DESCRIPTION on mounted folders

[gdkrmr]

Situation:

Ubuntu 16.04, latest R and roxygen2 from CRAN and a Package in a folder mounted with sftp via gnome virtual file system

A call to roxygen2::document() produces a garbage DESCRIPTION file: instead of appending it overwrites from the beginning. The problem is R and writing to connections

 for(i in 1:10){cat(i, file = "/mounted/folder/test2", append = TRUE)}

gives a file that reads 10 and not 1 2 ... 10

Solution, open the file only once:

assignInNamespace(
    "write.description",
    function(desc, file = "") {
        con <- if(file != ""){
            file(file, "w")
        } else {
            ""
        }

        mapply(roxygen2:::cat.description, names(desc), desc, MoreArgs = list(file = con))

        if(inherits(con, "connection")) close(con)

        invisible()
    },
    "roxygen2"
)

The post that helped me with this can be found here:
https://stackoverflow.com/questions/24927041/r-writeappend-true-overwrites-file-contents

[gdkrmr]

I did some more checking with

for(i in 1:10){cat(i, file = "/mounted/folder/test2", append = TRUE)}

• A mapped network drive on Windows 7 and R 3.2.5 works fine.
• A samba share on a Mac works fine.
• A samba share on Ubuntu 16.04 works fine.
• An sftp share on Ubuntu 16.04 does not work, replicated on 2 machines.

[hadley]

This is a bug with R — can you please report on R-devel?

[eddelbuettel]

Nope.

(r-devel sent him to r-sig-debian where I just conjectured that R has nothing to do with this. The 'append' property is not being honoured by the sftp-based filesystem, which is not the fault of the client.)

I would suggest to work around it. Create the DESCRIPTION file somewhere else -- say in /tmp where the write and append semantics work. Then copy the final file.

[gdkrmr]

you can change the roxygen2:::write.description as above and it works fine.
If anyone should ever come across the same isse, here is how I resolved it for me:

I created a file named .Rprofile in the package root folder (which is the working directory for the R process) with the following content:

.First <- function() {
    requireNamespace("roxygen2")
    unlockBinding("write.description", asNamespace("roxygen2"))
    assign(
        "write.description",
        function(desc, file = "") {
            con <- if(file != "") file(file, "w") else ""

            mapply(roxygen2:::cat.description, names(desc), desc, MoreArgs = list(file = con))

            if(con != "") close(con)

            invisible()
        },
        envir = asNamespace("roxygen2")
    )
    lockBinding("write.description", asNamespace("roxygen2"))
}

[hadley]

This will not work in the future because write.description has been removed. But I don't think the functions from the desc package will have the same problem.