Missing dependency on fs

[mmokrejs]

Hi,
it seems the dependency on fs is not defined. Thank you.

* installing *source* package 'treeio' ...
** package 'treeio' successfully unpacked and MD5 sums checked
staged installation is only possible with locking
** using non-staged installation
** R
** inst
** byte-compile and prepare package for lazy loading
Error in loadNamespace(j <- i[[1L]], c(lib.loc, .libPaths()), versionCheck = vI[[j]]) : 
  there is no package called 'fs'
Calls: <Anonymous> ... loadNamespace -> withRestarts -> withOneRestart -> doWithOneRestart
Execution halted
ERROR: lazy loading failed for package 'treeio'
* removing '/usr/lib64/R/library/treeio'
ERROR: dependency 'treeio' is not available for package 'ggtree'
* removing '/usr/lib64/R/library/ggtree'

The downloaded source packages are in
	'/tmp/RtmpfbLB80/downloaded_packages'
Updating HTML index of packages in '.Library'
Making 'packages.html' ... done
Warning messages:
1: In install.packages(...) :
  installation of package 'treeio' had non-zero exit status
2: In install.packages(...) :
  installation of package 'ggtree' had non-zero exit status
>