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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "nsISupports.h"
#include "nsISupportsImpl.h"
#include <mozilla/WeakPtr.h>
#include "nsCycleCollectionParticipant.h"
#include "nsWeakReference.h"
// --- Bad: Unlink does not call DetachWeakPtr ---
class BadClass : public nsISupports, // expected-error {{Cycle-collected class 'BadClass' inherits from 'SupportsWeakPtr' but its cycle collection Unlink does not call 'DetachWeakPtr'()}}
public mozilla::SupportsWeakPtr {
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(BadClass)
protected:
~BadClass() = default;
};
NS_IMPL_CYCLE_COLLECTING_ADDREF(BadClass)
NS_IMPL_CYCLE_COLLECTING_RELEASE(BadClass)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(BadClass)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_CLASS(BadClass)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(BadClass) // expected-note {{Unlink defined here; add 'NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_PTR'}}
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(BadClass)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
// --- Good: uses NS_IMPL_CYCLE_COLLECTION_WEAK_PTR ---
class GoodClass : public nsISupports,
public mozilla::SupportsWeakPtr {
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(GoodClass)
protected:
~GoodClass() = default;
};
NS_IMPL_CYCLE_COLLECTING_ADDREF(GoodClass)
NS_IMPL_CYCLE_COLLECTING_RELEASE(GoodClass)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(GoodClass)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_WEAK_PTR(GoodClass)
// --- Good: INHERITED variant where parent handles DetachWeakPtr ---
class ParentClass : public nsISupports,
public mozilla::SupportsWeakPtr {
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(ParentClass)
protected:
~ParentClass() = default;
};
NS_IMPL_CYCLE_COLLECTING_ADDREF(ParentClass)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ParentClass)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ParentClass)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_WEAK_PTR(ParentClass)
// ChildClass does not directly inherit SupportsWeakPtr — no warning.
class ChildClass : public ParentClass {
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ChildClass, ParentClass)
protected:
~ChildClass() = default;
};
NS_IMPL_ADDREF_INHERITED(ChildClass, ParentClass)
NS_IMPL_RELEASE_INHERITED(ChildClass, ParentClass)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ChildClass)
NS_INTERFACE_MAP_END_INHERITING(ParentClass)
NS_IMPL_CYCLE_COLLECTION_INHERITED(ChildClass, ParentClass)
// --- OK: SupportsWeakPtr with no cycle collection ---
class NotCycleCollected : public mozilla::SupportsWeakPtr {
};
// --- Bad: nsSupportsWeakReference Unlink does not call ClearWeakReferences ---
class BadWeakRefClass : public nsSupportsWeakReference { // expected-error {{Cycle-collected class 'BadWeakRefClass' inherits from 'nsSupportsWeakReference' but its cycle collection Unlink does not call 'ClearWeakReferences'()}}
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(BadWeakRefClass)
protected:
~BadWeakRefClass() = default;
};
NS_IMPL_CYCLE_COLLECTING_ADDREF(BadWeakRefClass)
NS_IMPL_CYCLE_COLLECTING_RELEASE(BadWeakRefClass)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(BadWeakRefClass)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_CLASS(BadWeakRefClass)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(BadWeakRefClass) // expected-note {{Unlink defined here; add 'NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE'}}
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(BadWeakRefClass)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
// --- Good: nsSupportsWeakReference with NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE ---
class GoodWeakRefClass : public nsSupportsWeakReference {
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(GoodWeakRefClass)
protected:
~GoodWeakRefClass() = default;
};
NS_IMPL_CYCLE_COLLECTING_ADDREF(GoodWeakRefClass)
NS_IMPL_CYCLE_COLLECTING_RELEASE(GoodWeakRefClass)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(GoodWeakRefClass)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_CLASS(GoodWeakRefClass)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(GoodWeakRefClass)
NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(GoodWeakRefClass)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END