add xdebug.mode = coverage as suggested by the error message #10

Author: gregor-j

.travis.yml

@@ -15,6 +15,7 @@ before_script:
   - chmod +x ./cc-test-reporter
   - ./cc-test-reporter before-build
   - composer install --no-interaction --ignore-platform-reqs
+  - echo 'xdebug.mode = "coverage"' >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
 script:
   - vendor/bin/phpunit --coverage-clover clover.xml
 after_script: