LibWeb: Implement window.name

Right now the only functionality supported is getting/setting via JS
and resetting when browsing cross origin.

The HTML Specification (7.11 Browsing the web) also specifies how the
name should be restored from history entries, but we don't have those
yet.

Userland/Libraries/LibWeb/Bindings/WindowObject.cpp

@@ -68,6 +68,7 @@ void WindowObject::initialize_global_object()
     define_native_accessor("top", top_getter, nullptr, JS::Attribute::Enumerable);
     define_native_accessor("parent", parent_getter, {}, JS::Attribute::Enumerable);
     define_native_accessor("document", document_getter, {}, JS::Attribute::Enumerable);
+    define_native_accessor("name", name_getter, name_setter, JS::Attribute::Enumerable);
     define_native_accessor("history", history_getter, {}, JS::Attribute::Enumerable);
     define_native_accessor("performance", performance_getter, {}, JS::Attribute::Enumerable);
     define_native_accessor("crypto", crypto_getter, {}, JS::Attribute::Enumerable);
@@ -657,6 +658,19 @@ JS_DEFINE_NATIVE_FUNCTION(WindowObject::session_storage_getter)
     return wrap(global_object, *impl->session_storage());
 }
 
+JS_DEFINE_NATIVE_FUNCTION(WindowObject::name_getter)
+{
+    auto* impl = TRY(impl_from(vm, global_object));
+    return JS::js_string(vm, impl->name());
+}
+
+JS_DEFINE_NATIVE_FUNCTION(WindowObject::name_setter)
+{
+    auto* impl = TRY(impl_from(vm, global_object));
+    impl->set_name(TRY(vm.argument(0).to_string(global_object)));
+    return JS::js_undefined();
+}
+
 #define __ENUMERATE(attribute, event_name)                                                                                 \
     JS_DEFINE_NATIVE_FUNCTION(WindowObject::attribute##_getter)                                                            \
     {                                                                                                                      \

Userland/Libraries/LibWeb/Bindings/WindowObject.h

@@ -80,6 +80,9 @@ private:
 
     JS_DECLARE_NATIVE_FUNCTION(document_getter);
 
+    JS_DECLARE_NATIVE_FUNCTION(name_getter);
+    JS_DECLARE_NATIVE_FUNCTION(name_setter);
+
     JS_DECLARE_NATIVE_FUNCTION(performance_getter);
     JS_DECLARE_NATIVE_FUNCTION(history_getter);
     JS_DECLARE_NATIVE_FUNCTION(screen_getter);

Userland/Libraries/LibWeb/HTML/BrowsingContext.cpp

@@ -80,6 +80,19 @@ void BrowsingContext::set_active_document(DOM::Document* document)
     if (m_active_document)
         m_active_document->detach_from_browsing_context({}, *this);
 
+    // https://html.spec.whatwg.org/multipage/browsing-the-web.html#resetBCName
+    // FIXME: The rest of set_active_document does not follow the spec very closely, this just implements the
+    //   relevant steps for resetting the browsing context name and should be updated closer to the spec once
+    //   the other parts of history handling/navigating are implemented
+    // 3. If newDocument's origin is not same origin with the current entry's document's origin, then:
+    if (!document || !m_active_document || !document->origin().is_same_origin(m_active_document->origin())) {
+        // 3. If the browsing context is a top-level browsing context, but not an auxiliary browsing context
+        //    whose disowned is false, then set the browsing context's name to the empty string.
+        // FIXME: this is not checking the second part of the condition yet
+        if (is_top_level())
+            m_name = String::empty();
+    }
+
     m_active_document = document;
 
     if (m_active_document) {

Userland/Libraries/LibWeb/HTML/BrowsingContext.h

@@ -107,6 +107,9 @@ public:
 
     RefPtr<DOM::Node> currently_focused_area();
 
+    String const& name() const { return m_name; }
+    void set_name(String const& name) { m_name = name; }
+
 private:
     explicit BrowsingContext(Page&, HTML::BrowsingContextContainer*);
 
@@ -129,6 +132,7 @@ private:
     HashTable<ViewportClient*> m_viewport_clients;
 
     HashMap<AK::URL, size_t> m_frame_nesting_levels;
+    String m_name;
 };
 
 }

Userland/Libraries/LibWeb/HTML/Window.cpp

@@ -613,4 +613,24 @@ DOM::ExceptionOr<void> Window::post_message(JS::Value message, String const&)
     return {};
 }
 
+// https://html.spec.whatwg.org/multipage/window-object.html#dom-name
+String Window::name() const
+{
+    // 1. If this's browsing context is null, then return the empty string.
+    if (!browsing_context())
+        return String::empty();
+    // 2. Return this's browsing context's name.
+    return browsing_context()->name();
+}
+
+// https://html.spec.whatwg.org/multipage/window-object.html#dom-name
+void Window::set_name(String const& name)
+{
+    // 1. If this's browsing context is null, then return.
+    if (!browsing_context())
+        return;
+    // 2. Set this's browsing context's name to the given value.
+    browsing_context()->set_name(name);
+}
+
 }

Userland/Libraries/LibWeb/HTML/Window.h

@@ -110,6 +110,9 @@ public:
 
     DOM::ExceptionOr<void> post_message(JS::Value, String const& target_origin);
 
+    String name() const;
+    void set_name(String const&);
+
 private:
     explicit Window(DOM::Document&);