Apply 'stdout' and 'conditions' settings also on loaded 'packages'

[HenrikBengtsson]

Adopted from #787 (comment):

Argument conditions does not apply to packages attached via the packages argument, e.g.

library(future)
f <- future(42, packages = "mclust", conditions = structure("condition", exclude = "packageStartupMessage"))
v <- value(f)
print(v)

This outputs:

                   __           __ 
   ____ ___  _____/ /_  _______/ /_
  / __ `__ \/ ___/ / / / / ___/ __/
 / / / / / / /__/ / /_/ (__  ) /_  
/_/ /_/ /_/\___/_/\__,_/____/\__/   version 6.1.1
Type 'citation("mclust")' for citing this R package in publications.

[1] 42

In constrast, conditions applies during the evaluation of the future expression, i.e.

library(future)
f <- future({
  mclust::map ## loads 'mclust'
  library(mclust) ## just to prove it works when package is attached too
  42
}, conditions = structure("condition", exclude = "packageStartupMessage"))
v <- value(f)
print(v)

This only outputs:

[1] 42

The solution is to make sure that conditions are also handled during the startup phase of the evaluation of the future.

UPDATE +30 mins: Added library(mclust) just to clarify that it also works when the package is attached.

[HenrikBengtsson]

This has been implemented in the next release of future.