Fixed #34681 -- Optimized memcache_key_warnings().

1 files changed, 9 insertions, 7 deletions

diff --git a/django/core/cache/backends/base.py b/django/core/cache/backends/base.py
index eb4b3eac6d..09b0a5f9c8 100644
--- a/django/core/cache/backends/base.py
+++ b/django/core/cache/backends/base.py
@@ -6,6 +6,7 @@ from asgiref.sync import sync_to_async
 
 from django.core.exceptions import ImproperlyConfigured
 from django.utils.module_loading import import_string
+from django.utils.regex_helper import _lazy_re_compile
 
 
 class InvalidCacheBackendError(ImproperlyConfigured):
@@ -388,16 +389,17 @@ class BaseCache:
         pass
 
 
+memcached_error_chars_re = _lazy_re_compile(r"[\x00-\x20\x7f]")
+
+
 def memcache_key_warnings(key):
     if len(key) > MEMCACHE_MAX_KEY_LENGTH:
         yield (
             "Cache key will cause errors if used with memcached: %r "
             "(longer than %s)" % (key, MEMCACHE_MAX_KEY_LENGTH)
         )
-    for char in key:
-        if ord(char) < 33 or ord(char) == 127:
-            yield (
-                "Cache key contains characters that will cause errors if "
-                "used with memcached: %r" % key
-            )
-            break
+    if memcached_error_chars_re.search(key):
+        yield (
+            "Cache key contains characters that will cause errors if used with "
+            f"memcached: {key!r}"
+        )