From aea418392ab6cf2f3dfc519f12ef34f3f7516b4d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= <emilio@crisal.io>
Date: Wed, 17 Oct 2018 01:35:21 +0000
Subject: [PATCH] Bug 1499571 - HTMLOptionsCollection::Remove shouldn't remove
 the first element of the collection if out of bounds. r=bzbarsky

Make it just forward to HTMLSelectElement::Remove like other browsers.

Differential Revision: https://phabricator.services.mozilla.com/D8934
---
 dom/html/HTMLOptionsCollection.cpp                           | 5 -----
 dom/html/HTMLSelectElement.cpp                               | 4 ++++
 dom/html/test/test_bug405242.html                            | 4 ++--
 .../forms/the-select-element/select-remove.html.ini          | 4 ----
 4 files changed, 6 insertions(+), 11 deletions(-)
 delete mode 100644 testing/web-platform/meta/html/semantics/forms/the-select-element/select-remove.html.ini

diff --git a/dom/html/HTMLOptionsCollection.cpp b/dom/html/HTMLOptionsCollection.cpp
index 651c9f2dc657..21ea157161b5 100644
--- a/dom/html/HTMLOptionsCollection.cpp
+++ b/dom/html/HTMLOptionsCollection.cpp
@@ -285,11 +285,6 @@ HTMLOptionsCollection::Remove(int32_t aIndex, ErrorResult& aError)
     aError.Throw(NS_ERROR_UNEXPECTED);
     return;
   }
-
-  uint32_t len = mSelect->Length();
-  if (aIndex < 0 || (uint32_t)aIndex >= len)
-    aIndex = 0;
-
   mSelect->Remove(aIndex);
 }
 
diff --git a/dom/html/HTMLSelectElement.cpp b/dom/html/HTMLSelectElement.cpp
index 21f3835256b3..8f0e86d097df 100644
--- a/dom/html/HTMLSelectElement.cpp
+++ b/dom/html/HTMLSelectElement.cpp
@@ -600,6 +600,10 @@ HTMLSelectElement::Add(nsGenericHTMLElement& aElement,
 void
 HTMLSelectElement::Remove(int32_t aIndex)
 {
+  if (aIndex < 0) {
+    return;
+  }
+
   nsCOMPtr<nsINode> option = Item(static_cast<uint32_t>(aIndex));
   if (!option) {
     return;
diff --git a/dom/html/test/test_bug405242.html b/dom/html/test/test_bug405242.html
index 9ca3c11568ef..19c38c5de912 100644
--- a/dom/html/test/test_bug405242.html
+++ b/dom/html/test/test_bug405242.html
@@ -27,8 +27,8 @@ sel.appendChild(opt);
 sel.options.remove(0);
 sel.options.remove(1000);
 sel.options.remove(-1);
-is(sel.length, 1, "Unexpected option collection length");
-is(sel[0].value, "10", "Unexpected remained option");
+is(sel.length, 3, "Unexpected option collection length");
+is(sel[2].value, "10", "Unexpected remained option");
 </script>
 </pre>
 </body>
diff --git a/testing/web-platform/meta/html/semantics/forms/the-select-element/select-remove.html.ini b/testing/web-platform/meta/html/semantics/forms/the-select-element/select-remove.html.ini
deleted file mode 100644
index 083f9f14a525..000000000000
--- a/testing/web-platform/meta/html/semantics/forms/the-select-element/select-remove.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[select-remove.html]
-  [select.options.remove(n) should work]
-    expected: FAIL
-