[Navigation] Implement navigation.updateCurrentEntry()

https://bugs.webkit.org/show_bug.cgi?id=268261

Reviewed by Alex Christensen.

This implements `navigation.UpdateCurrentEntry()`, both the method storing state, and emitting the currententryupdated event.

https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-navigation-updatecurrententry

* LayoutTests/TestExpectations:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/anchor-click-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/constructor-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-back-same-doc-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-pushState-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-replaceState-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/location-api-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-back-forward-same-doc-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-navigate-preventDefault-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-navigate-replace-same-doc-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-navigate-same-doc-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-updateCurrentEntry-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/basic-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/cross-document-away-and-back-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/cross-document-location-api-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/exception-order-initial-about-blank-unserializablestate-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/exception-order-not-fully-active-unserializablestate-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/history-pushState-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/history-replaceState-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/location-reload-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/not-fully-active-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/opaque-origin-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/same-document-away-and-back-location-api-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/unserializable-expected.txt:
* Source/WebCore/page/Navigation.cpp:
(WebCore::Navigation::updateCurrentEntry):
* Source/WebCore/page/Navigation.h:
* Source/WebCore/page/Navigation.idl:
* Source/WebCore/page/NavigationHistoryEntry.cpp:
(WebCore::NavigationHistoryEntry::getState const):
* Source/WebCore/page/NavigationHistoryEntry.h:
* Source/WebCore/page/NavigationHistoryEntry.idl:

Canonical link: https://commits.webkit.org/274321@main

LayoutTests/TestExpectations

@@ -6889,11 +6889,11 @@ imported/w3c/web-platform-tests/html/semantics/interactive-elements/the-dialog-e
 
 # Navigation API is not yet fully implemented
 webkit.org/b/258384 imported/w3c/web-platform-tests/navigation-api [ Skip ]
+imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/ [ Pass ]
+imported/w3c/web-platform-tests/navigation-api/currententrychange-event/ [ Pass ]
+imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-back-forward-same-doc.html [ Skip ]
+imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-back-same-doc.html [ Skip ]
 imported/w3c/web-platform-tests/navigation-api/commit-behavior/after-transition-uncancelable.html [ Pass ]
-imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigate-from-initial-about-blank.html [ Pass ]
-imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigate-from-initial-about-blank-same-doc.html [ Pass ]
-imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigate-from-initial-about-blank-same-doc-popup.html [ Pass ]
-imported/w3c/web-platform-tests/navigation-api/currententrychange-event/not-on-load.html [ Pass ]
 imported/w3c/web-platform-tests/navigation-api/navigate-event/navigate-to-javascript.html [ Pass ]
 imported/w3c/web-platform-tests/navigation-api/navigate-event/navigatesuccess-cross-document.html [ Pass ]
 imported/w3c/web-platform-tests/navigation-api/navigate-event/replaceState-in-unload-then-remove-iframe.html [ Pass ]
@@ -6909,7 +6909,10 @@ imported/w3c/web-platform-tests/navigation-api/ordering-and-transition/transitio
 imported/w3c/web-platform-tests/navigation-api/scroll-behavior/after-transition-intercept-handler-modifies.html [ Pass ]
 imported/w3c/web-platform-tests/navigation-api/scroll-behavior/scroll-on-synthetic-event.html [ Pass ]
 imported/w3c/web-platform-tests/navigation-api/scroll-behavior/scroll-without-intercept.html [ Pass ]
-imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/no-args.html [ Pass ]
+imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/same-document-away-and-back-location-api.html [ Skip ]
+imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/cross-document-away-and-back.html [ Skip ]
+imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/cross-document-location-api.html [ Skip ]
+imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/location-reload.html [ Skip ]
 
 # -- View Transitions -- #
 # Reftest failures:

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/anchor-click-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for link click null is not an object (evaluating 'navigation.currentEntry.index')
+FAIL currententrychange fires for link click assert_true: expected true got false
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/constructor-expected.txt

