apply --allow-overlap: fix a corner case

Yes, yes, this is supposed to be only a band-aid option for `git add -p` not Doing The Right Thing. But as long as we carry the `--allow-overlap` option, we might just as well get it right. This fixes the case where one hunk inserts a line before the first line, and is followed by a hunk whose context overlaps with the first one's and which appends a line at the end. Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Johannes Schindelin committed Dec 6, 2019 at 13:08 UTC b4bbbbd5a247e0e75d079bca591b657ec9084a46

1 file changed +10

apply.c

+10

@@ -2661,6 +2661,16 @@ static int find_pos(struct apply_state *state,

2661 unsigned long backwards, forwards, current;

2662 int backwards_lno, forwards_lno, current_lno;

2663

2664 + /*

2665 + * When running with --allow-overlap, it is possible that a hunk is

2666 + * seen that pretends to start at the beginning (but no longer does),

2667 + * and that *still* needs to match the end. So trust `match_end` more

2668 + * than `match_beginning`.

2669 + */

2670 + if (state->allow_overlap && match_beginning && match_end &&

2671 + img->nr - preimage->nr != 0)

2672 + match_beginning = 0;

2673 +

2674 /*

2675 * If match_beginning or match_end is specified, there is no

2676 * point starting from a wrong line that will never match and