Use PSR-4 for autoloading, works same as the PSR-0 configuration. Use...

Use PSR-4 for autoloading, works same as the PSR-0 configuration. Use autoload-dev for autoloading tests

composer.json

@@ -52,7 +52,10 @@
         "symfony/form": "~2.3"
     },
     "autoload": {
-        "psr-0": { "Silex": "src/" }
+        "psr-4": { "Silex\\": "src/Silex" }
+    },
+    "autoload-dev" : {
+        "psr-4": { "Silex\\Tests\\" : "tests/Silex/Tests" }
     },
     "extra": {
         "branch-alias": {

phpunit.xml.dist

@@ -9,7 +9,7 @@
          processIsolation="false"
          stopOnFailure="false"
          syntaxCheck="false"
-         bootstrap="tests/bootstrap.php"
+         bootstrap="vendor/autoload.php"
 >
     <testsuites>
         <testsuite name="Silex Test Suite">

tests/bootstrap.php

-<?php
-
-$loader = require __DIR__.'/../vendor/autoload.php';
-$loader->add('Silex\Tests', __DIR__);
-
-if (!class_exists('Symfony\Component\Form\Form')) {
-    echo "You must install the dev dependencies using:\n";
-    echo "    composer install --dev\n";
-    exit(1);
-}