Rd deparser has serious bugs in R < 4.3

[aitap]

The package depends on as.character.Rd(deparse = TRUE) to work correctly. Prior to version 4.3.0, the deparser had serious bugs:

r"[\ifelse{latex}{\out{\\LaTeX}}{non-LaTeX}]" |>
 textConnection(name = 'foo') |>
 tools::parse_Rd(fragment = TRUE) |>
 as.character(deparse = TRUE) |>
 paste(collapse = '') |> cat()
# \ifelse{{latex}{\out{\\LaTeX}}{non-LaTeX}}

If the translator (or the user: both rely on rd_flatten → to_text) is running an LTS distro (Debian stable / Ubuntu 20.04 LTS, 22.04 LTS), their current version of R may be older than 4.3 (4.2.2, 3.6.3, 4.1.2, respectively). Let's mark the dependency of the package on the less buggy behaviour of the deparser, so that the translated Rd markup would not be invalid.

[eliocamp]

Thanks for the heads up.