Implement WeakRef Object (#4546)

Related test262 test-cases has been removed from skip list.
Execpt two test-case since they need other feature to work (Finalization registry and async GC)

JerryScript-DCO-1.0-Signed-off-by: Bence Gabor Kis kisbg@inf.u-szeged.hu

docs/02.API-REFERENCE.md

@@ -57,6 +57,7 @@ Enum that contains JerryScript **object** value types:
  - JERRY_OBJECT_TYPE_SYMBOL - Symbol object
  - JERRY_OBJECT_TYPE_GENERATOR - Generator object
  - JERRY_OBJECT_TYPE_BIGINT - BigInt object
+ - JERRY_OBJECT_TYPE_WEAKREF - WeakRef object
 
 *New in version 2.4*.
 

jerry-core/CMakeLists.txt

@@ -220,6 +220,8 @@ set(SOURCE_CORE_FILES
   ecma/builtin-objects/ecma-builtin-urierror.c
   ecma/builtin-objects/ecma-builtin-weakmap-prototype.c
   ecma/builtin-objects/ecma-builtin-weakmap.c
+  ecma/builtin-objects/ecma-builtin-weakref-prototype.c
+  ecma/builtin-objects/ecma-builtin-weakref.c
   ecma/builtin-objects/ecma-builtin-weakset-prototype.c
   ecma/builtin-objects/ecma-builtin-weakset.c
   ecma/builtin-objects/ecma-builtins.c
@@ -408,6 +410,8 @@ if(ENABLE_AMALGAM)
     ecma/builtin-objects/ecma-builtin-urierror.inc.h
     ecma/builtin-objects/ecma-builtin-weakmap-prototype.inc.h
     ecma/builtin-objects/ecma-builtin-weakmap.inc.h
+    ecma/builtin-objects/ecma-builtin-weakref-prototype.inc.h
+    ecma/builtin-objects/ecma-builtin-weakref.inc.h
     ecma/builtin-objects/ecma-builtin-weakset-prototype.inc.h
     ecma/builtin-objects/ecma-builtin-weakset.inc.h
     ecma/builtin-objects/ecma-builtins-internal.h

jerry-core/api/jerry.c

@@ -1237,6 +1237,12 @@ jerry_object_get_type (const jerry_value_t value) /**< input value to check */
           return JERRY_OBJECT_TYPE_CONTAINER;
         }
 #endif /* JERRY_BUILTIN_CONTAINER */
+#if JERRY_BUILTIN_WEAKREF
+        case LIT_MAGIC_STRING_WEAKREF_UL:
+        {
+          return JERRY_OBJECT_TYPE_WEAKREF;
+        }
+#endif /* JERRY_BUILTIN_WEAKREF */
         default:
         {
           break;
@@ -1460,6 +1466,9 @@ jerry_is_feature_enabled (const jerry_feature_t feature) /**< feature to check *
 #if JERRY_BUILTIN_WEAKMAP
           || feature == JERRY_FEATURE_WEAKMAP
 #endif /* JERRY_BUILTIN_WEAKMAP */
+#if JERRY_BUILTIN_WEAKREF
+          || feature == JERRY_FEATURE_WEAKREF
+#endif /* JERRY_BUILTIN_WEAKREF */
 #if JERRY_BUILTIN_WEAKSET
           || feature == JERRY_FEATURE_WEAKSET
 #endif /* JERRY_BUILTIN_WEAKSET */

jerry-core/config.h

@@ -123,6 +123,10 @@
 # define JERRY_BUILTIN_WEAKMAP JERRY_ESNEXT
 #endif /* !defined (JERRY_BUILTIN_WEAKMAP) */
 
+#ifndef JERRY_BUILTIN_WEAKREF
+# define JERRY_BUILTIN_WEAKREF JERRY_ESNEXT
+#endif /* !defined (JERRY_BUILTIN_WEAKREF) */
+
 #ifndef JERRY_BUILTIN_WEAKSET
 # define JERRY_BUILTIN_WEAKSET JERRY_ESNEXT
 #endif /* !defined (JERRY_BUILTIN_WEAKSET) */
@@ -568,6 +572,10 @@
 || ((JERRY_BUILTIN_WEAKMAP != 0) && (JERRY_BUILTIN_WEAKMAP != 1))
 # error "Invalid value for JERRY_BUILTIN_WEAKMAP macro."
 #endif
+#if !defined (JERRY_BUILTIN_WEAKREF) \
+|| ((JERRY_BUILTIN_WEAKREF != 0) && (JERRY_BUILTIN_WEAKREF != 1))
+# error "Invalid value for JERRY_BUILTIN_WEAKREF macro."
+#endif
 #if !defined (JERRY_BUILTIN_WEAKSET) \
 || ((JERRY_BUILTIN_WEAKSET != 0) && (JERRY_BUILTIN_WEAKSET != 1))
 # error "Invalid value for JERRY_BUILTIN_WEAKSET macro."
@@ -597,6 +605,7 @@
 || (JERRY_BUILTIN_MAP == 1) \
 || (JERRY_BUILTIN_SET == 1) \
 || (JERRY_BUILTIN_WEAKMAP == 1) \
+|| (JERRY_BUILTIN_WEAKREF == 1) \
 || (JERRY_BUILTIN_WEAKSET == 1) \
 || (JERRY_BUILTIN_PROMISE == 1) \
 || (JERRY_BUILTIN_PROXY == 1) \

