LibWeb: Add origin property to window object

Userland/Libraries/LibWeb/Bindings/WindowObject.cpp

@@ -115,6 +115,7 @@ void WindowObject::initialize_global_object()
     define_direct_property("CSS", heap().allocate<CSSNamespace>(*this, *this), 0);
 
     define_native_accessor("localStorage", local_storage_getter, {}, attr);
+    define_native_accessor("origin", origin_getter, {}, attr);
 
     // Legacy
     define_native_accessor("event", event_getter, event_setter, JS::Attribute::Enumerable);
@@ -651,6 +652,13 @@ JS_DEFINE_NATIVE_FUNCTION(WindowObject::post_message)
     return JS::js_undefined();
 }
 
+// https://html.spec.whatwg.org/multipage/webappapis.html#dom-origin
+JS_DEFINE_NATIVE_FUNCTION(WindowObject::origin_getter)
+{
+    auto* impl = TRY(impl_from(vm, global_object));
+    return JS::js_string(vm, impl->associated_document().origin().serialize());
+}
+
 JS_DEFINE_NATIVE_FUNCTION(WindowObject::local_storage_getter)
 {
     auto* impl = TRY(impl_from(vm, global_object));

Userland/Libraries/LibWeb/Bindings/WindowObject.h

@@ -97,6 +97,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(post_message);
 
     JS_DECLARE_NATIVE_FUNCTION(local_storage_getter);
+    JS_DECLARE_NATIVE_FUNCTION(origin_getter);
 
     JS_DECLARE_NATIVE_FUNCTION(alert);
     JS_DECLARE_NATIVE_FUNCTION(confirm);

Userland/Libraries/LibWeb/Origin.h

@@ -66,6 +66,32 @@ public:
         return false;
     }
 
+    // https://html.spec.whatwg.org/multipage/origin.html#ascii-serialisation-of-an-origin
+    String serialize()
+    {
+        // 1. If origin is an opaque origin, then return "null"
+        if (is_opaque())
+            return "null";
+
+        // 2. Otherwise, let result be origin's scheme.
+        StringBuilder result;
+        result.append(protocol());
+
+        // 3. Append "://" to result.
+        result.append("://");
+
+        // 4. Append origin's host, serialized, to result.
+        result.append(host());
+
+        // 5. If origin's port is non-null, append a U+003A COLON character (:), and origin's port, serialized, to result.
+        if (port() != 0) {
+            result.append(":");
+            result.append(String::number(port()));
+        }
+        // 6. Return result
+        return result.to_string();
+    }
+
     bool operator==(Origin const& other) const { return is_same_origin(other); }
     bool operator!=(Origin const& other) const { return !is_same_origin(other); }