RStudio uses incorrect 'editor' option definition

[kevinushey]

Originally from tidyverse/reprex#204.

We define this function here:

rstudio/src/cpp/session/modules/SessionEnvironment.R

Line 379 in 8af7304

options(editor = function(name, file, title) {

but utils::file.edit() calls the function as:

> utils::file.edit
function (..., title = file, editor = getOption("editor"), fileEncoding = "")
{
    file <- path.expand(c(...))
    title <- rep_len(as.character(title), length(file))
    if (nzchar(fileEncoding) && fileEncoding != "native.enc") {
        tfile <- file
        for (i in seq_along(file)) {
            tfile <- tempfile()
            con <- file(file[i], encoding = fileEncoding)
            writeLines(readLines(con), tfile)
            close(con)
            file[i] <- tfile
        }
    }
    if (is.function(editor))
        invisible(editor(file = file, title = title))
    else invisible(.External2(C_fileedit, file, title, editor))
}
<bytecode: 0x7f8e2caeac78>

That is, there is no argument 'name'. This implies that calls to e.g.

utils::file.edit(tempfile())

can fail. Surprisingly, it only fails on Windows; it does succeed on non-Windows.