jerry-core/ecma/base/ecma-gc.c

@@ -1382,7 +1382,7 @@ ecma_gc_free_properties (ecma_object_t *object_p) /**< object */
           break;
         }
 #endif /* JERRY_ESNEXT */
-#if JERRY_BUILTIN_WEAKMAP || JERRY_BUILTIN_WEAKSET
+#if JERRY_BUILTIN_WEAKMAP || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKREF
         case LIT_INTERNAL_MAGIC_STRING_WEAK_REFS:
         {
           ecma_collection_t *refs_p = ECMA_GET_INTERNAL_VALUE_POINTER (ecma_collection_t,
@@ -1392,17 +1392,23 @@ ecma_gc_free_properties (ecma_object_t *object_p) /**< object */
             const ecma_value_t value = refs_p->buffer_p[j];
             if (!ecma_is_value_empty (value))
             {
-              ecma_object_t *container_p = ecma_get_object_from_value (value);
+              ecma_object_t *obj_p = ecma_get_object_from_value (value);
 
-              ecma_op_container_remove_weak_entry (container_p,
-                                                   ecma_make_object_value (object_p));
+              if (ecma_object_class_is (obj_p, LIT_MAGIC_STRING_WEAKREF_UL))
+              {
+                JERRY_ASSERT (ecma_object_class_is (obj_p, LIT_MAGIC_STRING_WEAKREF_UL));
+                ecma_extended_object_t *ext_obj_p = (ecma_extended_object_t *) obj_p;
+                ext_obj_p->u.class_prop.u.target = ECMA_VALUE_UNDEFINED;
+                continue;
+              }
+              ecma_op_container_remove_weak_entry (obj_p, ecma_make_object_value (object_p));
             }
           }
 
           ecma_collection_destroy (refs_p);
           break;
         }
-#endif /* JERRY_BUILTIN_WEAKMAP || JERRY_BUILTIN_WEAKSET */
+#endif /* JERRY_BUILTIN_WEAKMAP || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKREF */
         default:
         {
           JERRY_ASSERT (name_cp == LIT_INTERNAL_MAGIC_STRING_NATIVE_POINTER);
@@ -1641,6 +1647,18 @@ ecma_gc_free_object (ecma_object_t *object_p) /**< object to free */
           break;
         }
 #endif /* JERRY_BUILTIN_PROMISE */
+#if JERRY_BUILTIN_WEAKREF
+        case LIT_MAGIC_STRING_WEAKREF_UL:
+        {
+          ecma_value_t target = ext_object_p->u.class_prop.u.target;
+
+          if (!ecma_is_value_undefined (target))
+          {
+            ecma_op_object_unref_weak (ecma_get_object_from_value (target), ecma_make_object_value (object_p));
+          }
+          break;
+        }
+#endif /* JERRY_BUILTIN_WEAKREF */
 #if JERRY_BUILTIN_CONTAINER
 #if JERRY_BUILTIN_MAP
         case LIT_MAGIC_STRING_MAP_UL:

jerry-core/ecma/base/ecma-globals.h

@@ -959,7 +959,7 @@ typedef struct
         ecma_value_t date; /**< Date object [[DateValue]] internal property */
         int32_t tza; /**< TimeZone adjustment for date objects */
         uint32_t length; /**< length related property (e.g. length of ArrayBuffer) */
-        ecma_value_t target; /**< [[ProxyTarget]] internal property */
+        ecma_value_t target; /**< [[ProxyTarget]] or [[WeakRefTarget]] internal property */
         ecma_value_t head; /**< points to the async generator task queue head item */
         ecma_value_t promise; /**< PromiseCapability[[Promise]] internal slot */
       } u;

jerry-core/ecma/builtin-objects/ecma-builtin-global.inc.h

@@ -233,14 +233,20 @@ OBJECT_VALUE (LIT_MAGIC_STRING_SET_UL,
 OBJECT_VALUE (LIT_MAGIC_STRING_WEAKMAP_UL,
               ECMA_BUILTIN_ID_WEAKMAP,
               ECMA_PROPERTY_CONFIGURABLE_WRITABLE)
-#endif /* JERRY_BUILTIN_SET */
+#endif /* JERRY_BUILTIN_WEAKMAP */
+
+#if JERRY_BUILTIN_WEAKREF
+OBJECT_VALUE (LIT_MAGIC_STRING_WEAKREF_UL,
+              ECMA_BUILTIN_ID_WEAKREF,
+              ECMA_PROPERTY_CONFIGURABLE_WRITABLE)
+#endif /* JERRY_BUILTIN_WEAKREF */
 
 #if JERRY_BUILTIN_WEAKSET
 /* ECMA-262 v6, 23.1.1.1 */
 OBJECT_VALUE (LIT_MAGIC_STRING_WEAKSET_UL,
               ECMA_BUILTIN_ID_WEAKSET,
               ECMA_PROPERTY_CONFIGURABLE_WRITABLE)
-#endif /* JERRY_BUILTIN_SET */
+#endif /* JERRY_BUILTIN_WEAKSET */
 
