LibWeb/HTML: Use relevant global object's document in History

Corresponds to dba6e7b6c2
and 4c0401186c

The spec algorithms now use "the relevant global object's associated
document", so remove the concept of the History object itself having an
associated document. The spec has also combined the implementations for
forward/back/go so I've matched that too.

Libraries/LibWeb/DOM/Document.cpp

@@ -3797,7 +3797,7 @@ CSS::StyleSheetList const& Document::style_sheets() const
 GC::Ref<HTML::History> Document::history()
 {
     if (!m_history)
-        m_history = HTML::History::create(realm(), *this);
+        m_history = HTML::History::create(realm());
     return *m_history;
 }
 

Libraries/LibWeb/HTML/History.cpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
+ * Copyright (c) 2025, Sam Atkins <sam@ladybird.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -17,14 +18,13 @@ namespace Web::HTML {
 
 GC_DEFINE_ALLOCATOR(History);
 
-GC::Ref<History> History::create(JS::Realm& realm, DOM::Document& document)
+GC::Ref<History> History::create(JS::Realm& realm)
 {
-    return realm.create<History>(realm, document);
+    return realm.create<History>(realm);
 }
 
-History::History(JS::Realm& realm, DOM::Document& document)
+History::History(JS::Realm& realm)
     : PlatformObject(realm)
-    , m_associated_document(document)
 {
 }
 
@@ -39,7 +39,6 @@ void History::initialize(JS::Realm& realm)
 void History::visit_edges(Cell::Visitor& visitor)
 {
     Base::visit_edges(visitor);
-    visitor.visit(m_associated_document);
     visitor.visit(m_state);
 }
 
@@ -61,7 +60,7 @@ WebIDL::ExceptionOr<void> History::replace_state(JS::Value data, String const&,
 WebIDL::ExceptionOr<u64> History::length() const
 {
     // 1. If this's relevant global object's associated Document is not fully active, then throw a "SecurityError" DOMException.
-    if (!m_associated_document->is_fully_active())
+    if (!as<Window>(relevant_global_object(*this)).associated_document().is_fully_active())
         return WebIDL::SecurityError::create(realm(), "Cannot perform length on a document that isn't fully active."_string);
 
     // 2. Return this's length.
@@ -72,7 +71,7 @@ WebIDL::ExceptionOr<u64> History::length() const
 WebIDL::ExceptionOr<JS::Value> History::state() const
 {
     // 1. If this's relevant global object's associated Document is not fully active, then throw a "SecurityError" DOMException.
-    if (!m_associated_document->is_fully_active())
+    if (!as<Window>(relevant_global_object(*this)).associated_document().is_fully_active())
         return WebIDL::SecurityError::create(realm(), "Cannot perform state on a document that isn't fully active."_string);
 
     // 2. Return this's state.
@@ -84,48 +83,49 @@ JS::Value History::unsafe_state() const
     return m_state;
 }
 
+// https://html.spec.whatwg.org/multipage/nav-history-apis.html#delta-traverse
+WebIDL::ExceptionOr<void> History::delta_traverse(WebIDL::Long delta)
+{
+    // 1. Let document be history's relevant global object's associated Document.
+    auto& document = as<Window>(relevant_global_object(*this)).associated_document();
+
+    // 2. If document is not fully active, then throw a "SecurityError" DOMException.
+    if (!document.is_fully_active())
+        return WebIDL::SecurityError::create(realm(), "Cannot perform go on a document that isn't fully active."_string);
+
+    // 3. If delta is 0, then reload document's node navigable, and return.
+    if (delta == 0) {
+        VERIFY(document.navigable());
+        document.navigable()->reload();
+        return {};
+    }
+
+    // 4. Traverse the history by a delta given document's node navigable's traversable navigable, delta, and with
+    //    sourceDocument set to document.
+    document.navigable()->traversable_navigable()->traverse_the_history_by_delta(delta, document);
+
+    return {};
+}
+
 // https://html.spec.whatwg.org/multipage/history.html#dom-history-go
 WebIDL::ExceptionOr<void> History::go(WebIDL::Long delta = 0)
 {
-    // 1. Let document be this's associated Document.
-
-    // 2. If document is not fully active, then throw a "SecurityError" DOMException.
-    if (!m_associated_document->is_fully_active())
-        return WebIDL::SecurityError::create(realm(), "Cannot perform go on a document that isn't fully active."_string);
-
-    VERIFY(m_associated_document->navigable());
-
-    // 3. If delta is 0, then reload document's node navigable.
-    if (delta == 0)
-        m_associated_document->navigable()->reload();
-
-    // 4. Traverse the history by a delta given document's node navigable's traversable navigable, delta, and with sourceDocument set to document.
-    auto traversable = m_associated_document->navigable()->traversable_navigable();
-    traversable->traverse_the_history_by_delta(delta);
-
-    return {};
+    // The go(delta) method steps are to delta traverse this given delta.
+    return delta_traverse(delta);
 }
 
 // https://html.spec.whatwg.org/multipage/history.html#dom-history-back
 WebIDL::ExceptionOr<void> History::back()
 {
-    // 1. Let document be this's associated Document.
-    // 2. If document is not fully active, then throw a "SecurityError" DOMException.
-    // NOTE: We already did this check in `go` method, so skip the fully active check here.
-
-    // 3. Traverse the history by a delta with −1 and document's browsing context.
-    return go(-1);
+    // The back() method steps are to delta traverse this given −1.
+    return delta_traverse(-1);
 }
 
