BUG: Use self._constructor_sliced in df._reduce to respect subclassed…

pandas/core/frame.py

@@ -7878,7 +7878,7 @@ def _get_data(axis_matters):
                     result = coerce_to_dtypes(result, self.dtypes)
 
         if constructor is not None:
-            result = Series(result, index=labels)
+            result = self._constructor_sliced(result, index=labels)
         return result
 
     def nunique(self, axis=0, dropna=True):

pandas/tests/frame/test_subclass.py

@@ -557,3 +557,25 @@ def strech(row):
         result = df.apply(lambda x: [1, 2, 3], axis=1)
         assert not isinstance(result, tm.SubclassedDataFrame)
         tm.assert_series_equal(result, expected)
+
+    def test_subclassed_numeric_reductions(self, all_numeric_reductions):
+        # GH 25596
+
+        op = all_numeric_reductions
+
+        df = tm.SubclassedDataFrame({"A": [1, 2, 3], "B": [4, 5, 6], "C": [7, 8, 9]})
+
+        result = getattr(df, op)()
+
+        assert isinstance(result, tm.SubclassedSeries)
+
+    def test_subclassed_boolean_reductions(self, all_boolean_reductions):
+        # GH 25596
+
+        op = all_boolean_reductions
+
+        df = tm.SubclassedDataFrame({"A": [1, 2, 3], "B": [4, 5, 6], "C": [7, 8, 9]})
+
+        result = getattr(df, op)()
+
+        assert isinstance(result, tm.SubclassedSeries)