 #if JERRY_ESNEXT
 /* ECMA-262 v6, 19.4.1.1 */

jerry-core/ecma/builtin-objects/ecma-builtin-weakref-prototype.c

@@ -0,0 +1,72 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "ecma-container-object.h"
+#include "ecma-exceptions.h"
+
+#if JERRY_BUILTIN_WEAKREF
+
+#define ECMA_BUILTINS_INTERNAL
+#include "ecma-builtins-internal.h"
+
+/**
+ * This object has a custom dispatch function.
+ */
+#define BUILTIN_INC_HEADER_NAME "ecma-builtin-weakref-prototype.inc.h"
+#define BUILTIN_UNDERSCORED_ID weakref_prototype
+#include "ecma-builtin-internal-routines-template.inc.h"
+
+/** \addtogroup ecma ECMA
+ * @{
+ *
+ * \addtogroup ecmabuiltins
+ * @{
+ *
+ * \addtogroup weakref ECMA WeakRef object built-in
+ * @{
+ */
+
+ /**
+  * Deref checks weakRef target
+  *
+  * @return weakRef target
+  *         error - otherwise
+  */
+static ecma_value_t
+ecma_builtin_weakref_prototype_object_deref (ecma_value_t this_arg) /**< this argument */
+{
+  if (!ecma_is_value_object (this_arg))
+  {
+    return ecma_raise_type_error ("Target is not Object");
+  }
+
+  ecma_object_t *object_p = ecma_get_object_from_value (this_arg);
+  ecma_extended_object_t *this_ext_obj = (ecma_extended_object_t *) object_p;
+
+  if (!ecma_object_class_is (object_p, LIT_MAGIC_STRING_WEAKREF_UL))
+  {
+    return ecma_raise_type_error ("Target is not weakRef");
+  }
+
+  return ecma_copy_value (this_ext_obj->u.class_prop.u.target);
+} /* ecma_builtin_weakref_prototype_object_deref */
+
+/**
+ * @}
+ * @}
+ * @}
+ */
+
+#endif /* JERRY_BUILTIN_WEAKREF */

jerry-core/ecma/builtin-objects/ecma-builtin-weakref-prototype.inc.h

@@ -0,0 +1,41 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * WeakSet.prototype built-in description
+ */
+
+#include "ecma-builtin-helpers-macro-defines.inc.h"
+
+#if JERRY_BUILTIN_WEAKREF
+
+/* Object properties:
+ *  (property name, object pointer getter) */
+
+OBJECT_VALUE (LIT_MAGIC_STRING_CONSTRUCTOR,
+              ECMA_BUILTIN_ID_WEAKREF,
+              ECMA_PROPERTY_CONFIGURABLE_WRITABLE)
+
+STRING_VALUE (LIT_GLOBAL_SYMBOL_TO_STRING_TAG,
+              LIT_MAGIC_STRING_WEAKREF_UL,
+              ECMA_PROPERTY_FLAG_CONFIGURABLE)
+
+/* Routine properties:
+ *  (property name, C routine name, arguments number or NON_FIXED, value of the routine's length property) */
+ROUTINE (LIT_MAGIC_STRING_DEREF, ecma_builtin_weakref_prototype_object_deref, 0, 0)
+
+#endif /* JERRY_BUILTIN_WEAKREF */
+
+#include "ecma-builtin-helpers-macro-undefs.inc.h"

jerry-core/ecma/builtin-objects/ecma-builtin-weakref.c

@@ -0,0 +1,97 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "ecma-builtins.h"
+#include "ecma-exceptions.h"
+#include "jcontext.h"
+#include "ecma-function-object.h"
+#include "ecma-gc.h"
+
+#if JERRY_BUILTIN_WEAKREF
+
+#define ECMA_BUILTINS_INTERNAL
+#include "ecma-builtins-internal.h"
+
+#define BUILTIN_INC_HEADER_NAME "ecma-builtin-weakref.inc.h"
+#define BUILTIN_UNDERSCORED_ID weakref
+#include "ecma-builtin-internal-routines-template.inc.h"
+
+/** \addtogroup ecma ECMA
+ * @{
+ *
+ * \addtogroup ecmabuiltins
+ * @{
+ *
+ * \addtogroup weakref ECMA WeakRef object built-in
+ * @{
+ */
+
+/**
+ * Handle calling [[Call]] of built-in WeakRef object
+ *
+ * @return ecma value
+ */
+ecma_value_t
+ecma_builtin_weakref_dispatch_call (const ecma_value_t *arguments_list_p, /**< arguments list */
+                                    uint32_t arguments_list_len) /**< number of arguments */
+{
+  JERRY_ASSERT (arguments_list_len == 0 || arguments_list_p != NULL);
+
+  return ecma_raise_type_error (ECMA_ERR_MSG ("Constructor WeakRef requires 'new'."));
+} /* ecma_builtin_weakref_dispatch_call */
+
+/**
+ * Handle calling [[Construct]] of built-in WeakRef object
+ *
+ * @return ecma value
+ */
+ecma_value_t
+ecma_builtin_weakref_dispatch_construct (const ecma_value_t *arguments_list_p, /**< arguments list */
+                                         uint32_t arguments_list_len) /**< number of arguments */
+{
+  if (arguments_list_len == 0 || !ecma_is_value_object (arguments_list_p[0]))
+  {
+    return ecma_raise_type_error (ECMA_ERR_MSG ("WeakRef target must be an object"));
+  }
+
+  JERRY_ASSERT (JERRY_CONTEXT (current_new_target_p) != NULL);
+
+  ecma_object_t *proto_p = ecma_op_get_prototype_from_constructor (JERRY_CONTEXT (current_new_target_p),
+                                                                   ECMA_BUILTIN_ID_WEAKREF_PROTOTYPE);
+
+  if (JERRY_UNLIKELY (proto_p == NULL))
+  {
+    return ECMA_VALUE_ERROR;
+  }
+
+  ecma_object_t *object_p  = ecma_create_object (proto_p,
+                                                 sizeof (ecma_extended_object_t),
+                                                 ECMA_OBJECT_TYPE_CLASS);
+  ecma_deref_object (proto_p);
+  ecma_extended_object_t *ext_obj_p = (ecma_extended_object_t *) object_p;
+  ext_obj_p->u.class_prop.class_id = (uint16_t) LIT_MAGIC_STRING_WEAKREF_UL;
+  ext_obj_p->u.class_prop.u.target = arguments_list_p[0];
+  ecma_op_object_set_weak (ecma_get_object_from_value (arguments_list_p[0]), object_p);
+
+  return ecma_make_object_value (object_p);
+} /* ecma_builtin_weakref_dispatch_construct */
+
+/**
+ * @}
+ * @}
+ * @}
+ */
+
+#endif /* JERRY_BUILTIN_WEAKREF */

