LibWeb: Add definitions from '2.2.3. Statuses' in the Fetch spec

Author: https://github.com/linusg
Commit: https://github.com/SerenityOS/serenity/commit/1694279dd8
Pull-request: https://github.com/SerenityOS/serenity/pull/14568
Reviewed-by: https://github.com/trflynn89 ✅

Userland/Libraries/LibWeb/CMakeLists.txt

@@ -121,6 +121,7 @@ set(SOURCES
     Fetch/Infrastructure/URL.cpp
     Fetch/Infrastructure/HTTP/Headers.cpp
     Fetch/Infrastructure/HTTP/Methods.cpp
+    Fetch/Infrastructure/HTTP/Statuses.cpp
     FontCache.cpp
     Geometry/DOMRectList.cpp
     HTML/AttributeNames.cpp

Userland/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Statuses.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/AnyOf.h>
+#include <AK/Array.h>
+#include <LibWeb/Fetch/Infrastructure/HTTP/Statuses.h>
+
+namespace Web::Fetch {
+
+// https://fetch.spec.whatwg.org/#null-body-status
+bool is_null_body_status(Status status)
+{
+    // A null body status is a status that is 101, 103, 204, 205, or 304.
+    return any_of(Array<Status, 5> { 101, 103, 204, 205, 304 }, [&](auto redirect_status) {
+        return status == redirect_status;
+    });
+}
+
+// https://fetch.spec.whatwg.org/#ok-status
+bool is_ok_status(Status status)
+{
+    // An ok status is a status in the range 200 to 299, inclusive.
+    return status >= 200 && status <= 299;
+}
+
+// https://fetch.spec.whatwg.org/#redirect-status
+bool is_redirect_status(Status status)
+{
+    // A redirect status is a status that is 301, 302, 303, 307, or 308.
+    return any_of(Array<Status, 5> { 301, 302, 303, 307, 308 }, [&](auto redirect_status) {
+        return status == redirect_status;
+    });
+}
+
+}

Userland/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Statuses.h

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Forward.h>
+
+namespace Web::Fetch {
+
+// https://fetch.spec.whatwg.org/#concept-status
+// A status is an integer in the range 0 to 999, inclusive.
+using Status = u16;
+
+[[nodiscard]] bool is_null_body_status(Status);
+[[nodiscard]] bool is_ok_status(Status);
+[[nodiscard]] bool is_redirect_status(Status);
+
+}