Due to fetchGit not checking if rev is an ancestor of ref (there is even
a FIXME comment about it in the code), the cache repo might not have the
ref even though it has the rev. This doesn't matter when submodule =
false, but the submodule = true code blows up because it tries to fetch
the (missing) ref from the cache repo.
Fix this in the simplest way possible: fetch all refs from the local
cache repo when submodules = true.
TODO: Add tests.
The .link file is used as a lock, so I think we should put the
"submodule" attribute in there since turning on submodules creates a new
.link file path.
Having max-jobs = 32 ($NIX_USER_COUNT is hardcoded to that value) may
severely overload the machine. The nix.conf(5) manual page says max-jobs
defaults to 1, so let's use that value.
NOTE: Both max-jobs and cores are now being set to their default value,
so they can be removed alltogether.
Instead, print a message about what happened and tell the user what can
be done (run "[sudo -i] nix-channel --update nixpkgs" again at a later
time). This change allows installing Nix when you're offline.
Since the multi-user installer is so verbose, the message isn't printed
until the end.
Fixes issue #2650 ("installation without internet connection").
unpack-channel.nix fails if the tarball contains a directory named the
same as the channel:
mv: cannot move 'nixpkgs' to a subdirectory of itself, '.../nixpkgs'
This commit fixes that by not moving the directory if it already has the
correct name.
This is arguably nitpicky, but I think this new formulation is even
clearer. My thinking is that it's easier to comprehend when the
calculated hash value is displayed close to the output path. (I think it
is somewhat similar to eliminating double negatives in logic
statements.)
The formulation is inspired / copied from the OpenEmbedded build tool,
bitbake.