Fix labels length check (#278)

* Fix label length check

* Test label too long on single word hostname

.gitattributes

@@ -1,4 +1,7 @@
-/Tests export-ignore
 /documentation export-ignore
+/tests export-ignore
 /.* export-ignore
-/phpunit.xml.dist
+/phpunit.xml.dist export-ignore
+/psalm.xml export-ignore
+/psalm.baseline.xml export-ignore
+/README.md export-ignore

.github/FUNDING.yml

@@ -0,0 +1,3 @@
+# Thanks!
+
+github: [egulias]

.gitignore

@@ -1,4 +1,6 @@
+.phpunit.result.cache
 .idea
+.vscode
 composer.lock
 report/
 vendor/

.travis.yml

@@ -1,5 +1,4 @@
 language: php
-
 matrix:
   include:
     - php: 5.5.9
@@ -28,10 +27,33 @@ matrix:
       env:
         - psalm=yes
       dist: bionic
+#ppc64le support code
+    - php: 5.6
+      arch: ppc64le
+      env:
+      dist: xenial
+    - php: 7.0
+      arch: ppc64le
+      dist: xenial
+    - php: 7.1
+      arch: ppc64le
+      env:
+        - psalm=yes
+      dist: bionic
+    - php: 7.2
+      arch: ppc64le
+      env:
+        - psalm=yes
+      dist: bionic
+    - php: 7.4
+      arch: ppc64le
+      env:
+        - psalm=yes
+      dist: bionic
 
 install:
   - if [ "$deps" = "low" ]; then composer update --prefer-lowest; else composer install; fi
-  - if [ "$psalm" = "yes" ]; then composer require --dev vimeo/psalm; fi
+  - if [ "$psalm" = "yes" ]; then composer require --dev vimeo/psalm:3.18.2; fi
 
 before_script:
   - mkdir -p build/logs
@@ -42,3 +64,4 @@ script:
 
 after_script:
   - php vendor/bin/coveralls
+  

EmailValidator/Validation/DNSCheckValidation.php

@@ -1,77 +0,0 @@
-<?php
-
-namespace Egulias\EmailValidator\Validation;
-
-use Egulias\EmailValidator\EmailLexer;
-use Egulias\EmailValidator\Exception\InvalidEmail;
-use Egulias\EmailValidator\Warning\NoDNSMXRecord;
-use Egulias\EmailValidator\Exception\NoDNSRecord;
-
-class DNSCheckValidation implements EmailValidation
-{
-    /**
-     * @var array
-     */
-    private $warnings = [];
-
-    /**
-     * @var InvalidEmail|null
-     */
-    private $error;
-
-    public function __construct()
-    {
-        if (!function_exists('idn_to_ascii')) {
-            throw new \LogicException(sprintf('The %s class requires the Intl extension.', __CLASS__));
-        }
-    }
-
-    public function isValid($email, EmailLexer $emailLexer)
-    {
-        // use the input to check DNS if we cannot extract something similar to a domain
-        $host = $email;
-
-        // Arguable pattern to extract the domain. Not aiming to validate the domain nor the email
-        if (false !== $lastAtPos = strrpos($email, '@')) {
-            $host = substr($email, $lastAtPos + 1);
-        }
-
-        return $this->checkDNS($host);
-    }
-
-    public function getError()
-    {
-        return $this->error;
-    }
-
-    public function getWarnings()
-    {
-        return $this->warnings;
-    }
-
-    /**
-     * @param string $host
-     *
-     * @return bool
-     */
-    protected function checkDNS($host)
-    {
-        $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');
-
-        if (!$MXresult) {
-            $this->warnings[NoDNSMXRecord::CODE] = new NoDNSMXRecord();
-            $Aresult = checkdnsrr($host, 'A') || checkdnsrr($host, 'AAAA');
-            if (!$Aresult) {
-                $this->error = new NoDNSRecord();
-            }
-        }
-        return $MXresult || $Aresult;
-    }
-}

