LibWeb: Add the History object and stub pushState and replaceState

The spec allows us to optionally return from these for any reason.
Our reason is that we don't have all the infrastructure in place yet to
implement them.

Userland/Libraries/LibWeb/Bindings/WindowObject.cpp

@@ -19,6 +19,7 @@
 #include <LibWeb/Bindings/EventTargetPrototype.h>
 #include <LibWeb/Bindings/EventWrapper.h>
 #include <LibWeb/Bindings/EventWrapperFactory.h>
+#include <LibWeb/Bindings/HistoryWrapper.h>
 #include <LibWeb/Bindings/LocationObject.h>
 #include <LibWeb/Bindings/NavigatorObject.h>
 #include <LibWeb/Bindings/NodeWrapperFactory.h>
@@ -57,6 +58,7 @@ 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("history", history_getter, {}, JS::Attribute::Enumerable);
     define_native_accessor("performance", performance_getter, {}, JS::Attribute::Enumerable);
     define_native_accessor("screen", screen_getter, {}, JS::Attribute::Enumerable);
     define_native_accessor("innerWidth", inner_width_getter, {}, JS::Attribute::Enumerable);
@@ -640,4 +642,12 @@ JS_DEFINE_NATIVE_FUNCTION(WindowObject::scroll_by)
     return JS::js_undefined();
 }
 
+JS_DEFINE_NATIVE_FUNCTION(WindowObject::history_getter)
+{
+    auto* impl = impl_from(vm, global_object);
+    if (!impl)
+        return {};
+    return wrap(global_object, impl->associated_document().history());
+}
+
 }

Userland/Libraries/LibWeb/Bindings/WindowObject.h

@@ -64,6 +64,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(document_getter);
 
     JS_DECLARE_NATIVE_FUNCTION(performance_getter);
+    JS_DECLARE_NATIVE_FUNCTION(history_getter);
     JS_DECLARE_NATIVE_FUNCTION(screen_getter);
 
     JS_DECLARE_NATIVE_FUNCTION(event_getter);

Userland/Libraries/LibWeb/Bindings/WindowObjectHelper.h

@@ -182,6 +182,8 @@
 #include <LibWeb/Bindings/HTMLUnknownElementPrototype.h>
 #include <LibWeb/Bindings/HTMLVideoElementConstructor.h>
 #include <LibWeb/Bindings/HTMLVideoElementPrototype.h>
+#include <LibWeb/Bindings/HistoryConstructor.h>
+#include <LibWeb/Bindings/HistoryPrototype.h>
 #include <LibWeb/Bindings/ImageConstructor.h>
 #include <LibWeb/Bindings/ImageDataConstructor.h>
 #include <LibWeb/Bindings/ImageDataPrototype.h>
@@ -259,6 +261,7 @@
     ADD_WINDOW_OBJECT_INTERFACE(Element)                   \
     ADD_WINDOW_OBJECT_INTERFACE(Event)                     \
     ADD_WINDOW_OBJECT_INTERFACE(EventTarget)               \
+    ADD_WINDOW_OBJECT_INTERFACE(History)                   \
     ADD_WINDOW_OBJECT_INTERFACE(HTMLAnchorElement)         \
     ADD_WINDOW_OBJECT_INTERFACE(HTMLAreaElement)           \
     ADD_WINDOW_OBJECT_INTERFACE(HTMLAudioElement)          \

Userland/Libraries/LibWeb/CMakeLists.txt

@@ -77,6 +77,7 @@ set(SOURCES
     HTML/EventNames.cpp
     HTML/FormAssociatedElement.cpp
     HTML/GlobalEventHandlers.cpp
+    HTML/History.cpp
     HTML/HTMLAnchorElement.cpp
     HTML/HTMLAreaElement.cpp
     HTML/HTMLAudioElement.cpp
@@ -329,6 +330,7 @@ libweb_js_wrapper(DOM/Text)
 libweb_js_wrapper(HTML/CanvasRenderingContext2D)
 libweb_js_wrapper(HTML/CloseEvent)
 libweb_js_wrapper(HTML/DOMParser)
+libweb_js_wrapper(HTML/History)
 libweb_js_wrapper(HTML/HTMLAnchorElement)
 libweb_js_wrapper(HTML/HTMLAreaElement)
 libweb_js_wrapper(HTML/HTMLAudioElement)

Userland/Libraries/LibWeb/DOM/Document.cpp

@@ -64,6 +64,7 @@ Document::Document(const URL& url)
     , m_url(url)
     , m_window(Window::create_with_document(*this))
     , m_implementation(DOMImplementation::create(*this))
+    , m_history(HTML::History::create(*this))
 {
     m_style_update_timer = Core::Timer::create_single_shot(0, [this] {
         update_style();

