[Bioc-devel] R environment variable which indicates "running in the bioc build system"?

[Paul Shannon]

My package igvR requires a web browser.  Unit tests, examples, vignette all will all fail if one is not available.

Since the bioc build system, for good reason, does not provide a web browser, I’d like to condition all browser-related code on “not executing in the bioc build system”.

Is there a way my test and example code can detect that?

I prefer not to condition on 

  if(interactive())

because in some settings (travis CI, my own development setup) non-interactive tests, using a possibly headless browser, do make sense.

Thank you -

 - Paul