From edf0aacda4452e0d0e656133b4af923d346fd78b Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Thu, 25 Jun 2020 22:23:33 +0200
Subject: [PATCH] LibWeb: Add Document.getElementsByTagName()

---
 Libraries/LibWeb/DOM/Document.cpp | 11 +++++++++++
 Libraries/LibWeb/DOM/Document.h   |  1 +
 Libraries/LibWeb/DOM/Document.idl |  1 +
 3 files changed, 13 insertions(+)

diff --git a/Libraries/LibWeb/DOM/Document.cpp b/Libraries/LibWeb/DOM/Document.cpp
index e0c607d3da..4c9810f374 100644
--- a/Libraries/LibWeb/DOM/Document.cpp
+++ b/Libraries/LibWeb/DOM/Document.cpp
@@ -333,6 +333,17 @@ Vector<const Element*> Document::get_elements_by_name(const String& name) const
     return elements;
 }
 
+NonnullRefPtrVector<Element> Document::get_elements_by_tag_name(const String& tag_name) const
+{
+    NonnullRefPtrVector<Element> elements;
+    for_each_in_subtree_of_type<Element>([&](auto& element) {
+        if (element.tag_name() == tag_name)
+            elements.append(element);
+        return IterationDecision::Continue;
+    });
+    return elements;
+}
+
 RefPtr<Element> Document::query_selector(const StringView& selector_text)
 {
     auto selector = parse_selector(selector_text);
diff --git a/Libraries/LibWeb/DOM/Document.h b/Libraries/LibWeb/DOM/Document.h
index d106d2d6fb..ff03cd1329 100644
--- a/Libraries/LibWeb/DOM/Document.h
+++ b/Libraries/LibWeb/DOM/Document.h
@@ -118,6 +118,7 @@ public:
     void schedule_style_update();
 
     Vector<const Element*> get_elements_by_name(const String&) const;
+    NonnullRefPtrVector<Element> get_elements_by_tag_name(const String&) const;
     RefPtr<Element> query_selector(const StringView&);
     NonnullRefPtrVector<Element> query_selector_all(const StringView&);
 
diff --git a/Libraries/LibWeb/DOM/Document.idl b/Libraries/LibWeb/DOM/Document.idl
index 59f032b216..1de360edcd 100644
--- a/Libraries/LibWeb/DOM/Document.idl
+++ b/Libraries/LibWeb/DOM/Document.idl
@@ -2,6 +2,7 @@ interface Document : Node {
 
     Element? getElementById(DOMString id);
     Element? querySelector(DOMString selectors);
+    ArrayFromVector getElementsByTagName(DOMString tagName);
     ArrayFromVector querySelectorAll(DOMString selectors);
     Element createElement(DOMString tagName);