From 6eaca5da4f46fb2d6e04d775fc87fad00d018280 Mon Sep 17 00:00:00 2001
From: Sarah Boyce <42296566+sarahboyce@users.noreply.github.com>
Date: Fri, 11 Oct 2024 13:44:12 +0200
Subject: [PATCH] Fixed #35998 -- Added caching to django.utils.html.urlize().

---
 django/utils/html.py                          | 16 +++++++-----
 .../filter_tests/test_urlize.py               | 25 +++++++++++++++++++
 2 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/django/utils/html.py b/django/utils/html.py
index 0d107a0da9..5b795accd6 100644
--- a/django/utils/html.py
+++ b/django/utils/html.py
@@ -317,18 +317,22 @@ class Urlizer:
         safe_input = isinstance(text, SafeData)
 
         words = self.word_split_re.split(str(text))
-        return "".join(
-            [
-                self.handle_word(
+        mapping = {}
+        urlized_words = []
+        for word in words:
+            if word in mapping:
+                urlized_words.append(mapping[word])
+            else:
+                urlized_word = self.handle_word(
                     word,
                     safe_input=safe_input,
                     trim_url_limit=trim_url_limit,
                     nofollow=nofollow,
                     autoescape=autoescape,
                 )
-                for word in words
-            ]
-        )
+                urlized_words.append(urlized_word)
+                mapping[word] = urlized_word
+        return "".join(urlized_words)
 
     def handle_word(
         self,
diff --git a/tests/template_tests/filter_tests/test_urlize.py b/tests/template_tests/filter_tests/test_urlize.py
index 546bd6c7d6..a415c59328 100644
--- a/tests/template_tests/filter_tests/test_urlize.py
+++ b/tests/template_tests/filter_tests/test_urlize.py
@@ -1,6 +1,9 @@
+from unittest import mock
+
 from django.template.defaultfilters import urlize
 from django.test import SimpleTestCase
 from django.utils.functional import lazy
+from django.utils.html import Urlizer
 from django.utils.safestring import mark_safe
 
 from ..utils import setup
@@ -467,3 +470,25 @@ class FunctionTests(SimpleTestCase):
             urlize(prepend_www("google.com")),
             '<a href="http://www.google.com" rel="nofollow">www.google.com</a>',
         )
+
+    @mock.patch.object(Urlizer, "handle_word", return_value="test")
+    def test_caching(self, mock_handle_word):
+        urlize("test test test test")
+        mock_handle_word.assert_has_calls(
+            [
+                mock.call(
+                    "test",
+                    safe_input=False,
+                    trim_url_limit=None,
+                    nofollow=True,
+                    autoescape=True,
+                ),
+                mock.call(
+                    " ",
+                    safe_input=False,
+                    trim_url_limit=None,
+                    nofollow=True,
+                    autoescape=True,
+                ),
+            ]
+        )