Allow specifying the javascript version in the debug html window

[simonzack]

I would like to test javascript 1.8 as this is what I would like my target to run on (greasemonkey on firefox), but currently SCRIPT_TYPE is hard-coded

        return util.format(SCRIPT_TAG, SCRIPT_TYPE[fileExt] || 'text/javascript', filePath)

without application/javascript;version=1.8 firefox runs ES5 only, so can there be some option to put this in the config?

[Moumi]

@simonzack This is possible to do. However, in case the user uses multiple browsers, this might go wrong. If, in any case Chrome is used to run besides Firefox 4 (which supports 1.8 now), the tag will make the tests all fail. Even more, Karma will throw an Error.

I was able to make the configuration for you and was wanting to add a PR for it, but I stumbled upon the error part of Karma when trying to add the tag when running Chrome. Maybe @dignifiedquire has an idea how to make this fail-safe?

[dignifiedquire]

Not sure (I never had to use this in a real world example before)
But we just merged custom context and debug files in #1825 so maybe that can help you to specify exactly what you want.

[Moumi]

I have seen that, but it is not exactly what I'm looking for. The case would be that Firefox 4 supports 1.8, but Chrome (even latest version) does not. This makes it that in the karma.js-file, when the Firefox 4 browser is run, it should add the tag of ";version=1.8", otherwise not. I'd think that there should be some check which browser is being run at that moment and perhaps the version of it.

This might be a solution to it, but takes the effort to update this whitelist of browsers to be updated everytime a new update comes out...

EDIT: It also seems that Firefox is the only browser that supports the ";version=..." tag. So, would there be a way to check which browser actually is being run at the moment?

[Moumi]

@dignifiedquire: Do you know a possible way to capture the current browser being run? That would solve the issue mainly.

[dignifiedquire]

@Moumi capture it where?

[Moumi]

@dignifiedquire: At https://github.com/karma-runner/karma/blob/master/lib/middleware/karma.js just before the return statement:
return util.format(SCRIPT_TAG, SCRIPT_TYPE[fileExt] || 'text/javascript', filePath)

[Moumi]

@dignifiedquire ping

[dignifiedquire]

I don't think that will easily work as the file is simply served to every browser the same atm. You could check the express docs how to do browser detection in a single request

[Moumi]

@dignifiedquire I managed to get the full functionality working. I wanted to create a PR, but I wanted to write a test or 2 for it too. However, it seems very difficult to test it. The check to add the tag depends on:

1. If the configuration is set
2. If the current browser is Firefox. Which is derived from a request and the user-agent header in it.

Well, how can you force during a test that the user-agent should say "Firefox"? If you could help me with figuring this out, that'd be great and this issue would be fixed (I hope). I am just learning about Sinon and it isn't that clear to me either.

[dignifiedquire]

@Moumi your best bet is to use an e2e test (see test/e2e) which can specify a browser type and does a full karma run and checks the output.

[Moumi]

I managed to create a fix and two e2e tests for it. I will provide a PR this evening for it.