Re: [PATCH] merge: --ff-one-only to apply FF if commit is one

> Strictly speaking, the log message on a merge commit serves two
> purposes, one is to summarize commit(s) on the side branch that gets
> merged with the merge, and as you said above, it is not needed when
> merging a topic with just one commit.  But the other is to justify
> why the topic suits the objective of the line of history (which is
> needed even when merging a single commit topic---imagine a commit
> that is not incorrect per-se.  It may or may not be suitable for the
> maintenance track, and a merge commit of such a commit into the
> track can explain if/how the commit being merged is maint-worthy).

>> The point at which you use such a merge feature is when you are already
>> happy with the pull request (or patch series or whatever else). And then
>> you (according to this strategy) prefer to avoid merge commits for
>> single-commit pull requests.
>
> But that argues against the "--ff-one-only" option, doesn't it?
>
> If you looked at the side branch before you decide to merge it, you
> know if the topic has only one commit (in which case you decide not
> to use "--no-ff"), or if the topic consists of multiple commits (in
> which case you decide to use "--no-ff").  And the only effect to
> have the "--ff-one-only" option is to allow you *not* to look at
> what is on the side branch.