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bug: importScripts is not defined error inside web worker script

See original GitHub issue

I have a web worker worker.js that references a file e.g:

importScripts('file.js');

However Karma does not seem to like it:

INFO [karma]: Karma v0.12.37 server started at http://localhost:9877/
INFO [launcher]: Starting browser Chrome
INFO [Chrome 44.0.2403 (Linux 0.0.0)]: Connected on socket ZecIQTwPUPehOMzVhz-8 with id 85867718
Chrome 44.0.2403 (Linux 0.0.0) LOG: 'pre-main prep time: 2 ms'

Chrome 44.0.2403 (Linux 0.0.0) ERROR
    Uncaught ReferenceError: importScripts is not defined at /home/.../worker.js:1

importScripts is a standard API of the Worker global scope so it should not throw this error

Issue Analytics

State:
Created 8 years ago
Comments:10 (5 by maintainers)

Top GitHub Comments

4reactions

dignifiedquirecommented, Jul 27, 2015

This sounds like the script is not executed in a web worker, but rather in the general browser scope. Try opening the debug mode and look at what actually happens on execution. (This error is not coming from karma, it’s just relaying the error that Chrome sends)

0reactions

johnjbartoncommented, May 14, 2020

I don’t see anything in the stackoverflow post related to karma issues.

The karma test is just a web page and if your test configuration includes bad code then the page will fail with errors. The TroubleShooting page gives the recommended approach. http://karma-runner.github.io/5.0/intro/troubleshooting.html Basically you start your tests but the server does not exit. Then you use the browser debugger to find issues.