@@ -1,6 +1,6 @@
 
 PASS can't bypass required members by omitting the dictionary entirely
 PASS from is required
-FAIL all properties are reflected back Type error
-FAIL defaults are as expected Type error
+PASS all properties are reflected back
+PASS defaults are as expected
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-back-same-doc-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for history.back() promise_test: Unhandled rejection with value: object "TypeError: null is not an object (evaluating 'navigation.currentEntry.index')"
+FAIL currententrychange fires for history.back() assert_equals: expected 3 but got 2
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-pushState-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for history.pushState() null is not an object (evaluating 'navigation.currentEntry.index')
+FAIL currententrychange fires for history.pushState() assert_true: expected true got false
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/history-replaceState-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for history.replaceState() null is not an object (evaluating 'navigation.currentEntry.index')
+FAIL currententrychange fires for history.replaceState() assert_true: expected true got false
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/location-api-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for location API navigations null is not an object (evaluating 'navigation.currentEntry.index')
+FAIL currententrychange fires for location API navigations assert_true: expected true got false
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-back-forward-same-doc-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for same-document navigation.back() and navigation.forward() promise_test: Unhandled rejection with value: object "TypeError: null is not an object (evaluating 'navigation.currentEntry.index')"
+FAIL currententrychange fires for same-document navigation.back() and navigation.forward() assert_equals: expected 3 but got 2
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-navigate-preventDefault-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange does not fire when onnavigate preventDefault() is called promise_test: Unhandled rejection with value: object "TypeError: undefined is not an object (evaluating 'promise.then')"
+FAIL currententrychange does not fire when onnavigate preventDefault() is called assert_unreached: Should have rejected: undefined Reached unreachable code
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-navigate-replace-same-doc-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for navigation.navigate() with replace promise_test: Unhandled rejection with value: object "TypeError: null is not an object (evaluating 'navigation.currentEntry.index')"
+FAIL currententrychange fires for navigation.navigate() with replace assert_true: expected true got false
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-navigate-same-doc-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for navigation.navigate() promise_test: Unhandled rejection with value: object "TypeError: null is not an object (evaluating 'navigation.currentEntry.index')"
+FAIL currententrychange fires for navigation.navigate() assert_true: expected true got false
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/currententrychange-event/navigation-updateCurrentEntry-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL currententrychange fires for navigation.updateCurrentEntry() assert_equals: expected 1 but got 0
+PASS currententrychange fires for navigation.updateCurrentEntry()
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/basic-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL updateCurrentEntry() works as expected null is not an object (evaluating 'navigation.currentEntry.getState')
+PASS updateCurrentEntry() works as expected
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/cross-document-away-and-back-expected.txt

@@ -1,4 +1,4 @@
 
 
-FAIL entry.getState() behavior after navigating away and back assert_equals: expected 1 but got 0
+FAIL entry.getState() behavior after navigating away and back assert_equals: expected 1 but got 4
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/cross-document-location-api-expected.txt

@@ -1,4 +1,4 @@
 
 
-FAIL entry.getState() behavior after cross-document location API navigation assert_equals: expected 1 but got 0
+FAIL entry.getState() behavior after cross-document location API navigation assert_equals: expected 1 but got 4
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/exception-order-initial-about-blank-unserializablestate-expected.txt

@@ -2,5 +2,5 @@
 
 FAIL updateCurrentEntry() with unserializable state on the initial about:blank must throw an "InvalidStateError", not a "DataCloneError" assert_throws_dom: function "() => {
     iframe.contentWindow.navigation.updateCurrentEntry({ state: document.body });
-  }" did not throw
+  }" threw object "DataCloneError: The object can not be cloned." that is not a DOMException InvalidStateError: property "code" is equal to 25, expected 11
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/exception-order-not-fully-active-unserializablestate-expected.txt

@@ -1,5 +1,3 @@
 
-FAIL updateCurrentEntry() with unserializable state while not fully active must throw an "InvalidStateError", not a "DataCloneError" assert_throws_dom: function "() => {
-      wNavigation.updateCurrentEntry({ state: document.body });
-    }" did not throw
+PASS updateCurrentEntry() with unserializable state while not fully active must throw an "InvalidStateError", not a "DataCloneError"
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/history-pushState-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL entry.getState() after history.pushState() null is not an object (evaluating 'navigation.currentEntry.getState')
+FAIL entry.getState() after history.pushState() assert_equals: expected (undefined) undefined but got (object) object "[object Object]"
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/history-replaceState-expected.txt

@@ -1,3 +1,3 @@
 
-FAIL entry.getState() after history.replaceState() null is not an object (evaluating 'navigation.currentEntry.getState')
+FAIL entry.getState() after history.replaceState() assert_equals: expected (undefined) undefined but got (object) object "[object Object]"
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/location-reload-expected.txt

@@ -1,4 +1,4 @@
 
 
-FAIL entry.getState() after location.reload() assert_equals: expected 1 but got 0
+FAIL entry.getState() after location.reload() assert_equals: expected 1 but got 4
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/not-fully-active-expected.txt

