Require sudo and prefer-lowest

Author: Nyholm

.travis.yml

@@ -5,31 +5,36 @@ php:
   - "5.6"
   - "5.5"
 
+sudo: required
+
 services:
   - memcached
   - redis-server
 
 env:
-  - SYMFONY_VERSION=2.6.*
-  - SYMFONY_VERSION=2.7.*
-  - SYMFONY_VERSION=2.8.*
-  - SYMFONY_VERSION=3.0.*
+  global:
+    - COMPOSER_COMMAND="composer install --prefer-dist"
+  matrix:
+    - SYMFONY_VERSION=2.6.*
+    - SYMFONY_VERSION=2.7.*
+    - SYMFONY_VERSION=2.8.*
+    - SYMFONY_VERSION=3.0.*
 
 matrix:
   fast_finish: true
-
-sudo: false
+  include:
+    - php: 5.5
+      env: COMPOSER_COMMAND="composer update --prefer-lowest --prefer-stable" && SYMFONY_VERSION=2.7.*
 
 before_script:
   - mkdir -p ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d
   - echo "memory_limit=-1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
-  - echo "extension=mongo.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
   - echo "extension=memcached.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
   - echo "extension=redis.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
   - if [[ $TRAVIS_PHP_VERSION != 'hhvm' && `php-config --vernum` -ge 70000 ]]; then pecl config-set preferred_state beta; printf "yes\n" | pecl install apcu; else echo "extension=apc.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini; fi;
   - composer self-update
   - composer require symfony/symfony:${SYMFONY_VERSION} --no-update
-  - composer install --dev --prefer-dist --no-interaction
+  - travis_retry ${COMPOSER_COMMAND} --no-interaction
   # must be set after composer to avoid issue with autoloading
   - echo "apc.enable_cli=On" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini