Merge #951

951: ufunc calls with mixed args and upcast types r=hgrecco a=keewis

This fixes an issue with calling ufuncs with mixed args including upcast types: Calling a bivariate ufunc like `np.maximum(da, 0 * ureg.m)` resulted in `pint` trying to work with upcast types because `__array_ufunc__` works with type objects while `is_upcast_type` checked object instances.

- [x] Executed ``black -t py36 . && isort -rc . && flake8`` with no errors
- [ ] The change is fully covered by automated unit tests


Co-authored-by: Keewis <keewis@posteo.de>

Author: bors[bot]

pint/compat.py

@@ -147,8 +147,12 @@ def _to_magnitude(value, force_ndarray=False):
 
 
 def is_upcast_type(other):
+    """ check if the type object is a upcast type
+
+    :param other: type
+    """
     # Check if class name is in preset list
-    return other.__class__.__name__ in ("PintArray", "Series", "DataArray")
+    return other.__name__ in ("PintArray", "Series", "DataArray")
 
 
 def eq(first, second, check_all):

pint/quantity.py

@@ -95,7 +95,7 @@ def wrapped(self, *args, **kwargs):
 def check_implemented(f):
     def wrapped(self, *args, **kwargs):
         other = args[0]
-        if is_upcast_type(other):
+        if is_upcast_type(type(other)):
             return NotImplemented
         # pandas often gets to arrays of quantities [ Q_(1,"m"), Q_(2,"m")]
         # and expects Quantity * array[Quantity] should return NotImplemented

pint/testsuite/test_babel.py

@@ -41,7 +41,7 @@ def test_registry_locale(self):
         self.assertEqual(time.format_babel(locale="ro", length="short"), "8.0 s")
         acceleration = distance / time ** 2
         self.assertEqual(
-            acceleration.format_babel(length="long"), "0.375 mètre par seconde²",
+            acceleration.format_babel(length="long"), "0.375 mètre par seconde²"
         )
         mks = ureg.get_system("mks")
         self.assertEqual(mks.format_babel(locale="fr_FR"), "métrique")