Move to project dropdown with infinite scroll for better performance

Use just SQL to check is a user can admin_issue on a project

Using offset pagination instead pages to avoid a count query

Tradeoff

- we duplicate how we check admin_issue in a SQL relation in the Ability class

1 files changed, 19 insertions, 5 deletions

diff --git a/app/assets/javascripts/issuable_form.js b/app/assets/javascripts/issuable_form.js
index 297d4f029f0..b7f92ae9883 100644
--- a/app/assets/javascripts/issuable_form.js
+++ b/app/assets/javascripts/issuable_form.js
@@ -102,20 +102,34 @@
     };
 
     IssuableForm.prototype.initMoveDropdown = function() {
-      var $moveDropdown;
+      var $moveDropdown, pageSize;
       $moveDropdown = $('.js-move-dropdown');
       if ($moveDropdown.length) {
+        pageSize = $moveDropdown.data('page-size');
         return $('.js-move-dropdown').select2({
           ajax: {
             url: $moveDropdown.data('projects-url'),
-            results: function(data) {
+            quietMillis: 125,
+            data: function(term, page, context) {
               return {
-                results: data
+                search: term,
+                offset_id: context
               };
             },
-            data: function(query) {
+            results: function(data) {
+              var context,
+                more;
+
+              if (data.length >= pageSize)
+                more = true;
+
+              if (data[data.length - 1])
+                context = data[data.length - 1].id;
+
               return {
-                search: query
+                results: data,
+                more: more,
+                context: context
               };
             }
           },