Skip validation if file input does not exist (#13977)

Author: s1lver

framework/CHANGELOG.md

@@ -4,6 +4,7 @@ Yii Framework 2 Change Log
 2.0.16 under development
 ------------------------
 
+- Bug #13977: Skip validation if file input does not exist (RobinKamps, s1lver)
 - Bug #16183: Fixed when `yii\helpers\BaseFileHelper` sometimes returned wrong value (samdark, SilverFire, OndrejVasicek)
 - Bug #13932: Fix number validator attributes comparison (uaoleg, s1lver)
 - Bug #14039, #16636: Fixed validation for disabled inputs (s1lver, omzy83)

framework/assets/yii.validation.js

@@ -376,13 +376,15 @@ yii.validation = (function ($) {
             return [];
         }
 
-        // Continue validation if file input does not exist
+        var fileInput = $(attribute.input, attribute.$form).get(0);
+
+        // Skip validation if file input does not exist
         // (in case file inputs are added dynamically and no file input has been added to the form)
-        if (typeof $(attribute.input, attribute.$form).get(0) === "undefined") {
+        if (typeof fileInput === "undefined") {
             return [];
         }
 
-        var files = $(attribute.input, attribute.$form).get(0).files;
+        var files = fileInput.files;
         if (!files) {
             messages.push(options.message);
             return [];