diff --git a/tests/AppTest.php b/tests/AppTest.php
index 61d7091..bc875e6 100644
--- a/tests/AppTest.php
+++ b/tests/AppTest.php
@@ -16,6 +16,33 @@ use Throwable;
 final class AppTest extends TestCase {
 
     /**
+     * register error handlers
+     */
+    public function testInit()
+    {
+        $displayErrors = true;
+        set_error_handler(function(
+            int $errno,
+            string $errstr,
+            ?string $errfile = null,
+            ?int $errline = null,
+            ?array $errcontext = null
+        ) use (&$displayErrors){
+            if ($displayErrors){
+                echo "\nError $errstr ($errno)\nIn file $errfile\nLine : $errline\n";
+            }
+        });
+        register_shutdown_function(function (){
+            $lastErr = error_get_last();
+            if (!is_null($lastErr)){
+                echo "\nAn error occured\n".json_encode($lastErr)."\n";
+            }
+        });
+        $this->assertTrue($displayErrors);
+    }
+
+    /**
+     * @depends testInit
      * @dataProvider apiRewriteProvider
      * @covers App::update_SERVERIfNeeded 
      * @param string $rootFolder,
@@ -62,7 +89,7 @@ final class AppTest extends TestCase {
         return $data;
     }
 
-    public function prepareData(
+    protected function prepareData(
         array &$data, 
         string $name, 
         string $rootFolder,