@@ -1,5 +1,3 @@
 
-FAIL updateCurrentEntry() must throw if the document is not fully active assert_throws_dom: function "() => {
-      wNavigation.updateCurrentEntry({ state: 1 });
-    }" did not throw
+PASS updateCurrentEntry() must throw if the document is not fully active
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/opaque-origin-expected.txt

@@ -1,6 +1,4 @@
 
 
-FAIL navigation.updateCurrentEntry() in an opaque origin iframe assert_throws_dom: function "() => {
-    navigation.updateCurrentEntry({ state: 1 });
-  }" did not throw
+PASS navigation.updateCurrentEntry() in an opaque origin iframe
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/same-document-away-and-back-location-api-expected.txt

@@ -1,10 +1,10 @@
-CONSOLE MESSAGE: Unhandled Promise Rejection: TypeError: null is not an object (evaluating 'entry0.index')
+CONSOLE MESSAGE: Unhandled Promise Rejection: Error: assert_equals: expected 3 but got 2
 
-Harness Error (FAIL), message = Unhandled rejection: null is not an object (evaluating 'entry0.index')
+Harness Error (FAIL), message = Unhandled rejection: assert_equals: expected 3 but got 2
 
 TIMEOUT entry.getState() behavior after navigating away using the location API, then back Test timed out
 
-Harness Error (FAIL), message = Unhandled rejection: null is not an object (evaluating 'entry0.index')
+Harness Error (FAIL), message = Unhandled rejection: assert_equals: expected 3 but got 2
 
 TIMEOUT entry.getState() behavior after navigating away using the location API, then back Test timed out
 

LayoutTests/imported/w3c/web-platform-tests/navigation-api/updateCurrentEntry-method/unserializable-expected.txt

@@ -1,8 +1,6 @@
 
 
-FAIL updateCurrentEntry() must throw if state is unserializable (WritableStream) assert_throws_dom: function "() => {
-      iframe.contentWindow.navigation.updateCurrentEntry({ state: new WritableStream() });
-    }" did not throw
+PASS updateCurrentEntry() must throw if state is unserializable (WritableStream)
 FAIL updateCurrentEntry() must throw if state is unserializable (SharedArrayBuffer) assert_throws_dom: function "() => {
       iframe.contentWindow.navigation.updateCurrentEntry({ state: buffer });
     }" did not throw

Source/WebCore/history/HistoryItem.cpp

@@ -109,6 +109,7 @@ void HistoryItem::reset()
     m_itemSequenceNumber = generateSequenceNumber();
 
     m_stateObject = nullptr;
+    m_navigationAPIStateObject = nullptr;
     m_documentSequenceNumber = generateSequenceNumber();
 
     m_formData = nullptr;
@@ -278,6 +279,12 @@ void HistoryItem::setStateObject(RefPtr<SerializedScriptValue>&& object)
     notifyChanged();
 }
 
+// https://html.spec.whatwg.org/multipage/browsing-the-web.html#she-navigation-api-state
+void HistoryItem::setNavigationAPIStateObject(RefPtr<SerializedScriptValue>&& object)
+{
+    m_navigationAPIStateObject = WTFMove(object);
+}
+
 void HistoryItem::addChildItem(Ref<HistoryItem>&& child)
 {
     ASSERT(!childItemWithTarget(child->target()));

Source/WebCore/history/HistoryItem.h

@@ -131,6 +131,9 @@ class HistoryItem : public RefCounted<HistoryItem>, public CanMakeWeakPtr<Histor
     WEBCORE_EXPORT void setStateObject(RefPtr<SerializedScriptValue>&&);
     SerializedScriptValue* stateObject() const { return m_stateObject.get(); }
 
+    void setNavigationAPIStateObject(RefPtr<SerializedScriptValue>&&);
+    SerializedScriptValue* navigationAPIStateObject() const { return m_navigationAPIStateObject.get(); }
+
     void setItemSequenceNumber(long long number) { m_itemSequenceNumber = number; }
     long long itemSequenceNumber() const { return m_itemSequenceNumber; }
 
@@ -255,6 +258,9 @@ class HistoryItem : public RefCounted<HistoryItem>, public CanMakeWeakPtr<Histor
     // Support for HTML5 History
     RefPtr<SerializedScriptValue> m_stateObject;
 
+    // Navigation API
+    RefPtr<SerializedScriptValue> m_navigationAPIStateObject;
+
     // info used to repost form data
     RefPtr<FormData> m_formData;
     String m_formContentType;