jerry-core/ecma/builtin-objects/ecma-builtin-weakref.inc.h

@@ -0,0 +1,44 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * WeakRef built-in description
+ */
+
+#include "ecma-builtin-helpers-macro-defines.inc.h"
+
+#if JERRY_BUILTIN_WEAKREF
+
+/* Number properties:
+ *  (property name, number value, writable, enumerable, configurable) */
+
+NUMBER_VALUE (LIT_MAGIC_STRING_LENGTH,
+              1,
+              ECMA_PROPERTY_FLAG_CONFIGURABLE)
+
+STRING_VALUE (LIT_MAGIC_STRING_NAME,
+              LIT_MAGIC_STRING_WEAKREF_UL,
+              ECMA_PROPERTY_FLAG_CONFIGURABLE)
+
+/* Object properties:
+ *  (property name, object pointer getter) */
+
+OBJECT_VALUE (LIT_MAGIC_STRING_PROTOTYPE,
+              ECMA_BUILTIN_ID_WEAKREF_PROTOTYPE,
+              ECMA_PROPERTY_FIXED)
+
+#endif /* JERRY_BUILTIN_WEAKREF */
+
+#include "ecma-builtin-helpers-macro-undefs.inc.h"

jerry-core/ecma/builtin-objects/ecma-builtins.inc.h

@@ -565,7 +565,25 @@ BUILTIN_ROUTINE (ECMA_BUILTIN_ID_WEAKSET,
 
 #endif /* JERRY_BUILTIN_WEAKSET */
 
-#if JERRY_BUILTIN_PROXY
+#if JERRY_BUILTIN_WEAKREF
+
+/* The WeakRef prototype object */
+BUILTIN (ECMA_BUILTIN_ID_WEAKREF_PROTOTYPE,
+         ECMA_OBJECT_TYPE_GENERAL,
+         ECMA_BUILTIN_ID_OBJECT_PROTOTYPE,
+         true,
+         weakref_prototype)
+
+/* The WeakRef routine */
+BUILTIN_ROUTINE (ECMA_BUILTIN_ID_WEAKREF,
+                 ECMA_OBJECT_TYPE_NATIVE_FUNCTION,
+                 ECMA_BUILTIN_ID_FUNCTION_PROTOTYPE,
+                 true,
+                 weakref)
+
+#endif /* JERRY_BUILTIN_WEAKREF */
+
+#if (JERRY_BUILTIN_PROXY)
 /* The Proxy routine (ECMA-262 v6, 26.2.1) */
 BUILTIN_ROUTINE (ECMA_BUILTIN_ID_PROXY,
                  ECMA_OBJECT_TYPE_NATIVE_FUNCTION,

jerry-core/ecma/operations/ecma-container-object.c

@@ -207,7 +207,7 @@ ecma_op_container_free_weakset_entries (ecma_object_t *object_p, /**< object poi
       continue;
     }
 
-    ecma_op_container_unref_weak (ecma_get_object_from_value (*entry_p), ecma_make_object_value (object_p));
+    ecma_op_object_unref_weak (ecma_get_object_from_value (*entry_p), ecma_make_object_value (object_p));
     ecma_op_container_remove_weak_entry (object_p, *entry_p);
 
     *entry_p = ECMA_VALUE_EMPTY;
@@ -238,7 +238,7 @@ ecma_op_container_free_weakmap_entries (ecma_object_t *object_p, /**< object poi
       continue;
     }
 
-    ecma_op_container_unref_weak (ecma_get_object_from_value (entry_p->key), ecma_make_object_value (object_p));
+    ecma_op_object_unref_weak (ecma_get_object_from_value (entry_p->key), ecma_make_object_value (object_p));
     ecma_op_container_remove_weak_entry (object_p, entry_p->key);
 
     ecma_free_value_if_not_object (entry_p->value);
@@ -666,48 +666,6 @@ ecma_op_container_has (ecma_extended_object_t *map_object_p, /**< map object */
   return ecma_make_boolean_value (entry_p != NULL);
 } /* ecma_op_container_has */
 
