`pkgs.fetchgit` uses `fetchSubmodules = true;` by default, however
`nix-prefetch-git` doesn't. This means that hashes for a Git repository
with fetched submodules will be wrong in `yarn.nix`.
Considering that this got unnoticed before, it seems as if this case is
an exception to a certain degree.
An exemplary problem is the last `hedgedoc` update[1] where
`js-sequence-diagrams` - a Git repo with submodules - from upstream's
package.json caused a hash mismatch. This got unnoticed because
`nix-build --check` doesn't seem to reveal these issues for fixed-output
derivations.
[1] https://github.com/NixOS/nixpkgs/pull/139238
The way I see it, there's no point in the argument being there if it can't be used.
Right now its lack currently prevents a workaround for an issue I can't wrap my head around - first encountered [here](https://logs.nix.samueldr.com/nixos-dev/2019-08-28#2532857;).
@lheckemann already added it to `yarn2nix` a while ago[1], but it seems
as it was forgotten to include when adding `yarn2nix` sources to
`nixpkgs` itself.
Without this patch, you cannot add dependencies to your `package.json`
with URLs like `git://github.com/.../` as building the expression would
fail like this:
```
curl: (1) Protocol "git" not supported or disabled in libcurl
error: cannot download git___github.com_sstur_nodeftpd.git from any mirror
```
Co-authored-by: Linus Heckemann <git@sphalerite.org>
[1] https://github.com/nix-community/yarn2nix/pull/141
The generated yarnNix file doesn't need to be part of the mkDerivation.
And doing so prevents other platforms from reproducibly instantiating
it. With this change you can e.g. do
darwinPkgs.yarn2nix.mkYarnPackage {
# ...
yarnNix = pkgs.yarn2nix.mkYarnNix {
yarnLock = ./yarn.lock;
};
}
Which is a darwin derivation, but can still be instantiated reproducibly on Linux.