CSS: isHidden -> isHiddenWithinTree

Fixes gh-2404
Close gh-2855

1 files changed, 18 insertions, 0 deletions

diff --git a/src/css/var/isHiddenWithinTree.js b/src/css/var/isHiddenWithinTree.js
new file mode 100644
index 000000000..1c81f6480
--- /dev/null
+++ b/src/css/var/isHiddenWithinTree.js
@@ -0,0 +1,18 @@
+define( [
+	"../../core",
+	"../../selector"
+
+	// css is assumed
+], function( jQuery ) {
+
+	// This function differs from the :hidden selector
+	// in that it intentionally ignores hidden ancestors (gh-2404)
+	return function( elem, el ) {
+
+		// isHiddenWithinTree might be called from jQuery#filter function;
+		// in that case, element will be second argument
+		elem = el || elem;
+		return jQuery.css( elem, "display" ) === "none" ||
+			!jQuery.contains( elem.ownerDocument, elem );
+	};
+} );