-/**
- * Set a weak reference from a container to a key object
- */
-static void
-ecma_op_container_set_weak (ecma_object_t *const key_p, /**< key object */
-                            ecma_extended_object_t *const container_p) /**< container */
-{
-  if (JERRY_UNLIKELY (ecma_op_object_is_fast_array (key_p)))
-  {
-    ecma_fast_array_convert_to_normal (key_p);
-  }
-
-  ecma_string_t *weak_refs_string_p = ecma_get_internal_string (LIT_INTERNAL_MAGIC_STRING_WEAK_REFS);
-  ecma_property_t *property_p = ecma_find_named_property (key_p, weak_refs_string_p);
-  ecma_collection_t *refs_p;
-
-  if (property_p == NULL)
-  {
-    ecma_property_value_t *value_p;
-    ECMA_CREATE_INTERNAL_PROPERTY (key_p, weak_refs_string_p, property_p, value_p);
-
-    refs_p = ecma_new_collection ();
-    ECMA_SET_INTERNAL_VALUE_POINTER (value_p->value, refs_p);
-  }
-  else
-  {
-    refs_p = ECMA_GET_INTERNAL_VALUE_POINTER (ecma_collection_t, (ECMA_PROPERTY_VALUE_PTR (property_p)->value));
-  }
-
-  const ecma_value_t container_value = ecma_make_object_value ((ecma_object_t *) container_p);
-  for (uint32_t i = 0; i < refs_p->item_count; i++)
-  {
-    if (ecma_is_value_empty (refs_p->buffer_p[i]))
-    {
-      refs_p->buffer_p[i] = container_value;
-      return;
-    }
-  }
-
-  ecma_collection_push_back (refs_p, container_value);
-} /* ecma_op_container_set_weak */
-
 /**
  * Helper method for the Map.prototype.set and Set.prototype.add methods to swap the sign of the given value if needed
  *
@@ -769,7 +727,7 @@ ecma_op_container_set (ecma_extended_object_t *map_object_p, /**< map object */
     if ((map_object_p->u.class_prop.extra_info & ECMA_CONTAINER_FLAGS_WEAK) != 0)
     {
       ecma_object_t *key_p = ecma_get_object_from_value (key_arg);
-      ecma_op_container_set_weak (key_p, map_object_p);
+      ecma_op_object_set_weak (key_p, (ecma_object_t *) map_object_p);
     }
 #endif /* JERRY_BUILTIN_WEAKMAP ||  JERRY_BUILTIN_WEAKSET */
   }
@@ -906,38 +864,11 @@ ecma_op_container_delete_weak (ecma_extended_object_t *map_object_p, /**< map ob
   ecma_op_internal_buffer_delete (container_p, (ecma_container_pair_t *) entry_p, lit_id);
 
   ecma_object_t *key_object_p = ecma_get_object_from_value (key_arg);
-  ecma_op_container_unref_weak (key_object_p, ecma_make_object_value ((ecma_object_t *) map_object_p));
+  ecma_op_object_unref_weak (key_object_p, ecma_make_object_value ((ecma_object_t *) map_object_p));
 
   return ECMA_VALUE_TRUE;
 } /* ecma_op_container_delete_weak */
 
-/**
- * Helper function to remove a weak reference to an object.
- *
- * @return ecma value
- *         Returned value must be freed with ecma_free_value.
- */
-void
-ecma_op_container_unref_weak (ecma_object_t *object_p, /**< this argument */
-                              ecma_value_t ref_holder) /**< key argument */
-{
-  ecma_string_t *weak_refs_string_p = ecma_get_internal_string (LIT_INTERNAL_MAGIC_STRING_WEAK_REFS);
-
-  ecma_property_t *property_p = ecma_find_named_property (object_p, weak_refs_string_p);
-  JERRY_ASSERT (property_p != NULL);
-
-  ecma_collection_t *refs_p = ECMA_GET_INTERNAL_VALUE_POINTER (ecma_collection_t,
-                                                               ECMA_PROPERTY_VALUE_PTR (property_p)->value);
-  for (uint32_t i = 0; i < refs_p->item_count; i++)
-  {
-    if (refs_p->buffer_p[i] == ref_holder)
-    {
-      refs_p->buffer_p[i] = ECMA_VALUE_EMPTY;
-      break;
-    }
-  }
-} /* ecma_op_container_unref_weak */
-
 /**
  * Helper function to remove a key/value pair from a weak container object
  */

jerry-core/ecma/operations/ecma-container-object.h

@@ -67,7 +67,6 @@ ecma_value_t ecma_op_container_delete (ecma_extended_object_t *map_object_p, ecm
                                        lit_magic_string_id_t lit_id);
 ecma_value_t ecma_op_container_delete_weak (ecma_extended_object_t *map_object_p, ecma_value_t key_arg,
                                             lit_magic_string_id_t lit_id);
-void ecma_op_container_unref_weak (ecma_object_t *object_p, ecma_value_t ref_holder);
 void ecma_op_container_remove_weak_entry (ecma_object_t *container_p, ecma_value_t key_arg);
 void ecma_op_container_free_entries (ecma_object_t *object_p);
 ecma_value_t ecma_op_container_create_iterator (ecma_value_t this_arg,

