LibWeb: Implement HTMLTableSectionElement::insertRow()

Author: https://github.com/IdanHo
Commit: 009588eb28
Pull-request: https://github.com/SerenityOS/serenity/pull/13014
Reviewed-by: https://github.com/awesomekling ✅

Userland/Libraries/LibWeb/HTML/HTMLTableSectionElement.cpp

@@ -5,9 +5,11 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/DOM/ElementFactory.h>
 #include <LibWeb/DOM/HTMLCollection.h>
 #include <LibWeb/HTML/HTMLTableRowElement.h>
 #include <LibWeb/HTML/HTMLTableSectionElement.h>
+#include <LibWeb/Namespace.h>
 
 namespace Web::HTML {
 
@@ -33,4 +35,28 @@ NonnullRefPtr<DOM::HTMLCollection> HTMLTableSectionElement::rows() const
     });
 }
 
+// https://html.spec.whatwg.org/multipage/tables.html#dom-tbody-insertrow
+DOM::ExceptionOr<NonnullRefPtr<HTMLTableRowElement>> HTMLTableSectionElement::insert_row(long index)
+{
+    auto rows_collection = rows();
+    auto rows_collection_size = static_cast<long>(rows_collection->length());
+
+    // 1. If index is less than −1 or greater than the number of elements in the rows collection, throw an "IndexSizeError" DOMException.
+    if (index < -1 || index > rows_collection_size)
+        return DOM::IndexSizeError::create("Index is negative or greater than the number of rows");
+
+    // 2. Let table row be the result of creating an element given this element's node document, tr, and the HTML namespace.
+    auto table_row = static_ptr_cast<HTMLTableRowElement>(DOM::create_element(document(), TagNames::tr, Namespace::HTML));
+
+    // 3. If index is −1 or equal to the number of items in the rows collection, then append table row to this element.
+    if (index == -1 || index == rows_collection_size)
+        append_child(table_row);
+    // 4. Otherwise, insert table row as a child of this element, immediately before the index-th tr element in the rows collection.
+    else
+        table_row->insert_before(*this, rows_collection->item(index));
+
+    // 5. Return table row.
+    return table_row;
+}
+
 }