pull: should be noop when already-up-to-date

[erwinv]

The already-up-to-date pull bug was fixed for --ff-only but it did not
include the case where --ff or --ff-only are not specified. This updates
the --ff-only fix to include the case where --ff or --ff-only are not
specified in command line flags or config.

Signed-off-by: Erwin Villejo erwin.villejo@gmail.com

[gitgitgadget]

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[dscho]

/allow

[gitgitgadget]

User erwinv is now allowed to use GitGitGadget.

[erwinv]

/preview

[gitgitgadget]

Preview email sent as pull.1078.git.1637135013965.gitgitgadget@gmail.com

[erwinv]

/submit

[gitgitgadget]

Submitted as pull.1078.git.1637135750674.gitgitgadget@gmail.com

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[gitgitgadget]

On the Git mailing list, Junio C Hamano wrote (reply to this):

"Erwin Villejo via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: Erwin Villejo <erwin.villejo@gmail.com>
>
> The already-up-to-date pull bug was fixed for --ff-only but it did not
> include the case where --ff or --ff-only are not specified. This updates
> the --ff-only fix to include the case where --ff or --ff-only are not
> specified in command line flags or config.
>
> Signed-off-by: Erwin Villejo <erwin.villejo@gmail.com>
> ---

> @@ -1102,15 +1103,16 @@ int cmd_pull(int argc, const char **argv, const char *prefix)
>  	}
>  
>  	can_ff = get_can_ff(&orig_head, &merge_heads);
> +	divergent = !can_ff && !already_up_to_date(&orig_head, &merge_heads);
>  
>  	/* ff-only takes precedence over rebase */
>  	if (opt_ff && !strcmp(opt_ff, "--ff-only")) {
> -		if (!can_ff && !already_up_to_date(&orig_head, &merge_heads))
> +		if (divergent)
>  			die_ff_impossible();
>  		opt_rebase = REBASE_FALSE;
>  	}
>  	/* If no action specified and we can't fast forward, then warn. */
> -	if (!opt_ff && rebase_unspecified && !can_ff) {
> +	if (!opt_ff && rebase_unspecified && divergent) {
>  		show_advice_pull_non_ff();
>  		die(_("Need to specify how to reconcile divergent branches."));
>  	}

Looks correct.  I wonder if there is a simplify these two checks,
but let's keep the original code structure for now in this step,
which is about correctness.

Will apply.  Thanks.

> diff --git a/t/t7601-merge-pull-config.sh b/t/t7601-merge-pull-config.sh
> index 6275641b9c2..bd238d89b0c 100755
> --- a/t/t7601-merge-pull-config.sh
> +++ b/t/t7601-merge-pull-config.sh
> @@ -387,6 +387,12 @@ test_expect_success 'pull prevents non-fast-forward with "only" in pull.ff' '
>  	test_must_fail git pull . c3
>  '
>  
> +test_expect_success 'already-up-to-date pull succeeds with unspecified pull.ff' '
> +	git reset --hard c1 &&
> +	git pull . c0 &&
> +	test "$(git rev-parse HEAD)" = "$(git rev-parse c1)"
> +'
> +
>  test_expect_success 'already-up-to-date pull succeeds with "only" in pull.ff' '
>  	git reset --hard c1 &&
>  	test_config pull.ff only &&
>
> base-commit: cd3e606211bb1cf8bc57f7d76bab98cc17a150bc

[gitgitgadget]

This branch is now known as ev/pull-already-up-to-date-is-noop.

[gitgitgadget]

This patch series was integrated into seen via git@3ee877f.

[gitgitgadget]

This patch series was integrated into seen via git@7585dbe.

[gitgitgadget]

This patch series was integrated into seen via git@8ae92d8.

[gitgitgadget]

This patch series was integrated into next via git@2d8f0cd.

[gitgitgadget]

There was a status update in the "New Topics" section about the branch ev/pull-already-up-to-date-is-noop on the Git mailing list:

"git pull" with any strategy when the other side is behind us
should succeed as it is a no-op, but doesn't.

Will merge to 'master'.

[gitgitgadget]

This patch series was integrated into seen via git@b4520d1.

[gitgitgadget]

This patch series was integrated into seen via git@0f2140f.

[gitgitgadget]

This patch series was integrated into next via git@0f2140f.

[gitgitgadget]

This patch series was integrated into master via git@0f2140f.

[gitgitgadget]

Closed via 0f2140f.

[Ark-kun]

Finally!
Thank you for fixing this issue.

The VSCode's sync feature has been completely broken for months.

Previously it worked flawlessly when the local branch is ether strictly behind or strictly ahead the remote. But at some GIT version the function started failing due to GIT errors. It still does as of GIT 2.34, but I hope this patch will make it work again..