Fixed a bug in the way jquery.init.js was being used.

src/dal/static/autocomplete_light/jquery.init.js

@@ -1,9 +1,20 @@
 var yl = yl || {};
+// Directly above this file, we included the jQuery provided by django. That
+// means it set itself to window.$ and window.jQuery, and stored away any
+// existing jQuery that may have been installed previously. Calling
+// jQuery.noConflict(true) will remove OUR copy of jQuery from the global
+// namespace and restore the original values of window.$ and window.jQuery.
+// This is necessary so that code which uses a version of jQuery that may
+// have been installed up-page gets the version it expects.
+yl.jQuery = jQuery.noConflict(true);
 
-if (yl.jQuery === undefined) {
-    /* If the user has included another copy of jQuery use that, even in the admin */
-    if (typeof $ !== 'undefined')
-        yl.jQuery = $;
-    else if ((typeof django !== 'undefined') && (typeof django.jQuery !== 'undefined'))
-        yl.jQuery = django.jQuery;
+// Here, we set up django.jQuery, instead of letting admin/js/jquery.init.js
+// do it. This is necessary because it ALSO calls jQuery.noConflict(true).
+// It we let it do that, it would break any code further down the page that
+// expects window.$ and window.jQuery to be defined.
+var django = django || {};
+if (typeof django.jQuery === 'undefined') {
+    // If django.jQuery is not yet defined, we need to define it so that
+    // admin/js/autocomplete.js (which we include with our widget) can run.
+    django.jQuery = yl.jQuery;
 }

src/dal_select2/widgets.py

@@ -46,7 +46,6 @@ def media(self):
                 'admin/js/vendor/jquery/jquery%s.js' % extra,
                 'admin/js/vendor/select2/select2.full%s.js' % extra,
             ) + i18n_file + (
-                'admin/js/jquery.init.js',
                 'autocomplete_light/jquery.init.js',
                 'autocomplete_light/autocomplete.init.js',
                 'admin/js/autocomplete.js',