ofborg relies on the behavior that existed prior to
1c00bf3948, where evaluation would
immediately abort due to a missing argument (whether it be an aliased
package when `allowAliases = false;` or a typo'd or otherwise
nonexistent package).
If `callPackageWith` `throw`s instead of `abort`s, the following
`nix-env` invocation does not fail fast but instead silently skips the
attribute (assuming there is a package that has an aliased package in
its `autoArgs`):
$ nix-env -qa --json --file . --arg config '{ allowAliases = false; }' &>/dev/null
$ echo $?
0
This does change the error output when there is a missing package (for
any of the reasons mentioned above), though. Before this change, the
errors looked like this:
$ nix-build -A hello --arg config '{ allowAliases = false; }'
error:
… while calling the 'throw' builtin
at /home/vin/workspace/vcs/nixpkgs/master/lib/customisation.nix:179:65:
178|
179| in if missingArgs == [] then makeOverridable f allArgs else throw error;
| ^
180|
error: Function called without required argument "bash_5" at /home/vin/workspace/vcs/nixpkgs/master/pkgs/applications/misc/hello/default.nix:8, did you mean "bash" or "bashdb"?
And the errors now look like this:
$ nix-build -A hello --arg config '{ allowAliases = false; }'
error:
… while calling the 'abort' builtin
at /home/vin/workspace/vcs/nixpkgs/master/lib/customisation.nix:179:65:
178|
179| in if missingArgs == [] then makeOverridable f allArgs else abort error;
| ^
180|
error: evaluation aborted with the following error message: 'Function called without required argument "bash_5" at /home/vin/workspace/vcs/nixpkgs/master/pkgs/applications/misc/hello/default.nix:8, did you mean "bash" or "bashdb"?'