🔀 fix conflicts, fix nameerror in tests

Author: Marco Gorelli

doc/source/whatsnew/v1.0.0.rst

@@ -300,38 +300,40 @@ New repr for :class:`~pandas.arrays.IntervalArray`
 
    pd.arrays.IntervalArray.from_tuples([(0, 1), (2, 3)])
 
-``DataFrame.rename`` now only accepts one positional argument
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-- :meth:`DataFrame.rename` would previously accept positional arguments that would lead
-  to ambiguous or undefined behavior. From pandas 1.0, only the very first argument, which
-  maps labels to their new names along the default axis, is allowed to be passed by position
-  (:issue:`29136`).
-- :meth:`DataFrame.merge` now preserves right frame's row order when executing a right merge (:issue:`27453`)
 :meth:`DataFrame.merge` preserves right frame's row order
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 :meth:`DataFrame.merge` now preserves right frame's row order when executing a right merge (:issue:`27453`)
 
-.. code-block:: python
+.. ipython:: python
 
-    left_df = pd.DataFrame({"colors": ["blue", "red"]}, index=pd.Index([0, 1]))
-    right_df = pd.DataFrame({"hats": ["small", "big"]}, index=pd.Index([1, 0]))
+    left_df = pd.DataFrame({'animal': ['dog', 'pig'], 'max_speed': [40, 11]})
+    right_df = pd.DataFrame({'animal': ['quetzal', 'pig'], 'max_speed': [80, 11]})
     left_df
     right_df
 
 *pandas 0.25.x*
 
 .. code-block:: python
-    left_df.merge(right_df, left_index=True, right_index=True, how="right")
+
+    >>> left_df.merge(right_df, on=['animal', 'max_speed'], how="right")                           
+        animal  max_speed
+    0      pig         11
+    1  quetzal         80
 
 
 *pandas 1.0.0*
 
-.. code-block:: python
-    left_df.merge(right_df, left_index=True, right_index=True, how="right")
+.. ipython:: python
 
+    left_df.merge(right_df, on=['animal', 'max_speed'], how="right")
 
+``DataFrame.rename`` now only accepts one positional argument
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+- :meth:`DataFrame.rename` would previously accept positional arguments that would lead
+  to ambiguous or undefined behavior. From pandas 1.0, only the very first argument, which
+  maps labels to their new names along the default axis, is allowed to be passed by position
+  (:issue:`29136`).
 
 *pandas 0.25.x*
 
@@ -1179,13 +1181,9 @@ Reshaping
 - Bug in :func:`melt` where supplying mixed strings and numeric values for ``id_vars`` or ``value_vars`` would incorrectly raise a ``ValueError`` (:issue:`29718`)
 - Dtypes are now preserved when transposing a ``DataFrame`` where each column is the same extension dtype (:issue:`30091`)
 - Bug in :func:`merge_asof` merging on a tz-aware ``left_index`` and ``right_on`` a tz-aware column (:issue:`29864`)
-<<<<<<< HEAD
 - Improved error message and docstring in :func:`cut` and :func:`qcut` when `labels=True` (:issue:`13318`)
 - Bug in missing `fill_na` parameter to :meth:`DataFrame.unstack` with list of levels (:issue:`30740`)
 - :meth:`DataFrame.merge` now preserves right frame's row order when executing a right merge (:issue:`27453`)
-=======
->>>>>>> 2b1b67592... changes requested by jreback
--
 
 Sparse
 ^^^^^^

pandas/core/reshape/merge.py

@@ -568,10 +568,10 @@ def __init__(
         indicator: bool = False,
         validate=None,
     ):
-        left = validate_operand(left)
-        right = validate_operand(right)
-        self.left = self.orig_left = left
-        self.right = self.orig_right = right
+        _left = _validate_operand(left)
+        _right = _validate_operand(right)
+        self.left = self.orig_left = _left
+        self.right = self.orig_right = _right
         self.how = how
         self.axis = axis
 

pandas/tests/reshape/merge/test_merge.py

@@ -2194,34 +2194,6 @@ def test_merge_preserves_row_order(how):
     expected_cols = ["name", "country", "population"]
     expected = DataFrame(expected_data, columns=expected_cols)
 
-    result = pop.merge(ppl, on=("name", "country"), how="right")
-
-    tm.assert_frame_equal(result, expected)
-
-
-def test_left_merge_preserves_row_order():
-    # GH 27453
-    population = [
-        ("Jenn", "Jamaica", 3),
-        ("Beth", "Bulgaria", 7),
-        ("Carl", "Canada", 30),
-    ]
-    columns = ["name", "country", "population"]
-    pop = DataFrame(population, columns=columns)
-
-    people = [("Abe", "America"), ("Beth", "Bulgaria"), ("Carl", "Canada")]
-    columns = ["name", "country"]
-    ppl = DataFrame(people, columns=columns)
-
-    expected_data = [
-        ("Abe", "America", np.nan),
-        ("Beth", "Bulgaria", 7),
-        ("Carl", "Canada", 30),
-    ]
-    expected_cols = ["name", "country", "population"]
-    expected = DataFrame(expected_data, columns=expected_cols)
-
-    result = ppl.merge(pop, on=("name", "country"), how="left")
     if how == "right":
         left_df, right_df = population_df, people_df
     elif how == "left":