README.md

@@ -1,7 +1,12 @@
 # EmailValidator
-[![Build Status](https://travis-ci.org/egulias/EmailValidator.svg?branch=master)](https://travis-ci.org/egulias/EmailValidator) [![Coverage Status](https://coveralls.io/repos/egulias/EmailValidator/badge.svg?branch=master)](https://coveralls.io/r/egulias/EmailValidator?branch=master) [![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/egulias/EmailValidator/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/egulias/EmailValidator/?branch=master) [![SensioLabsInsight](https://insight.sensiolabs.com/projects/22ba6692-9c02-42e5-a65d-1c5696bfffc6/small.png)](https://insight.sensiolabs.com/projects/22ba6692-9c02-42e5-a65d-1c5696bfffc6)
-=============================
-## Suported RFCs ##
+
+[![Build Status](https://travis-ci.org/egulias/EmailValidator.svg?branch=master)](https://travis-ci.org/egulias/EmailValidator)
+[![Coverage Status](https://coveralls.io/repos/egulias/EmailValidator/badge.svg?branch=master)](https://coveralls.io/r/egulias/EmailValidator?branch=master)
+[![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/egulias/EmailValidator/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/egulias/EmailValidator/?branch=master)
+[![SensioLabsInsight](https://insight.sensiolabs.com/projects/22ba6692-9c02-42e5-a65d-1c5696bfffc6/small.png)](https://insight.sensiolabs.com/projects/22ba6692-9c02-42e5-a65d-1c5696bfffc6)
+
+## Supported RFCs ##
+
 This library aims to support:
 
 RFC 5321, 5322, 6530, 6531, 6532.
@@ -9,7 +14,7 @@ RFC 5321, 5322, 6530, 6531, 6532.
 ## Requirements ##
 
  * [Composer](https://getcomposer.org) is required for installation
- * [Spoofchecking](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/SpoofCheckValidation.php) and [DNSCheckValidation](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/DNSCheckValidation.php) validation requires that your PHP system has the [PHP Internationalization Libraries](https://php.net/manual/en/book.intl.php) (also known as PHP Intl)
+ * [Spoofchecking](/src/Validation/SpoofCheckValidation.php) and [DNSCheckValidation](/src/Validation/DNSCheckValidation.php) validation requires that your PHP system has the [PHP Internationalization Libraries](https://php.net/manual/en/book.intl.php) (also known as PHP Intl)
 
 ## Installation ##
 
@@ -20,6 +25,7 @@ composer require egulias/email-validator
 ```
 
 ## Getting Started ##
+
 `EmailValidator`requires you to decide which (or combination of them) validation/s strategy/ies you'd like to follow for each [validation](#available-validations).
 
 A basic example with the RFC validation
@@ -36,16 +42,14 @@ $validator->isValid("example@example.com", new RFCValidation()); //true
 
 ### Available validations ###
 
-1. [RFCValidation](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/RFCValidation.php)
-2. [NoRFCWarningsValidation](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/NoRFCWarningsValidation.php)
-3. [DNSCheckValidation](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/DNSCheckValidation.php)
-4. [SpoofCheckValidation](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/SpoofCheckValidation.php)
-5. [MultipleValidationWithAnd](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/MultipleValidationWithAnd.php)
-6. [Your own validation](#how-to-extend)
+1. [RFCValidation](/src/Validation/RFCValidation.php): Standard RFC-like email validation.
+2. [NoRFCWarningsValidation](/src/Validation/NoRFCWarningsValidation.php): RFC-like validation that will fail when warnings* are found.
+3. [DNSCheckValidation](/src/Validation/DNSCheckValidation.php): Will check if there are DNS records that signal that the server accepts emails. This does not entails that the email exists.
+4. [SpoofCheckValidation](/src/Validation/SpoofCheckValidation.php): Will check for multi-utf-8 chars that can signal an erroneous email name.
+5. [MultipleValidationWithAnd](/src/Validation/MultipleValidationWithAnd.php): It is a validation that operates over other validations performing a logical and (&&) over the result of each validation.
+6. [Your own validation](#how-to-extend): You can extend the library behaviour by implementing your own validations.
 
-`MultipleValidationWithAnd`
-
-It is a validation that operates over other validations performing a logical and (&&) over the result of each validation.
+*warnings: Warnings are deviations from the RFC that in a broader interpretation are acceptded.
 
