validation: Fixup a few email address validations

include/class.validator.php

@@ -140,13 +140,23 @@ class Validator {
 
     /*** Functions below can be called directly without class instance.
          Validator::func(var..);  (nolint) ***/
-    function is_email($email) {
-        if (strpos($email, '@') === false)
-            return false;
-
+    function is_email($email, $list=false) {
         require_once 'Mail/RFC822.php';
         require_once 'PEAR.php';
-        return !PEAR::isError(Mail_RFC822::parseAddressList($email));
+        if (!($mails = Mail_RFC822::parseAddressList($email)) || PEAR::isError($mails))
+            return false;
+
+        if (!$list && count($mails) > 1)
+            return false;
+
+        foreach ($mails as $m) {
+            if (!$m->mailbox)
+                return false;
+            if ($m->host == 'localhost')
+                return false;
+        }
+
+        return true;
     }
     function is_phone($phone) {
         /* We're not really validating the phone number but just making sure it doesn't contain illegal chars and of acceptable len */

setup/test/tests/test.validation.php

@@ -37,6 +37,9 @@ class TestValidation extends Test {
         // Illegal or unsupported
         $this->assert(!Validator::is_email('jared r@domain.tld'));
         $this->assert(!Validator::is_email('jared'));
+        $this->assert(!Validator::is_email('jared@'));
+        $this->assert(!Validator::is_email('@domain.tld'));
+        $this->assert(!Validator::is_email('@domain.tld, @domain2.tld'));
 
         // Odd cases, but legal
         $this->assert(Validator::is_email('jared@host'));