5 files changed, 49 insertions, 24 deletions
diff --git a/Userland/Libraries/LibJS/CMakeLists.txt b/Userland/Libraries/LibJS/CMakeLists.txt
index 53c3ecd4b4..94bc6e2807 100644
--- a/Userland/Libraries/LibJS/CMakeLists.txt
+++ b/Userland/Libraries/LibJS/CMakeLists.txt
@@ -148,6 +148,7 @@ set(SOURCES
     Runtime/TypedArrayPrototype.cpp
     Runtime/Value.cpp
     Runtime/VM.cpp
+    Runtime/WeakContainer.cpp
     Runtime/WeakMap.cpp
     Runtime/WeakMapConstructor.cpp
     Runtime/WeakMapPrototype.cpp
diff --git a/Userland/Libraries/LibJS/Heap/Heap.cpp b/Userland/Libraries/LibJS/Heap/Heap.cpp
index 0c46359a2d..a233864ef7 100644
--- a/Userland/Libraries/LibJS/Heap/Heap.cpp
+++ b/Userland/Libraries/LibJS/Heap/Heap.cpp
@@ -226,8 +226,8 @@ void Heap::sweep_dead_cells(bool print_report, const Core::ElapsedTimer& measure
         allocator_for_size(block->cell_size()).block_did_become_usable({}, *block);
     }
 
-    for (auto* weak_container : m_weak_containers)
-        weak_container->remove_swept_cells({}, swept_cells);
+    for (auto& weak_container : m_weak_containers)
+        weak_container.remove_swept_cells({}, swept_cells);
 
     if constexpr (HEAP_DEBUG) {
         for_each_block([&](auto& block) {
@@ -282,14 +282,14 @@ void Heap::did_destroy_marked_value_list(Badge<MarkedValueList>, MarkedValueList
 
 void Heap::did_create_weak_container(Badge<WeakContainer>, WeakContainer& set)
 {
-    VERIFY(!m_weak_containers.contains(&set));
-    m_weak_containers.set(&set);
+    VERIFY(!m_weak_containers.contains(set));
+    m_weak_containers.append(set);
 }
 
 void Heap::did_destroy_weak_container(Badge<WeakContainer>, WeakContainer& set)
 {
-    VERIFY(m_weak_containers.contains(&set));
-    m_weak_containers.remove(&set);
+    VERIFY(m_weak_containers.contains(set));
+    m_weak_containers.remove(set);
 }
 
 void Heap::defer_gc(Badge<DeferGC>)
diff --git a/Userland/Libraries/LibJS/Heap/Heap.h b/Userland/Libraries/LibJS/Heap/Heap.h
index 4dbbc73a8c..0e3e4cbf9a 100644
--- a/Userland/Libraries/LibJS/Heap/Heap.h
+++ b/Userland/Libraries/LibJS/Heap/Heap.h
@@ -19,6 +19,7 @@
 #include <LibJS/Heap/CellAllocator.h>
 #include <LibJS/Heap/Handle.h>
 #include <LibJS/Runtime/Object.h>
+#include <LibJS/Runtime/WeakContainer.h>
 
 namespace JS {
 
@@ -111,7 +112,7 @@ private:
 
     MarkedValueList::List m_marked_value_lists;
 
-    HashTable<WeakContainer*> m_weak_containers;
+    WeakContainer::List m_weak_containers;
 
     BlockAllocator m_block_allocator;
 
diff --git a/Userland/Libraries/LibJS/Runtime/WeakContainer.cpp b/Userland/Libraries/LibJS/Runtime/WeakContainer.cpp
new file mode 100644
index 0000000000..387cbea5cc
--- /dev/null
+++ b/Userland/Libraries/LibJS/Runtime/WeakContainer.cpp
@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Heap/Heap.h>
+#include <LibJS/Runtime/WeakContainer.h>
+
+namespace JS {
+
+WeakContainer::WeakContainer(Heap& heap)
+    : m_heap(heap)
+{
+    m_heap.did_create_weak_container({}, *this);
+}
+
+WeakContainer::~WeakContainer()
+{
+    deregister();
+}
+
+void WeakContainer::deregister()
+{
+    if (!m_registered)
+        return;
+    m_heap.did_destroy_weak_container({}, *this);
+    m_registered = false;
+}
+
+}
diff --git a/Userland/Libraries/LibJS/Runtime/WeakContainer.h b/Userland/Libraries/LibJS/Runtime/WeakContainer.h
index fe49325fd1..4ac251279f 100644
--- a/Userland/Libraries/LibJS/Runtime/WeakContainer.h
+++ b/Userland/Libraries/LibJS/Runtime/WeakContainer.h
@@ -6,36 +6,28 @@
 
 #pragma once
 
-#include <LibJS/Heap/Heap.h>
+#include <AK/IntrusiveList.h>
 
 namespace JS {
 
 class WeakContainer {
 public:
-    explicit WeakContainer(Heap& heap)
-        : m_heap(heap)
-    {
-        m_heap.did_create_weak_container({}, *this);
-    }
-    virtual ~WeakContainer()
-    {
-        deregister();
-    }
+    explicit WeakContainer(Heap&);
+    virtual ~WeakContainer();
 
     virtual void remove_swept_cells(Badge<Heap>, Vector<Cell*>&) = 0;
 
 protected:
-    void deregister()
-    {
-        if (!m_registered)
-            return;
-        m_heap.did_destroy_weak_container({}, *this);
-        m_registered = false;
-    }
+    void deregister();
 
 private:
     bool m_registered { true };
     Heap& m_heap;
+
+    IntrusiveListNode<WeakContainer> m_list_node;
+
+public:
+    using List = IntrusiveList<WeakContainer, RawPtr<WeakContainer>, &WeakContainer::m_list_node>;
 };
 
 }