Since 108debef6f we allow a
`url`-attribute for the `github`-fetcher to fetch tarballs from
self-hosted `gitlab`/`github` instances.
However it's not used when defining e.g. a flake-input
foobar = {
type = "github";
url = "gitlab.myserver";
/* ... */
}
and breaks with an evaluation-error:
error: --- Error --------------------------------------nix
unsupported input attribute 'url'
(use '--show-trace' to show detailed location information)
This patch allows flake-inputs to be fetched from self-hosted instances
as well.