Updated memory management

src/rubicon/objc/api.py

@@ -100,13 +100,14 @@ def get_method_family(method_name: str) -> str:
     """Returns the method family from the method name. See
     https://clang.llvm.org/docs/AutomaticReferenceCounting.html#method-families for
     documentation on method families and corresponding selector names."""
-    method_name = method_name.lstrip("_").split(":")[0]
-    leading_lowercases = []
-    for c in method_name:
-        if c.isupper():
-            break
-        leading_lowercases.append(c)
-    return "".join(leading_lowercases)
+    first_component = method_name.lstrip("_").split(":")[0]
+    for family in _RETURNS_RETAINED_FAMILIES:
+        if first_component.startswith(family):
+            remainder = first_component.removeprefix(family)
+            if remainder == "" or remainder[0].isupper():
+                return family
+
+    return ""
 
 
 def method_name_to_tuple(name: str) -> (str, tuple[str, ...]):
@@ -254,9 +255,9 @@ def __call__(self, receiver, *args, convert_args=True, convert_result=True):
 
         # Init methods consume their `self` argument (the receiver), see
         # https://clang.llvm.org/docs/AutomaticReferenceCounting.html#semantics-of-init.
-        # To avoid segfaults on garbage collection if `init` does not return `self` but
-        # a different object or None, we issue an additional retain. This needs to be
-        # done before calling the method.
+        # To ensure the receiver pointer remains valid if `init` does not return `self`
+        # but a different object or None, we issue an additional retain. This needs to
+        # be done before calling the method.
         # Note that if `init` does return the same object, it will already be in our
         # cache and balanced with a `release` on cache retrieval.
         method_family = get_method_family(self.name.decode())
@@ -967,8 +968,12 @@ def __del__(self):
         # Autorelease our reference on garbage collection of the Python wrapper. We use
         # autorelease instead of release to allow ObjC to take ownership of an object when
         # it is returned from a factory method.
-        if send_message and objc_id:
+        try:
             send_message(self, "autorelease", restype=objc_id, argtypes=[])
+        except (NameError, TypeError):
+            # Handle interpreter shutdown gracefully where send_message might be deleted
+            # (NameError) or set to None (TypeError).
+            pass
 
     def __str__(self):
         """Get a human-readable representation of ``self``.

tests/test_core.py

@@ -1883,7 +1883,7 @@ def test_objcinstance_returned_lifecycle(self):
         # Check that the object is retained when we create the ObjCInstance.
         self.assertEqual(obj.retainCount(), 1, "object was not retained")
 
-        # Assign the object to an Obj-C weakref and delete it check that it is dealloced.
+        # Assign the object to an Obj-C weakref and delete it to check that it is dealloced.
         wr = ObjcWeakref.alloc().init()
         wr.weak_property = obj
 
@@ -1907,7 +1907,7 @@ def test_objcinstance_owned_lifecycle(self):
 
         self.assertEqual(obj.retainCount(), 1, "object should be retained only once")
 
-        # Assign the object to an Obj-C weakref and delete it check that it is dealloced.
+        # Assign the object to an Obj-C weakref and delete it to check that it is dealloced.
         wr = ObjcWeakref.alloc().init()
         wr.weak_property = obj
 
@@ -1933,7 +1933,7 @@ def test_objcinstance_immutable_copy_lifecycle(self):
         self.assertIs(obj0, obj1)
         self.assertIs(obj0, obj2)
 
-        # Assign the object to an Obj-C weakref and delete it check that it is dealloced.
+        # Assign the object to an Obj-C weakref and delete it to check that it is dealloced.
         wr = ObjcWeakref.alloc().init()
         wr.weak_property = obj0
 
@@ -1957,7 +1957,7 @@ def test_objcinstance_init_change_lifecycle(self):
 
         self.assertNotEqual(obj_allocated.ptr.value, obj_initialized.ptr.value)
 
-        # Assign the object to an Obj-C weakref and delete it check that it is dealloced.
+        # Assign the object to an Obj-C weakref and delete it to check that it is dealloced.
         wr = ObjcWeakref.alloc().init()
         wr.weak_property = obj_initialized
 
@@ -1972,8 +1972,31 @@ def test_objcinstance_init_change_lifecycle(self):
 
         self.assertIsNone(wr.weak_property, "object was not deallocated")
 
+    def test_objcinstance_alloc_lifecycle(self):
+        """We properly retain and release objects that are allocated but never
+        initialized."""
+        with autoreleasepool():
+            obj_allocated = NSObject.alloc()
+
+        self.assertEqual(obj_allocated.retainCount(), 1)
+
+        # Assign the object to an Obj-C weakref and delete it to check that it is dealloced.
+        wr = ObjcWeakref.alloc().init()
+        wr.weak_property = obj_allocated
+
+        with autoreleasepool():
+            del obj_allocated
+            gc.collect()
+
+            self.assertIsNotNone(
+                wr.weak_property,
+                "object was deallocated before end of autorelease pool",
+            )
+
+        self.assertIsNone(wr.weak_property, "object was not deallocated")
+
     def test_objcinstance_init_none(self):
-        """We do segfault if init returns a different object than it received in alloc."""
+        """We do not segfault if init returns nil."""
         with autoreleasepool():
             image = NSImage.alloc().initWithContentsOfFile("/no/file/here")
 
@@ -2186,7 +2209,9 @@ def work():
             thread.join()
 
     def test_get_method_family(self):
-        self.assertEqual(get_method_family("perform"), "perform")
-        self.assertEqual(get_method_family("performWith:"), "perform")
-        self.assertEqual(get_method_family("_performWith:"), "perform")
-        self.assertEqual(get_method_family("_perform:with:"), "perform")
+        self.assertEqual(get_method_family("mutableCopy"), "mutableCopy")
+        self.assertEqual(get_method_family("mutableCopy:"), "mutableCopy")
+        self.assertEqual(get_method_family("_mutableCopy:"), "mutableCopy")
+        self.assertEqual(get_method_family("_mutableCopy:with:"), "mutableCopy")
+        self.assertEqual(get_method_family("_mutableCopyWith:"), "mutableCopy")
+        self.assertEqual(get_method_family("_mutableCopying:"), "")