BUG: series comp non-object dtype does not raise error on diff length

Author: changhiskhan

pandas/core/series.py

@@ -117,6 +117,10 @@ def na_op(x, y):
             else:
                 result = lib.scalar_compare(x, y, op)
         else:
+            if (isinstance(x, np.ndarray) and
+                isinstance(y, np.ndarray) and
+                len(x) != len(y)):
+                raise ValueError('Array lengths must equal to compare')
             result = op(x, y)
 
         return result

pandas/tests/test_series.py

@@ -1598,6 +1598,10 @@ def test_comparison_different_length(self):
         b = Series(['b', 'a'])
         self.assertRaises(ValueError, a.__lt__, b)
 
+        a = Series([1, 2])
+        b = Series([2, 3, 4])
+        self.assertRaises(ValueError, a.__eq__, b)
+
     def test_between(self):
         s = Series(bdate_range('1/1/2000', periods=20).asobject)
         s[::2] = np.nan