request: allow passing -X <strategy-option> to git checkout <path> to auto-solve merge conflicts

> That's my answer =)
>
> I think adding a merge strategy option to checkout might be useful
>
> On Mon, Dec 27, 2021 at 4:49 PM Andrey Butirsky <butirsky@gmail.com> wrote:
>> Hi, stumbling upon this again and again, so decided to write finally,
>>
>> while in conflicting state, the only thing we can do to auto-pick one or
>> another side of conflict is passing --ours/--theirs option to git-checkout:
>> git checkout --ours/--theirs <path>
>>
>> The problem is - it doesn't actually do a _merge_, i.e. you lose all
>> non-conflicted changes.
>>
>> There is no easy way to solve that currently without third-party tools.
>>
>> This link illustrates it:
>> https://stackoverflow.com/a/68498101/1063363
>>
>> Proposal:
>> Shell we add -X <strategy-option> to git checkout <path> to allow it do
>> a merge and _actually solve_ merge conflicts?
>> That would be in-pair with other commands taking the option already:
>> git-merge, git-rebase, (etc.?)
>>

> merge: teach -Xours/-Xtheirs to binary ll-merge driver
>
> The (discouraged) -Xours/-Xtheirs modes of merge are supposed to
> give a quick and dirty way to come up with a random mixture of
> cleanly merged parts and punted conflict resolution to take contents
> from one side in conflicting parts.  These options however were only
> passed down to the low level merge driver for text.

>
> > On Tue, Dec 28, 2021 at 9:44 PM Andrey Butirsky <butirsky@gmail.com> wrote:
> > Thanks Erik, please post your further replies to the mailing list so
> > others could see it also.
>
> Mea culpa
>
> > On a topic,
> > I'm not familiar with Git code-base so don't know if it even possible in
> > it's current architecture..
>
> It looks like
> builtin/checkout.c checkout_merged
> is responsible and calls
> ll-merge.c ll_merge
>
> I think other commands that allow merging strategies may use other
> "merge drivers".
>
> From commit a944af1d86e6171d68ed2a3aa67b1d68f00e1fe8
> > merge: teach -Xours/-Xtheirs to binary ll-merge driver
> >
> > The (discouraged) -Xours/-Xtheirs modes of merge are supposed to
> > give a quick and dirty way to come up with a random mixture of
> > cleanly merged parts and punted conflict resolution to take contents
> > from one side in conflicting parts.  These options however were only
> > passed down to the low level merge driver for text.
>
> It looks possible.
> But perhaps the sentiment is that it's not adviceable?

> On a tangent, you can set up your own merge tools.
>
> So in git config you can add something like:
>
> [mergetool "both"]
> cmd = "sed -i -e '/^<<<<<<<$/d' -e '/^=======$/d' -e '/^>>>>>>>$/d' -- $MERGED"
>
> and call it with git mergetool --tool=both