Ask Travis to wait longer for PHPUnit to finish

.travis.yml

@@ -30,7 +30,7 @@ script:
   ## PHP-CS-Fixer
   - ./vendor/bin/php-cs-fixer fix --diff --verbose
   ## PHPUnit
-  - ./vendor/bin/phpunit --coverage-clover coverage-clover.xml
+  - travis_wait 30 ./vendor/bin/phpunit --coverage-clover coverage-clover.xml
 
 after_script:
   - if [ "$TRAVIS_PHP_VERSION" = "7.0" ]; then wget https://scrutinizer-ci.com/ocular.phar && php ocular.phar code-coverage:upload --format=php-clover tests/coverage-clover.xml ; fi

tests/PhpSpreadsheetTests/SampleTest.php

@@ -11,6 +11,10 @@ class SampleTest extends \PHPUnit_Framework_TestCase
      */
     public function testSample($sample)
     {
+        // Suppress output to console
+        $this->setOutputCallback(function () {
+        });
+
         require $sample;
     }