Merge pull request #588 from xabbuh/patch-1

install stable dependencies when possible

.travis.yml

@@ -24,12 +24,12 @@ matrix:
     - php: 7.1
       env: SYMFONY_VERSION='~4.0@dev'
     - php: 5.5
-      env: 'COMPOSER_FLAGS="--prefer-stable --prefer-lowest"'
+      env: 'COMPOSER_FLAGS="--prefer-lowest"'
 
 before_script:
   - if [[ "$TRAVIS_PHP_VERSION" != "hhvm" ]]; then echo "memory_limit = -1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini; fi
   - if [ "$SYMFONY_VERSION" != "" ]; then composer require --dev --no-update symfony/symfony=$SYMFONY_VERSION; fi
-  - composer update ${COMPOSER_FLAGS} --no-interaction
+  - composer update ${COMPOSER_FLAGS} --prefer-stable --no-interaction
 
 script:
   - vendor/bin/phpunit --coverage-clover clover