Improve Travis configuration, add PHP-CS-Fixer and update PHPUnit minimum version

Author: tgalopin

.gitignore

@@ -1,4 +1,5 @@
 vendor/
 scratch.php
 composer.lock
-build/
+build/
+.php_cs.cache

.travis.yml

@@ -1,40 +1,41 @@
 language: php
-
+dist: trusty
 sudo: false
 
-php:
-  - 5.4
-  - 5.5
-  - 5.6
-  - 7.0
-  - 7.1
-  - 7.2
-  - hhvm
-
 matrix:
-    include:
-        - php: 5.3
-          dist: precise
-    fast_finish: true
-
-dist: trusty
+  include:
+    - php: 5.3
+      dist: precise
+    - php: 5.4
+    - php: 5.5
+    - php: 5.6
+      env: SCRUTINIZER=1
+    - php: 7.0
+      env: COMPOSER_FLAGS="--prefer-lowest"
+    - php: 7.1
+      env: CS_FIXER=1
+    - php: 7.2
+      env: BENCHMARK=1
+    - php: hhvm
+  fast_finish: true
 
 cache:
   directories:
     - $HOME/.composer/cache
 
-notifications:
-  irc: "irc.freenode.net#masterminds"
-
 before_script:
   - composer self-update
-  - composer install
+  - composer update $COMPOSER_FLAGS --prefer-dist
 
 script:
+  - stty cols 120
+  - if [ "$CS_FIXER" == 1 ]; then wget https://github.com/FriendsOfPHP/PHP-CS-Fixer/releases/download/v2.13.1/php-cs-fixer.phar && php php-cs-fixer.phar fix . --dry-run --diff --rules="@Symfony"; fi
   - mkdir -p build/logs
   - ./vendor/bin/phpunit --coverage-clover=coverage.xml
 
 after_script:
-  - bash -c 'if [ "$TRAVIS_PHP_VERSION" == "5.6" ] ; then wget https://scrutinizer-ci.com/ocular.phar; fi;'
-  - bash -c 'if [ "$TRAVIS_PHP_VERSION" == "5.6" ] ; then php ocular.phar code-coverage:upload --format=php-clover coverage.xml; fi;'
-  - php test/benchmark/run.php 10
+  - if [ "$SCRUTINIZER" == 1 ]; then wget https://scrutinizer-ci.com/ocular.phar && php ocular.phar code-coverage:upload --format=php-clover coverage.xml; fi
+  - if [ "$BENCHMARK" == 1 ]; then php test/benchmark/run.php 10; fi
+
+notifications:
+  irc: "irc.freenode.net#masterminds"

composer.json

@@ -27,7 +27,7 @@
     },
     "require-dev": {
         "satooshi/php-coveralls": "1.0.*",
-        "phpunit/phpunit" : "4.*",
+        "phpunit/phpunit" : "^4.8.35",
         "sami/sami": "~2.0"
     },
     "autoload": {