[GR-73107] Pattern matching: just fail on object attribute missing.

PullRequest: graalpython/4251

Author: medvecm98

graalpython/com.oracle.graal.python.test/src/tests/test_patmat.py

@@ -1,4 +1,4 @@
-# Copyright (c) 2022, 2025, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2022, 2026, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # The Universal Permissive License (UPL), Version 1.0
@@ -262,4 +262,16 @@ def test_unbound_local_variable(self):
             match (1, 3):
                 case (a, 1) | (a, 2):
                     pass
-            assert a == 1
+            assert a == 1
+
+    def test_missing_kwarg(self):
+        def f():
+            x = sum
+            match x:
+                case object(factor=x) if x is not None:
+                    pass
+
+        try:
+            f()
+        except AttributeError:
+            self.fail("Invalid keyword argument should not raise AttributeError")

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/bytecode/MatchClassNode.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * The Universal Permissive License (UPL), Version 1.0
@@ -139,7 +139,14 @@ Object match(VirtualFrame frame, Object subject, Object type, int nargs, @NeverD
             attrs = new Object[kwArgs.length];
         }
         // Finally, the keyword subpatterns:
-        getKwArgs(frame, inliningTarget, subject, type, kwArgs, seen, seenLength, attrs, attrsLength, getAttr, eqStrNode, raise);
+        try {
+            getKwArgs(frame, inliningTarget, subject, type, kwArgs, seen, seenLength, attrs, attrsLength, getAttr, eqStrNode, raise);
+        } catch (PException pe) {
+            // missing keyword argument will throw AttributeError, but in pattern matching, that
+            // should be ignored
+            pe.expectAttributeError(inliningTarget, isClassProfile);
+            return null;
+        }
         return PFactory.createList(language, attrs);
     }