compatibility with PHPUnit 6

Author: xabbuh

.travis.yml

@@ -28,13 +28,14 @@ matrix:
 before_install:
   - if [[ "$TRAVIS_PHP_VERSION" != "hhvm" && "$xdebug" != "yes" ]]; then phpenv config-rm xdebug.ini; fi
   - composer self-update
+  - composer require 'phpunit/phpunit:^4.8.35|^5.4.3|^6.0' --dev --no-update
 
 install:
   - if [ "$PACKAGES" != "" ]; then composer require --no-update $PACKAGES; fi
   - composer update $COMPOSER_OPTIONS
 
 script:
   - vendor/bin/phpspec run
-  - if [[ "$xdebug" = "yes" ]]; then phpunit --coverage-clover=coverage.clover; else phpunit; fi
+  - if [[ "$xdebug" = "yes" ]]; then vendor/bin/phpunit --coverage-clover=coverage.clover; else vendor/bin/phpunit; fi
   - if [[ "$xdebug" = "yes" ]]; then wget https://scrutinizer-ci.com/ocular.phar; fi
   - if [[ "$xdebug" = "yes" ]]; then php ocular.phar code-coverage:upload --format=php-clover coverage.clover; fi

tests/Api/ApiClientTest.php

@@ -11,6 +11,7 @@
 
 namespace Xabbuh\XApi\Client\Tests\Api;
 
+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Serializer\SerializerInterface;
 use Xabbuh\XApi\Client\Request\HandlerInterface;
 use Xabbuh\XApi\Common\Exception\NotFoundException;
@@ -23,7 +24,7 @@
 /**
  * @author Christian Flothmann <[email protected]>
  */
-abstract class ApiClientTest extends \PHPUnit_Framework_TestCase
+abstract class ApiClientTest extends TestCase
 {
     /**
      * @var HandlerInterface|\PHPUnit_Framework_MockObject_MockObject