Userland/Libraries/LibWeb/DOM/Document.h

@@ -27,6 +27,7 @@
 #include <LibWeb/DOM/NonElementParentNode.h>
 #include <LibWeb/DOM/ParentNode.h>
 #include <LibWeb/HTML/HTMLScriptElement.h>
+#include <LibWeb/HTML/History.h>
 
 namespace Web::DOM {
 
@@ -276,6 +277,8 @@ public:
 
     bool is_fully_active() const;
 
+    NonnullRefPtr<HTML::History> history() const { return m_history; }
+
 private:
     explicit Document(const URL&);
 
@@ -356,6 +359,8 @@ private:
 
     // https://html.spec.whatwg.org/multipage/semantics.html#script-blocking-style-sheet-counter
     u32 m_script_blocking_style_sheet_counter { 0 };
+
+    NonnullRefPtr<HTML::History> m_history;
 };
 
 }

Userland/Libraries/LibWeb/Forward.h

@@ -223,6 +223,7 @@ class ElementWrapper;
 class EventListenerWrapper;
 class EventTargetWrapper;
 class EventWrapper;
+class HistoryWrapper;
 class HTMLAnchorElementWrapper;
 class HTMLAreaElementWrapper;
 class HTMLAudioElementWrapper;

Userland/Libraries/LibWeb/HTML/History.cpp

@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibWeb/DOM/Document.h>
+#include <LibWeb/HTML/History.h>
+
+namespace Web::HTML {
+
+History::History(DOM::Document& document)
+    : m_associated_document(document)
+{
+}
+
+History::~History()
+{
+}
+
+// https://html.spec.whatwg.org/multipage/history.html#dom-history-pushstate
+DOM::ExceptionOr<void> History::push_state(JS::Value data, String const&, String const& url)
+{
+    // NOTE: The second parameter of this function is intentionally unused.
+    return shared_history_push_replace_state(data, url, IsPush::Yes);
+}
+
+// https://html.spec.whatwg.org/multipage/history.html#dom-history-replacestate
+DOM::ExceptionOr<void> History::replace_state(JS::Value data, String const&, String const& url)
+{
+    // NOTE: The second parameter of this function is intentionally unused.
+    return shared_history_push_replace_state(data, url, IsPush::No);
+}
+
+// https://html.spec.whatwg.org/multipage/history.html#shared-history-push/replace-state-steps
+DOM::ExceptionOr<void> History::shared_history_push_replace_state(JS::Value, String const&, IsPush)
+{
+    // 1. Let document be history's associated Document. (NOTE: Not necessary)
+
+    // 2. If document is not fully active, then throw a "SecurityError" DOMException.
+    if (!m_associated_document.is_fully_active())
+        return DOM::SecurityError::create("Cannot perform pushState or replaceState on a document that isn't fully active.");
+
+    // 3. Optionally, return. (For example, the user agent might disallow calls to these methods that are invoked on a timer,
+    //    or from event listeners that are not triggered in response to a clear user action, or that are invoked in rapid succession.)
+    dbgln("FIXME: Implement shared_history_push_replace_state.");
+    return {};
+
+    // FIXME: Add the rest of the spec steps once they're added.
+}
+
+}

Userland/Libraries/LibWeb/HTML/History.h

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/RefCounted.h>
+#include <AK/Weakable.h>
+#include <LibJS/Heap/Handle.h>
+#include <LibWeb/Bindings/Wrappable.h>
+#include <LibWeb/DOM/ExceptionOr.h>
+#include <LibWeb/Forward.h>
+
+namespace Web::HTML {
+
+class History final
+    : public RefCounted<History>
+    , public Weakable<History>
+    , public Bindings::Wrappable {
+public:
+    using WrapperType = Bindings::HistoryWrapper;
+
+    static NonnullRefPtr<History> create(DOM::Document& document)
+    {
+        return adopt_ref(*new History(document));
+    }
+
+    virtual ~History() override;
+
+    DOM::ExceptionOr<void> push_state(JS::Value data, String const& unused, String const& url);
+    DOM::ExceptionOr<void> replace_state(JS::Value data, String const& unused, String const& url);
+
+private:
+    explicit History(DOM::Document&);
+
+    enum class IsPush {
+        No,
+        Yes,
+    };
+    DOM::ExceptionOr<void> shared_history_push_replace_state(JS::Value data, String const& url, IsPush is_push);
+
+    DOM::Document& m_associated_document;
+};
+
+}

Userland/Libraries/LibWeb/HTML/History.idl

@@ -0,0 +1,5 @@
+[Exposed=Window]
+interface History {
+    undefined pushState(any data, DOMString unused, optional USVString? url = null);
+    undefined replaceState(any data, DOMString unused, optional USVString? url = null);
+};