Nice setup for testing using Circle CI

circle.yml

machine:
  php:
    version: 7.1.3

dependencies:
  pre:
    - mkdir -p ~/.composer/cache
    - mkdir -p ~/.php-cs-fixer
    - echo "memory_limit = 256M" > /opt/circleci/php/$(phpenv global)/etc/conf.d/memory.ini
  override:
    - composer install --prefer-dist --optimize-autoloader --no-interaction --no-scripts
    - vendor/bin/php-cs-fixer fix --config=.php_cs.dist --cache-file ~/.php-cs-fixer/.php_cs.cache --diff --verbose
  cache_directories:
    - ~/.composer/cache
    - ~/.php-cs-fixer

test:
  override:
    - mkdir -p $CIRCLE_TEST_REPORTS/phpunit
    - vendor/bin/phpunit --log-junit $CIRCLE_TEST_REPORTS/phpunit/junit.xml
    - mkdir -p $CIRCLE_TEST_REPORTS/behat
    - vendor/bin/behat --out $CIRCLE_TEST_REPORTS/behat/test.log
  post:
    - FILES_WITHOUT_LF_AT_EOF=$(for file in $(git grep --cached -Il ''); do test $(tail -c 1 $file) && echo $file; done); if [[ -n $FILES_WITHOUT_LF_AT_EOF ]]; then echo -e "Some files have missing LF at EOF:\n$FILES_WITHOUT_LF_AT_EOF" && exit 1; fi;
    - FILES_WITH_TRAILING_WHITESPACES=$(git grep --cached -Il " $"); if [[ $FILES_WITH_TRAILING_WHITESPACES ]]; then echo -e "Some files have trailing whitespaces at line endings:\n$FILES_WITH_TRAILING_WHITESPACES" && exit 1; fi;
    - vendor/bin/phpmd src/ text phpmd.xml.dist --ignore-violations-on-exit

phpmd.xml.dist

<?xml version="1.0"?>
<ruleset name="My project PHPMD rule set"
         xmlns="http://pmd.sf.net/ruleset/1.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://pmd.sf.net/ruleset/1.0.0
                     http://pmd.sf.net/ruleset_xml_schema.xsd"
         xsi:noNamespaceSchemaLocation="
                     http://pmd.sf.net/ruleset_xml_schema.xsd">
    <description>
        My project rule set
    </description>
    <!-- Import the entire cyclomatic complexity rule -->
    <rule ref="rulesets/controversial.xml/Superglobals" />
    <rule ref="rulesets/design.xml/ExitExpression" />
    <rule ref="rulesets/design.xml/EvalExpression" />
    <rule ref="rulesets/design.xml/GotoStatement" />
    <rule ref="rulesets/naming.xml/ConstantNamingConventions" />
    <rule ref="rulesets/unusedcode.xml" />
</ruleset>

phpunit.xml.dist

<?xml version="1.0" encoding="UTF-8"?>

<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.8/phpunit.xsd"
         backupGlobals="false"
         backupStaticAttributes="false"
         colors="true"
         convertErrorsToExceptions="true"
         convertNoticesToExceptions="true"
         convertWarningsToExceptions="true"
         processIsolation="false"
         stopOnFailure="false"
         syntaxCheck="false"
         bootstrap="vendor/autoload.php"
>
    <php>
        <ini name="error_reporting" value="-1" />
    </php>

    <testsuites>
        <testsuite name="My project test suite">
            <directory>./tests</directory>
        </testsuite>
    </testsuites>

    <filter>
        <whitelist>
            <directory>src</directory>
        </whitelist>
    </filter>
</phpunit>