From 54859fabea8b3beecbb1a282888d5c990036b9e3 Mon Sep 17 00:00:00 2001
From: Tom Sommer <tomsommer@users.noreply.github.com>
Date: Thu, 16 Aug 2018 22:49:45 +0200
Subject: [PATCH] INTL_IDNA_VARIANT_UTS46 is not supported on all systems
 (#173)

* INTL_IDNA_VARIANT_UTS46 is not supported on all systems

Fall back to INTL_IDNA_VARIANT_2003 if INTL_IDNA_VARIANT_UTS46 is not found.

* Fix syntax error

* Update DNSCheckValidation.php
---
 EmailValidator/Validation/DNSCheckValidation.php | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/EmailValidator/Validation/DNSCheckValidation.php b/EmailValidator/Validation/DNSCheckValidation.php
index ec12958..e5c3e5d 100644
--- a/EmailValidator/Validation/DNSCheckValidation.php
+++ b/EmailValidator/Validation/DNSCheckValidation.php
@@ -51,7 +51,11 @@ public function getWarnings()
 
     protected function checkDNS($host)
     {
-        $host = rtrim(idn_to_ascii($host, IDNA_DEFAULT, INTL_IDNA_VARIANT_UTS46), '.') . '.';
+        $variant = INTL_IDNA_VARIANT_2003;
+        if ( defined('INTL_IDNA_VARIANT_UTS46') ) {
+            $variant = INTL_IDNA_VARIANT_UTS46;
+        }
+        $host = rtrim(idn_to_ascii($host, IDNA_DEFAULT, $variant), '.') . '.';
 
         $Aresult = true;
         $MXresult = checkdnsrr($host, 'MX');