jerry-core/ecma/operations/ecma-objects.c

@@ -2650,6 +2650,9 @@ ecma_object_check_class_name_is_object (ecma_object_t *obj_p) /**< object */
 #if JERRY_BUILTIN_WEAKMAP
           || ecma_builtin_is (obj_p, ECMA_BUILTIN_ID_WEAKMAP_PROTOTYPE)
 #endif /* JERRY_BUILTIN_WEAKMAP */
+#if JERRY_BUILTIN_WEAKREF
+          || ecma_builtin_is (obj_p, ECMA_BUILTIN_ID_WEAKREF_PROTOTYPE)
+#endif /* JERRY_BUILTIN_WEAKREF */
 #if JERRY_BUILTIN_WEAKSET
           || ecma_builtin_is (obj_p, ECMA_BUILTIN_ID_WEAKSET_PROTOTYPE)
 #endif /* JERRY_BUILTIN_WEAKSET */
@@ -3239,6 +3242,82 @@ ecma_op_ordinary_object_has_own_property (ecma_object_t *object_p, /**< the obje
   return property != ECMA_PROPERTY_TYPE_NOT_FOUND && property != ECMA_PROPERTY_TYPE_NOT_FOUND_AND_STOP;
 } /* ecma_op_ordinary_object_has_own_property */
 
+#if JERRY_BUILTIN_WEAKREF || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKMAP
+
+/**
+ * Set a weak reference from a container or WeakRefObject to a key object
+ */
+void
+ecma_op_object_set_weak (ecma_object_t *object_p, /**< key object */
+                         ecma_object_t *target_p) /**< target object */
+{
+  if (JERRY_UNLIKELY (ecma_op_object_is_fast_array (object_p)))
+  {
+    ecma_fast_array_convert_to_normal (object_p);
+  }
+
+  ecma_string_t *weak_refs_string_p = ecma_get_internal_string (LIT_INTERNAL_MAGIC_STRING_WEAK_REFS);
+  ecma_property_t *property_p = ecma_find_named_property (object_p, weak_refs_string_p);
+  ecma_collection_t *refs_p;
+
+  if (property_p == NULL)
+  {
+    ecma_property_value_t *value_p;
+    ECMA_CREATE_INTERNAL_PROPERTY (object_p, weak_refs_string_p, property_p, value_p);
+
+    refs_p = ecma_new_collection ();
+    ECMA_SET_INTERNAL_VALUE_POINTER (value_p->value, refs_p);
+  }
+  else
+  {
+    refs_p = ECMA_GET_INTERNAL_VALUE_POINTER (ecma_collection_t, (ECMA_PROPERTY_VALUE_PTR (property_p)->value));
+  }
+
+  const ecma_value_t target_value = ecma_make_object_value ((ecma_object_t *) target_p);
+  for (uint32_t i = 0; i < refs_p->item_count; i++)
+  {
+    if (ecma_is_value_empty (refs_p->buffer_p[i]))
+    {
+      refs_p->buffer_p[i] = target_value;
+      return;
+    }
+  }
+
+  ecma_collection_push_back (refs_p, target_value);
+} /* ecma_op_object_set_weak */
+
+/**
+ * Helper function to remove a weak reference to an object.
+ *
+ * @return ecma value
+ *         Returned value must be freed with ecma_free_value.
+ */
+void
+ecma_op_object_unref_weak (ecma_object_t *object_p, /**< this argument */
+                           ecma_value_t ref_holder) /**< key argument */
+{
+  ecma_string_t *weak_refs_string_p = ecma_get_internal_string (LIT_INTERNAL_MAGIC_STRING_WEAK_REFS);
+
+  ecma_property_t *property_p = ecma_find_named_property (object_p, weak_refs_string_p);
+  JERRY_ASSERT (property_p != NULL);
+
+  ecma_collection_t *refs_p = ECMA_GET_INTERNAL_VALUE_POINTER (ecma_collection_t,
+                                                               ECMA_PROPERTY_VALUE_PTR (property_p)->value);
+  ecma_value_t *buffer_p = refs_p->buffer_p;
+
+  while (true)
+  {
+    if (*buffer_p == ref_holder)
+    {
+      *buffer_p = ECMA_VALUE_EMPTY;
+      return;
+    }
+    JERRY_ASSERT (buffer_p < refs_p->buffer_p + refs_p->item_count);
+    buffer_p++;
+  }
+} /* ecma_op_object_unref_weak */
+
+#endif /* JERRY_BUILTIN_WEAKREF || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKMAP */
 /**
  * Raise property redefinition error
  *

jerry-core/ecma/operations/ecma-objects.h

@@ -109,6 +109,10 @@ ecma_value_t ecma_op_species_constructor (ecma_object_t *this_value, ecma_builti
 ecma_value_t ecma_op_invoke_by_symbol_id (ecma_value_t object, lit_magic_string_id_t magic_string_id,
                                           ecma_value_t *args_p, uint32_t args_len);
 #endif /* JERRY_ESNEXT */
+#if JERRY_BUILTIN_WEAKREF || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKMAP
+void ecma_op_object_set_weak (ecma_object_t *object_p, ecma_object_t *target_p);
+void ecma_op_object_unref_weak (ecma_object_t *object_p, ecma_value_t ref_holder);
+#endif /* JERRY_BUILTIN_WEAKREF || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKMAP */
 ecma_value_t ecma_op_invoke (ecma_value_t object, ecma_string_t *property_name_p, ecma_value_t *args_p,
                              uint32_t args_len);
 ecma_value_t ecma_op_invoke_by_magic_id (ecma_value_t object, lit_magic_string_id_t magic_string_id,

jerry-core/include/jerryscript-core.h

@@ -109,6 +109,7 @@ typedef enum
   JERRY_FEATURE_GLOBAL_THIS, /**< GlobalThisValue support */
   JERRY_FEATURE_PROMISE_CALLBACK, /**< Promise callback support */
   JERRY_FEATURE_MODULE, /**< Module support */
+  JERRY_FEATURE_WEAKREF, /**< WeakRef support */
   JERRY_FEATURE__COUNT /**< number of features. NOTE: must be at the end of the list */
 } jerry_feature_t;
 
