getUploadFileError example

$data = [];
                $files = $event->getData();

                if (!\is_array($files)) {
                    $files = [];
                }

                foreach ($files as $file) {
                    if ($requestHandler->isFileUpload($file)) {
                        $data[] = $file;

                        if (method_exists($requestHandler, 'getUploadFileError') && null !== $errorCode = $requestHandler->getUploadFileError($file)) {
                            $form->addError($this->getFileUploadError($errorCode));
                        }
                    }
                }

                // Since the array is never considered empty in the view data format                 // on submission, we need to evaluate the configured empty data here                 if ([] === $data) {
                    $emptyData = $form->getConfig()->getEmptyData();
                    $data = $emptyData instanceof \Closure ? $emptyData($form, $data) : $emptyData;
                }

                

public function testInvalidFilesAreRejected()
    {
        $this->assertFalse($this->requestHandler->isFileUpload($this->getInvalidFile()));
    }

    /** * @dataProvider uploadFileErrorCodes */
    public function testFailedFileUploadIsTurnedIntoFormError($errorCode, $expectedErrorCode)
    {
        $this->assertSame($expectedErrorCode, $this->requestHandler->getUploadFileError($this->getFailedUploadedFile($errorCode)));
    }

    public static function uploadFileErrorCodes()
    {
        return [
            'no error' => [\UPLOAD_ERR_OK, null],
            'upload_max_filesize ini directive' => [\UPLOAD_ERR_INI_SIZE, \UPLOAD_ERR_INI_SIZE],
            'MAX_FILE_SIZE from form' => [\UPLOAD_ERR_FORM_SIZE, \UPLOAD_ERR_FORM_SIZE],
            'partially uploaded' => [\UPLOAD_ERR_PARTIAL, \UPLOAD_ERR_PARTIAL],
            'no file upload' => [\UPLOAD_ERR_NO_FILE, \UPLOAD_ERR_NO_FILE],
            'missing temporary directory' => [\UPLOAD_ERR_NO_TMP_DIR, \UPLOAD_ERR_NO_TMP_DIR],