[R-pkg-devel] Unusually long execution time for R.utils::gzip on r-devel-windows

[Stefan Mayer]

Dear list,

I tried to submit an update to my R package imagefluency, but the update does not pass the incoming checks automatically. The problem is that one of the examples takes too long to execute – but only under Windows with the development version of R (R Under development (unstable) (2024-02-15 r85925 ucrt)).

I was able to pin down the problem to using R.utils::gzip(). I created a test package that illustrates the problem: https://github.com/stm/ziptest
The package has two functions that zip a file given a file path. When using R.utils::gzip() (function `gzipit()` in the test package), I get a NOTE when checking the package using devtools::check_win_devel()

* checking examples ... [55s] NOTE
Examples with CPU (user + system) or elapsed time > 10s
       user system elapsed
gzipit 6.91  47.24   54.84

There is no issue with utils::zip() (function `zipit()` in the test package). Is this somehow a bug in R.utils::gzip(), or is there an issue with the combination of Windows and r-devel?

Best, Stefan