gh-120367: fix removal of redundant NOPs and jumps after reordering hot-cold blocks (#120425)

1 files changed, 27 insertions, 0 deletions

diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py
index ae23aea..219314b 100644
--- a/Lib/test/test_compile.py
+++ b/Lib/test/test_compile.py
@@ -502,6 +502,33 @@ class TestSpecifics(unittest.TestCase):
         with self.assertRaisesRegex(TypeError, "NamedExpr target must be a Name"):
             compile(ast.fix_missing_locations(m), "<file>", "exec")
 
+    def test_compile_redundant_jumps_and_nops_after_moving_cold_blocks(self):
+        # See gh-120367
+        code=textwrap.dedent("""
+            try:
+                pass
+            except:
+                pass
+            else:
+                match name_2:
+                    case b'':
+                        pass
+            finally:
+                something
+            """)
+
+        tree = ast.parse(code)
+
+        # make all instructions locations the same to create redundancies
+        for node in ast.walk(tree):
+            if hasattr(node,"lineno"):
+                 del node.lineno
+                 del node.end_lineno
+                 del node.col_offset
+                 del node.end_col_offset
+
+        compile(ast.fix_missing_locations(tree), "<file>", "exec")
+
     def test_compile_ast(self):
         fname = __file__
         if fname.lower().endswith('pyc'):