LibWeb: Add the WritableStreamDefaultController

Userland/Libraries/LibWeb/Streams/WritableStreamDefaultController.cpp

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2023, Matthew Olsson <mattco@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/Streams/WritableStream.h>
+#include <LibWeb/Streams/WritableStreamDefaultController.h>
+
+namespace Web::Streams {
+
+// https://streams.spec.whatwg.org/#ws-default-controller-error
+WebIDL::ExceptionOr<void> WritableStreamDefaultController::error(JS::Value error)
+{
+    // 1. Let state be this.[[stream]].[[state]].
+    auto state = m_stream->state();
+
+    // 2. If state is not "writable", return.
+    if (state != WritableStream::State::Writable)
+        return {};
+
+    // 3. Perform ! WritableStreamDefaultControllerError(this, e).
+    return writable_stream_default_controller_error(*this, error);
+}
+
+// https://streams.spec.whatwg.org/#ws-default-controller-private-abort
+WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>> WritableStreamDefaultController::abort_steps(JS::Value reason)
+{
+    // 1. Let result be the result of performing this.[[abortAlgorithm]], passing reason.
+    auto result = TRY((*m_abort_algorithm)(reason));
+
+    // 2. Perform ! WritableStreamDefaultControllerClearAlgorithms(this).
+    writable_stream_default_controller_clear_algorithms(*this);
+
+    // 3. Return result.
+    return result;
+}
+
+// https://streams.spec.whatwg.org/#ws-default-controller-private-error
+void WritableStreamDefaultController::error_steps()
+{
+    // 1. Perform ! ResetQueue(this).
+    reset_queue(*this);
+}
+
+}