Error using Travis CI with R package: 'roxygen2' >= 5.0.0 must be installed for this functionality

I am trying to use Travis CI with an R package (specifically this in-development package here).

When I update a repository, I get the following message (see the logs here):

Error: processing vignette 'comparing-mclust-and-mplus-output.Rmd' failed with diagnostics:
'roxygen2' >= 5.0.0 must be installed for this functionality.
Execution halted

This is consistent across two different packages--although the version of roxygen2 that I have is 6.0.1. I haven't been able to find others with this particular issue on either Stack Overflow or the roxygen2 GitHub page. I used usethis::use_travis() to set up the package for use with Travis (i.e., add travis.yml file.

Any ideas about how to address this?

Solution

So I believe the problem you have is with your DESCRIPTION file. Travis will install all package dependencies before trying to build the package / vignettes, so the version you have installed locally is of no consequence.

Rather, you need to be sure that roxygen2 is a dependency of your package (probably only needed in Suggests if it is necessary to build but not use your package). So adding:

Suggests: 
  roxygen2

To your DESCRIPTION file should fix the issue!