@@ -491,6 +492,7 @@ typedef enum
   JERRY_OBJECT_TYPE_SYMBOL,       /**< Symbol object */
   JERRY_OBJECT_TYPE_GENERATOR,    /**< Generator object */
   JERRY_OBJECT_TYPE_BIGINT,       /**< BigInt object */
+  JERRY_OBJECT_TYPE_WEAKREF,       /**< WeakRef object */
 } jerry_object_type_t;
 
 /**

jerry-core/lit/lit-magic-strings.h

@@ -67,6 +67,7 @@ typedef enum
                                                                                     *   data properties */
   LIT_INTERNAL_MAGIC_STRING_ENVIRONMENT_RECORD, /**< dynamic environment record needed by class constructors */
   LIT_INTERNAL_MAGIC_STRING_CLASS_FIELD_COMPUTED, /**< computed class field name list */
+  LIT_INTERNAL_MAGIC_STRING_CONTAINER_WEAK_REFS, /**< Weak references to the current container object */
   LIT_INTERNAL_MAGIC_STRING_WEAK_REFS, /**< Weak references to the current object */
   LIT_MAGIC_STRING__COUNT /**< number of magic strings */
 } lit_magic_string_id_t;

jerry-core/lit/lit-magic-strings.inc.h

@@ -248,6 +248,9 @@ LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_CLEAR, "clear")
 #if JERRY_BUILTIN_MATH && JERRY_ESNEXT
 LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_CLZ32, "clz32")
 #endif
+#if JERRY_BUILTIN_WEAKREF
+LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_DEREF, "deref")
+#endif
 #if JERRY_BUILTIN_ARRAY \
 || JERRY_BUILTIN_TYPEDARRAY
 LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_EVERY, "every")
@@ -457,6 +460,10 @@ LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_SYMBOL_DOT_UL, "Symbol.")
 || JERRY_BUILTIN_WEAKMAP
 LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_WEAKMAP_UL, "WeakMap")
 #endif
+#if JERRY_BUILTIN_WEAKMAP || JERRY_BUILTIN_WEAKSET || JERRY_BUILTIN_WEAKREF \
+|| JERRY_BUILTIN_WEAKREF
+LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_WEAKREF_UL, "WeakRef")
+#endif
 #if JERRY_BUILTIN_CONTAINER \
 || JERRY_BUILTIN_WEAKSET
 LIT_MAGIC_STRING_DEF (LIT_MAGIC_STRING_WEAKSET_UL, "WeakSet")

jerry-core/lit/lit-magic-strings.ini

@@ -111,6 +111,7 @@ LIT_MAGIC_STRING_ATANH = "atanh"
 LIT_MAGIC_STRING_CATCH = "catch"
 LIT_MAGIC_STRING_CLEAR = "clear"
 LIT_MAGIC_STRING_CLZ32 = "clz32"
+LIT_MAGIC_STRING_DEREF = "deref"
 LIT_MAGIC_STRING_EVERY = "every"
 LIT_MAGIC_STRING_EXPM1 = "expm1"
 LIT_MAGIC_STRING_FALSE = "false"
@@ -215,6 +216,7 @@ LIT_MAGIC_STRING_UNICODE = "unicode"
 LIT_MAGIC_STRING_UNSHIFT = "unshift"
 LIT_MAGIC_STRING_VALUE_OF_UL = "valueOf"
 LIT_MAGIC_STRING_WEAKMAP_UL = "WeakMap"
+LIT_MAGIC_STRING_WEAKREF_UL = "WeakRef"
 LIT_MAGIC_STRING_WEAKSET_UL = "WeakSet"
 LIT_MAGIC_STRING_EPSILON_U = "EPSILON"
 LIT_MAGIC_STRING_DATAVIEW_UL = "DataView"

jerry-core/profiles/README.md

@@ -122,6 +122,8 @@ defined to `1`.
   Enables or disables the [WeakMap](https://262.ecma-international.org/11.0/#sec-weakmap-objects) built-in.
 * `JERRY_BUILTIN_WEAKSET`:
   Enables or disables the [WeakSet](https://262.ecma-international.org/11.0/#sec-weakmap-objects) built-in.
+* `JERRY_BUILTIN_WEAKREF`:
+  Enables or disables the [WeakRef](https://tc39.es/ecma262/#sec-weak-ref-constructor) built-in.
 * `JERRY_MODULE_SYSTEM`:
   Enables or disable the [module system](http://www.ecma-international.org/ecma-262/6.0/#sec-modules) language element.
 * `JERRY_ESNEXT`: Enables or disables all of the implemented [ECMAScript2015+ features](http://www.ecma-international.org/ecma-262/10.0/) above.

