Been having a difficult time fixing the two remaining test suite failures when run on a FAT filesystem.
On Friday, I got quite lost trying to understand the first failure. At first I thought it had something to do with queued git staging commands not being run in the right git environment when git-annex is using a different index file or work tree. I did find and fix a potential bug in that area. It might be that some reports long ago of git-annex branch files getting written to the master branch was caused by that. But, fixing it did not help with the test suite failure at hand.
Today, I quickly found the actual cause of the first failure. Of course, it had nothing to do with queued git commands at all, and was a simple fix in the end.
But, I've been staring at the second failure for hours and am not much wiser. All I know is, an invalid tree object gets generated by the adjusted branch code that contains some files more than once. (git gets very confused when a repository contains such tree objects; if you wanted to break a git repository, getting such trees into it might be a good way. cough) This invalid tree object seems to be caused by the basis ref for the adjusted branch diverging somehow from the adjusted branch itself. I have not been able to determine why or how the basis ref can diverge like that.
Also, this failure is somewhat indeterminite, doesn't always occur and reordering the tests in the test suite can hide it. Weird.
Well, hopefully looking at it again later with fresh eyes will help.