Relax email validation rules even more.

While filter_var() allows a number of email addresses that
Validation::email() does not, it misses out of email address that
contain IDN host names, and unicode mailboxes. Both of these are
generally deliverable, and should be permitted. filter_var() also fails
on local mailboxes like `root@localhost` which is useful in the context
of cron jobs.

Fixes #3742

lib/Cake/Network/Email/CakeEmail.php

@@ -314,11 +314,13 @@ class CakeEmail {
 
 /**
  * Regex for email validation
- * If null, filter_var() will be used.
+ *
+ * If null, filter_var() will be used. Use the emailPattern() method
+ * to set a custom pattern.'
  *
  * @var string
  */
-	protected $_emailPattern = null;
+	protected $_emailPattern = '/^((?:[\p{L}0-9!#$%&\'*+\/=?^_`{|}~-]+)*@[\p{L}0-9-.]+)$/ui';
 
 /**
  * The class name used for email configuration.
@@ -547,8 +549,8 @@ public function headerCharset($charset = null) {
  * @param string $regex for email address validation
  * @return string|$this
  */
-	public function emailPattern($regex = null) {
-		if ($regex === null) {
+	public function emailPattern($regex = false) {
+		if ($regex === false) {
 			return $this->_emailPattern;
 		}
 		$this->_emailPattern = $regex;
@@ -593,13 +595,12 @@ protected function _setEmail($varName, $email, $name) {
  * @throws SocketException If email address does not validate
  */
 	protected function _validateEmail($email) {
-		$valid = (($this->_emailPattern !== null &&
-			preg_match($this->_emailPattern, $email)) ||
-			filter_var($email, FILTER_VALIDATE_EMAIL)
-		);
-		if (!$valid) {
-			throw new SocketException(__d('cake_dev', 'Invalid email: "%s"', $email));
+		if ($this->_emailPattern === null && filter_var($email, FILTER_VALIDATE_EMAIL)) {
+			return;
+		} elseif (preg_match($this->_emailPattern, $email)) {
+			return;
 		}
+		throw new SocketException(__d('cake_dev', 'Invalid email: "%s"', $email));
 	}
 
 /**

lib/Cake/Test/Case/Network/Email/CakeEmailTest.php

@@ -249,12 +249,16 @@ public function testTo() {
 		$this->assertSame($this->CakeEmail->to(), $expected);
 
 		$list = array(
+			'root@localhost' => 'root',
+			'bjørn@hammeröath.com' => 'Bjorn',
 			'cake@cakephp.org' => 'Cake PHP',
 			'cake-php@googlegroups.com' => 'Cake Groups',
 			'root@cakephp.org'
 		);
 		$this->CakeEmail->to($list);
 		$expected = array(
+			'root@localhost' => 'root',
+			'bjørn@hammeröath.com' => 'Bjorn',
 			'cake@cakephp.org' => 'Cake PHP',
 			'cake-php@googlegroups.com' => 'Cake Groups',
 			'root@cakephp.org' => 'root@cakephp.org'
@@ -265,6 +269,8 @@ public function testTo() {
 		$this->CakeEmail->addTo('mark_story@cakephp.org', 'Mark Story');
 		$result = $this->CakeEmail->addTo(array('phpnut@cakephp.org' => 'PhpNut', 'jose_zap@cakephp.org'));
 		$expected = array(
+			'root@localhost' => 'root',
+			'bjørn@hammeröath.com' => 'Bjorn',
 			'cake@cakephp.org' => 'Cake PHP',
 			'cake-php@googlegroups.com' => 'Cake Groups',
 			'root@cakephp.org' => 'root@cakephp.org',
@@ -275,11 +281,9 @@ public function testTo() {
 		);
 		$this->assertSame($this->CakeEmail->to(), $expected);
 		$this->assertSame($this->CakeEmail, $result);
-
-		$this->setExpectedException('SocketException');
-		$this->CakeEmail->to(array('cake@localhost', 'CakePHP'));
 	}
 
+
 /**
  * Data provider function for testBuildInvalidData
  *
@@ -291,8 +295,6 @@ public static function invalidEmails() {
 			array(''),
 			array('string'),
 			array('<tag>'),
-			array('some@one-whereis'),
-			array('wrong@key' => 'Name'),
 			array(array('ok@cakephp.org', 1.0, '', 'string'))
 		);
 	}