[Nix-dev] changing libstore to store packages as name-hash instead of hash-name

[Erick Tryzelaar]

so i wanted to propose a change to libstore. a long time ago when I
first found nix, I found that since nix stores directories as
hash-name, it's very difficult to see what's actually installed since
things are sorted by the hash first, not the package name. So I
finally looked at the code and it looks like it'd be a pretty simple
to change this. It looks like we could do this by changing this
function in src/libstore/store-api.cc:

Path makeStorePath(const string & type,
    const Hash & hash, const string & suffix)
{
    /* e.g., "source:sha256:1abc...:/nix/store:foo.tar.gz" */
    string s = type + ":sha256:" + printHash(hash) + ":"
        + nixStore + ":" + suffix;

    checkStoreName(suffix);

    return nixStore + "/"
        + printHash32(compressHash(hashString(htSHA256, s), 20))
        + "-" + suffix;
}


To this:


Path makeStorePath(const string & type,
    const Hash & hash, const string & prefix)
{
    /* e.g., "source:sha256:1abc...:/nix/store:foo.tar.gz" */
    string s = type + ":sha256:" + printHash(hash) + ":"
        + nixStore + ":" + suffix;

    checkStoreName(suffix);

    return nixStore + "/"
        + prefix + "-"
        + printHash32(compressHash(hashString(htSHA256, s), 20))
}


So would others be interested in this this change (and everything else
that would need fixing that this would break)? It'd obviously wouldn't
be backwards compatible, but it could make things a little bit more
explorable.