Travis CI cannot find packages in the pkg-config search path

Question

I've recently started encountering the same errors on my various R packages updated after mid-December on Travis-CI (https://travis-ci.org/TGuillerme/). This is specially weird since for the three concerned packages, the changes were not any code change (only comments changes) but Travis-CI seems now not able to install some packages (namely magick and libgit2) using a pretty simple .yml file runing the package and codecov for coverage:

language: r
warnings_are_errors: false

branches:
  only:
    - master
    - release
  except:
    - CRAN

# Code coverage
r_packages:
  - covr

after_success:
- Rscript -e 'library(covr); codecov(token = "5f041826-63f1-47fa-b4a8-9a32633f47fa")'

The error I get in this case (although it varies with the different packages) is with the magick package:

** package ‘magick’ successfully unpacked and MD5 sums checked
Package Magick++ was not found in the pkg-config search path.
Perhaps you should add the directory containing `Magick++.pc'
to the PKG_CONFIG_PATH environment variable
No package 'Magick++' found
Using PKG_CFLAGS=
Using PKG_LIBS=-lMagick++-6.Q16

line 2625-2631

Along with one suspicious message prior to this:

Unable to find the libgit2 library on this system. Building 'git2r'
using the bundled source of the libgit2 library.

line 1563-1564

Is there something obvious that I am missing? Is there a way to force Travis-CI to automatically install the the errored packages?

Again, this is specially weird to me since the running code changes committed do not differ since last build running without errors.

Answer 1

I have been able to fix similar issues by installing packages from their binaries.

The following might help in the .travis.yml:

r_binary_packages:
    - libgit2
    - magick