 ```php
 <?php
@@ -60,15 +64,17 @@ $multipleValidations = new MultipleValidationWithAnd([
     new RFCValidation(),
     new DNSCheckValidation()
 ]);
-$validator->isValid("example@example.com", $multipleValidations); //true
+//ietf.org has MX records signaling a server with email capabilites
+$validator->isValid("example@ietf.org", $multipleValidations); //true
 ```
 
 ### How to extend ###
 
-It's easy! You just need to implement [EmailValidation](https://github.com/egulias/EmailValidator/blob/master/EmailValidator/Validation/EmailValidation.php) and you can use your own validation.
+It's easy! You just need to implement [EmailValidation](/src/Validation/EmailValidation.php) and you can use your own validation.
 
 
 ## Other Contributors ##
+
 (You can find current contributors [here](https://github.com/egulias/EmailValidator/graphs/contributors))
 
 As this is a port from another library and work, here are other people related to the previous one:
@@ -78,5 +84,5 @@ As this is a port from another library and work, here are other people related t
 * Dominic Sayers [@dominicsayers](https://github.com/dominicsayers):  	The original isemail function
 
 ## License ##
-Released under the MIT License attached with this code.
 
+Released under the MIT License attached with this code.

Tests/EmailValidator/Validation/DNSCheckValidationTest.php

@@ -1,63 +0,0 @@
-<?php
-
-namespace Egulias\Tests\EmailValidator\Validation;
-
-use Egulias\EmailValidator\EmailLexer;
-use Egulias\EmailValidator\Exception\NoDNSRecord;
-use Egulias\EmailValidator\Validation\DNSCheckValidation;
-use Egulias\EmailValidator\Warning\NoDNSMXRecord;
-use PHPUnit\Framework\TestCase;
-
-class DNSCheckValidationTest extends TestCase
-{
-    public function validEmailsProvider()
-    {
-        return [
-            // dot-atom
-            ['Abc@example.com'],
-            ['ABC@EXAMPLE.COM'],
-            ['Abc.123@example.com'],
-            ['user+mailbox/department=shipping@example.com'],
-            ['!#$%&\'*+-/=?^_`.{|}~@example.com'],
-
-            // quoted string
-            ['"Abc@def"@example.com'],
-            ['"Fred\ Bloggs"@example.com'],
-            ['"Joe.\\Blow"@example.com'],
-            
-            // unicide
-            ['ñandu.cl'],
-        ];
-    }
-
-    /**
-     * @dataProvider validEmailsProvider
-     */
-    public function testValidDNS($validEmail)
-    {
-        $validation = new DNSCheckValidation();
-        $this->assertTrue($validation->isValid($validEmail, new EmailLexer()));
-    }
-
-    public function testInvalidDNS()
-    {
-        $validation = new DNSCheckValidation();
-        $this->assertFalse($validation->isValid("example@invalid.example.com", new EmailLexer()));
-    }
-
-    public function testDNSWarnings()
-    {
-        $validation = new DNSCheckValidation();
-        $expectedWarnings = [NoDNSMXRecord::CODE => new NoDNSMXRecord()];
-        $validation->isValid("example@invalid.example.com", new EmailLexer());
-        $this->assertEquals($expectedWarnings, $validation->getWarnings());
-    }
-
-    public function testNoDNSError()
-    {
-        $validation = new DNSCheckValidation();
-        $expectedError = new NoDNSRecord();
-        $validation->isValid("example@invalid.example.com", new EmailLexer());
-        $this->assertEquals($expectedError, $validation->getError());
-    }
-}

composer.json

@@ -18,21 +18,21 @@
     "symfony/polyfill-intl-idn": "^1.10"
   },
   "require-dev": {
-    "satooshi/php-coveralls": "^1.0.1",
+    "dominicsayers/isemail": "^3.0.7",
     "phpunit/phpunit": "^4.8.36|^7.5.15",
-    "dominicsayers/isemail": "^3.0.7"
+    "satooshi/php-coveralls": "^1.0.1"
   },
   "suggest": {
     "ext-intl": "PHP Internationalization Libraries are required to use the SpoofChecking validation"
   },
   "autoload": {
     "psr-4": {
-      "Egulias\\EmailValidator\\": "EmailValidator"
+      "Egulias\\EmailValidator\\": "src"
     }
   },
   "autoload-dev": {
     "psr-4": {
-      "Egulias\\Tests\\": "Tests"
+      "Egulias\\EmailValidator\\Tests\\": "tests"
     }
   }
 }

phpunit.xml.dist

@@ -12,14 +12,14 @@
 >
 <testsuites>
   <testsuite name="EmailValidator Test Suite">
-    <directory>./Tests/EmailValidator</directory>
+    <directory>./tests/EmailValidator</directory>
     <exclude>./vendor/</exclude>
   </testsuite>
 </testsuites>
 
 <filter>
   <whitelist>
-    <directory>./EmailValidator/</directory>
