From: Cody Maloney <cmaloney@users.noreply.github.com>
Date: Fri, 28 Nov 2025 17:46:10 +0000 (-0800)
Subject: gh-141968: Use take_bytes in re._compiler (#141995)
X-Git-Tag: v3.15.0a3~257
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3001464248edfba76fc23d4a8107dc24f2807d46;p=thirdparty%2FPython%2Fcpython.git

gh-141968: Use take_bytes in re._compiler (#141995)

Removes a copy going from bytearray to bytes.

Co-authored-by: Victor Stinner <vstinner@python.org>
Co-authored-by: Bénédikt Tran <10796600+picnixz@users.noreply.github.com>
---

diff --git a/Lib/re/_compiler.py b/Lib/re/_compiler.py
index 20dd561d1c15..c2ca8e25abe3 100644
--- a/Lib/re/_compiler.py
+++ b/Lib/re/_compiler.py
@@ -375,7 +375,7 @@ def _optimize_charset(charset, iscased=None, fixup=None, fixes=None):
     # less significant byte is a bit index in the chunk (just like the
     # CHARSET matching).
 
-    charmap = bytes(charmap) # should be hashable
+    charmap = charmap.take_bytes() # should be hashable
     comps = {}
     mapping = bytearray(256)
     block = 0
diff --git a/Misc/NEWS.d/next/Library/2025-11-26-14-20-10.gh-issue-141968.W139Pv.rst b/Misc/NEWS.d/next/Library/2025-11-26-14-20-10.gh-issue-141968.W139Pv.rst
new file mode 100644
index 000000000000..c5375707814f
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-11-26-14-20-10.gh-issue-141968.W139Pv.rst
@@ -0,0 +1,2 @@
+Remove data copy from :mod:`re` compilation of regexes with large charsets
+by using :meth:`bytearray.take_bytes`.