GH-91409: Don't overwrite valid locations with NOP locations (GH-95067)

Lib/test/test_compile.py

@@ -1202,6 +1202,44 @@ f(
         tree.body[0] = new_node
         compile(tree, "<test>", "exec")
 
+    def test_push_null_load_global_positions(self):
+        source_template = """
+        import abc, dis
+        import ast as art
+
+        abc = None
+        dix = dis
+        ast = art
+
+        def f():
+        {}
+        """
+        for body in [
+            "    abc.a()",
+            "    art.a()",
+            "    ast.a()",
+            "    dis.a()",
+            "    dix.a()",
+            "    abc[...]()",
+            "    art()()",
+            "   (ast or ...)()",
+            "   [dis]()",
+            "   (dix + ...)()",
+        ]:
+            with self.subTest(body):
+                namespace = {}
+                source = textwrap.dedent(source_template.format(body))
+                exec(source, namespace)
+                code = namespace["f"].__code__
+                self.assertOpcodeSourcePositionIs(
+                    code,
+                    "LOAD_GLOBAL",
+                    line=10,
+                    end_line=10,
+                    column=4,
+                    end_column=7,
+                )
+
 
 class TestExpressionStackSize(unittest.TestCase):
     # These tests check that the computed stack size for a code object