):
+        return nullcontext()
+
+    @given(st.data())
+    def test_variable_mean(self, data):
+        variable = data.draw(xrst.variables(array_strategy_fn=self.array_strategy_fn))
+
+        with self.expected_errors("mean", variable=variable):
+            actual = variable.mean().data
+            expected = self.xp.mean(variable.data)
+
+        self.assert_equal(actual, expected)
+
+    @given(st.data())
+    def test_variable_prod(self, data):
+        variable = data.draw(xrst.variables(array_strategy_fn=self.array_strategy_fn))
+
+        with self.expected_errors("prod", variable=variable):
+            actual = variable.prod().data
+            expected = self.xp.prod(variable.data)
+
+        self.assert_equal(actual, expected)

xarray_array_testing/tests/test_numpy.py

@@ -2,6 +2,7 @@
 import numpy as np
 
 from xarray_array_testing.creation import CreationTests
+from xarray_array_testing.reduction import ReductionTests
 
 
 def create_numpy_array(*, shape, dtype):
@@ -15,3 +16,11 @@ class TestCreationNumpy(CreationTests):
     @staticmethod
     def array_strategy_fn(*, shape, dtype):
         return create_numpy_array(shape=shape, dtype=dtype)
+
+
+class TestReductionNumpy(ReductionTests):
+    xp = np
+
+    @staticmethod
+    def array_strategy_fn(*, shape, dtype):
+        return create_numpy_array(shape=shape, dtype=dtype)