`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
(cherry picked from commit 46c98ae1327b7d14af1927fda971762e5ee53dfe)
Maximilian Bosch
c20fbabd9b