From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Fri, 6 Sep 2024 10:43:05 +0000 (+0200)
Subject: [3.12] gh-123048: Fix missing source location in pattern matching code (GH-123167... 
X-Git-Tag: v3.12.6~13
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=919a3e8028de61a57c672c2de1a47c82b75b2e39;p=thirdparty%2FPython%2Fcpython.git

[3.12] gh-123048: Fix missing source location in pattern matching code (GH-123167) (#123170)

gh-123048: Fix missing source location in pattern matching code (GH-123167)
(cherry picked from commit bffed80230f2617de2ee02bd4bdded1024234dab)

Co-authored-by: Irit Katriel <1055913+iritkatriel@users.noreply.github.com>
---

diff --git a/Lib/test/test_patma.py b/Lib/test/test_patma.py
index 3dbd19dfffd3..6fe5360b5f29 100644
--- a/Lib/test/test_patma.py
+++ b/Lib/test/test_patma.py
@@ -1,6 +1,7 @@
 import array
 import collections
 import dataclasses
+import dis
 import enum
 import inspect
 import sys
@@ -3083,6 +3084,24 @@ class TestValueErrors(unittest.TestCase):
         self.assertIs(y, None)
         self.assertIs(z, None)
 
+class TestSourceLocations(unittest.TestCase):
+    def test_jump_threading(self):
+        # See gh-123048
+        def f():
+            x = 0
+            v = 1
+            match v:
+                case 1:
+                    if x < 0:
+                        x = 1
+                case 2:
+                    if x < 0:
+                        x = 1
+            x += 1
+
+        for inst in dis.get_instructions(f):
+            if inst.opcode in dis.hasjrel or inst.opcode in dis.hasjabs:
+                self.assertIsNotNone(inst.positions.lineno, "jump without location")
 
 class TestTracing(unittest.TestCase):
 
diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-08-20-11-09-16.gh-issue-123048.2TISpv.rst b/Misc/NEWS.d/next/Core and Builtins/2024-08-20-11-09-16.gh-issue-123048.2TISpv.rst
new file mode 100644
index 000000000000..f0b756febbc1
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2024-08-20-11-09-16.gh-issue-123048.2TISpv.rst	
@@ -0,0 +1,2 @@
+Fix a bug where pattern matching code could emit a :opcode:`JUMP_FORWARD`
+with no source location.