From ee39215cc29d8cfde6ef2e7a62d9e8a4740eed75 Mon Sep 17 00:00:00 2001
From: Fabien Potencier <fabien.potencier@gmail.com>
Date: Thu, 5 Jan 2012 15:18:26 +0100
Subject: [PATCH] fixed regression in string parsing (closes #580)

---
 lib/Twig/ExpressionParser.php                     |   12 +++++++-----
 test/Twig/Tests/ExpressionParserTest.php          |   12 ++++++++++++
 test/Twig/Tests/Fixtures/expressions/strings.test |    2 ++
 3 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/lib/Twig/ExpressionParser.php b/lib/Twig/ExpressionParser.php
index e9ed43a..0e6a8df 100644
--- a/lib/Twig/ExpressionParser.php
+++ b/lib/Twig/ExpressionParser.php
@@ -170,23 +170,25 @@ class Twig_ExpressionParser
         $stream = $this->parser->getStream();
 
         $nodes = array();
-
+        // a string cannot be followed by another string in a single expression
+        $nextCanBeString = true;
         while (true) {
-            if ($stream->test(Twig_Token::STRING_TYPE)) {
+            if ($stream->test(Twig_Token::STRING_TYPE) && $nextCanBeString) {
                 $token = $stream->next();
                 $nodes[] = new Twig_Node_Expression_Constant($token->getValue(), $token->getLine());
-            } else if ($stream->test(Twig_Token::INTERPOLATION_START_TYPE)) {
+                $nextCanBeString = false;
+            } elseif ($stream->test(Twig_Token::INTERPOLATION_START_TYPE)) {
                 $stream->next();
                 $nodes[] = $this->parseExpression();
                 $stream->expect(Twig_Token::INTERPOLATION_END_TYPE);
+                $nextCanBeString = true;
             } else {
                 break;
             }
         }
 
         $expr = array_shift($nodes);
-
-        foreach($nodes as $node) {
+        foreach ($nodes as $node) {
             $expr = new Twig_Node_Expression_Binary_Concat($expr, $node, $node->getLine());
         }
 
diff --git a/test/Twig/Tests/ExpressionParserTest.php b/test/Twig/Tests/ExpressionParserTest.php
index bb7b38a..b3f300f 100644
--- a/test/Twig/Tests/ExpressionParserTest.php
+++ b/test/Twig/Tests/ExpressionParserTest.php
@@ -145,6 +145,18 @@ class Twig_Tests_ExpressionParserTest extends PHPUnit_Framework_TestCase
     }
 
     /**
+     * @expectedException Twig_Error_Syntax
+     */
+    public function testStringExpressionDoesNotConcatenateTwoConsecutiveStrings()
+    {
+        $env = new Twig_Environment(new Twig_Loader_String(), array('cache' => false, 'autoescape' => false, 'optimizations' => 0));
+        $stream = $env->tokenize('{{ "a" "b" }}', 'index');
+        $parser = new Twig_Parser($env);
+
+        $parser->parse($stream);
+    }
+
+    /**
      * @dataProvider getTestsForString
      */
     public function testStringExpression($template, $expected)
diff --git a/test/Twig/Tests/Fixtures/expressions/strings.test b/test/Twig/Tests/Fixtures/expressions/strings.test
index a2bff10..a911661 100644
--- a/test/Twig/Tests/Fixtures/expressions/strings.test
+++ b/test/Twig/Tests/Fixtures/expressions/strings.test
@@ -2,7 +2,9 @@
 Twig supports string interpolation
 --TEMPLATE--
 {{ "foo #{"foo #{bar} baz"} baz" }}
+{{ "foo #{bar}#{bar} baz" }}
 --DATA--
 return array('bar' => 'BAR');
 --EXPECT--
 foo foo BAR baz baz
+foo BARBAR baz
-- 
1.7.2.5