From e85a17d8c3524b61416440c520df49d3db695a49 Mon Sep 17 00:00:00 2001
From: Tim Hoffmann <2836374+timhoffm@users.noreply.github.com>
Date: Mon, 25 May 2020 00:51:42 +0200
Subject: [PATCH] Undocument parameter orientation of bar()

---
 lib/matplotlib/axes/_axes.py      | 7 +++----
 lib/matplotlib/tests/test_axes.py | 2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
index e41cfba674e7..cc36b6871778 100644
--- a/lib/matplotlib/axes/_axes.py
+++ b/lib/matplotlib/axes/_axes.py
@@ -2351,10 +2351,6 @@ def bar(self, x, height, width=0.8, bottom=None, *, align="center",
         log : bool, default: False
             If *True*, set the y-axis to be log scale.
 
-        orientation : {'vertical',  'horizontal'}, optional
-            *This is for internal use only.* Please use `barh` for
-            horizontal bar plots. Default: 'vertical'.
-
         **kwargs : `.Rectangle` properties
 
         %(Rectangle)s
@@ -2393,6 +2389,9 @@ def bar(self, x, height, width=0.8, bottom=None, *, align="center",
         error_kw.setdefault('ecolor', ecolor)
         error_kw.setdefault('capsize', capsize)
 
+        # The keyword argument *orientation* is used by barh() to defer all
+        # logic and drawing to bar(). It is considered internal and is
+        # intentionally not mentioned in the docstring.
         orientation = kwargs.pop('orientation', 'vertical')
         cbook._check_in_list(['vertical', 'horizontal'],
                              orientation=orientation)
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
index dfb2450836f2..b8930ccdfba0 100644
--- a/lib/matplotlib/tests/test_axes.py
+++ b/lib/matplotlib/tests/test_axes.py
@@ -5495,7 +5495,7 @@ def test_bar_broadcast_args():
     # Check that a bar chart with a single height for all bars works.
     ax.bar(range(4), 1)
     # Check that a horizontal chart with one width works.
-    ax.bar(0, 1, bottom=range(4), width=1, orientation='horizontal')
+    ax.barh(0, 1, left=range(4), height=1)
     # Check that edgecolor gets broadcast.
     rect1, rect2 = ax.bar([0, 1], [0, 1], edgecolor=(.1, .2, .3, .4))
     assert rect1.get_edgecolor() == rect2.get_edgecolor() == (.1, .2, .3, .4)