minor #6 PHPUnit 6 compatibility (Lctrs)

This PR was squashed before being merged into the 0.4.x-dev branch (closes #6).

Discussion
----------

PHPUnit 6 compatibility

Commits
-------

14dd54b PHPUnit 6 compatibility

Author: xabbuh

.travis.yml

@@ -24,11 +24,15 @@ matrix:
     - php: 5.3
       env: deps="low"
 
+before_install:
+  - composer self-update
+  - composer require 'phpunit/phpunit:^4.8.35|^5.4.3|^6.0' --dev --no-update
+
 install:
   - if [ "$deps" = "low" ]; then composer update --prefer-lowest --prefer-stable; fi
   - if [ "$deps" = "" ]; then composer install; fi
 
 script:
-  - phpunit --coverage-clover=coverage.clover
+  - vendor/bin/phpunit --coverage-clover=coverage.clover
   - wget https://scrutinizer-ci.com/ocular.phar
   - php ocular.phar code-coverage:upload --format=php-clover coverage.clover

src/Test/Unit/Repository/Mapping/StatementRepositoryTest.php

@@ -11,14 +11,15 @@
 
 namespace XApi\Repository\Doctrine\Test\Unit\Repository\Mapping;
 
+use PHPUnit\Framework\TestCase;
 use Xabbuh\XApi\DataFixtures\StatementFixtures;
 use XApi\Repository\Doctrine\Mapping\Statement;
 use XApi\Repository\Doctrine\Repository\Mapping\StatementRepository;
 
 /**
  * @author Christian Flothmann <[email protected]>
  */
-abstract class StatementRepositoryTest extends \PHPUnit_Framework_TestCase
+abstract class StatementRepositoryTest extends TestCase
 {
     /**
      * @var \PHPUnit_Framework_MockObject_MockObject

tests/Unit/Repository/StatementRepositoryTest.php

@@ -11,6 +11,7 @@
 
 namespace XApi\Repository\Doctrine\Tests\Unit\Repository;
 
+use PHPUnit\Framework\TestCase;
 use Rhumsaa\Uuid\Uuid as RhumsaUuid;
 use Xabbuh\XApi\DataFixtures\StatementFixtures;
 use Xabbuh\XApi\DataFixtures\VerbFixtures;
@@ -23,7 +24,7 @@
 /**
  * @author Christian Flothmann <[email protected]>
  */
-class StatementRepositoryTest extends \PHPUnit_Framework_TestCase
+class StatementRepositoryTest extends TestCase
 {
     /**
      * @var \PHPUnit_Framework_MockObject_MockObject|\XApi\Repository\Doctrine\Repository\Mapping\StatementRepository
@@ -122,6 +123,8 @@ public function testSaveWithoutFlush()
      */
     protected function createMappedStatementRepositoryMock()
     {
-        return $this->getMock('\XApi\Repository\Doctrine\Repository\Mapping\StatementRepository');
+        return $this
+            ->getMockBuilder('\XApi\Repository\Doctrine\Repository\Mapping\StatementRepository')
+            ->getMock();
     }
 }