tests/jerry/es.next/weakref.js

@@ -0,0 +1,69 @@
+// Copyright JS Foundation and other contributors, http://js.foundation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+var target_obj = {};
+var not_target_obj = {};
+var weak_ref = new WeakRef(target_obj);
+var weak_ref2 = new WeakRef(target_obj);
+
+assert (weak_ref.deref() === target_obj);
+assert (weak_ref.deref() === weak_ref2.deref());
+assert (weak_ref.deref() !== not_target_obj);
+
+assert (weak_ref2.deref() === target_obj);
+assert (weak_ref2.deref() !== not_target_obj);
+assert (weak_ref2.deref() === weak_ref2.deref());
+
+target_obj = undefined;
+gc();
+
+assert (weak_ref.deref() === undefined);
+assert (weak_ref2.deref() === undefined);
+
+var key_obj_1 = {};
+var key_obj_2 = {};
+var key_obj_3 = {};
+var target_obj_2 = {};
+var target_obj_3 = {};
+var weak_ref_3 = new WeakRef(key_obj_1);
+var weak_ref_4 = new WeakRef(target_obj_2);
+var weak_ref_5 = new WeakRef(target_obj_3);
+
+var weak_map = new WeakMap();
+weak_map.set(key_obj_1, weak_ref_3);
+weak_map.set(key_obj_2, weak_ref_4);
+weak_map.set(key_obj_3, weak_ref_5);
+
+assert(weak_map.has(key_obj_1));
+assert(weak_map.has(key_obj_2));
+assert(weak_map.has(key_obj_3));
+
+assert(weak_map.get(key_obj_1).deref() === key_obj_1);
+assert(weak_map.get(key_obj_2).deref() === target_obj_2);
+assert(weak_map.get(key_obj_3).deref() === target_obj_3);
+
+key_obj_1 = undefined;
+gc();
+assert(weak_map.get(key_obj_1) === undefined);
+assert(weak_ref_3.deref() === undefined);
+
+key_obj_2 = undefined;
+gc();
+assert(weak_map.get(key_obj_2) === undefined);
+assert(weak_ref_4.deref() === target_obj_2);
+
+target_obj_3 = undefined;
+gc();
+assert(weak_map.get(key_obj_3) !== undefined);
+assert(weak_ref_5.deref() === undefined);

tests/test262-esnext-excludelist.xml

@@ -5295,32 +5295,8 @@
   <test id="built-ins/FinalizationRegistry/target-not-callable-throws.js"><reason></reason></test>
   <test id="built-ins/FinalizationRegistry/undefined-newtarget-throws.js"><reason></reason></test>
   <test id="built-ins/FinalizationRegistry/unnaffected-by-poisoned-cleanupCallback.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/constructor.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/instance-extensible.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/length.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/name.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/newtarget-prototype-is-not-object.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prop-desc.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/proto-from-ctor-realm.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/proto.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype-from-newtarget-abrupt.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype-from-newtarget-custom.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype-from-newtarget.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/Symbol.toStringTag.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/constructor.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/deref/custom-this.js"><reason></reason></test>
   <test id="built-ins/WeakRef/prototype/deref/gc-cleanup-not-prevented-with-wr-deref.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/deref/length.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/deref/name.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/deref/prop-desc.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/deref/return-target.js"><reason></reason></test>
   <test id="built-ins/WeakRef/prototype/deref/this-does-not-have-internal-target-throws.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/deref/this-not-object-throws.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/prop-desc.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/prototype/proto.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/returns-new-object-from-constructor.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/target-not-object-throws.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/undefined-newtarget-throws.js"><reason></reason></test>
   <!-- END - ESNext stage 4 proposal: WeakRefs -->
 
   <!-- ESNext stage 4 proposal: Logical Assignment Operators
@@ -8605,7 +8581,6 @@
   <test id="built-ins/TypedArrayConstructors/internals/HasProperty/detached-buffer-realm.js"><reason></reason></test>
   <test id="built-ins/TypedArrayConstructors/internals/Set/BigInt/detached-buffer-realm.js"><reason></reason></test>
   <test id="built-ins/TypedArrayConstructors/internals/Set/detached-buffer-realm.js"><reason></reason></test>
-  <test id="built-ins/WeakRef/proto-from-ctor-realm.js"><reason></reason></test>
   <test id="intl402/Collator/proto-from-ctor-realm.js"><reason></reason></test>
   <test id="intl402/DateTimeFormat/proto-from-ctor-realm.js"><reason></reason></test>
   <test id="intl402/DisplayNames/proto-from-ctor-realm.js"><reason></reason></test>

tests/unit-core/test-api-objecttype.c

@@ -73,6 +73,7 @@ main (void)
   const jerry_char_t number_object[] = "new Number(5)";
   const jerry_char_t regexp_object[] = "new RegExp()";
   const jerry_char_t string_object[] = "new String('foo')";
+  const jerry_char_t weak_ref_object[] = "new WeakRef({})";
 
   test_entry_t entries[] =
   {
@@ -115,6 +116,7 @@ main (void)
     ENTRY_IF (JERRY_OBJECT_TYPE_SYMBOL, EVALUATE (symbol_object), JERRY_FEATURE_SYMBOL),
     ENTRY_IF (JERRY_OBJECT_TYPE_GENERATOR, EVALUATE (generator_object), JERRY_FEATURE_SYMBOL),
     ENTRY_IF (JERRY_OBJECT_TYPE_BIGINT, EVALUATE (bigint_object), JERRY_FEATURE_BIGINT),
+    ENTRY_IF (JERRY_OBJECT_TYPE_WEAKREF, EVALUATE (weak_ref_object), JERRY_FEATURE_WEAKREF),
   };
 
   for (size_t idx = 0; idx < sizeof (entries) / sizeof (entries[0]); idx++)