Validators: fixed compatibility with latest nette/utils

Range can contain empty strings when reference to another form field is used: addRule($form::RANGE, NULL, [$form['min'], $form['max'])

Author: dg

src/Forms/Validator.php

@@ -152,6 +152,9 @@ public static function validateValid(Controls\BaseControl $control): bool
 	 */
 	public static function validateRange(IControl $control, array $range): bool
 	{
+		$range = array_map(function ($v) {
+			return $v === '' ? NULL : $v;
+		}, $range);
 		return Validators::isInRange($control->getValue(), $range);
 	}
 
@@ -161,7 +164,7 @@ public static function validateRange(IControl $control, array $range): bool
 	 */
 	public static function validateMin(IControl $control, $minimum): bool
 	{
-		return Validators::isInRange($control->getValue(), [$minimum, NULL]);
+		return Validators::isInRange($control->getValue(), [$minimum === '' ? NULL : $minimum, NULL]);
 	}
 
 
@@ -170,7 +173,7 @@ public static function validateMin(IControl $control, $minimum): bool
 	 */
 	public static function validateMax(IControl $control, $maximum): bool
 	{
-		return Validators::isInRange($control->getValue(), [NULL, $maximum]);
+		return Validators::isInRange($control->getValue(), [NULL, $maximum === '' ? NULL : $maximum]);
 	}