From 3bb30729afa55f636d31afbaa5155740394de297 Mon Sep 17 00:00:00 2001
From: Aaron <aaron@framelunch.jp>
Date: Fri, 24 Mar 2023 04:24:27 +0900
Subject: [PATCH 1/2] bufix for issue-102967

---
 Lib/doctest.py | 3 ++-
 Misc/ACKS      | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/Lib/doctest.py b/Lib/doctest.py
index 2776d74bf9b586..51bdd2f381e848 100644
--- a/Lib/doctest.py
+++ b/Lib/doctest.py
@@ -270,7 +270,8 @@ def getvalue(self):
         return result
 
     def truncate(self, size=None):
-        self.seek(size)
+        if size != None:
+            self.seek(size)
         StringIO.truncate(self)
 
 # Worst-case linear-time ellipsis matching.
diff --git a/Misc/ACKS b/Misc/ACKS
index 8cf5166a2bb1f4..2a1d0181452c7b 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -406,6 +406,7 @@ Lars Damerow
 Evan Dandrea
 Eric Daniel
 Scott David Daniels
+Aaron Davidson
 Derzsi Dániel
 Lawrence D'Anna
 Ben Darnell

From 8d4e729bf8f80337a40c80f28d256b65b13ffc2a Mon Sep 17 00:00:00 2001
From: "blurb-it[bot]" <43283697+blurb-it[bot]@users.noreply.github.com>
Date: Thu, 23 Mar 2023 19:47:06 +0000
Subject: [PATCH 2/2] =?UTF-8?q?=F0=9F=93=9C=F0=9F=A4=96=20Added=20by=20blu?=
 =?UTF-8?q?rb=5Fit.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../next/Library/2023-03-23-19-47-05.gh-issue-102967.gfIYkN.rst | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2023-03-23-19-47-05.gh-issue-102967.gfIYkN.rst

diff --git a/Misc/NEWS.d/next/Library/2023-03-23-19-47-05.gh-issue-102967.gfIYkN.rst b/Misc/NEWS.d/next/Library/2023-03-23-19-47-05.gh-issue-102967.gfIYkN.rst
new file mode 100644
index 00000000000000..bcece939531869
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-03-23-19-47-05.gh-issue-102967.gfIYkN.rst
@@ -0,0 +1,2 @@
+A bug in :func:`doctest._SpoofOut.truncate` was causing None to be passed to :func:`StringIO.seek` when no size was given.
+A simple fix skips the seek call when no size is given so the buffer can be truncated from the current position.