LibJS: Add DisposableStack{, Prototype, Constructor}

Since the async parts of the spec are not stage 3 at this point we don't
add AsyncDisposableStack.

Userland/Libraries/LibJS/Runtime/DisposableStackConstructor.cpp

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2022, David Tuin <davidot@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/AbstractOperations.h>
+#include <LibJS/Runtime/DisposableStack.h>
+#include <LibJS/Runtime/DisposableStackConstructor.h>
+
+namespace JS {
+
+DisposableStackConstructor::DisposableStackConstructor(Realm& realm)
+    : NativeFunction(realm.vm().names.DisposableStack.as_string(), *realm.intrinsics().function_prototype())
+{
+}
+
+void DisposableStackConstructor::initialize(Realm& realm)
+{
+    auto& vm = this->vm();
+    NativeFunction::initialize(realm);
+
+    // 26.2.2.1 DisposableStack.prototype, https://tc39.es/ecma262/#sec-finalization-registry.prototype
+    define_direct_property(vm.names.prototype, realm.intrinsics().disposable_stack_prototype(), 0);
+
+    define_direct_property(vm.names.length, Value(0), Attribute::Configurable);
+}
+
+// 11.3.1.1 DisposableStack ( ), https://tc39.es/proposal-explicit-resource-management/#sec-disposablestack
+ThrowCompletionOr<Value> DisposableStackConstructor::call()
+{
+    auto& vm = this->vm();
+
+    // 1. If NewTarget is undefined, throw a TypeError exception.
+    return vm.throw_completion<TypeError>(ErrorType::ConstructorWithoutNew, vm.names.DisposableStack);
+}
+
+// 11.3.1.1 DisposableStack ( ), https://tc39.es/proposal-explicit-resource-management/#sec-disposablestack
+ThrowCompletionOr<NonnullGCPtr<Object>> DisposableStackConstructor::construct(FunctionObject& new_target)
+{
+    auto& vm = this->vm();
+
+    // 2. Let disposableStack be ? OrdinaryCreateFromConstructor(NewTarget, "%DisposableStack.prototype%", « [[DisposableState]], [[DisposableResourceStack]] »).
+    // 3. Set disposableStack.[[DisposableState]] to pending.
+    // 4. Set disposableStack.[[DisposableResourceStack]] to a new empty List.
+    // 5. Return disposableStack.
+    return TRY(ordinary_create_from_constructor<DisposableStack>(vm, new_target, &Intrinsics::disposable_stack_prototype, Vector<DisposableResource> {}));
+}
+
+}