Re: A rebase regression in Git 2.18.0

> On 28. Aug 2018, at 15:33, Johannes Schindelin <Johannes.Schindelin@gmx.de> wrote:
> 
> Hi,
> 
> On Tue, 28 Aug 2018, Ævar Arnfjörð Bjarmason wrote:
> 
>> On Tue, Aug 28 2018, Nikolay Kasyanov wrote:
>> 
>>> I’ve found something that may be a regression in git rebase implementation in 2.18.0.
>>> First I spotted it on macOS but I can also confirm it happening on Linux.
>>> Git 2.19.0.rc0.48.gb9dfa238d is affected too.
>>> 
>>> In order to trigger it, a repo layout similar to the following is required:
>>> 
>>> files/
>>> 	file1
>>> 	file2
>>> 	file3
>>> 	file4
>>> 	file5
>>> project
>>> 
>>> Let’s call this state baseline. Then, in a branch, let’s edit project file and move file3 to nested/files subdirectory, here’s the final layout:
>>> 
>>> files/
>>> 	file1
>>> 	file2
>>> 	file4
>>> 	file5
>>> nested/
>>> 	files/
>>> 		file3
>>> project
>>> 
>>> Let’s get back to master and also edit project file to cause a conflict. After that trying to rebase the branch upon master will cause the following git status output:
>>> 
>>> rebase in progress; onto baf8d2a
>>> You are currently rebasing branch 'branch' on 'baf8d2a'.
>>>  (fix conflicts and then run "git rebase --continue")
>>>  (use "git rebase --skip" to skip this patch)
>>>  (use "git rebase --abort" to check out the original branch)
>>> 
>>> Changes to be committed:
>>>  (use "git reset HEAD <file>..." to unstage)
>>> 
>>> 	renamed:    files/file1 -> nested/files/file1
>>> 	renamed:    files/file2 -> nested/files/file2
>>> 	renamed:    files/file3 -> nested/files/file3
>>> 	renamed:    files/file4 -> nested/files/file4
>>> 	renamed:    files/file5 -> nested/files/file5
>>> 
>>> Unmerged paths:
>>>  (use "git reset HEAD <file>..." to unstage)
>>>  (use "git add <file>..." to mark resolution)
>>> 
>>> 	both modified:   project
>>> 
>>> All renames except file3 are invalid and shouldn’t be here.
>>> Here’s how the output looks like produced by an older Git version (git version 2.15.1):
>>> 
>>> rebase in progress; onto baf8d2a
>>> You are currently rebasing branch 'branch' on 'baf8d2a'.
>>>  (fix conflicts and then run "git rebase --continue")
>>>  (use "git rebase --skip" to skip this patch)
>>>  (use "git rebase --abort" to check out the original branch)
>>> 
>>> Changes to be committed:
>>>  (use "git reset HEAD <file>..." to unstage)
>>> 
>>> 	renamed:    files/file3 -> nested/files/file3
>>> 
>>> Unmerged paths:
>>>  (use "git reset HEAD <file>..." to unstage)
>>>  (use "git add <file>..." to mark resolution)
>>> 
>>> 	both modified:   project
>>> 
>>> Here’s a ready-to-use repository: https://github.com/nikolaykasyanov/git-rebase-bug.
>> 
>> Thanks for the test case. This bisects down to 9c0743fe1e
>> ("merge-recursive: apply necessary modifications for directory renames",
>> 2018-04-19) first released as part of 2.18.0.
>> 
>> I have not dug to see if the behavior change is desired or not, that
>> commit changed the results of a bunch of test cases, maybe it was
>> intended. Elijah?
> 
> I think this was already mentioned before, in a different mail thread:
> have you tried whether `git rebase -m` fixes that behavior?
> 
> Ciao,
> Johannes