Logrus: Allow testing of calls to `Fatal*`

[MrJoy]

If you were to add an ExitFunc func(int) field to the Logger struct, with a default implementation of func(int code) { os.Exit(code) }, it would become much easier to test code that calls Fatal*, by simply substituting the implementation with func(int code) { panic(...) } -- without having to resort to sub-process shenanigans that are complicated to implement and don't play well with -cover. Is this something you would be willing to implement / accept a PR for?

[dgsb]

That would be indeed very useful, such a PR would be very welcome.
Be careful that the implementation behaviour must be backward compatible.

[caalberts]

I'd like to give this a try

[dgsb]

Hi @caalberts, your contributions will be welcome.

[caalberts]

I raised a PR on this, do let me know if there is any concern.

[caalberts]

I think this can be closed

[dgsb]

Indeed, thanks again for your contribution.