API/DEPR: replace "raise_conflict" with "errors" for df.update

doc/source/whatsnew/v0.24.0.txt

@@ -973,6 +973,7 @@ Deprecations
 - The ``fastpath`` keyword of the different Index constructors is deprecated (:issue:`23110`).
 - :meth:`Timestamp.tz_localize`, :meth:`DatetimeIndex.tz_localize`, and :meth:`Series.tz_localize` have deprecated the ``errors`` argument in favor of the ``nonexistent`` argument (:issue:`8917`)
 - The class ``FrozenNDArray`` has been deprecated. When unpickling, ``FrozenNDArray`` will be unpickled to ``np.ndarray`` once this class is removed (:issue:`9031`)
+- The methods :meth:`DataFrame.update` and :meth:`Panel.update` have deprecated the ``raise_conflict=False|True`` keyword in favor of ``errors='ignore'|'raise'`` (:issue:`23585`)
 - Deprecated the `nthreads` keyword of :func:`pandas.read_feather` in favor of
   `use_threads` to reflect the changes in pyarrow 0.11.0. (:issue:`23053`)
 - :func:`pandas.read_excel` has deprecated accepting ``usecols`` as an integer. Please pass in a list of ints from 0 to ``usecols`` inclusive instead (:issue:`23527`)

pandas/core/frame.py

@@ -5230,8 +5230,10 @@ def combiner(x, y):
 
         return self.combine(other, combiner, overwrite=False)
 
+    @deprecate_kwarg(old_arg_name='raise_conflict', new_arg_name='errors',
+                     mapping={False: 'ignore', True: 'raise'})
     def update(self, other, join='left', overwrite=True, filter_func=None,
-               raise_conflict=False):
+               errors='ignore'):
         """
         Modify in place using non-NA values from another DataFrame.
 
@@ -5255,17 +5257,21 @@ def update(self, other, join='left', overwrite=True, filter_func=None,
             * False: only update values that are NA in
               the original DataFrame.
 
-        filter_func : callable(1d-array) -> boolean 1d-array, optional
+        filter_func : callable(1d-array) -> bool 1d-array, optional
             Can choose to replace values other than NA. Return True for values
             that should be updated.
-        raise_conflict : bool, default False
-            If True, will raise a ValueError if the DataFrame and `other`
+        errors : {'raise', 'ignore'}, default 'ignore'
+            If 'raise', will raise a ValueError if the DataFrame and `other`
             both contain non-NA data in the same place.
 
+        Returns
+        -------
+        None : method directly changes calling object
+
         Raises
         ------
         ValueError
-            When `raise_conflict` is True and there's overlapping non-NA data.
+            When `errors='raise'` and there's overlapping non-NA data.
 
         See Also
         --------
@@ -5349,7 +5355,7 @@ def update(self, other, join='left', overwrite=True, filter_func=None,
                 with np.errstate(all='ignore'):
                     mask = ~filter_func(this) | isna(that)
             else:
-                if raise_conflict:
+                if errors == 'raise':
                     mask_this = notna(that)
                     mask_that = notna(this)
                     if any(mask_this & mask_that):

pandas/core/panel.py

@@ -32,7 +32,7 @@
                                    create_block_manager_from_blocks)
 from pandas.core.series import Series
 from pandas.core.reshape.util import cartesian_product
-from pandas.util._decorators import Appender, Substitution
+from pandas.util._decorators import Appender, Substitution, deprecate_kwarg
 from pandas.util._validators import validate_axis_style_args
 
 _shared_doc_kwargs = dict(
@@ -1235,7 +1235,12 @@ def reindex(self, *args, **kwargs):
         kwargs.update(axes)
         kwargs.pop('axis', None)
         kwargs.pop('labels', None)
-        return super(Panel, self).reindex(**kwargs)
+
+        with warnings.catch_warnings():
+            warnings.simplefilter("ignore", FutureWarning)
+            # do not warn about constructing Panel when reindexing
+            result = super(Panel, self).reindex(**kwargs)
+        return result
 
