diff --git a/.travis.yml b/.travis.yml
index 1914dbdd..828a7959 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -46,7 +46,7 @@ before_script:
  - "export DISPLAY=\":99\""
  - "export XVFBARGS=\":99 -ac -screen 0 1024x768x16\""
  - "export COMPOSER_ROOT_VERSION=4.0.x-dev"
- - "if [ \"$NPM_TEST\" = \"1\" ]; then (nvm install $TRAVIS_NODE_VERSION && npm install --silent); fi"
+ - "if [ \"$NPM_TEST\" = \"1\" ]; then (nvm install $TRAVIS_NODE_VERSION && npm install --silent && npm run build); fi"
  - "if [ \"$BEHAT_TEST\" = \"1\" ]; then sh -e /etc/init.d/xvfb start; sleep 3; fi"
  - "if [ \"$BEHAT_TEST\" = \"1\" ]; then (vendor/bin/selenium-server-standalone > selenium.log 2>&1 &); fi"
  - "if [ \"$BEHAT_TEST\" = \"1\" ]; then (vendor/bin/serve --bootstrap-file tests/behat/serve-bootstrap.php &> serve.log &); fi"
@@ -54,7 +54,9 @@ before_script:
 script:
  - "if [ \"$PHPUNIT_TEST\" = \"1\" ]; then vendor/bin/phpunit tests flush=1; fi"
  - "if [ \"$BEHAT_TEST\" = \"1\" ]; then vendor/bin/behat .; fi"
- - "if [ \"$NPM_TEST\" = \"1\" ]; then (nvm use 4 && npm run lint); fi"
+ - "if [ \"$NPM_TEST\" = \"1\" ]; then git diff-files --quiet -w; fi"
+ - "if [ \"$NPM_TEST\" = \"1\" ]; then git diff -w --no-color; fi"
+ - "if [ \"$NPM_TEST\" = \"1\" ]; then (nvm use $TRAVIS_NODE_VERSION && npm run lint); fi"
  - "if [ \"$PHPUNIT_COVERAGE_TEST\" = \"1\" ]; then phpdbg -qrr vendor/bin/phpunit tests flush=1 --coverage-clover=coverage.xml; fi"
  - "if [ \"$PHPUNIT_COVERAGE_TEST\" = \"1\" ]; then bash <(curl -s https://codecov.io/bash) -f coverage.xml; fi"