To build binary packages on windows, Rtools (found at https://CRAN.R-project.org/bin/windows/Rtools/) needs to be on the path. The default installation process does not add it, so this script finds it (looking first on the path, then in the registry). It also checks that the version of rtools matches the version of R. has_rtools() determines if Rtools is installed, caching the results. Afterward, run rtools_path() to find out where it's installed.

## Usage

rtools_path()

has_rtools(debug = FALSE)

check_rtools(debug = FALSE)

## Arguments

debug

If TRUE, will print out extra information useful for debugging. If FALSE, it will use result cached from a previous run.

## Value

Either a visible TRUE if rtools is found, or an invisible FALSE with a diagnostic message(). As a side-effect the internal package variable rtools_path is updated to the paths to rtools binaries.

## Acknowledgements

This code borrows heavily from RStudio's code for finding Rtools. Thanks JJ!

## Examples

has_rtools()
#> [1] FALSE