assert_is_rstudio_current(severity = getOption("assertive.severity", "stop"))
is_rstudio_current()"stop", "warning", "message", or "none".is_rstudio_current returns TRUE or FALSE, and
assert_is_rstudio_current throws an error in the event of an out of
date RStudio. Non-RStudio IDEs throw an error.
downloadUpdateInfo
function from
https://github.com/rstudio/rstudio/blob/master/src/cpp/session/modules/SessionUpdates.R
where the string for the OS is described in beginUpdateCheck from
https://github.com/rstudio/rstudio/blob/master/src/cpp/session/modules/SessionUpdates.cpp
is_rstudio, is_rstudio_desktop