Re: [PATCH] for-each-ref: Always check stat_tracking_info()'s return value.

> The code handling %(upstream:track) and %(upstream:trackshort) assumed
> it always had a valid branch that had been sanitized earlier in
> populate_value(), and thus did not check the return value of the call to
> stat_tracking_info().
>
> While there is indeed some sanitization code that basically corresponds
> to stat_tracking_info() returning 0 (no base branch set), the function
> can also return -1 when the base branch did exist but has since then
> been deleted.
>
> In this case, num_ours and num_theirs had undefined values and a call to
> `git for-each-ref --format="%(upstream:track)"` could print spurious
> values such as
>
>   [behind -111794512]
>   [ahead 38881640, behind 5103867]
>
> even for repositories with one single commit.
>
> We now properly verify stat_tracking_info()'s return value and do not
> print anything if it returns -1. This behavior also matches the
> documentation ("has no effect if the ref does not have tracking
> information associated with it").
>
> Signed-off-by: Raphael Kubo da Costa <raphael.kubo.da.costa@intel.com>
> ---
> diff --git a/t/t6300-for-each-ref.sh b/t/t6300-for-each-ref.sh
> index bda354c..775c255 100755
> --- a/t/t6300-for-each-ref.sh
> +++ b/t/t6300-for-each-ref.sh
> @@ -335,6 +335,21 @@ test_expect_success 'Check that :track[short] cannot be used with other atoms' '
>  '
>
>  cat >expected <<EOF
> +
> +
> +EOF
> +
> +test_expect_success 'Check that :track[short] works when upstream is gone' '
> +       git branch --track to_delete master &&
> +       git branch --track parent_gone to_delete &&
> +       git branch -D to_delete &&
> +       git for-each-ref --format="%(upstream:track)" refs/heads/parent_gone >actual &&
> +       git for-each-ref --format="%(upstream:trackshort)" refs/heads/parent_gone >>actual &&

> +       test_cmp expected actual
> +'
> +
> +cat >expected <<EOF
>  $(git rev-parse --short HEAD)
>  EOF
>
> --
> 2.1.4