Running metadata_add_source_doi the first time reveals missing rcrossref package

[hrlai]

Hi there, thanks for such a great package.

Just to report running the function metadata_add_source_doi the first time, I got

Error in loadNamespace(x) : there is no package called ‘rcrossref’

This went away after installing rcrossref. Might need to add it to the imports/dependencies?

[ehwenk]

@dfalster I just checked the DESCRIPTION file and rcrossref is listed under Suggests. Does it need to be under Imports instead? It is used in setup.R, the function starting line 661, and also in tests.

[ehwenk]

@hrlai Thanks for pointing this out to us! And for using the traits.build package.

[dfalster]

We could do include in either Suggests or Imports.

it was listed as Suggests because this functionality is optional. It's not needed for essential operations of the package (compiling a database). So we reduce the dependencies by listing as Suggests. The cost of that approach is that this warning happens. Other optional packages are treated similarly.