Can't use + in inputs.*.url in flake.nix

[SnO2WMaN]

Describe the bug

Some GitHub repositories (not specifically related to Nix) have releases with tags like 0.3.0+plus, for example, which I can specify in flake.nix as inputs.foo.url = github:foo/bar/0.3.0+plus but cannot get or lock.
Likewise it will fail if + is replaced by %2B.

Expected behavior

Can fetch and lock.

nix-env --version output

nix-env (Nix) 2.8.1

[tomberek]

Potentially add a + to https://github.com/NixOS/nix/blob/master/src/libutil/url-parts.hh#L26
But this does mean the URL is no longer a valid URL. Might be preferable to ensure + is percent encoded/decoded.

A workaround for now is to use the attribute syntax (not available in CLI):

{
  inputs.s = {
    type = "github";
    owner = "tomberek";
    repo = "nix";
    ref = "tag+tag";
  };
  outputs = _: _.s;
}

[SuperSandro2000]

Does quoting make a difference here?

[tgunnoe]

Does quoting make a difference here?

No, I just tried with quotes in the non-cli schema. looks like any special characters in the URL will be fail to retrieve the proper commit.