On Fri, 2020-03-27 at 11:39 -0700, Elijah Newren wrote: > Hi Alban, > > On Fri, Mar 27, 2020 at 8:46 AM Alban Gruin <alban.gruin@xxxxxxxxx> > wrote: > > Hi Jan, > > > > +cc Johannes, Elijah, and Phillip. > > > > Le 27/03/2020 à 12:44, Jan Alexander Steffens (heftig) a écrit : > > > Hi, > > > > > > Since 2.26.0 a simple "git rebase" fails to fast-forward a > > > branch, reporting "error: nothing to do." > > > > > > It started to work again after removing my gitconfig. I've > > > reduced it to the following: > > > > > > git init foo; cd foo > > > git commit --allow-empty -m foo > > > git commit --allow-empty -m bar > > > git checkout -tb foo > > > git reset HEAD~ > > > git -c rebase.abbreviateCommands=true rebase > > > > > > > Thank you for reporting this bug. > > > > Since git 2.26, the default rebase backend switched from "am" to > > "merge". So, by default, a todo list is created, even if you can't > > see it. > > > > In this case, the todo list contains only a `noop', but this > > command has > > no short form, and is abbreviated with a comment mark. As there is > > no > > more commands in the list, the backend will fail with the error > > "nothing > > to do". > > > > Three approach to fix this: > > > > 1) add an abbreviation to `noop'; this is the simplest fix, and > > "n" is > > not taken. > > 2) if a command has no short form, do not abbreviate it; this is > > trivial to do, and should not break anything. > > Both sound reasonable to me. > > > A third approach would be to change the meaning of an empty buffer, > > but > > this would break some tests (at least t3404.3) and cause more > > confusion > > for users than necessary. > > Well, "error: nothing to do" probably makes sense if the user > specifies a list of empty commands or sees a list of empty commands > and agrees to pass these to the backend. But I'm not sure that > message makes sense for implicitly interactive runs as opposed to > explicitly interactive ones. Perhaps we could change the message to > just be "Already up to date" if the buffer is empty and the run is > not > explicitly interactive? Changing just the message and return code wouldn't be enough, as the empty todo results in the rebase being aborted without fast-forwarding the branch.
