From 51a9f161dfb10540f9f93cb0708be49574a9f14f Mon Sep 17 00:00:00 2001
From: Antony Lee <anntzer.lee@gmail.com>
Date: Thu, 21 Jul 2022 21:07:02 +0200
Subject: [PATCH] Tweak Axes repr.

... by putting spaces where expected in normal style.  Also slightly
refactor the implementation.
---
 lib/matplotlib/axes/_base.py           | 14 +++++++-------
 lib/matplotlib/tests/test_axes.py      |  7 ++++---
 lib/mpl_toolkits/tests/test_mplot3d.py |  6 +++---
 3 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
index 5717b1f1d17f..7f917ab6cbdd 100644
--- a/lib/matplotlib/axes/_base.py
+++ b/lib/matplotlib/axes/_base.py
@@ -724,18 +724,18 @@ def __repr__(self):
         fields = []
         if self.get_label():
             fields += [f"label={self.get_label()!r}"]
-        titles = []
-        for k in ["left", "center", "right"]:
-            if hasattr(self, 'get_title'):
+        if hasattr(self, "get_title"):
+            titles = {}
+            for k in ["left", "center", "right"]:
                 title = self.get_title(loc=k)
                 if title:
-                    titles.append(f"{k!r}:{title!r}")
-        if titles:
-            fields += ["title={" + ",".join(titles) + "}"]
+                    titles[k] = title
+            if titles:
+                fields += [f"title={titles}"]
         for name, axis in self._axis_map.items():
             if axis.get_label() and axis.get_label().get_text():
                 fields += [f"{name}label={axis.get_label().get_text()!r}"]
-        return f"<{self.__class__.__name__}:" + ", ".join(fields) + ">"
+        return f"<{self.__class__.__name__}: " + ", ".join(fields) + ">"
 
     @_api.delete_parameter("3.6", "args")
     @_api.delete_parameter("3.6", "kwargs")
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
index 329af83ab873..721e35768265 100644
--- a/lib/matplotlib/tests/test_axes.py
+++ b/lib/matplotlib/tests/test_axes.py
@@ -65,8 +65,9 @@ def test_repr():
     ax.set_title('title')
     ax.set_xlabel('x')
     ax.set_ylabel('y')
-    assert repr(ax) == ("<AxesSubplot:label='label', " +
-                        "title={'center':'title'}, xlabel='x', ylabel='y'>")
+    assert repr(ax) == (
+        "<AxesSubplot: "
+        "label='label', title={'center': 'title'}, xlabel='x', ylabel='y'>")
 
 
 @check_figures_equal()
@@ -7046,7 +7047,7 @@ def test_secondary_formatter():
 def test_secondary_repr():
     fig, ax = plt.subplots()
     secax = ax.secondary_xaxis("top")
-    assert repr(secax) == '<SecondaryAxis:>'
+    assert repr(secax) == '<SecondaryAxis: >'
 
 
 def color_boxes(fig, ax):
diff --git a/lib/mpl_toolkits/tests/test_mplot3d.py b/lib/mpl_toolkits/tests/test_mplot3d.py
index 7df8fa3ac2d8..1024444df2ca 100644
--- a/lib/mpl_toolkits/tests/test_mplot3d.py
+++ b/lib/mpl_toolkits/tests/test_mplot3d.py
@@ -42,9 +42,9 @@ def test_axes3d_repr():
     ax.set_xlabel('x')
     ax.set_ylabel('y')
     ax.set_zlabel('z')
-    assert repr(ax) == ("<Axes3DSubplot:label='label', " +
-                        "title={'center':'title'}, " +
-                        "xlabel='x', ylabel='y', zlabel='z'>")
+    assert repr(ax) == (
+        "<Axes3DSubplot: label='label', "
+        "title={'center': 'title'}, xlabel='x', ylabel='y', zlabel='z'>")
 
 
 @mpl3d_image_comparison(['bar3d.png'])