COMPAT: Default for inplace is now False in eval

pandas-dev/pandas#11149

Author: TomAugspurger

dask/dataframe/core.py

@@ -2370,6 +2370,9 @@ def query(self, expr, **kwargs):
 
     @derived_from(pd.DataFrame)
     def eval(self, expr, inplace=None, **kwargs):
+        if inplace is None:
+            if PANDAS_VERSION > '0.21.0':
+                inplace = False
         if '=' in expr and inplace in (True, None):
             raise NotImplementedError("Inplace eval not supported."
                                       " Please use inplace=False")

dask/dataframe/tests/test_dataframe.py

@@ -1408,9 +1408,10 @@ def test_eval():
 
         # catch FutureWarning from pandas about assignment in eval
         with pytest.warns(None):
-            if p.eval('z = x + y', inplace=None) is None:
-                with pytest.raises(NotImplementedError):
-                    d.eval('z = x + y', inplace=None)
+            if PANDAS_VERSION < '0.21.0':
+                if p.eval('z = x + y', inplace=None) is None:
+                    with pytest.raises(NotImplementedError):
+                        d.eval('z = x + y', inplace=None)
 
 
 @pytest.mark.parametrize('include, exclude', [