From 7ac87cf3d96a2a6cf0ef95bea96d66821c51ce6e Mon Sep 17 00:00:00 2001
From: Thomas Roehr <roehr@simula.no>
Date: Wed, 26 Jul 2023 12:05:59 +0200
Subject: [PATCH 1/4] sklearn.tree: Fix validation of class_names argument for
 plot_tree

---
 sklearn/tree/_export.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sklearn/tree/_export.py b/sklearn/tree/_export.py
index 02f8ea81404c7..e84d806621991 100644
--- a/sklearn/tree/_export.py
+++ b/sklearn/tree/_export.py
@@ -79,7 +79,7 @@ def __repr__(self):
         "decision_tree": [DecisionTreeClassifier, DecisionTreeRegressor],
         "max_depth": [Interval(Integral, 0, None, closed="left"), None],
         "feature_names": [list, None],
-        "class_names": [list, None],
+        "class_names": ["array-like", "boolean", None],
         "label": [StrOptions({"all", "root", "none"})],
         "filled": ["boolean"],
         "impurity": ["boolean"],

From 4e284bac4a0f67e1b4e6e7d8f857b59c84878c60 Mon Sep 17 00:00:00 2001
From: Thomas Roehr <roehr@simula.no>
Date: Thu, 27 Jul 2023 08:55:44 +0200
Subject: [PATCH 2/4] sklearn.tree: update documentation of class_names for
 plot_tree

True is the only available boolean option
---
 sklearn/tree/_export.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sklearn/tree/_export.py b/sklearn/tree/_export.py
index e84d806621991..c89333aa49831 100644
--- a/sklearn/tree/_export.py
+++ b/sklearn/tree/_export.py
@@ -134,7 +134,7 @@ def plot_tree(
         Names of each of the features.
         If None, generic names will be used ("x[0]", "x[1]", ...).
 
-    class_names : list of str or bool, default=None
+    class_names : array-like of str or True, default=None
         Names of each of the target classes in ascending numerical order.
         Only relevant for classification and not supported for multi-output.
         If ``True``, shows a symbolic representation of the class name.

From a5a8afdbafeef361de22d7e247841f2ce3d29ff2 Mon Sep 17 00:00:00 2001
From: Thomas Roehr <roehr@simula.no>
Date: Thu, 27 Jul 2023 09:01:47 +0200
Subject: [PATCH 3/4] Add doc entry for fix

---
 doc/whats_new/v1.3.rst | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/doc/whats_new/v1.3.rst b/doc/whats_new/v1.3.rst
index 8d39ca2fed143..716d4c05241ac 100644
--- a/doc/whats_new/v1.3.rst
+++ b/doc/whats_new/v1.3.rst
@@ -758,6 +758,9 @@ Changelog
   `feature_names` and `class_names` as array-like rather than lists.
   :pr:`26289` by :user:`Yao Xiao <Charlie-XIAO>`
 
+- |Fix| :func:`tree.plot_tree` now accepts `class_names=True` as documented.
+  :pr:`26903` by :user:`Thomas Roehr <2maz>`
+
 :mod:`sklearn.utils`
 ....................
 

From ab3583c3cc7322cd8015813d8dbcf79248ac1518 Mon Sep 17 00:00:00 2001
From: "Thomas J. Fan" <thomasjpfan@gmail.com>
Date: Thu, 27 Jul 2023 09:41:30 -0400
Subject: [PATCH 4/4] DOC Move to 1.3.1

---
 doc/whats_new/v1.3.rst | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/doc/whats_new/v1.3.rst b/doc/whats_new/v1.3.rst
index 716d4c05241ac..e0df3c1beba4b 100644
--- a/doc/whats_new/v1.3.rst
+++ b/doc/whats_new/v1.3.rst
@@ -23,6 +23,12 @@ Changelog
   :attr:`sklearn.neighbors.KDTree.valid_metrics` as public class attributes.
   :pr:`26754` by :user:`Julien Jerphanion <jjerphan>`.
 
+:mod:`sklearn.tree`
+...................
+
+- |Fix| :func:`tree.plot_tree` now accepts `class_names=True` as documented.
+  :pr:`26903` by :user:`Thomas Roehr <2maz>`
+
 .. _changes_1_3:
 
 Version 1.3.0
@@ -758,9 +764,6 @@ Changelog
   `feature_names` and `class_names` as array-like rather than lists.
   :pr:`26289` by :user:`Yao Xiao <Charlie-XIAO>`
 
-- |Fix| :func:`tree.plot_tree` now accepts `class_names=True` as documented.
-  :pr:`26903` by :user:`Thomas Roehr <2maz>`
-
 :mod:`sklearn.utils`
 ....................