Fix local part length check (#233)

Added a check that `$previous` is not null (i.e. previous token exists)

EmailValidator/Parser/LocalPart.php

@@ -19,6 +19,7 @@ class LocalPart extends Parser
         $parseDQuote = true;
         $closingQuote = false;
         $openedParenthesis = 0;
+        $totalLength = 0;
 
         while ($this->lexer->token['type'] !== EmailLexer::S_AT && null !== $this->lexer->token['type']) {
             if ($this->lexer->token['type'] === EmailLexer::S_DOT && null === $this->lexer->getPrevious()['type']) {
@@ -34,12 +35,13 @@ class LocalPart extends Parser
                 $this->parseComments();
                 $openedParenthesis += $this->getOpenedParenthesis();
             }
+
             if ($this->lexer->token['type'] === EmailLexer::S_CLOSEPARENTHESIS) {
                 if ($openedParenthesis === 0) {
                     throw new UnopenedComment();
-                } else {
-                    $openedParenthesis--;
                 }
+
+                $openedParenthesis--;
             }
 
             $this->checkConsecutiveDots();
@@ -57,11 +59,11 @@ class LocalPart extends Parser
                 $this->parseFWS();
             }
 
+            $totalLength += strlen($this->lexer->token['value']);
             $this->lexer->moveNext();
         }
 
-        $prev = $this->lexer->getPrevious();
-        if (strlen($prev['value']) > LocalTooLong::LOCAL_PART_LENGTH) {
+        if ($totalLength > LocalTooLong::LOCAL_PART_LENGTH) {
             $this->warnings[LocalTooLong::CODE] = new LocalTooLong();
         }
     }

EmailValidator/Parser/Parser.php

@@ -170,7 +170,7 @@ abstract class Parser
     {
         $previous = $this->lexer->getPrevious();
 
-        if ($previous['type'] === EmailLexer::S_BACKSLASH
+        if ($previous && $previous['type'] === EmailLexer::S_BACKSLASH
             &&
             $this->lexer->token['type'] !== EmailLexer::GENERIC
         ) {

Tests/EmailValidator/Validation/RFCValidationTest.php

@@ -265,6 +265,10 @@ class RFCValidationTest extends TestCase
                 [LocalTooLong::CODE,],
                 'too_long_localpart_too_long_localpart_too_long_localpart_too_long_localpart@invalid.example.com'
             ],
+            [
+                [LocalTooLong::CODE],
+                'too_long_localpart_too_long_localpart_123_too_long_localpart_too_long_localpart@example.com'
+            ],
             [
                 [LabelTooLong::CODE,],
                 'example@toolonglocalparttoolonglocalparttoolonglocalparttoolonglocalpart.co.uk'