[Nix-dev] fetchgit - why sha256 protection?

[Marc Weber]

Isn't it enough to depend on the git's hash value, eg

  fetchgit { git_hash = "xxx"; url = "yyy"; }

Is compromising a git repository (even using shallow clones) that much
easier than compromising a .tar.* file protected by sha256?

In anyway you have to find a hash collision.

A lot of foreign tools (eg bundler for ruby) just store the url and the
hash. Packaging github like projects would be a lot easier if passing a
hash would be enough.

Marc Weber