+    <directory>./src/</directory>
   </whitelist>
 </filter>
 </phpunit>

psalm.baseline.xml

@@ -1,16 +1,16 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <files psalm-version="3.8.3@389af1bfc739bfdff3f9e3dc7bd6499aee51a831">
-  <file src="EmailValidator/EmailLexer.php">
+  <file src="src/EmailLexer.php">
     <DocblockTypeContradiction occurrences="1">
       <code>self::$nullToken</code>
     </DocblockTypeContradiction>
   </file>
-  <file src="EmailValidator/Parser/Parser.php">
+  <file src="src/Parser/Parser.php">
     <MissingReturnType occurrences="1">
       <code>parse</code>
     </MissingReturnType>
   </file>
-  <file src="EmailValidator/Validation/SpoofCheckValidation.php">
+  <file src="src/Validation/SpoofCheckValidation.php">
     <UndefinedClass occurrences="2">
       <code>Spoofchecker</code>
       <code>Spoofchecker</code>

psalm.xml

@@ -8,7 +8,7 @@
     errorBaseline="./psalm.baseline.xml"
 >
     <projectFiles>
-        <directory name="EmailValidator" />
+        <directory name="src" />
         <ignoreFiles>
             <directory name="vendor" />
         </ignoreFiles>

src/EmailLexer.php

@@ -13,6 +13,8 @@ class EmailLexer extends AbstractLexer
     const S_BACKSLASH        = 92;
     const S_DOT              = 46;
     const S_DQUOTE           = 34;
+    const S_SQUOTE           = 39;
+    const S_BACKTICK         = 96;
     const S_OPENPARENTHESIS  = 49;
     const S_CLOSEPARENTHESIS = 261;
     const S_OPENBRACKET      = 262;
@@ -58,6 +60,8 @@ class EmailLexer extends AbstractLexer
         '/'    => self::S_SLASH,
         ','    => self::S_COMMA,
         '.'    => self::S_DOT,
+        "'"    => self::S_SQUOTE,
+        "`"    => self::S_BACKTICK,
         '"'    => self::S_DQUOTE,
         '-'    => self::S_HYPHEN,
         '::'   => self::S_DOUBLECOLON,

src/Exception/DomainAcceptsNoMail.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Egulias\EmailValidator\Exception;
+
+class DomainAcceptsNoMail extends InvalidEmail
+{
+    const CODE = 154;
+    const REASON = 'Domain accepts no mail (Null MX, RFC7505)';
+}

src/Exception/LocalOrReservedDomain.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Egulias\EmailValidator\Exception;
+
+class LocalOrReservedDomain extends InvalidEmail
+{
+    const CODE = 153;
+    const REASON = 'Local, mDNS or reserved domain (RFC2606, RFC6762)';
+}

src/Exception/UnclosedComment.php

@@ -5,5 +5,5 @@ namespace Egulias\EmailValidator\Exception;
 class UnclosedComment extends InvalidEmail
 {
     const CODE = 146;
-    const REASON = "No colosing comment token found";
+    const REASON = "No closing comment token found";
 }

src/Parser/DomainPart.php

@@ -35,6 +35,7 @@ use Egulias\EmailValidator\Warning\TLD;
 class DomainPart extends Parser
 {
     const DOMAIN_MAX_LENGTH = 254;
+    const LABEL_MAX_LENGTH = 63;
 
     /**
      * @var string
@@ -160,6 +161,7 @@ class DomainPart extends Parser
     protected function doParseDomainPart()
     {
         $domain = '';
+        $label = '';
         $openedParenthesis = 0;
         do {
             $prev = $this->lexer->getPrevious();
@@ -190,7 +192,12 @@ class DomainPart extends Parser
                 $this->parseDomainLiteral();
             }
 
-            $this->checkLabelLength($prev);
+            if ($this->lexer->token['type'] === EmailLexer::S_DOT) {
+                $this->checkLabelLength($label);
+                $label = '';
+            } else {
+                $label .= $this->lexer->token['value'];
+            }
 
             if ($this->isFWS()) {
                 $this->parseFWS();
@@ -198,8 +205,13 @@ class DomainPart extends Parser
 
             $domain .= $this->lexer->token['value'];
             $this->lexer->moveNext();
+            if ($this->lexer->token['type'] === EmailLexer::S_SP) {
+                throw new CharNotAllowed();
+            }
         } while (null !== $this->lexer->token['type']);
 
+        $this->checkLabelLength($label);
+
         return $domain;
     }
 
@@ -332,6 +344,8 @@ class DomainPart extends Parser
     {
         $invalidDomainTokens = array(
             EmailLexer::S_DQUOTE => true,
+            EmailLexer::S_SQUOTE => true,
+            EmailLexer::S_BACKTICK => true,
             EmailLexer::S_SEMICOLON => true,
             EmailLexer::S_GREATERTHAN => true,
             EmailLexer::S_LOWERTHAN => true,
@@ -381,16 +395,31 @@ class DomainPart extends Parser
