Check for UPLOAD_ERR_NO_FILE in UploadedFile

fixes #4276, close #4358

framework/CHANGELOG.md

@@ -66,6 +66,7 @@ Yii Framework 2 Change Log
 - Bug #4127: `CaptchaValidator` clientside error message wasn't formed properly (samdark)
 - Bug #4162: Fixed bug where schema name was not used in ’SHOW CREATE TABLE’ query in `yii\db\mysql\Schema` (stevekr)
 - Bug #4241: `yii\widgets\Pjax` was incorrectly setting container id (mitalcoi)
+- Bug #4276: Added check for UPLOAD_ERR_NO_FILE in `yii\web\UploadedFile` and return null if no file was uploaded (OmgDef)
 - Bug: Fixed inconsistent return of `\yii\console\Application::runAction()` (samdark)
 - Bug: URL encoding for the route parameter added to `\yii\web\UrlManager` (klimov-paul)
 - Bug: Fixed the bug that requesting protected or private action methods would cause 500 error instead of 404 (qiangxue)
@@ -188,7 +189,7 @@ Yii Framework 2 Change Log
 - Chg: Added `prefix` column to `yii\log\DbTarget` to have the same amount of information logged as in files and emails (cebe)
 - Chg: Use `limit(null)` instead of `limit(-1)` in migration controller to be compatible to more backends (cebe)
 - New #3911: Added `yii\behaviors\SluggableBehavior` that fills the specified model attribute with the transliterated and adjusted version to use in URLs (creocoder)
-- New #4193: Added `yii\filters\Cors` CORS filter to allow Cross Origin Resource Sharing (pgaultier) 
+- New #4193: Added `yii\filters\Cors` CORS filter to allow Cross Origin Resource Sharing (pgaultier)
 
 
 2.0.0-beta April 13, 2014

framework/UPGRADE.md

@@ -145,4 +145,4 @@ new ones save the following code as `convert.php` that should be placed in the s
       ],
       // ...
   ];
-  ```
+  ```

framework/web/UploadedFile.php

@@ -223,7 +223,7 @@ class UploadedFile extends Object
             foreach ($names as $i => $name) {
                 self::loadFilesRecursive($key . '[' . $i . ']', $name, $tempNames[$i], $types[$i], $sizes[$i], $errors[$i]);
             }
-        } else {
+        } elseif ($errors !== UPLOAD_ERR_NO_FILE) {
             self::$_files[$key] = new static([
                 'name' => $names,
                 'tempName' => $tempNames,
@@ -233,4 +233,4 @@ class UploadedFile extends Object
             ]);
         }
     }
-}
+}