From c33144a3ef4e1af56e04ffc2a1b43c01c070c8a8 Mon Sep 17 00:00:00 2001
From: Irit Katriel <iritkatriel@yahoo.com>
Date: Fri, 10 Feb 2023 15:49:06 +0000
Subject: [PATCH 1/2] gh-101517: bdb should not lookup linecache with
 lineno=None

---
 Lib/bdb.py           | 7 ++++---
 Lib/test/test_bdb.py | 6 ++++++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/Lib/bdb.py b/Lib/bdb.py
index 81fbb8514acb6f..7f9b09514ffd00 100644
--- a/Lib/bdb.py
+++ b/Lib/bdb.py
@@ -570,9 +570,10 @@ def format_stack_entry(self, frame_lineno, lprefix=': '):
             rv = frame.f_locals['__return__']
             s += '->'
             s += reprlib.repr(rv)
-        line = linecache.getline(filename, lineno, frame.f_globals)
-        if line:
-            s += lprefix + line.strip()
+        if lineno is not None:
+            line = linecache.getline(filename, lineno, frame.f_globals)
+            if line:
+                s += lprefix + line.strip()
         return s
 
     # The following methods can be called by clients to use
diff --git a/Lib/test/test_bdb.py b/Lib/test/test_bdb.py
index 87a5ac308a12df..042c2daea7f797 100644
--- a/Lib/test/test_bdb.py
+++ b/Lib/test/test_bdb.py
@@ -1203,5 +1203,11 @@ def main():
                 tracer.runcall(tfunc_import)
 
 
+class TestRegressions(unittest.TestCase):
+    def test_format_stack_entry_no_lineno(self):
+        # See gh-101517
+        Bdb().format_stack_entry((sys._getframe(), None))
+
+
 if __name__ == "__main__":
     unittest.main()

From 8d770b19254d53ca1260361ede11073331eb153a Mon Sep 17 00:00:00 2001
From: "blurb-it[bot]" <43283697+blurb-it[bot]@users.noreply.github.com>
Date: Fri, 10 Feb 2023 16:02:32 +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/2023-02-10-16-02-29.gh-issue-101517.r7S2u8.rst  | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 Misc/NEWS.d/next/Library/2023-02-10-16-02-29.gh-issue-101517.r7S2u8.rst

diff --git a/Misc/NEWS.d/next/Library/2023-02-10-16-02-29.gh-issue-101517.r7S2u8.rst b/Misc/NEWS.d/next/Library/2023-02-10-16-02-29.gh-issue-101517.r7S2u8.rst
new file mode 100644
index 00000000000000..a5f6bdfa5ac2f0
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-02-10-16-02-29.gh-issue-101517.r7S2u8.rst
@@ -0,0 +1 @@
+Fixed bug where :mod:`bdb` looks up the source line with :mod:`linecache` with a ``lineno=None``, which causes it to fail with an unhandled exception.