         return true;
     }
 
-    protected function checkLabelLength(array $prev)
+    /**
+     * @param string $label
+     */
+    protected function checkLabelLength($label)
     {
-        if ($this->lexer->token['type'] === EmailLexer::S_DOT &&
-            $prev['type'] === EmailLexer::GENERIC &&
-            strlen($prev['value']) > 63
-        ) {
+        if ($this->isLabelTooLong($label)) {
             $this->warnings[LabelTooLong::CODE] = new LabelTooLong();
         }
     }
 
+    /**
+     * @param string $label
+     * @return bool
+     */
+    private function isLabelTooLong($label)
+    {
+        if (preg_match('/[^\x00-\x7F]/', $label)) {
+            idn_to_ascii($label, IDNA_DEFAULT, INTL_IDNA_VARIANT_UTS46, $idnaInfo);
+
+            return (bool) ($idnaInfo['errors'] & IDNA_ERROR_LABEL_TOO_LONG);
+        }
+
+        return strlen($label) > self::LABEL_MAX_LENGTH;
+    }
+
     protected function parseDomainComments()
     {
         $this->isUnclosedComment();

src/Parser/Parser.php

@@ -22,7 +22,7 @@ use Egulias\EmailValidator\Warning\QuotedString;
 abstract class Parser
 {
     /**
-     * @var \Egulias\EmailValidator\Warning\Warning[]
+     * @var array
      */
     protected $warnings = [];
 

src/Validation/DNSCheckValidation.php

@@ -0,0 +1,166 @@
+<?php
+
+namespace Egulias\EmailValidator\Validation;
+
+use Egulias\EmailValidator\EmailLexer;
+use Egulias\EmailValidator\Exception\InvalidEmail;
+use Egulias\EmailValidator\Exception\LocalOrReservedDomain;
+use Egulias\EmailValidator\Exception\DomainAcceptsNoMail;
+use Egulias\EmailValidator\Warning\NoDNSMXRecord;
+use Egulias\EmailValidator\Exception\NoDNSRecord;
+
+class DNSCheckValidation implements EmailValidation
+{
+    /**
+     * @var array
+     */
+    private $warnings = [];
+
+    /**
+     * @var InvalidEmail|null
+     */
+    private $error;
+
+    /**
+     * @var array
+     */
+    private $mxRecords = [];
+
+
+    public function __construct()
+    {
+        if (!function_exists('idn_to_ascii')) {
+            throw new \LogicException(sprintf('The %s class requires the Intl extension.', __CLASS__));
+        }
+    }
+
+    public function isValid($email, EmailLexer $emailLexer)
+    {
+        // use the input to check DNS if we cannot extract something similar to a domain
+        $host = $email;
+
+        // Arguable pattern to extract the domain. Not aiming to validate the domain nor the email
+        if (false !== $lastAtPos = strrpos($email, '@')) {
+            $host = substr($email, $lastAtPos + 1);
+        }
+
+        // Get the domain parts
+        $hostParts = explode('.', $host);
+
+        // Reserved Top Level DNS Names (https://tools.ietf.org/html/rfc2606#section-2),
+        // mDNS and private DNS Namespaces (https://tools.ietf.org/html/rfc6762#appendix-G)
+        $reservedTopLevelDnsNames = [
+            // Reserved Top Level DNS Names
+            'test',
+            'example',
+            'invalid',
+            'localhost',
+
+            // mDNS
+            'local',
+
+            // Private DNS Namespaces
+            'intranet',
+            'internal',
+            'private',
+            'corp',
+            'home',
+            'lan',
+        ];
+
+        $isLocalDomain = count($hostParts) <= 1;
+        $isReservedTopLevel = in_array($hostParts[(count($hostParts) - 1)], $reservedTopLevelDnsNames, true);
+
+        // Exclude reserved top level DNS names
+        if ($isLocalDomain || $isReservedTopLevel) {
+            $this->error = new LocalOrReservedDomain();
+            return false;
+        }
+
+        return $this->checkDns($host);
+    }
+
+    public function getError()
+    {
+        return $this->error;
+    }
+
+    public function getWarnings()
+    {
+        return $this->warnings;
+    }
+
+    /**
+     * @param string $host
+     *
+     * @return bool
+     */
+    protected function checkDns($host)
+    {
+        $variant = INTL_IDNA_VARIANT_UTS46;
+
+        $host = rtrim(idn_to_ascii($host, IDNA_DEFAULT, $variant), '.') . '.';
+
+        return $this->validateDnsRecords($host);
+    }
+
+
+    /**
+     * Validate the DNS records for given host.
+     *
+     * @param string $host A set of DNS records in the format returned by dns_get_record.
+     *
+     * @return bool True on success.
+     */
+    private function validateDnsRecords($host)
+    {
