Rewrite of how to count threads used by current future plan.

[Lenostatos]

New commit directly to master for PR #418.

[Jean-Romain]

Thanks

[Lenostatos]

You're welcome :)

I didn't know if and how to add a commit to master to the same PR, so I created a new one. I hope this is ok.

I also slightly tweaked the conditions for core counts and localhost vectors to be more meaningful:

# Numeric workers argument
# previous condition:
if (length(workers_arg) == 1L &&
    is.numeric(workers_arg) &&
    !is.na(workers_arg) &&
    workers_arg >= 0)
{ ...
# current PR:
if (is.numeric(workers_arg) &&
    length(workers_arg) == 1L &&
    !is.na(workers_arg) &&
    workers_arg >= 1)
{ ...


# Character vector of localhosts as workers argument
# previous condition:
if (length(workers_arg) >= 1L &&
    is.character(workers_arg) &&
    all(workers_arg %in% localhosts))
{ ...
# current PR:
if (is.character(workers_arg) &&
    length(workers_arg) >= 1L &&
    all(!is.na(workers_arg)) &&
    all(workers_arg %in% localhosts))
{ ...

[Jean-Romain]

I didn't know if and how to add a commit to master to the same PR, so I created a new one. I hope this is ok.

Me neither. I think I could have done that myself in command line with git locally. Anyway it worked.

I also slightly tweaked the conditions for core counts and localhost vectors to be more meaningful:

It seems better indeed.