 // https://html.spec.whatwg.org/multipage/history.html#dom-history-forward
 WebIDL::ExceptionOr<void> History::forward()
 {
-    // 1. Let document be this's associated Document.
-    // 2. If document is not fully active, then throw a "SecurityError" DOMException.
-    // NOTE: We already did this check in `go` method, so skip the fully active check here.
-
-    // 3. Traverse the history by a delta with +1 and document's browsing context.
-    return go(1);
+    // The forward() method steps are to delta traverse this given +1.
+    return delta_traverse(1);
 }
 
 // https://html.spec.whatwg.org/multipage/nav-history-apis.html#can-have-its-url-rewritten
@@ -173,11 +173,11 @@ WebIDL::ExceptionOr<void> History::shared_history_push_replace_state(JS::Value d
 {
     auto& vm = this->vm();
 
-    // 1. Let document be history's associated Document.
-    auto& document = m_associated_document;
+    // 1. Let document be history's relevant global object's associated Document.
+    auto& document = as<Window>(relevant_global_object(*this)).associated_document();
 
     // 2. If document is not fully active, then throw a "SecurityError" DOMException.
-    if (!document->is_fully_active())
+    if (!document.is_fully_active())
         return WebIDL::SecurityError::create(realm(), "Cannot perform pushState or replaceState on a document that isn't fully active."_string);
 
     // 3. Optionally, throw a "SecurityError" DOMException. (For example, the user agent might disallow calls to these
@@ -191,7 +191,7 @@ WebIDL::ExceptionOr<void> History::shared_history_push_replace_state(JS::Value d
     auto serialized_data = serialized_data_or_error.is_error() ? MUST(structured_serialize_for_storage(vm, JS::js_null())) : serialized_data_or_error.release_value();
 
     // 5. Let newURL be document's URL.
-    auto new_url = document->url();
+    auto new_url = document.url();
 
     // 6. If url is not null or the empty string, then:
     if (url.has_value() && !url->is_empty()) {
@@ -234,11 +234,12 @@ WebIDL::ExceptionOr<void> History::shared_history_push_replace_state(JS::Value d
 WebIDL::ExceptionOr<Bindings::ScrollRestoration> History::scroll_restoration() const
 {
     // 1. If this's relevant global object's associated Document is not fully active, then throw a "SecurityError" DOMException.
-    if (!m_associated_document->is_fully_active())
+    auto& this_relevant_global_object = as<Window>(relevant_global_object(*this));
+    if (!this_relevant_global_object.associated_document().is_fully_active())
         return WebIDL::SecurityError::create(realm(), "Cannot obtain scroll restoration mode for a document that isn't fully active."_string);
 
-    // 2. Return this's node navigable's active session history entry's scroll restoration mode.
-    auto scroll_restoration_mode = m_associated_document->navigable()->active_session_history_entry()->scroll_restoration_mode();
+    // 2. Return this's relevant global object's navigable's active session history entry's scroll restoration mode.
+    auto scroll_restoration_mode = this_relevant_global_object.navigable()->active_session_history_entry()->scroll_restoration_mode();
     switch (scroll_restoration_mode) {
     case ScrollRestorationMode::Auto:
         return Bindings::ScrollRestoration::Auto;
@@ -252,11 +253,12 @@ WebIDL::ExceptionOr<Bindings::ScrollRestoration> History::scroll_restoration() c
 WebIDL::ExceptionOr<void> History::set_scroll_restoration(Bindings::ScrollRestoration scroll_restoration)
 {
     // 1. If this's relevant global object's associated Document is not fully active, then throw a "SecurityError" DOMException.
-    if (!m_associated_document->is_fully_active())
+    auto& this_relevant_global_object = as<Window>(relevant_global_object(*this));
+    if (!this_relevant_global_object.associated_document().is_fully_active())
         return WebIDL::SecurityError::create(realm(), "Cannot set scroll restoration mode for a document that isn't fully active."_string);
 
-    // 2. Set this's node navigable's active session history entry's scroll restoration mode to the given value.
-    auto active_session_history_entry = m_associated_document->navigable()->active_session_history_entry();
+    // 2. Set this's relevant global object's navigable's active session history entry's scroll restoration mode to the given value.
+    auto active_session_history_entry = this_relevant_global_object.navigable()->active_session_history_entry();
     switch (scroll_restoration) {
     case Bindings::ScrollRestoration::Auto:
         active_session_history_entry->set_scroll_restoration_mode(ScrollRestorationMode::Auto);

Libraries/LibWeb/HTML/History.h

@@ -20,7 +20,7 @@ class History final : public Bindings::PlatformObject {
     GC_DECLARE_ALLOCATOR(History);
 
 public:
-    [[nodiscard]] static GC::Ref<History> create(JS::Realm&, DOM::Document&);
+    [[nodiscard]] static GC::Ref<History> create(JS::Realm&);
 
     virtual ~History() override;
 
@@ -41,14 +41,14 @@ public:
     void set_state(JS::Value s) { m_state = s; }
 
 private:
-    History(JS::Realm&, DOM::Document&);
+    History(JS::Realm&);
 
     virtual void initialize(JS::Realm&) override;
     virtual void visit_edges(Cell::Visitor&) override;
+    WebIDL::ExceptionOr<void> delta_traverse(WebIDL::Long delta);
 
     WebIDL::ExceptionOr<void> shared_history_push_replace_state(JS::Value data, Optional<String> const& url, HistoryHandlingBehavior);
 
-    GC::Ref<DOM::Document> m_associated_document;
     JS::Value m_state { JS::js_null() };
 };