+        // Get all MX, A and AAAA DNS records for host
+        // Using @ as workaround to fix https://bugs.php.net/bug.php?id=73149
+        $dnsRecords = @dns_get_record($host, DNS_MX + DNS_A + DNS_AAAA);
+
+
+        // No MX, A or AAAA DNS records
+        if (empty($dnsRecords)) {
+            $this->error = new NoDNSRecord();
+            return false;
+        }
+
+        // For each DNS record
+        foreach ($dnsRecords as $dnsRecord) {
+            if (!$this->validateMXRecord($dnsRecord)) {
+                return false;
+            }
+        }
+
+        // No MX records (fallback to A or AAAA records)
+        if (empty($this->mxRecords)) {
+            $this->warnings[NoDNSMXRecord::CODE] = new NoDNSMXRecord();
+        }
+
+        return true;
+    }
+
+    /**
+     * Validate an MX record
+     *
+     * @param array $dnsRecord Given DNS record.
+     *
+     * @return bool True if valid.
+     */
+    private function validateMxRecord($dnsRecord)
+    {
+        if ($dnsRecord['type'] !== 'MX') {
+            return true;
+        }
+
+        // "Null MX" record indicates the domain accepts no mail (https://tools.ietf.org/html/rfc7505)
+        if (empty($dnsRecord['target']) || $dnsRecord['target'] === '.') {
+            $this->error = new DomainAcceptsNoMail();
+            return false;
+        }
+
+        $this->mxRecords[] = $dnsRecord;
+
+        return true;
+    }
+}

src/Warning/Warning.php

@@ -29,7 +29,7 @@ abstract class Warning
      */
     public function code()
     {
-        return self::CODE;
+        return static::CODE;
     }
 
     /**

tests/EmailValidator/EmailLexerTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator;
+namespace Egulias\EmailValidator\Tests\EmailValidator;
 
 use Egulias\EmailValidator\EmailLexer;
 use PHPUnit\Framework\TestCase;
@@ -138,6 +138,8 @@ class EmailLexerTests extends TestCase
             array(":", EmailLexer::S_COLON),
             array(".", EmailLexer::S_DOT),
             array("\"", EmailLexer::S_DQUOTE),
+            array("'", EmailLexer::S_SQUOTE),
+            array("`", EmailLexer::S_BACKTICK),
             array("-", EmailLexer::S_HYPHEN),
             array("\\", EmailLexer::S_BACKSLASH),
             array("/", EmailLexer::S_SLASH),

tests/EmailValidator/EmailValidatorTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator;
+namespace Egulias\EmailValidator\Tests\EmailValidator;
 
 use Egulias\EmailValidator\EmailValidator;
 use Egulias\EmailValidator\Validation\EmailValidation;

tests/EmailValidator/Validation/DNSCheckValidationTest.php

@@ -0,0 +1,109 @@
+<?php
+
+namespace Egulias\EmailValidator\Tests\EmailValidator\Validation;
+
+use Egulias\EmailValidator\EmailLexer;
+use Egulias\EmailValidator\Exception\NoDNSRecord;
+use Egulias\EmailValidator\Exception\LocalOrReservedDomain;
+use Egulias\EmailValidator\Exception\DomainAcceptsNoMail;
+use Egulias\EmailValidator\Validation\DNSCheckValidation;
+use Egulias\EmailValidator\Warning\NoDNSMXRecord;
+use PHPUnit\Framework\TestCase;
+
+class DNSCheckValidationTest extends TestCase
+{
+    public function validEmailsProvider()
+    {
+        return [
+            // dot-atom
+            ['Abc@ietf.org'],
+            ['ABC@ietf.org'],
+            ['Abc.123@ietf.org'],
+            ['user+mailbox/department=shipping@ietf.org'],
+            ['!#$%&\'*+-/=?^_`.{|}~@ietf.org'],
+
+            // quoted string
+            ['"Abc@def"@ietf.org'],
+            ['"Fred\ Bloggs"@ietf.org'],
+            ['"Joe.\\Blow"@ietf.org'],
+
+            // unicode
+            ['ñandu.cl'],
+        ];
+    }
+
+    public function localOrReservedEmailsProvider()
+    {
+        return [
+            // Reserved Top Level DNS Names
+            ['test'],
+            ['example'],
+            ['invalid'],
+            ['localhost'],
+
+            // mDNS
+            ['local'],
+
+            // Private DNS Namespaces
+            ['intranet'],
+            ['internal'],
+            ['private'],
+            ['corp'],
+            ['home'],
+            ['lan'],
+        ];
+    }
+
+    /**
+     * @dataProvider validEmailsProvider
+     */
+    public function testValidDNS($validEmail)
+    {
+        $validation = new DNSCheckValidation();
+        $this->assertTrue($validation->isValid($validEmail, new EmailLexer()));
+    }
+
+    public function testInvalidDNS()
+    {
+        $validation = new DNSCheckValidation();
