'guix build --debug=5 -S test-repo' build logs shows that the problem
sits in 'guix-build' procedure from 'guix/scripts/build.scm'. 'drv' local
variable is initialized by '(options->derivations store opts)' at line 762
to a list '("/gnu/store/...-test-repo-checkout") containing store
path to the true test-repo checkout (i.e. what is desired to be the output
of 'guix build -S'), and not a file with .drv extension or derivation object.
But the subsequent code in 'guix-build' (calls to 'show-derivation-outputs' and
'derivation->output-paths' procedures) supposes that 'drv' is a list of
derivation objects or .drv files, which leads to an error.Regards, Nigko
