From 85716d2a7a0b2d5c30695e9e4b4273d2d4cf8ef3 Mon Sep 17 00:00:00 2001
From: LloydZ <35182391+cocolato@users.noreply.github.com>
Date: Tue, 2 Dec 2025 12:41:54 +0800
Subject: [PATCH 1/2] [3.13] gh-59000: Fix pdb breakpoint resolution for class
 methods when module not imported (GH-141949) (cherry picked from commit
 5e58548ebe8f7ac8c6cb0bad775912caa4090515)

Co-authored-by: LloydZ <35182391+cocolato@users.noreply.github.com>
---
 Lib/pdb.py                                    |  4 +-
 Lib/test/test_pdb.py                          | 48 +++++++++++++++++++
 ...5-11-25-16-00-29.gh-issue-59000.YtOyJy.rst |  1 +
 3 files changed, 52 insertions(+), 1 deletion(-)
 create mode 100644 Misc/NEWS.d/next/Library/2025-11-25-16-00-29.gh-issue-59000.YtOyJy.rst

diff --git a/Lib/pdb.py b/Lib/pdb.py
index a990d60fe1c2fd..063b12cc856c21 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -1262,7 +1262,9 @@ def lineinfo(self, identifier):
             f = self.lookupmodule(parts[0])
             if f:
                 fname = f
-            item = parts[1]
+                item = parts[1]
+            else:
+                return failed
         answer = find_function(item, self.canonic(fname))
         return answer or failed
 
diff --git a/Lib/test/test_pdb.py b/Lib/test/test_pdb.py
index 92a0180ecc9a06..a4b9ae2ca1789e 100644
--- a/Lib/test/test_pdb.py
+++ b/Lib/test/test_pdb.py
@@ -4013,6 +4013,54 @@ def f(x):
             self.assertIn('42', stdout)
             self.assertIn('return x + 1', stdout)
 
+    def test_zipimport(self):
+        with os_helper.temp_dir() as temp_dir:
+            os.mkdir(os.path.join(temp_dir, 'source'))
+            zipmodule = textwrap.dedent(
+                """
+                def bar():
+                    pass
+                """
+            )
+            script = textwrap.dedent(
+                f"""
+                import sys; sys.path.insert(0, {repr(os.path.join(temp_dir, 'zipmodule.zip'))})
+                import foo
+                foo.bar()
+                """
+            )
+
+            with zipfile.ZipFile(os.path.join(temp_dir, 'zipmodule.zip'), 'w') as zf:
+                zf.writestr('foo.py', zipmodule)
+            with open(os.path.join(temp_dir, 'script.py'), 'w') as f:
+                f.write(script)
+
+            stdout, _ = self._run_pdb([os.path.join(temp_dir, 'script.py')], '\n'.join([
+                'n',
+                'n',
+                'b foo.bar',
+                'c',
+                'p f"break in {$_frame.f_code.co_name}"',
+                'q'
+            ]))
+            self.assertIn('break in bar', stdout)
+
+    def test_issue_59000(self):
+        script = """
+            def foo():
+                pass
+
+            class C:
+                def foo(self):
+                    pass
+        """
+        commands = """
+            break C.foo
+            quit
+        """
+        stdout, stderr = self.run_pdb_script(script, commands)
+        self.assertIn("The specified object 'C.foo' is not a function", stdout)
+
 
 class ChecklineTests(unittest.TestCase):
     def setUp(self):
diff --git a/Misc/NEWS.d/next/Library/2025-11-25-16-00-29.gh-issue-59000.YtOyJy.rst b/Misc/NEWS.d/next/Library/2025-11-25-16-00-29.gh-issue-59000.YtOyJy.rst
new file mode 100644
index 00000000000000..33ab8a0659e4a2
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-11-25-16-00-29.gh-issue-59000.YtOyJy.rst
@@ -0,0 +1 @@
+Fix :mod:`pdb` breakpoint resolution for class methods when the module defining the class is not imported.

From 2365035500dbb22672243529291b7e1da19542df Mon Sep 17 00:00:00 2001
From: Tian Gao <gaogaotiantian@hotmail.com>
Date: Mon, 1 Dec 2025 20:44:52 -0800
Subject: [PATCH 2/2] Remove test_zipimport method

Removed the test_zipimport method from test_pdb.py.
---
 Lib/test/test_pdb.py | 32 --------------------------------
 1 file changed, 32 deletions(-)

diff --git a/Lib/test/test_pdb.py b/Lib/test/test_pdb.py
index a4b9ae2ca1789e..dd31649ab262c3 100644
--- a/Lib/test/test_pdb.py
+++ b/Lib/test/test_pdb.py
@@ -4013,38 +4013,6 @@ def f(x):
             self.assertIn('42', stdout)
             self.assertIn('return x + 1', stdout)
 
-    def test_zipimport(self):
-        with os_helper.temp_dir() as temp_dir:
-            os.mkdir(os.path.join(temp_dir, 'source'))
-            zipmodule = textwrap.dedent(
-                """
-                def bar():
-                    pass
-                """
-            )
-            script = textwrap.dedent(
-                f"""
-                import sys; sys.path.insert(0, {repr(os.path.join(temp_dir, 'zipmodule.zip'))})
-                import foo
-                foo.bar()
-                """
-            )
-
-            with zipfile.ZipFile(os.path.join(temp_dir, 'zipmodule.zip'), 'w') as zf:
-                zf.writestr('foo.py', zipmodule)
-            with open(os.path.join(temp_dir, 'script.py'), 'w') as f:
-                f.write(script)
-
-            stdout, _ = self._run_pdb([os.path.join(temp_dir, 'script.py')], '\n'.join([
-                'n',
-                'n',
-                'b foo.bar',
-                'c',
-                'p f"break in {$_frame.f_code.co_name}"',
-                'q'
-            ]))
-            self.assertIn('break in bar', stdout)
-
     def test_issue_59000(self):
         script = """
             def foo():