From 700fd28e4f3ecd6e7b5f8f2098e62ffef9ab958b Mon Sep 17 00:00:00 2001
From: Max Kirillov <max@max630.net>
Date: Fri, 30 Oct 2015 07:01:53 +0200
Subject: [PATCH] blame: allow blame --reverse --first-parent when it makes
sense
Allow combining --reverse and --first-parent if initial commit of
specified range is at the first-parent chain starting from the final
commit. Disable the prepare_revision_walk()'s builtin children
collection, instead picking only the ones which are along the first
parent chain.
Signed-off-by: Max Kirillov <max@max630.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
builtin/blame.c | 32 +++++++++++++++++++++++++++++--
t/t8009-blame-vs-topicbranches.sh | 2 +-
2 files changed, 31 insertions(+), 3 deletions(-)
diff --git a/builtin/blame.c b/builtin/blame.c
index 7b075583cf5..861a5372b91 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -2502,6 +2502,7 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
long dashdash_pos, lno;
char *final_commit_name = NULL;
enum object_type type;
+ struct commit *final_commit = NULL;
static struct string_list range_list;
static int output_option = 0, opt = 0;
@@ -2689,11 +2690,11 @@ parse_done:
}
else if (contents_from)
die("--contents and --children do not blend well.");
- else if (revs.first_parent_only)
- die("combining --first-parent and --reverse is not supported");
else {
final_commit_name = prepare_initial(&sb);
sb.commits.compare = compare_commits_by_reverse_commit_date;
+ if (revs.first_parent_only)
+ revs.children.name = NULL;
}
if (!sb.final) {
@@ -2710,6 +2711,14 @@ parse_done:
else if (contents_from)
die("Cannot use --contents with final commit object name");
+ if (reverse && revs.first_parent_only) {
+ struct object_array_entry *entry = find_single_final(sb.revs);
+ if (!entry)
+ die("--reverse and --first-parent together require specified latest commit");
+ else
+ final_commit = (struct commit*) entry->item;
+ }
+
/*
* If we have bottom, this will mark the ancestors of the
* bottom commits we would reach while traversing as
@@ -2718,6 +2727,25 @@ parse_done:
if (prepare_revision_walk(&revs))
die(_("revision walk setup failed"));
+ if (reverse && revs.first_parent_only) {
+ struct commit *c = final_commit;
+
+ sb.revs->children.name = "children";
+ while (c->parents &&
+ hashcmp(c->object.sha1, sb.final->object.sha1)) {
+ struct commit_list *l = xcalloc(1, sizeof(*l));
+
+ l->item = c;
+ if (add_decoration(&sb.revs->children,
+ &c->parents->item->object, l))
+ die("BUG: not unique item in first-parent chain");
+ c = c->parents->item;
+ }
+
+ if (hashcmp(c->object.sha1, sb.final->object.sha1))
+ die("--reverse --first-parent together require range along first-parent chain");
+ }
+
if (is_null_sha1(sb.final->object.sha1)) {
o = sb.final->util;
sb.final_buf = xmemdupz(o->file.ptr, o->file.size);
diff --git a/t/t8009-blame-vs-topicbranches.sh b/t/t8009-blame-vs-topicbranches.sh
index 175ad376bdc..72596e38b25 100755
--- a/t/t8009-blame-vs-topicbranches.sh
+++ b/t/t8009-blame-vs-topicbranches.sh
@@ -26,7 +26,7 @@ test_expect_success setup '
test_merge A3 C1
'
-test_expect_failure 'blame --reverse --first-parent finds A1' '
+test_expect_success 'blame --reverse --first-parent finds A1' '
git blame --porcelain --reverse --first-parent A0..A3 -- file.t >actual_full &&
head -n 1 <actual_full | sed -e "s/ .*//" >actual &&
git rev-parse A1 >expect &&