LibWeb: Make HTMLCollection faster when it only cares about children

Some of the live HTMLCollection only ever contain children of their root
node. When we know that's the case, we can avoid doing a full subtree
traversal of all descendants and only visit children.

This cuts the ECMA262 spec loading time by over 10 seconds. :^)

1 files changed, 11 insertions, 11 deletions

diff --git a/Userland/Libraries/LibWeb/DOM/Document.cpp b/Userland/Libraries/LibWeb/DOM/Document.cpp
index d2c5312f47..79964e8723 100644
--- a/Userland/Libraries/LibWeb/DOM/Document.cpp
+++ b/Userland/Libraries/LibWeb/DOM/Document.cpp
@@ -1054,7 +1054,7 @@ void Document::set_hovered_node(Node* node)
 
 JS::NonnullGCPtr<HTMLCollection> Document::get_elements_by_name(DeprecatedString const& name)
 {
-    return HTMLCollection::create(*this, [name](Element const& element) {
+    return HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [name](Element const& element) {
         return element.name() == name;
     }).release_value_but_fixme_should_propagate_errors();
 }
@@ -1065,7 +1065,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::get_elements_by_class_name(Deprecated
     for (auto& name : class_names.view().split_view(' ')) {
         list_of_class_names.append(FlyString::from_utf8(name).release_value_but_fixme_should_propagate_errors());
     }
-    return HTMLCollection::create(*this, [list_of_class_names = move(list_of_class_names), quirks_mode = document().in_quirks_mode()](Element const& element) {
+    return HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [list_of_class_names = move(list_of_class_names), quirks_mode = document().in_quirks_mode()](Element const& element) {
         for (auto& name : list_of_class_names) {
             if (!element.has_class(name, quirks_mode ? CaseSensitivity::CaseInsensitive : CaseSensitivity::CaseSensitive))
                 return false;
@@ -1078,7 +1078,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::get_elements_by_class_name(Deprecated
 JS::NonnullGCPtr<HTMLCollection> Document::applets()
 {
     if (!m_applets)
-        m_applets = HTMLCollection::create(*this, [](auto&) { return false; }).release_value_but_fixme_should_propagate_errors();
+        m_applets = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](auto&) { return false; }).release_value_but_fixme_should_propagate_errors();
     return *m_applets;
 }
 
@@ -1086,7 +1086,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::applets()
 JS::NonnullGCPtr<HTMLCollection> Document::anchors()
 {
     if (!m_anchors) {
-        m_anchors = HTMLCollection::create(*this, [](Element const& element) {
+        m_anchors = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const& element) {
             return is<HTML::HTMLAnchorElement>(element) && element.has_attribute(HTML::AttributeNames::name);
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -1097,7 +1097,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::anchors()
 JS::NonnullGCPtr<HTMLCollection> Document::images()
 {
     if (!m_images) {
-        m_images = HTMLCollection::create(*this, [](Element const& element) {
+        m_images = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const& element) {
             return is<HTML::HTMLImageElement>(element);
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -1108,7 +1108,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::images()
 JS::NonnullGCPtr<HTMLCollection> Document::embeds()
 {
     if (!m_embeds) {
-        m_embeds = HTMLCollection::create(*this, [](Element const& element) {
+        m_embeds = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const& element) {
             return is<HTML::HTMLEmbedElement>(element);
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -1125,7 +1125,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::plugins()
 JS::NonnullGCPtr<HTMLCollection> Document::links()
 {
     if (!m_links) {
-        m_links = HTMLCollection::create(*this, [](Element const& element) {
+        m_links = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const& element) {
             return (is<HTML::HTMLAnchorElement>(element) || is<HTML::HTMLAreaElement>(element)) && element.has_attribute(HTML::AttributeNames::href);
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -1136,7 +1136,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::links()
 JS::NonnullGCPtr<HTMLCollection> Document::forms()
 {
     if (!m_forms) {
-        m_forms = HTMLCollection::create(*this, [](Element const& element) {
+        m_forms = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const& element) {
             return is<HTML::HTMLFormElement>(element);
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -1147,7 +1147,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::forms()
 JS::NonnullGCPtr<HTMLCollection> Document::scripts()
 {
     if (!m_scripts) {
-        m_scripts = HTMLCollection::create(*this, [](Element const& element) {
+        m_scripts = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const& element) {
             return is<HTML::HTMLScriptElement>(element);
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -1158,7 +1158,7 @@ JS::NonnullGCPtr<HTMLCollection> Document::scripts()
 JS::NonnullGCPtr<HTMLCollection> Document::all()
 {
     if (!m_all) {
-        m_all = HTMLCollection::create(*this, [](Element const&) {
+        m_all = HTMLCollection::create(*this, HTMLCollection::Scope::Descendants, [](Element const&) {
             return true;
         }).release_value_but_fixme_should_propagate_errors();
     }
@@ -2092,7 +2092,7 @@ void Document::check_favicon_after_loading_link_resource()
     if (!head_element)
         return;
 
-    auto favicon_link_elements = HTMLCollection::create(*head_element, [](Element const& element) {
+    auto favicon_link_elements = HTMLCollection::create(*head_element, HTMLCollection::Scope::Descendants, [](Element const& element) {
         if (!is<HTML::HTMLLinkElement>(element))
             return false;