Source/WebCore/page/Navigation.cpp

@@ -26,8 +26,12 @@
 #include "config.h"
 #include "Navigation.h"
 
+#include "Exception.h"
 #include "HistoryItem.h"
 #include "JSNavigationHistoryEntry.h"
+#include "NavigationCurrentEntryChangeEvent.h"
+#include "SerializedScriptValue.h"
+#include <optional>
 #include <wtf/IsoMallocInlines.h>
 
 namespace WebCore {
@@ -41,10 +45,10 @@ Navigation::Navigation(ScriptExecutionContext* context, LocalDOMWindow& window)
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#initialize-the-navigation-api-entries-for-a-new-document
-void Navigation::initializeEntries(const Ref<HistoryItem>& currentItem, const Vector<Ref<HistoryItem>>& items)
+void Navigation::initializeEntries(const Ref<HistoryItem>& currentItem, Vector<Ref<HistoryItem>>& items)
 {
     for (Ref item : items)
-        m_entries.append(NavigationHistoryEntry::create(protectedScriptExecutionContext().get(), item->url()));
+        m_entries.append(NavigationHistoryEntry::create(protectedScriptExecutionContext().get(), item));
     m_currentEntryIndex = items.find(currentItem);
 }
 
@@ -130,8 +134,30 @@ Navigation::Result Navigation::forward(Options&&, Ref<DeferredPromise>&& committ
     return result;
 }
 
-void Navigation::updateCurrentEntry(UpdateCurrentEntryOptions&&)
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#dom-navigation-updatecurrententry
+ExceptionOr<void> Navigation::updateCurrentEntry(JSDOMGlobalObject& globalObject, UpdateCurrentEntryOptions&& options)
 {
+    if (!window()->frame() || !window()->frame()->document())
+        return Exception { ExceptionCode::InvalidStateError };
+
+    auto current = currentEntry();
+    if (!current)
+        return Exception { ExceptionCode::InvalidStateError };
+
+    auto serializedState = SerializedScriptValue::create(globalObject, options.state, SerializationForStorage::Yes, SerializationErrorMode::Throwing);
+    if (!serializedState)
+        return { };
+
+    current->setState(WTFMove(serializedState));
+
+    auto currentEntryChangeEvent = NavigationCurrentEntryChangeEvent::create({ "currententrychange"_s }, {
+        { false, false, false },
+        std::nullopt,
+        current
+    });
+    dispatchEvent(currentEntryChangeEvent);
+
+    return { };
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#has-entries-and-events-disabled

Source/WebCore/page/Navigation.h

@@ -82,7 +82,7 @@ class Navigation final : public RefCounted<Navigation>, public EventTarget, publ
     bool canGoBack() const { return m_canGoBack; };
     bool canGoForward() const { return m_canGoForward; };
 
-    void initializeEntries(const Ref<HistoryItem>& currentItem, const Vector<Ref<HistoryItem>> &items);
+    void initializeEntries(const Ref<HistoryItem>& currentItem, Vector<Ref<HistoryItem>> &items);
 
     Result navigate(const String& url, NavigateOptions&&, Ref<DeferredPromise>&&, Ref<DeferredPromise>&&);
 
@@ -92,7 +92,7 @@ class Navigation final : public RefCounted<Navigation>, public EventTarget, publ
     Result back(Options&&, Ref<DeferredPromise>&&, Ref<DeferredPromise>&&);
     Result forward(Options&&, Ref<DeferredPromise>&&, Ref<DeferredPromise>&&);
 
-    void updateCurrentEntry(UpdateCurrentEntryOptions&&);
+    ExceptionOr<void> updateCurrentEntry(JSDOMGlobalObject&, UpdateCurrentEntryOptions&&);
 
 private:
     Navigation(ScriptExecutionContext*, LocalDOMWindow&);

Source/WebCore/page/Navigation.idl

@@ -5,7 +5,7 @@
 ] interface Navigation : EventTarget {
   sequence<NavigationHistoryEntry> entries();
   readonly attribute NavigationHistoryEntry? currentEntry;
-  undefined updateCurrentEntry(NavigationUpdateCurrentEntryOptions options);
+  [CallWith=CurrentGlobalObject] undefined updateCurrentEntry(NavigationUpdateCurrentEntryOptions options);
   readonly attribute NavigationTransition? transition;
 
   readonly attribute boolean canGoBack;

