Incorrect error message when unzip fails

[jeroen]

On a Fedora box I was getting:

> devtools::install_github("plyr")
Installing github repo plyr/master from hadley
Downloading master.zip from https://github.com/hadley/plyr/archive/master.zip
Installing package from /tmp/RtmpLKWL1L/master.zip
arguments 'minimized' and 'invisible' are for Windows only
Error: Does not appear to be an R package (no DESCRIPTION)

The problem turned out to be:

> getOption("unzip")
[1] "/usr/bin/unzip"
> file.exists(getOption("unzip"))
[1] FALSE

Would be nice if devtools had a way to check for successful decompress.

[hadley]

I'm pretty sure that should do the trick - let me know if you still have problems.