Selector: Implement the `uniqueSort` chainable method

Some APIs, like `.prevAll()`, return elements in the reversed order, causing
confusing behavior when used with wrapping methods (see gh-5149 for more info)
 To provide an easy workaround, this commit implements a chainable `uniqueSort`
method on jQuery objects, an equivalent of `jQuery.uniqueSort`.

Fixes gh-5166
Closes gh-5168

1 files changed, 5 insertions, 0 deletions

diff --git a/src/selector/uniqueSort.js b/src/selector/uniqueSort.js
index e9438485c..91c7193e9 100644
--- a/src/selector/uniqueSort.js
+++ b/src/selector/uniqueSort.js
@@ -2,6 +2,7 @@ import jQuery from "../core.js";
 import document from "../var/document.js";
 import sort from "../var/sort.js";
 import splice from "../var/splice.js";
+import slice from "../var/slice.js";
 
 var hasDuplicate;
 
@@ -87,3 +88,7 @@ jQuery.uniqueSort = function( results ) {
 
 	return results;
 };
+
+jQuery.fn.uniqueSort = function() {
+	return this.pushStack( jQuery.uniqueSort( slice.apply( this ) ) );
+};