Giving --prefer-lowest a try. v2 should test under 5.5, v3 under 5.6

Author: kynx

.travis.yml

@@ -17,15 +17,10 @@ matrix:
     - php: 5.5
       env:
         - EXECUTE_CS_CHECK=true
-    - php: 5.5
-      env:
-        - SERVICE_MANAGER_VERSION="^2.7.5"
+        - SERVICE_MANAGER_V2=true
     - php: 5.6
       env:
         - EXECUTE_TEST_COVERALLS=true
-    - php: 5.6
-      env:
-        - SERVICE_MANAGER_VERSION="^2.7.5"
     - php: 7
     - php: hhvm 
   allow_failures:
@@ -41,14 +36,13 @@ before_install:
   - if [[ $EXECUTE_TEST_COVERALLS == 'true' ]]; then composer require --dev --no-update satooshi/php-coveralls ; fi
 
 install:
-  - travis_retry composer install --no-interaction --ignore-platform-reqs
+  - if [[ $SERVICE_MANAGER_V2 != 'true' ]]; then travis_retry composer install --no-interaction --ignore-platform-reqs ; fi
+  - if [[ $SERVICE_MANAGER_V2 == 'true' ]]; then travis_retry composer update --no-interaction --ignore-platform-reqs --prefer-lowest ; fi
 
 script:
   - if [[ $EXECUTE_TEST_COVERALLS == 'true' ]]; then ./vendor/bin/phpunit --coverage-clover clover.xml ; fi
   - if [[ $EXECUTE_TEST_COVERALLS != 'true' ]]; then ./vendor/bin/phpunit ; fi
   - if [[ $EXECUTE_CS_CHECK == 'true' ]]; then ./vendor/bin/php-cs-fixer fix -v --diff --dry-run ; fi
-  - if [[ $SERVICE_MANAGER_VERSION != '' ]]; then composer require --no-update "zendframework/zend-servicemanager:$SERVICE_MANAGER_VERSION" ; fi
-  - if [[ $SERVICE_MANAGER_VERSION == '' ]]; then composer require --no-update "zendframework/zend-servicemanager:^3.0.3" ; fi
 
 after_script:
   - if [[ $EXECUTE_TEST_COVERALLS == 'true' ]]; then ./vendor/bin/coveralls ; fi