BUG: Fixed IntegerArray.__array_ufunc__ with nout (#36913)

We forgot to return.

Author: TomAugspurger

doc/source/whatsnew/v1.2.0.rst

@@ -436,7 +436,7 @@ ExtensionArray
 
 - Fixed Bug where :class:`DataFrame` column set to scalar extension type via a dict instantion was considered an object type rather than the extension type (:issue:`35965`)
 - Fixed bug where ``astype()`` with equal dtype and ``copy=False`` would return a new object (:issue:`284881`)
--
+- Fixed bug when applying a NumPy ufunc with multiple outputs to a :class:`pandas.arrays.IntegerArray` returning None (:issue:`36913`)
 
 
 Other

pandas/core/arrays/integer.py

@@ -412,7 +412,7 @@ def reconstruct(x):
 
         result = getattr(ufunc, method)(*inputs2, **kwargs)
         if isinstance(result, tuple):
-            tuple(reconstruct(x) for x in result)
+            return tuple(reconstruct(x) for x in result)
         else:
             return reconstruct(result)
 

pandas/tests/arrays/integer/test_function.py

@@ -64,6 +64,20 @@ def test_ufuncs_binary_int(ufunc):
     tm.assert_extension_array_equal(result, expected)
 
 
+def test_ufunc_binary_output():
+    a = integer_array([1, 2, np.nan])
+    result = np.modf(a)
+    expected = np.modf(a.to_numpy(na_value=np.nan, dtype="float"))
+
+    assert isinstance(result, tuple)
+    assert len(result) == 2
+
+    for x, y in zip(result, expected):
+        # TODO(FloatArray): This will return an extension array.
+        # y = integer_array(y)
+        tm.assert_numpy_array_equal(x, y)
+
+
 @pytest.mark.parametrize("values", [[0, 1], [0, None]])
 def test_ufunc_reduce_raises(values):
     a = integer_array(values)