Fix IPv6Address#setShorts(), add ctype dependency

Author: DaveRandom

composer.json

@@ -4,7 +4,8 @@
     "license": "MIT",
     "keywords": ["dns"],
     "require": {
-        "php": ">=7.0"
+        "php": ">=7.0",
+        "ext-ctype": "*"
     },
     "autoload": {
         "psr-4": {

src/Records/Types/IPv4Address.php

@@ -81,7 +81,7 @@ public function setOctets(array $octets)
         }
 
         foreach ($octets as &$octet) {
-            if (\strspn((string)$octet, "0123456789") !== \strlen((string)$octet) || $octet < 0x00 || $octet > 0xff) {
+            if ((!\is_int($octet) && !\ctype_digit((string)$octet)) || $octet < 0x00 || $octet > 0xff) {
                 throw new \UnexpectedValueException('Octet list is not a valid IPv4 address: invalid octet value ' . $octet);
             }
 

src/Records/Types/IPv6Address.php

@@ -145,7 +145,7 @@ public function setShorts(array $shorts)
         }
 
         foreach ($shorts as &$short) {
-            if (\strspn((string)$short, "0123456789") !== \strlen($short) || $short < 0x0000 || $short > 0xffff) {
+            if ((!\is_int($short) && !\ctype_digit((string)$short)) || $short < 0x0000 || $short > 0xffff) {
                 throw new \UnexpectedValueException('Short list is not a valid IPv6 address: invalid short value ' . $short);
             }