Enable travis CI to check for package dependencies - r

Question

Actual question
What do I need to do in order to enable travis CI to check my package dependencies?
What I tried
I tried adding the cran argument to .travis.yml file as describe in guide on travis-ci.com.
My .travis.yml file looks like this:
language: r
warnings_are_errors: yes
sudo: required
cran: http://cran.rstudio.com
r_packages:
- covr
after_success:
- Rscript -e 'covr::codecov()'
Yet, I still get the following error:
* checking package dependencies ... ERROR
No repository set, so cyclic dependency check skipped
Session info
> sessionInfo()
R version 3.2.2 (2015-08-14)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1
locale:
[1] LC_COLLATE=German_Germany.1252 LC_CTYPE=German_Germany.1252
[3] LC_MONETARY=German_Germany.1252 LC_NUMERIC=C
[5] LC_TIME=German_Germany.1252
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] devops_0.1.2
loaded via a namespace (and not attached):
[1] magrittr_1.5 tools_3.2.2 yaml_2.1.13 memoise_0.2.1 stringi_1.0-1
[6] stringr_1.0.0 digest_0.6.8 devtools_1.9.1
Update
I found out that the error was actually cause by listing some package dependencies in Suggests: instead of Imports: section of my DESCRIPTION file (build that passed).
However, I'm still getting a note that the dependency check was skipped as no repository has been set:
* checking package dependencies ... NOTE
No repository set, so cyclic dependency check skipped
Does that mean that a dependency check has not been carried out and, if so, what do I need to change in order to make this happen?