BUG: Series.where always inplace

Author: changhiskhan

pandas/core/series.py

@@ -585,8 +585,8 @@ def where(self, cond, other=nan, inplace=False):
 
         ser = self if inplace else self.copy()
         if not isinstance(other, (list, tuple, np.ndarray)):
-            self._set_with(~cond, other)
-            return self
+            ser._set_with(~cond, other)
+            return ser
 
         if isinstance(other, Series):
             other = other.reindex(ser.index)

pandas/tests/test_series.py

@@ -952,6 +952,7 @@ def test_where(self):
 
         rs  = s.where(cond)
         assert(s.shape == rs.shape)
+        assert(rs is not s)
 
         rs = s.where(cond[:3], -s)
         assert_series_equal(rs, s.abs()[:3].append(s[3:]))