Today I Learned: Packaging bash-completion files

Today I ran into this kind of problem for the first time: a package I needed to build installed a bash completion file, and the destination for it was determined by pkg-config. Depending on the system, it would most likely end up in /usr/share/bash-completion/completions/ or /etc/bash_completion.d/.

How to write the spec file to handle this dichotomy? Turns out it is not that complicated.

Drop this at the top of spec file and then use %{compdir} in the %files section. Solved.

%define compdir %(pkg-config --variable=completionsdir bash-completion)
%if "%{compdir}" == ""
%define compdir "/etc/bash_completion.d"
%endif

The real gotcha is that the %files section must install the parent of this directory, otherwise the builds will fail with error about two files on one line.