Hi Chris, Christopher Baines <m...@cbaines.net> skribis:
> I believe that the direnv package has encountered an issue with the > gnu-build-system [1]. > > 1: https://issues.guix.info/issue/35386 > > Due to the combination of the 'setup-go-environment phase from the > go-build-system, and the 'unpack phase of the gnu-build-system, there > are two directories to be considered by first-subdirectory when called > from the unpack phase. > > It seems from direnv that this either consistently, with the package > working on one machine, or failing consistently on another. > > To avoid issues like this in the future, I think it would be good to > have first-subdirectory raise an error if it's behaviour could be > non-deterministic. ‘file-system-fold’ is just a wrapper around ‘readdir’ so the order in which it sees directory entries is non-deterministic. What about writing it like this: (define (first-subdirectory directory) "Return the file name of the first sub-directory of DIRECTORY." (match (scandir directory (lambda (file) (and (not (member file '("." ".."))) (file-is-directory? (string-append directory "/" file))))) ((first . _) first))) The result will be deterministic since ‘scandir’ sorts entries. Thanks, Ludo’.
