Don't want to try to use these remotes as key/value remotes, which will
surely fail. It only recently became possible for importtree to be set
w/o exporttree, so before this code was ok.
(cherry picked from commit 97599cb0f7f4115aa5a3e81a91ee3d1d6c52dc84)
In cd1676d604, it stopped using that to avoid surprising behavior
when the location log and remote content were out of sync.
But, it seems that may have changed some behavior users relied on as
well, and also Remote.hasKeyCheap should be faster than checking then
location log.
So, try Remote.hasKeyCheap first, and only if it does not have the key,
fall back to checking the location log. If the location log still thinks
it's present, go ahead and try to get it, so the user will see a failure
rather than silently skipping a file what whereis says is on the remote.
This does make slightly slower the case where the remote does not have
the key, and location log and Remote.hasKeyCheap agree, since it now
checks both. But only 1 stat slower.
And vice-versa, but it's better to use '/' for portability.
Notably, standardPreferredContent contains "archive/*" and that might not
match if the filename ends up coming in with the slashes the other way
around.
I do think this was a reversion, but I have not tracked back to what
version. While involving the remote config, it's not the same class of
problems that I kept having to chase down for a while after the remote
config parser reworking.
git -c was already propagated via environment, but need this for
consistency.
Also, notice it does not use gitAnnexChildProcess to run the
transferrer. So nothing is done about avoid it taking the
pid lock. It's possible that the caller is already doing something that
took the pid lock, and if so, the transferrer will certianly fail,
since it needs to take the pid lock too. This may prevent combining
annex.stalldetection with annex.pidlock, but I have not verified it's
really a problem. If it was, it seems git-annex would have to take
the pid lock when starting a transferrer, and hold it until shutdown,
or would need to take pid lock when starting to use a transferrer,
and hold it until done with a transfer and then drop it. The latter
would require starting the transferrer with pid locking disabled for the
child process, so assumes that the transferrer does not do anyting that
needs locking when not running a transfer.
MatchingKey is not the thing to use when matching on actual worktreee
files.
Fix reversion in 8.20201116 that made include= and exclude= in
preferred/required content expressions match a path relative to the current
directory, rather than the path from the top of the repository.
* Guard against running in a repo where annex.uuid is set but
annex.version is set, or vice-versa.
* Avoid autoinit when a repo does not have annex.version or annex.uuid
set, but has a git-annex objects directory, suggesting it was used
by git-annex before.
