As dev, I want create_dependencies_file() to have a parameter install_if_missing

[MurielleDelmotte]

create_dependencies_file() uses DESCRIPTION as source of information. _Note that DESCRIPTION file can be auto-fill using find_remotes()

Criteria of success

• [x] create_dependencies_file() to have an ~install_if_missing~ install_only_if_missing parameter

• From a DESCRIPTION file such as:

  • [ ] If install_if_missing = FALSE (by default) , the installation instructions don't check, beforehand, if the packages are missing

• [ ] If install_if_missing = TRUE (by default) , the installation instructions check, beforehand, if the packages are missing

Technicals

• [ ] Add a parameter install_if_missing = FALSE that will add a if(requireNamespace(quietly = TRUE)) {} before each install if the parameter is TRUE

  # Remotes ----
  if(requireNamespace("remotes", quietly = TRUE)) {install.packages("remotes")}
  if(requireNamespace("mylocalpackage", quietly = TRUE)) {remotes::install_github('local::mylocalpackage')}
  ...

• I think that listing all packages with their version with install_version() is not reliable, because of versions of sub-dependencies. I would recommend to redirect users to {renv} and create the Dockerfile using {renv}.

• It would be interesting to create the "socle" part of {dockerfiler} that install all deps, even without {renv}

[VincentGuyader]

ok, some improvment were made this the screenshot