bug #1258 Fix twig_first and twig_last filters for UTF8 multibyte strings (chEbba)

This PR was squashed before being merged into the master branch (closes #1258).

Discussion
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Fix twig_first and twig_last filters for UTF8 multibyte strings

After string is sliced we already have the right result with a first/last letter for UTF8 string.

Commits
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6003ae4 Fix twig_first and twig_last filters for UTF8 multibyte strings

lib/Twig/Extension/Core.php

@@ -693,7 +693,7 @@ function twig_first(Twig_Environment $env, $item)
 {
     $elements = twig_slice($env, $item, 0, 1, false);
 
-    return is_string($elements) ? $elements[0] : current($elements);
+    return is_string($elements) ? $elements : current($elements);
 }
 
 /**
@@ -708,7 +708,7 @@ function twig_last(Twig_Environment $env, $item)
 {
     $elements = twig_slice($env, $item, -1, 1, false);
 
-    return is_string($elements) ? $elements[0] : current($elements);
+    return is_string($elements) ? $elements : current($elements);
 }
 
 /**

test/Twig/Tests/Fixtures/filters/first.test

@@ -5,6 +5,7 @@
 {{ {a: 1, b: 2, c: 3, d: 4}|first }}
 {{ '1234'|first }}
 {{ arr|first }}
+{{ 'Ä€é'|first }}
 --DATA--
 return array('arr' => new ArrayObject(array(1, 2, 3, 4)))
 --EXPECT--
@@ -12,3 +13,4 @@ return array('arr' => new ArrayObject(array(1, 2, 3, 4)))
 1
 1
 1
+Ä

test/Twig/Tests/Fixtures/filters/last.test

@@ -5,6 +5,7 @@
 {{ {a: 1, b: 2, c: 3, d: 4}|last }}
 {{ '1234'|last }}
 {{ arr|last }}
+{{ 'Ä€é'|last }}
 --DATA--
 return array('arr' => new ArrayObject(array(1, 2, 3, 4)))
 --EXPECT--
@@ -12,3 +13,4 @@ return array('arr' => new ArrayObject(array(1, 2, 3, 4)))
 4
 4
 4
+é