     @Substitution(**_shared_doc_kwargs)
     @Appender(NDFrame.rename.__doc__)
@@ -1377,25 +1382,33 @@ def join(self, other, how='left', lsuffix='', rsuffix=''):
             return concat([self] + list(other), axis=0, join=how,
                           join_axes=join_axes, verify_integrity=True)
 
+    @deprecate_kwarg(old_arg_name='raise_conflict', new_arg_name='errors',
+                     mapping={False: 'ignore', True: 'raise'})
     def update(self, other, join='left', overwrite=True, filter_func=None,
-               raise_conflict=False):
+               errors='ignore'):
         """
-        Modify Panel in place using non-NA values from passed
-        Panel, or object coercible to Panel. Aligns on items
+        Modify Panel in place using non-NA values from other Panel.
+
+        May also use object coercible to Panel. Will align on items.
 
         Parameters
         ----------
         other : Panel, or object coercible to Panel
-        join : How to join individual DataFrames
-            {'left', 'right', 'outer', 'inner'}, default 'left'
-        overwrite : boolean, default True
-            If True then overwrite values for common keys in the calling panel
-        filter_func : callable(1d-array) -> 1d-array<boolean>, default None
+            The object from which the caller will be udpated.
+        join : {'left', 'right', 'outer', 'inner'}, default 'left'
+            How individual DataFrames are joined.
+        overwrite : bool, default True
+            If True then overwrite values for common keys in the calling Panel.
+        filter_func : callable(1d-array) -> 1d-array<bool>, default None
             Can choose to replace values other than NA. Return True for values
-            that should be updated
-        raise_conflict : bool
-            If True, will raise an error if a DataFrame and other both
-            contain data in the same place.
+            that should be updated.
+        errors : {'raise', 'ignore'}, default 'ignore'
+            If 'raise', will raise an error if a DataFrame and other both.
+
+        See Also
+        --------
+        DataFrame.update : Similar method for DataFrames.
+        dict.update : Similar method for dictionaries.
         """
 
         if not isinstance(other, self._constructor):
@@ -1406,8 +1419,8 @@ def update(self, other, join='left', overwrite=True, filter_func=None,
         other = other.reindex(**{axis_name: axis_values})
 
         for frame in axis_values:
-            self[frame].update(other[frame], join, overwrite, filter_func,
-                               raise_conflict)
+            self[frame].update(other[frame], join=join, overwrite=overwrite,
+                               filter_func=filter_func, errors=errors)
 
     def _get_join_index(self, other, how):
         if how == 'left':

pandas/tests/frame/test_combine_concat.py

@@ -322,7 +322,9 @@ def test_update_raise(self):
         other = DataFrame([[2., nan],
                            [nan, 7]], index=[1, 3], columns=[1, 2])
         with pytest.raises(ValueError, match="Data overlaps"):
-            df.update(other, raise_conflict=True)
+            df.update(other, errors='raise')
+        with tm.assert_produces_warning(FutureWarning):
+            df.update(other, raise_conflict=False)
 
     def test_update_from_non_df(self):
         d = {'a': Series([1, 2, 3, 4]), 'b': Series([5, 6, 7, 8])}

pandas/tests/test_panel.py

@@ -2348,9 +2348,12 @@ def test_update_raise(self):
                      [[1.5, np.nan, 3.], [1.5, np.nan, 3.],
                       [1.5, np.nan, 3.],
                       [1.5, np.nan, 3.]]])
+        other = Panel([[[]]])
 
-        pytest.raises(Exception, pan.update, *(pan, ),
-                      **{'raise_conflict': True})
+        with pytest.raises(ValueError, match='Data overlaps'):
+            pan.update(pan, errors='raise')
+        with tm.assert_produces_warning(FutureWarning):
+            pan.update(other, raise_conflict=True)
 
     def test_all_any(self):
         assert (self.panel.all(axis=0).values == nanall(