Fix tests on Travis CI (#405)

.travis.yml

@@ -19,12 +19,13 @@ env:
 
 matrix:
   exclude:
-    - php: 7.2
-      env: RELEASE=stable COMPOSER_CHANNEL=stable
-    - php: 7.2
+    - php: 5.6
+      env: RELEASE=dev COMPOSER_CHANNEL=stable
+    - php: 5.6
       env: RELEASE=stable COMPOSER_CHANNEL=snapshot
 
 before_install:
+  - if [[ $TRAVIS_PHP_VERSION = 5.6 ]]; then export COMPOSER_MEMORY_LIMIT=-1; fi;
   - echo 'sendmail_path = /bin/true' >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
   - phpenv config-rm xdebug.ini
   - composer --verbose self-update --$COMPOSER_CHANNEL
@@ -44,6 +45,7 @@ script:
   - until curl -s $SIMPLETEST_BASE_URL; do true; done > /dev/null
   # Skip core/tests/Drupal/Tests/ComposerIntegrationTest.php because web/ has no composer.json
   # Ignore PageCache group temporarily, @see https://www.drupal.org/node/2770673
-  - ./../vendor/bin/phpunit -c core --testsuite unit --exclude-group Composer,DependencyInjection,PageCache
+  # Ignore Setup group temporarily, @see https://www.drupal.org/node/2962157
+  - ./../vendor/bin/phpunit -c core --testsuite unit --exclude-group Composer,DependencyInjection,PageCache,Setup
   - ./../vendor/bin/drush
   - if [[ $RELEASE = stable ]]; then ./../vendor/bin/drupal; fi;