Catch Exception in combine

doc/source/whatsnew/v0.24.0.txt

@@ -505,6 +505,7 @@ ExtensionType Changes
 - :meth:`Series.astype` and :meth:`DataFrame.astype` now dispatch to :meth:`ExtensionArray.astype` (:issue:`21185:`).
 - Slicing a single row of a ``DataFrame`` with multiple ExtensionArrays of the same type now preserves the dtype, rather than coercing to object (:issue:`22784`)
 - Added :meth:`pandas.api.types.register_extension_dtype` to register an extension type with pandas (:issue:`22664`)
+- Renamed test prototype module names to avoid conflict with modules from the standard library (:issue:`22936`)
 
 .. _whatsnew_0240.api.incompatibilities:
 

pandas/core/series.py

@@ -2324,9 +2324,11 @@ def combine(self, other, func, fill_value=None):
         elif is_extension_array_dtype(self.values):
             # The function can return something of any type, so check
             # if the type is compatible with the calling EA
+            # ExtensionArray._from_sequence can raise anything, so we
+            # have to catch everything.
             try:
                 new_values = self._values._from_sequence(new_values)
-            except TypeError:
+            except Exception:
                 pass
 
         return self._constructor(new_values, index=new_index, name=new_name)

pandas/tests/extension/decimal_array/__init__.py

@@ -0,0 +1,4 @@
+from .array import DecimalArray, DecimalDtype
+
+
+__all__ = ['DecimalArray', 'DecimalDtype']

pandas/tests/extension/json_array/__init__.py

@@ -0,0 +1,3 @@
+from .array import JSONArray, JSONDtype
+
+__all__ = ['JSONArray', 'JSONDtype']

pandas/tests/extension/test_ops.py

@@ -0,0 +1,20 @@
+import operator
+from decimal import Decimal
+
+import pandas as pd
+import pandas.util.testing as tm
+from pandas.tests.extension.decimal_array import DecimalArray
+
+
+def test_combine_from_sequence_raises():
+    # https://github.com/pandas-dev/pandas/issues/22850
+    class BadDecimalArray(DecimalArray):
+        def _from_sequence(cls, scalars, dtype=None, copy=False):
+            raise KeyError("For the test")
+
+    ser = pd.Series(BadDecimalArray([Decimal("1.0"), Decimal("2.0")]))
+    result = ser.combine(ser, operator.add)
+
+    # note: object dtype
+    expected = pd.Series([Decimal("2.0"), Decimal("4.0")], dtype="object")
+    tm.assert_series_equal(result, expected)