Source/WebCore/page/NavigationHistoryEntry.cpp

@@ -26,14 +26,25 @@
 #include "config.h"
 #include "NavigationHistoryEntry.h"
 
+#include "JSDOMGlobalObject.h"
 #include "ScriptExecutionContext.h"
+#include "SerializedScriptValue.h"
 #include <JavaScriptCore/JSCJSValueInlines.h>
 #include <wtf/IsoMallocInlines.h>
 
 namespace WebCore {
 
 WTF_MAKE_ISO_ALLOCATED_IMPL(NavigationHistoryEntry);
 
+NavigationHistoryEntry::NavigationHistoryEntry(ScriptExecutionContext* context, Ref<HistoryItem>& historyItem)
+    : ContextDestructionObserver(context)
+    , m_url(historyItem->url())
+    , m_key(WTF::UUID::createVersion4())
+    , m_id(WTF::UUID::createVersion4())
+    , m_associatedHistoryItem(historyItem)
+{
+}
+
 NavigationHistoryEntry::NavigationHistoryEntry(ScriptExecutionContext* context, const URL& url)
     : ContextDestructionObserver(context)
     , m_url(url)
@@ -52,4 +63,24 @@ EventTargetInterface NavigationHistoryEntry::eventTargetInterface() const
     return NavigationHistoryEntryEventTargetInterfaceType;
 }
 
+JSC::JSValue NavigationHistoryEntry::getState(JSDOMGlobalObject& globalObject) const
+{
+    if (!m_associatedHistoryItem)
+        return JSC::jsUndefined();
+
+    auto stateObject = m_associatedHistoryItem->get().navigationAPIStateObject();
+    if (!stateObject)
+        return JSC::jsUndefined();
+
+    return stateObject->deserialize(globalObject, &globalObject, SerializationErrorMode::Throwing);
+}
+
+void NavigationHistoryEntry::setState(RefPtr<SerializedScriptValue>&& state)
+{
+    if (!m_associatedHistoryItem)
+        return;
+
+    m_associatedHistoryItem->get().setNavigationAPIStateObject(WTFMove(state));
+}
+
 } // namespace WebCore

Source/WebCore/page/NavigationHistoryEntry.h

@@ -28,6 +28,7 @@
 #include "ContextDestructionObserver.h"
 #include "EventHandler.h"
 #include "EventTarget.h"
+#include "HistoryItem.h"
 #include <wtf/RefCounted.h>
 #include <wtf/UUID.h>
 
@@ -37,22 +38,29 @@ class JSValue;
 
 namespace WebCore {
 
+class SerializedScriptValue;
+class HistoryItem;
+
 class NavigationHistoryEntry final : public RefCounted<NavigationHistoryEntry>, public EventTarget, public ContextDestructionObserver {
     WTF_MAKE_ISO_ALLOCATED(NavigationHistoryEntry);
 public:
     using RefCounted<NavigationHistoryEntry>::ref;
     using RefCounted<NavigationHistoryEntry>::deref;
 
+    static Ref<NavigationHistoryEntry> create(ScriptExecutionContext* context, Ref<HistoryItem>& historyItem) { return adoptRef(*new NavigationHistoryEntry(context, historyItem)); }
     static Ref<NavigationHistoryEntry> create(ScriptExecutionContext* context, const URL& url) { return adoptRef(*new NavigationHistoryEntry(context, url)); }
 
     const String& url() const { return m_url.string(); };
     String key() const { return m_key.toString(); };
     String id() const { return m_id.toString(); };
     uint64_t index() const { return m_index; };
     bool sameDocument() const { return m_sameDocument; };
-    const JSC::JSValue& getState() const { return m_state; };
+    JSC::JSValue getState(JSDOMGlobalObject&) const;
+
+    void setState(RefPtr<SerializedScriptValue>&&);
 
 private:
+    NavigationHistoryEntry(ScriptExecutionContext*, Ref<HistoryItem>&);
     NavigationHistoryEntry(ScriptExecutionContext*, const URL&);
 
     EventTargetInterface eventTargetInterface() const final;
@@ -64,7 +72,8 @@ class NavigationHistoryEntry final : public RefCounted<NavigationHistoryEntry>,
     const WTF::UUID m_key;
     const WTF::UUID m_id;
     uint64_t m_index;
-    JSC::JSValue m_state;
+    // TODO: Every entry is supposed to have an associated history item.
+    std::optional<Ref<HistoryItem>> m_associatedHistoryItem;
     bool m_sameDocument;
 };