Fix weakref.ref() with a callback accepting non-weakrefable objects

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

@@ -38,6 +38,16 @@
 # SOFTWARE.
 import weakref
 
+
+def assert_raises(err, fn, *args, **kwargs):
+    raised = False
+    try:
+        fn(*args, **kwargs)
+    except err:
+        raised = True
+    assert raised
+
+
 MAX_WAIT_COUNT = 500
 
 import sys
@@ -322,3 +332,58 @@ def __call__(self):
     proxy = weakref.proxy(a)
     assert callable(proxy) is True
     assert proxy() == 42
+
+
+def test_weakref_with_callback_object_type_support():
+    def callback(ref):
+        pass
+
+    assert_raises(TypeError, weakref.ref, {}, callback)
+    assert_raises(TypeError, weakref.proxy, {}, callback)
+    assert_raises(TypeError, weakref.ref, [1, 2], callback)
+    assert_raises(TypeError, weakref.proxy, [1, 2], callback)
+    assert_raises(TypeError, weakref.ref, 42, callback)
+    assert_raises(TypeError, weakref.proxy, 42, callback)
+    assert_raises(TypeError, weakref.ref, None, callback)
+    assert_raises(TypeError, weakref.proxy, None, callback)
+
+
+def test_weakref_builtin_types_with_weaklist():
+    import _queue, _struct, array, collections, contextvars, mmap, typing
+
+    def callback(ref):
+        pass
+
+    d = collections.deque()
+    assert weakref.ref(d)() is d
+    assert weakref.ref(d, callback)() is d
+    a = array.array('b')
+    assert weakref.ref(a)() is a
+    assert weakref.ref(a, callback)() is a
+    with mmap.mmap(-1, 1) as m:
+        assert weakref.ref(m)() is m
+        assert weakref.ref(m, callback)() is m
+    c = contextvars.copy_context()
+    assert weakref.ref(c)() is c
+    assert weakref.ref(c, callback)() is c
+    q = _queue.SimpleQueue()
+    assert weakref.ref(q)() is q
+    assert weakref.ref(q, callback)() is q
+    s = _struct.Struct('b')
+    assert weakref.ref(s)() is s
+    assert weakref.ref(s, callback)() is s
+    t = typing.TypeVar('T')
+    assert weakref.ref(t)() is t
+    assert weakref.ref(t, callback)() is t
+    ts = typing.TypeVarTuple('Ts')
+    assert weakref.ref(ts)() is ts
+    assert weakref.ref(ts, callback)() is ts
+    p = typing.ParamSpec('P')
+    assert weakref.ref(p)() is p
+    assert weakref.ref(p, callback)() is p
+    pa = p.args
+    assert weakref.ref(pa)() is pa
+    assert weakref.ref(pa, callback)() is pa
+    pk = p.kwargs
+    assert weakref.ref(pk)() is pk
+    assert weakref.ref(pk, callback)() is pk

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/modules/WeakRefModuleBuiltins.java

@@ -112,7 +112,8 @@ public static int getBuiltinTypeWeaklistoffset(PythonBuiltinClassType cls) {
                     -> 40;
             case PMethod, // method
                     PFileIO, // _io.FileIO
-                    PTee // itertools._tee
+                    PTee, // itertools._tee
+                    ContextVarsContext // _contextvars.Context
                     -> 32;
             case PFunction -> 80; // function
             case PIOBase, // _io._IOBase
@@ -122,9 +123,14 @@ public static int getBuiltinTypeWeaklistoffset(PythonBuiltinClassType cls) {
                     PLock // _thread.LockType
                     -> 24;
             case PBytesIO, // _io.BytesIO
-                    PPartial // functools.partial
+                    PPartial, // functools.partial
+                    PArray, // array.array
+                    PStruct // _struct.Struct
                     -> 48;
-            case PPattern -> 64; // _sre.Pattern
+            case PPattern, // _sre.Pattern
+                    PSimpleQueue // _queue.SimpleQueue
+                    -> 64;
+            case PMMap -> 72; // mmap.mmap
             case PStringIO -> 112; // _io.StringIO
             case PBufferedReader, // _io.BufferedReader
                     PBufferedWriter, // _io.BufferedWriter
@@ -134,6 +140,13 @@ public static int getBuiltinTypeWeaklistoffset(PythonBuiltinClassType cls) {
             case PickleBuffer -> 96; // _pickle.PickleBuffer
             case PTextIOWrapper -> 176; // _io.TextIOWrapper
             case POrderedDict -> 104;
+            case PDeque -> 208; // collections.deque
+            case PTypeVar, // typing.TypeVar
+                    PTypeVarTuple, // typing.TypeVarTuple
+                    PParamSpec, // typing.ParamSpec
+                    PParamSpecArgs, // typing.ParamSpecArgs
+                    PParamSpecKwargs // typing.ParamSpecKwargs
+                    -> -32;
             default -> 0;
             // @formatter:on
         };

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/referencetype/ReferenceTypeBuiltins.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 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
@@ -160,9 +160,13 @@ static PReferenceType refType(Object cls, Object object, @SuppressWarnings("unus
         @Specialization(guards = {"!isNativeObject(object)", "!isPNone(callback)"})
         static PReferenceType refTypeWithCallback(Object cls, Object object, Object callback,
                         @Bind Node inliningTarget,
+                        @Cached.Exclusive @Cached GetClassNode getClassNode,
                         @Cached.Exclusive @Cached HiddenAttr.ReadNode readQueueNode,
                         @Bind PythonLanguage language,
                         @Shared @Cached TypeNodes.GetInstanceShape getInstanceShape) {
+            if (getClassNode.execute(inliningTarget, object) instanceof PythonBuiltinClassType type && type.getWeaklistoffset() == 0) {
+                throw PRaiseNode.raiseStatic(inliningTarget, TypeError, ErrorMessages.CANNOT_CREATE_WEAK_REFERENCE_TO, object);
+            }
             return PFactory.createReferenceType(language, cls, getInstanceShape.execute(cls), object, callback, getWeakReferenceQueue(inliningTarget, readQueueNode));
         }