+        $this->assertFalse($validation->isValid("example@invalid.example.com", new EmailLexer()));
+    }
+
+    /**
+     * @dataProvider localOrReservedEmailsProvider
+     */
+    public function testLocalOrReservedDomainError($localOrReservedEmails)
+    {
+        $validation = new DNSCheckValidation();
+        $expectedError = new LocalOrReservedDomain();
+        $validation->isValid($localOrReservedEmails, new EmailLexer());
+        $this->assertEquals($expectedError, $validation->getError());
+    }
+
+    public function testDomainAcceptsNoMailError()
+    {
+        $validation = new DNSCheckValidation();
+        $expectedError = new DomainAcceptsNoMail();
+        $isValidResult = $validation->isValid("nullmx@example.com", new EmailLexer());
+        $this->assertEquals($expectedError, $validation->getError());
+        $this->assertFalse($isValidResult);
+    }
+
+    /*
+    public function testDNSWarnings()
+    {
+        $validation = new DNSCheckValidation();
+        $expectedWarnings = [NoDNSMXRecord::CODE => new NoDNSMXRecord()];
+        $validation->isValid("example@invalid.example.com", new EmailLexer());
+        $this->assertEquals($expectedWarnings, $validation->getWarnings());
+    }
+    */
+
+    public function testNoDNSError()
+    {
+        $validation = new DNSCheckValidation();
+        $expectedError = new NoDNSRecord();
+        $validation->isValid("example@invalid.example.com", new EmailLexer());
+        $this->assertEquals($expectedError, $validation->getError());
+    }
+}

tests/EmailValidator/Validation/IsEmailFunctionTests.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator\Validation;
+namespace Egulias\EmailValidator\Tests\EmailValidator\Validation;
 
 use Egulias\EmailValidator\EmailValidator;
 use Egulias\EmailValidator\Validation\DNSCheckValidation;
@@ -27,7 +27,7 @@ class IsEmailFunctionTests extends TestCase
 
     public function isEmailTestSuite()
     {
-        $testSuite = dirname(__FILE__) . '/../../resources/is_email_tests.xml';
+        $testSuite = __DIR__ . '/../../resources/is_email_tests.xml';
         $document = new \DOMDocument();
         $document->load($testSuite);
         $elements = $document->getElementsByTagName('test');

tests/EmailValidator/Validation/MultipleValidationWithAndTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator\Validation;
+namespace Egulias\EmailValidator\Tests\EmailValidator\Validation;
 
 use Egulias\EmailValidator\EmailLexer;
 use Egulias\EmailValidator\Exception\CommaInDomain;
@@ -18,7 +18,7 @@ class MultipleValidationWithAndTest extends TestCase
     public function testUsesAndLogicalOperation()
     {
         $lexer = new EmailLexer();
-        $validationTrue = $this->getMockBuilder("Egulias\\EmailValidator\\Validation\\EmailValidation")->getMock();
+        $validationTrue = $this->getMockBuilder(EmailValidation::class)->getMock();
         $validationTrue->expects($this->any())->method("isValid")->willReturn(true);
         $validationTrue->expects($this->any())->method("getWarnings")->willReturn([]);
         $validationFalse = $this->getMockBuilder(EmailValidation::class)->getMock();
@@ -60,7 +60,7 @@ class MultipleValidationWithAndTest extends TestCase
         $expectedResult = array_merge($warnings1, $warnings2);
 
         $lexer = new EmailLexer();
-        $validation1 = $this->getMockBuilder("Egulias\\EmailValidator\\Validation\\EmailValidation")->getMock();
+        $validation1 = $this->getMockBuilder(EmailValidation::class)->getMock();
         $validation1->expects($this->any())->method("isValid")->willReturn(true);
         $validation1->expects($this->once())->method("getWarnings")->willReturn($warnings1);
 

tests/EmailValidator/Validation/NoRFCWarningsValidationTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator\Validation;
+namespace Egulias\EmailValidator\Tests\EmailValidator\Validation;
 
 use Egulias\EmailValidator\EmailLexer;
 use Egulias\EmailValidator\Exception\NoDomainPart;
@@ -26,11 +26,22 @@ class NoRFCWarningsValidationTest extends TestCase
         $this->assertInstanceOf(RFCWarnings::class, $validation->getError());
     }
 
-    public function testEmailWithoutWarningsIsValid()
+    /**
+     * @dataProvider getValidEmailsWithoutWarnings
+     */
+    public function testEmailWithoutWarningsIsValid($email)
     {
         $validation = new NoRFCWarningsValidation();
 
