BUG: _can_use_numexpr did not handle Series case correctly

Fixes: pandas-dev#27636

Author: Connor Charles

pandas/core/computation/expressions.py

@@ -80,7 +80,7 @@ def _can_use_numexpr(op, op_str, a, b, dtype_check):
             # check for dtype compatibility
             dtypes = set()
             for o in [a, b]:
-                if hasattr(o, "dtypes"):
+                if hasattr(o, "dtypes") and o.ndim > 1:
                     s = o.dtypes.value_counts()
                     if len(s) > 1:
                         return False

pandas/tests/test_expressions.py

@@ -1,3 +1,4 @@
+from itertools import product
 import operator
 import re
 
@@ -66,7 +67,7 @@ def run_arithmetic(self, df, other, assert_func, check_dtype=False, test_flex=Tr
                 operator_name = "truediv"
 
             if test_flex:
-                op = lambda x, y: getattr(df, arith)(y)
+                op = lambda x, y: getattr(x, arith)(y)
                 op.__name__ = arith
             else:
                 op = getattr(operator, operator_name)
@@ -431,3 +432,30 @@ def test_bool_ops_column_name_dtype(self, test_input, expected):
         # GH 22383 - .ne fails if columns containing column name 'dtype'
         result = test_input.loc[:, ["a", "dtype"]].ne(test_input.loc[:, ["a", "dtype"]])
         assert_frame_equal(result, expected)
+
+    @pytest.mark.parametrize(
+        "axis,arith", product((0, 1), ("add", "sub", "mul", "mod", "truediv"))
+    )
+    def test_frame_series_axis(self, axis, arith):
+        # Can't check floordiv here because it currently doesn't work #GH27636
+        df = self.frame
+        if axis == 1:
+            other = self.frame.iloc[0, :]
+        else:
+            other = self.frame.iloc[:, 0]
+
+        expr._MIN_ELEMENTS = 0
+
+        op = lambda x, y: getattr(x, arith)(y, axis=axis)
+        op.__name__ = arith
+
+        expr.set_use_numexpr(False)
+        expected = op(df, other)
+        expr.set_use_numexpr(True)
+
+        result = op(df, other)
+        try:
+            assert_frame_equal(expected, result)
+        except Exception:
+            pprint_thing("Failed test with operator {op.__name__!r}".format(op=op))
+            raise