From 1.7 gb to 900 mb on 300 thousand unique reported shas.
When shas are not unique, this streams much better than before, so won't
buffer the full list before putting them into the Set and throwing away
dups. And when fsck output includes ignorable lines, especially
dangling object lines, they won't be buffered in memory at all.
Removed instance, got it all to build using fromRef. (With a few things
that really need to show something using a ref for debugging stubbed out.)
Then added back Read instance, and made Logs.View use it for serialization.
This changes the view log format.
Fixes a test case I received where a corrupted repo was repaired, but the
git-annex branch was not. The root of the problem was that the
MissingObject returned by the repair code was not necessarily a complete
set of all objects that might have been deleted during the repair.
So, stop trying to return that at all, and instead make the index file
checking code explicitly verify that each object the index uses is present.
Oh, git, you made this so hard. Not determining if a branch pointed to some
corrupt object, that was easy, but dealing with corrupt branches using git
plumbing is a PITA.
