Re: [PATCH] subtree: ignore merge.ff setting

From: Junio C Hamano <gitster@pobox.com>
Date: Nov 14, 2021, 18:38 UTC
Message-ID: <xmqqee7ilh0f.fsf@gitster.g>
In-Reply-To: <pull.1139.git.git.1636902454370.gitgitgadget@gmail.com>

"Thomas Koutcher via GitGitGadget" <gitgitgadget@gmail.com> writes:

Show 5 quoted lines

> From: Thomas Koutcher <thomas.koutcher@online.fr>
>
> When `merge.ff` is set to `only` in .gitconfig, `git subtree pull` will
> fail with error `fatal: Not possible to fast-forward, aborting.`. This
> fix ignores the `merge.ff` setting when using `git merge` within subtree.

The first sentence is understandasble as a statement of fact. There is a small logic gap between it and the second sentence, calling the change in the patch a "fix". I think ", but the command does want to make merges in these places." added after the first sentence would fix it.

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> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1139%2Fkoutcher%2Fsubtree-merge-ff-fix-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1139/koutcher/subtree-merge-ff-fix-v1
> Pull-Request: https://github.com/git/git/pull/1139
>
>  contrib/subtree/git-subtree.sh | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh
> index 7f767b5c38f..de918d9fb05 100755
> --- a/contrib/subtree/git-subtree.sh
> +++ b/contrib/subtree/git-subtree.sh
> @@ -976,10 +976,10 @@ cmd_merge () {
>  
>  	if test -n "$arg_addmerge_message"
>  	then
> -		git merge -Xsubtree="$arg_prefix" \
> +		git -c merge.ff= merge -Xsubtree="$arg_prefix" \
>  			--message="$arg_addmerge_message" "$rev"
>  	else
> -		git merge -Xsubtree="$arg_prefix" $rev
> +		git -c merge.ff= merge -Xsubtree="$arg_prefix" $rev

And the natural way to override what is configured is to pass a countermanding command line option, e.g. "git merge --ff" (or "git merge --no-ff", if it wants to always create a merge even when taking a change that is a descendant---I do not know the need of "git subtree" well enough to tell), and that is easier to read than "git -c ...".