Enable UTF-8 when checking string is single line (#54)

* Enable UTF-8 in checking single line because some multi-byte strings
contain a new line when interpreted as single byte

src/Address.php

@@ -31,7 +31,7 @@ final class Address
      */
     public function __construct(EmailAddress $address, string $name = '')
     {
-        if (\preg_match('/\v/', $name) !== 0) {
+        if (\preg_match('/\v/u', $name) !== 0) {
             throw new \InvalidArgumentException('Cannot use vertical white space within name of email address');
         }
 

src/EmailAddress.php

@@ -25,7 +25,7 @@ final class EmailAddress
      */
     public function __construct(string $address)
     {
-        if (\preg_match('/\v/', $address, $matches) !== 0) {
+        if (\preg_match('/\v/u', $address, $matches) !== 0) {
             throw new \InvalidArgumentException('Cannot use vertical white space within email address');
         }
 

src/Header/Subject.php

@@ -17,7 +17,7 @@ final class Subject implements HeaderInterface
      */
     public function __construct(string $subject)
     {
-        if (\preg_match('/\v/', $subject) !== 0) {
+        if (\preg_match('/\v/u', $subject) !== 0) {
             throw new \InvalidArgumentException('Cannot use vertical white space within subject');
         }
 

test/Unit/AddressTest.php

@@ -120,6 +120,15 @@ public function it_can_be_converted_to_readable_string()
         $this->assertEquals('local-part@münchen.com', $address->toReadableString());
     }
 
+    /**
+     * @test
+     */
+    public function it_can_be_constructed_with_a_multi_byte_name_leading_to_new_line_in_single_byte()
+    {
+        $address = new Address(new EmailAddress('[email protected]'), 'Миха');
+        $this->assertEquals('=?UTF-8?B?0JzQuNGF0LA=?= <[email protected]>', (string)$address);
+    }
+
     /**
      * @return array
      */

test/Unit/EmailAddressTest.php

@@ -48,6 +48,15 @@ public function provideAddresses()
         ];
     }
 
+    /**
+     * @test
+     */
+    public function it_can_be_constructed_with_a_multi_byte_name_leading_to_new_line_in_single_byte()
+    {
+        $address = new EmailAddress('Миха@domain.com');
+        $this->assertEquals('Миха@domain.com', (string)$address);
+    }
+
     /**
      * @test
      */

test/Unit/Header/BccTest.php

@@ -1,4 +1,4 @@
-<?php 
+<?php
 declare(strict_types=1);
 
 namespace Genkgo\TestMail\Unit\Header;

test/Unit/Header/GenericHeaderTest.php

@@ -1,4 +1,4 @@
-<?php 
+<?php
 declare(strict_types=1);
 
 namespace Genkgo\TestMail\Unit\Header;

test/Unit/Header/ParsedHeaderTest.php

@@ -1,4 +1,4 @@
-<?php 
+<?php
 declare(strict_types=1);
 
 namespace Genkgo\TestMail\Unit\Header;

test/Unit/Header/SubjectTest.php

@@ -24,6 +24,15 @@ public function it_produces_correct_values($subject, $constructed, $headerName,
         }
     }
 
+    /**
+     * @test
+     */
+    public function it_can_be_constructed_with_a_multi_byte_name_leading_to_new_line_in_single_byte()
+    {
+        $subject = new Subject('Миха');
+        $this->assertEquals('=?UTF-8?B?0JzQuNGF0LA=?=', (string)$subject->getValue());
+    }
+
     /**
      * @return array
      */