Javascript - I see no coverage in Front End Tests

Owned by Marc Amouyal
Last updated: Dec 14, 2020
2 min read

Problem

I have instrumented my code and used it however I see no coverage reported for my files.

Solutions

Disable caching in your Browser

In Chrome, open the Developer mode (F12), and check the 'Disable cache option under the Network tab.

Developer mode in Google Chrome

Validate the Instrumentation and build number in the JS source from the Browser

In your Browser, open the source code of your JS page: is there the Sealights' instrumentation code and the right build number?

Validate the application is using instrumented source and not compressed files from the Build stage 

  • Check JS is not compressed at the Application Server and therefore confirm the instrumented files are the one used

Validate the application is using the static instrumented files and not files in memory

  • Check your configuration is not using a In-Memory server (e.g. Webpack's server) and serves to your browser client the static files instrumented

  • You can try a simple http server like httpster for a quick validation via a command similar to httpster -p 8080 -d /home/somedir/public_html