title: Namespaces used for test in official exemple don't work for me
body: <p>I have been trying to dowload the GraphQL version of PHP at this link: <a href="https://github.com/webonyx/graphql-php" rel="nofollow noreferrer">https://github.com/webonyx/graphql-php</a> (I git cloned then used "composer require webonyx/graphql-php")</p>
  
  <p>But when I tried to execute the code included in the "test" folder, I kept getting mistakes for class "..." not found</p>
  
  <p>I first tried launching this example (GraphQLTest):</p>
  
  <pre><code>&lt;?php
  
  declare(strict_types=1);
  
  namespace GraphQL\Tests;
  
  use GraphQL\Executor\Promise\Adapter\SyncPromiseAdapter;
  use GraphQL\GraphQL;
  use GraphQL\Type\Definition\ObjectType;
  use GraphQL\Type\Definition\Type;
  use GraphQL\Type\Schema;
  use PHPUnit\Framework\TestCase;
  use function sprintf;
  
  class GraphQLTest extends TestCase
  {
      public function testPromiseToExecute() : void
      {
          $promiseAdapter = new SyncPromiseAdapter();
          $schema         = new Schema(
              [
                  'query' =&gt; new ObjectType(
                      [
                          'name' =&gt; 'Query',
                          'fields' =&gt; [
                              'sayHi' =&gt; [
                                  'type' =&gt; Type::nonNull(Type::string()),
                                  'args' =&gt; [
                                      'name' =&gt; [
                                          'type' =&gt; Type::nonNull(Type::string()),
                                      ],
                                  ],
                                  'resolve' =&gt; static function ($value, $args) use ($promiseAdapter) {
                                      return $promiseAdapter-&gt;createFulfilled(sprintf('Hi %s!', $args['name']));
                                  },
                              ],
                          ],
                      ]
                  ),
              ]
          );
  
          $promise = GraphQL::promiseToExecute($promiseAdapter, $schema, '{ sayHi(name: "John") }');
          $result  = $promiseAdapter-&gt;wait($promise);
          self::assertSame(['data' =&gt; ['sayHi' =&gt; 'Hi John!']], $result-&gt;toArray());
      }
  }
  $t = new GraphQLTest();
  $t-&gt;testPromiseToExecute();
  </code></pre>
  
  <p>It's just the test, but I added a line at the end to launch the function</p>
  
  <p>But I got error : </p>
  
  <pre><code>Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in C:\Users\antoine\Desktop\boulot\Graphql\php\graphql-php\tests\GraphQLTest.php:15
  </code></pre>
  
  <p>The program doesn't know PHPunit, so i reinstall it in the parent folder, the current folder, nothing works.</p>
  
  <p>As a last resort, I modified the test to transform it into this code that doesn't use phpunit:</p>
  
  <pre><code>&lt;?php
  
  declare(strict_types=1);
  
  namespace GraphQL\Tests;
  
  use GraphQL\Executor\Promise\Adapter\SyncPromiseAdapter;
  use GraphQL\GraphQL;
  use GraphQL\Type\Definition\ObjectType;
  use GraphQL\Type\Definition\Type;
  use GraphQL\Type\Schema;
  use function sprintf;
  
  class GraphQLTest
  {
      public function testPromiseToExecute() : void
      {
          $promiseAdapter = new SyncPromiseAdapter();
          $schema         = new Schema(
              [
                  'query' =&gt; new ObjectType(
                      [
                          'name' =&gt; 'Query',
                          'fields' =&gt; [
                              'sayHi' =&gt; [
                                  'type' =&gt; Type::nonNull(Type::string()),
                                  'args' =&gt; [
                                      'name' =&gt; [
                                          'type' =&gt; Type::nonNull(Type::string()),
                                      ],
                                  ],
                                  'resolve' =&gt; static function ($value, $args) use ($promiseAdapter) {
                                      return $promiseAdapter-&gt;createFulfilled(sprintf('Hi %s!', $args['name']));
                                  },
                              ],
                          ],
                      ]
                  ),
              ]
          );
  
          $promise = GraphQL::promiseToExecute($promiseAdapter, $schema, '{ sayHi(name: "John") }');
          $result  = $promiseAdapter-&gt;wait($promise);
          echo $result-&gt;toArray();
      }
  }
  $t= new GraphQLTest();
  $t-&gt;testPromiseToExecute();
  </code></pre>
  
  <p>But I still get an error : </p>
  
  <pre><code>Fatal error: Uncaught Error: Class 'GraphQL\Executor\Promise\Adapter\SyncPromiseAdapter' not found in C:\Users\antoine\Desktop\boulot\Graphql\php\graphql-php\tests\GraphQLTest.php:18
  </code></pre>
  
  <p>This is a tested release, the namespaces should not cause problems. I didn't change anything in these folders, how on earth are they not recognized? I had similar problems yesterday too when trying (unsuccessfully) to install GraphQLite. </p>
  
  <p>I'm guessing my setup isn't good, thus making namespaces behave strangely, but I have no idea how to check that.</p>
  
  <p>Does anyone have any idea?</p>