The default cabal config file specifies some directories explicitly, but not all, nor none.

[phadej]

E.g. I can see (on a fresh machine, after cabal update):

-- store-dir:
-- active-repositories:
-- local-no-index-repo:
remote-repo-cache: /home/phadej/.cache/cabal/packages
-- logs-dir: /home/phadej/.cache/cabal/logs
...
build-summary: /home/phadej/.cache/cabal/logs/build.log

I don't understand the reasoning why remote-repo-cache is explicitly specified, but store-dir and logs-dir aren't.

I'd expect all or none.

[phadej]

I'd also welcome that if the field is commented out (like store-dir), it still has its default value written (like logs-dir has).