built-in add -p: coalesce hunks after splitting them

This is considered "the right thing to do", according to 933e44d3a0
("add -p": work-around an old laziness that does not coalesce hunks,
2011-04-06).

Note: we cannot simply modify the hunks while merging them; Once we
implement hunk editing, we will call `reassemble_patch()` whenever a
hunk is edited, therefore we must not modify the hunks (because the user
might e.g. hit `K` and change their mind whether to stage the previous
hunk).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Johannes Schindelin 2019-12-13 08:07:59 +00:00 committed by Junio C Hamano
parent 510aeca199
commit 11f2c0dae8

View File

@ -433,6 +433,55 @@ static void render_diff_header(struct add_p_state *s,
}
}
/* Coalesce hunks again that were split */
static int merge_hunks(struct add_p_state *s, struct file_diff *file_diff,
size_t *hunk_index, struct hunk *merged)
{
size_t i = *hunk_index;
struct hunk *hunk = file_diff->hunk + i;
/* `header` corresponds to the merged hunk */
struct hunk_header *header = &merged->header, *next;
if (hunk->use != USE_HUNK)
return 0;
*merged = *hunk;
/* We simply skip the colored part (if any) when merging hunks */
merged->colored_start = merged->colored_end = 0;
for (; i + 1 < file_diff->hunk_nr; i++) {
hunk++;
next = &hunk->header;
/*
* Stop merging hunks when:
*
* - the hunk is not selected for use, or
* - the hunk does not overlap with the already-merged hunk(s)
*/
if (hunk->use != USE_HUNK ||
header->new_offset >= next->new_offset ||
header->new_offset + header->new_count < next->new_offset ||
merged->start >= hunk->start ||
merged->end < hunk->start)
break;
merged->end = hunk->end;
merged->colored_end = hunk->colored_end;
header->old_count = next->old_offset + next->old_count
- header->old_offset;
header->new_count = next->new_offset + next->new_count
- header->new_offset;
}
if (i == *hunk_index)
return 0;
*hunk_index = i;
return 1;
}
static void reassemble_patch(struct add_p_state *s,
struct file_diff *file_diff, struct strbuf *out)
{
@ -443,12 +492,19 @@ static void reassemble_patch(struct add_p_state *s,
render_diff_header(s, file_diff, 0, out);
for (i = file_diff->mode_change; i < file_diff->hunk_nr; i++) {
struct hunk merged = { 0 };
hunk = file_diff->hunk + i;
if (hunk->use != USE_HUNK)
delta += hunk->header.old_count
- hunk->header.new_count;
else
else {
/* merge overlapping hunks into a temporary hunk */
if (merge_hunks(s, file_diff, &i, &merged))
hunk = &merged;
render_hunk(s, hunk, delta, 0, out);
}
}
}