-        $this->assertTrue($validation->isValid('example@example.com', new EmailLexer()));
+        $this->assertTrue($validation->isValid($email, new EmailLexer()));
         $this->assertNull($validation->getError());
     }
+
+    public function getValidEmailsWithoutWarnings()
+    {
+        return [
+            ['example@example.com',],
+            [sprintf('example@%s.com', str_repeat('ъ', 40)),],
+        ];
+    }
 }

tests/EmailValidator/Validation/RFCValidationTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator\Validation;
+namespace Egulias\EmailValidator\Tests\EmailValidator\Validation;
 
 use Egulias\EmailValidator\EmailLexer;
 use Egulias\EmailValidator\Validation\RFCValidation;
@@ -24,6 +24,7 @@ use Egulias\EmailValidator\Warning\CFWSWithFWS;
 use Egulias\EmailValidator\Warning\Comment;
 use Egulias\EmailValidator\Warning\DomainLiteral;
 use Egulias\EmailValidator\Warning\DomainTooLong;
+use Egulias\EmailValidator\Warning\EmailTooLong;
 use Egulias\EmailValidator\Warning\IPV6BadChar;
 use Egulias\EmailValidator\Warning\IPV6ColonEnd;
 use Egulias\EmailValidator\Warning\IPV6ColonStart;
@@ -104,7 +105,7 @@ class RFCValidationTest extends TestCase
 
     public function testInvalidUTF8Email()
     {
-        $email     = "\x80\x81\x82@\x83\x84\x85.\x86\x87\x88";
+        $email = "\x80\x81\x82@\x83\x84\x85.\x86\x87\x88";
         $this->assertFalse($this->validator->isValid($email, $this->lexer));
     }
 
@@ -167,6 +168,9 @@ class RFCValidationTest extends TestCase
             ['test@email<'],
             ['test@email{'],
             ['test@ '],
+            ['test@example.com []'],
+            ["test@example.com'"],
+            ["test@exam`ple.com"],
         ];
     }
 
@@ -211,6 +215,7 @@ class RFCValidationTest extends TestCase
             [new CRNoLF(), "example@exa\rmple.co.uk"],
             [new CRNoLF(), "example@[\r]"],
             [new CRNoLF(), "exam\rple@example.co.uk"],
+            [new ExpectingATEXT(), "test@example.com'"],
         ];
     }
 
@@ -222,12 +227,12 @@ class RFCValidationTest extends TestCase
         $this->assertTrue($this->validator->isValid($email, $this->lexer));
         $warnings = $this->validator->getWarnings();
         $this->assertCount(
-            count($warnings), $expectedWarnings,
+            count($expectedWarnings), $warnings,
             "Expected: " . implode(",", $expectedWarnings) . " and got " . implode(",", $warnings)
         );
 
         foreach ($warnings as $warning) {
-            $this->assertArrayHasKey($warning->code(), $expectedWarnings);
+            $this->assertContains($warning->code(), $expectedWarnings);
         }
     }
 
@@ -274,17 +279,29 @@ class RFCValidationTest extends TestCase
                 'example@toolonglocalparttoolonglocalparttoolonglocalparttoolonglocalpart.co.uk'
             ],
             [
-                [DomainTooLong::CODE, LabelTooLong::CODE,],
+                [DomainTooLong::CODE, LabelTooLong::CODE, EmailTooLong::CODE],
                 'example2@toolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocal'.
                 'parttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalpart'.
                 'toolonglocalparttoolonglocalparttoolonglocalparttoolonglocalpart'
             ],
             [
-                [DomainTooLong::CODE, LabelTooLong::CODE,],
+                [DomainTooLong::CODE, LabelTooLong::CODE, EmailTooLong::CODE],
                 'example@toolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocal'.
                 'parttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalparttoolonglocalpart'.
                 'toolonglocalparttoolonglocalparttoolonglocalparttoolonglocalpar'
             ],
+            [
+                [LabelTooLong::CODE,],
+                sprintf('example@%s.com', str_repeat('ъ', 60)),
+            ],
+            [
+                [LabelTooLong::CODE,],
+                sprintf('example@%s.com', str_repeat('a4t', 22)),
+            ],
+            [
+                [LabelTooLong::CODE,],
+                sprintf('example@%s', str_repeat('a4t', 22)),
+            ],
         ];
     }
 }

tests/EmailValidator/Validation/SpoofCheckValidationTest.php

@@ -1,6 +1,6 @@
 <?php
 
-namespace Egulias\Tests\EmailValidator\Validation;
+namespace Egulias\EmailValidator\Tests\EmailValidator\Validation;
 
 use Egulias\EmailValidator\EmailLexer;
 use Egulias\EmailValidator\Validation\SpoofCheckValidation;