Clone engine262 in /engine262

engine262/src/intrinsics/FinalizationRegistry.mjs

@@ -0,0 +1,42 @@
+import { surroundingAgent } from '../engine.mjs';
+import { Value } from '../value.mjs';
+import { IsCallable, OrdinaryCreateFromConstructor } from '../abstract-ops/all.mjs';
+import { Q } from '../completion.mjs';
+import { BootstrapConstructor } from './Bootstrap.mjs';
+
+// #sec-finalization-registry-cleanup-callback
+function FinalizationRegistryConstructor([cleanupCallback = Value.undefined], { NewTarget }) {
+  // 1. If NewTarget is undefined, throw a TypeError exception.
+  if (NewTarget === Value.undefined) {
+    return surroundingAgent.Throw('TypeError', 'NotAFunction', 'FinalizationRegistry');
+  }
+  // 2. If IsCallable(cleanupCallback) is false, throw a TypeError exception.
+  if (IsCallable(cleanupCallback) === Value.false) {
+    return surroundingAgent.Throw('TypeError', 'NotAFunction', cleanupCallback);
+  }
+  // 3. Let finalizationGroup be ? OrdinaryCreateFromConstructor(NewTarget, "%FinalizationRegistryPrototype%", « [[Realm]], [[CleanupCallback]], [[Cells]] »).
+  const finalizationGroup = Q(OrdinaryCreateFromConstructor(NewTarget, '%FinalizationRegistry.prototype%', [
+    'Realm',
+    'CleanupCallback',
+    'Cells',
+  ]));
+  // 4. Let fn be the active function object.
+  const fn = surroundingAgent.activeFunctionObject;
+  // 5. Set finalizationGroup.[[Realm]] to fn.[[Realm]].
+  finalizationGroup.Realm = fn.Realm;
+  // 6. Set finalizationGroup.[[CleanupCallback]] to cleanupCallback.
+  finalizationGroup.CleanupCallback = cleanupCallback;
+  // 7. Set finalizationGroup.[[Cells]] to be an empty List.
+  finalizationGroup.Cells = [];
+  // 8. Return finalizationGroup.
+  return finalizationGroup;
+}
+
+export function BootstrapFinalizationRegistry(realmRec) {
+  const cons = BootstrapConstructor(
+    realmRec, FinalizationRegistryConstructor, 'FinalizationRegistry', 1,
+    realmRec.Intrinsics['%FinalizationRegistry.prototype%'], [],
+  );
+
+  realmRec.Intrinsics['%FinalizationRegistry%'] = cons;
+}