add test to make sure browser build works as commonJS module

Author: joshgoebel

.travis.yml

@@ -29,5 +29,7 @@ script:
       npm run test
     else
       npm run test-browser
+      # our browser build should also work fine as a Node.js CommonJS module
+      node test/builds/browser_build_as_commonjs.js
     fi
 sudo: false  # Use container-based architecture

test/builds/browser_build_as_commonjs.js

@@ -0,0 +1,6 @@
+const hljs = require("../../build/highlight");
+
+let major = parseInt(majorVersion=hljs.versionString.split("."))
+if (major != 10) {
+  process.exit(1)
+}