Deprecation: #103965 - Deprecate namespaced shorthand validator usage in Extbase 

Description 

It is possible to use undocumented namespaced shorthand notation in Extbase to add validators to properties or arguments. For example, TYPO3.CMS.Extbase:NotEmpty will be resolved as \TYPO3\CMS\Extbase\Validation\Validator\NotEmptyValidator and Vendor.Extension:Custom will be resolved as \Vendor\MyExtension\Validation\Validator\CustomValidator.

The namespaced shorthand notation for Extbase validators has been marked as deprecated and will be removed in TYPO3 v14.

Impact 

Using namespaced shorthand notation in Extbase will trigger a PHP deprecation warning.

Affected installations 

All installations using namespaced shorthand notation in Extbase.

Migration 

Extensions using the namespaced shorthand notation must use the FQCN of the validator instead. For Extbase core validators, the well known shorthand validator name can be used.

/**
 * @Extbase\Validate("TYPO3.CMS.Extbase:NotEmpty")
 */
protected $myProperty1;

/**
 * @Extbase\Validate("Vendor.Extension:Custom")
 */
protected $myProperty2;

/**
 * @Extbase\Validate("NotEmpty")
 */
protected $myProperty1;

/**
 * @Extbase\Validate("Vendor\Extension\Validation\Validator\CustomValidator")
 */
protected $myProperty2;

#[Extbase\Validate(['validator' => \TYPO3\CMS\Extbase\Validation\Validator\NotEmptyValidator::class])]
protected $myProperty1;

#[Extbase\Validate(['validator' => \Vendor\Extension\Validation\Validator\CustomValidator::class])]
protected $myProperty2;