add a limit and a test to FlattenExceptionTest.

src/Symfony/Component/Debug/Exception/FlattenException.php

@@ -239,17 +239,20 @@ class FlattenException
         }
     }
 
-    private function flattenArgs($args, $level = 0)
+    private function flattenArgs($args, $level = 0, &$count = 0)
     {
         $result = array();
         foreach ($args as $key => $value) {
+            if (++$count > 1e4) {
+                return array('array', '*SKIPPED over 10000 entries*');
+            }
             if (is_object($value)) {
                 $result[$key] = array('object', get_class($value));
             } elseif (is_array($value)) {
                 if ($level > 10) {
                     $result[$key] = array('array', '*DEEP NESTED ARRAY*');
                 } else {
-                    $result[$key] = array('array', $this->flattenArgs($value, $level + 1));
+                    $result[$key] = array('array', $this->flattenArgs($value, $level + 1, $count));
                 }
             } elseif (null === $value) {
                 $result[$key] = array('null', null);

src/Symfony/Component/Debug/Tests/Exception/FlattenExceptionTest.php

@@ -186,6 +186,28 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
         $this->assertContains('*DEEP NESTED ARRAY*', serialize($trace));
     }
 
+    public function testTooBigArray()
+    {
+        $a = array();
+        for ($i = 0; $i < 20; $i++) {
+            for ($j = 0; $j < 50; $j++) {
+                for ($k = 0; $k < 10; $k++) {
+                    $a[$i][$j][$k] = 'value';
+                }
+            }
+        }
+        $a[20] = 'value';
+        $a[21] = 'value1';
+        $exception = $this->createException($a);
+
+        $flattened = FlattenException::create($exception);
+        $trace = $flattened->getTrace();
+        $serialize_trace = serialize($trace);
+
+        $this->assertContains('*SKIPPED over 10000 entries*', $serialize_trace);
+        $this->assertNotContains('*value1*', $serialize_trace);
+    }
+
     private function createException($foo)
     {
         return new \Exception();