revert: add --ff option to allow fast forward when cherry-picking

As "git merge" fast forwards if possible, it seems sensible to
have such a feature for "git cherry-pick" too, especially as it
could be used in git-rebase--interactive.sh.

Maybe this option could be made the default in the long run, with
another --no-ff option to disable this default behavior, but that
could make some scripts backward incompatible and/or that would
require testing if some GIT_AUTHOR_* environment variables are
set. So we don't do that for now.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Junio C Hamano 2010-03-06 21:34:42 +01:00
parent cac42b266a
commit c62f6ec341

View file

@ -13,6 +13,7 @@
#include "revision.h" #include "revision.h"
#include "rerere.h" #include "rerere.h"
#include "merge-recursive.h" #include "merge-recursive.h"
#include "refs.h"
/* /*
* This implements the builtins revert and cherry-pick. * This implements the builtins revert and cherry-pick.
@ -35,7 +36,7 @@ static const char * const cherry_pick_usage[] = {
NULL NULL
}; };
static int edit, no_replay, no_commit, mainline, signoff; static int edit, no_replay, no_commit, mainline, signoff, allow_ff;
static enum { REVERT, CHERRY_PICK } action; static enum { REVERT, CHERRY_PICK } action;
static struct commit *commit; static struct commit *commit;
static const char *commit_name; static const char *commit_name;
@ -60,8 +61,19 @@ static void parse_args(int argc, const char **argv)
OPT_INTEGER('m', "mainline", &mainline, "parent number"), OPT_INTEGER('m', "mainline", &mainline, "parent number"),
OPT_RERERE_AUTOUPDATE(&allow_rerere_auto), OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
OPT_END(), OPT_END(),
OPT_END(),
OPT_END(),
}; };
if (action == CHERRY_PICK) {
struct option cp_extra[] = {
OPT_BOOLEAN(0, "ff", &allow_ff, "allow fast-forward"),
OPT_END(),
};
if (parse_options_concat(options, ARRAY_SIZE(options), cp_extra))
die("program error");
}
if (parse_options(argc, argv, NULL, options, usage_str, 0) != 1) if (parse_options(argc, argv, NULL, options, usage_str, 0) != 1)
usage_with_options(usage_str, options); usage_with_options(usage_str, options);
@ -244,6 +256,17 @@ static NORETURN void die_dirty_index(const char *me)
} }
} }
static int fast_forward_to(const unsigned char *to, const unsigned char *from)
{
struct ref_lock *ref_lock;
read_cache();
if (checkout_fast_forward(from, to))
exit(1); /* the callee should have complained already */
ref_lock = lock_any_ref_for_update("HEAD", from, 0);
return write_ref_sha1(ref_lock, to, "cherry-pick");
}
static int revert_or_cherry_pick(int argc, const char **argv) static int revert_or_cherry_pick(int argc, const char **argv)
{ {
unsigned char head[20]; unsigned char head[20];
@ -265,6 +288,17 @@ static int revert_or_cherry_pick(int argc, const char **argv)
if (action == REVERT && !no_replay) if (action == REVERT && !no_replay)
die("revert is incompatible with replay"); die("revert is incompatible with replay");
if (allow_ff) {
if (signoff)
die("cherry-pick --ff cannot be used with --signoff");
if (no_commit)
die("cherry-pick --ff cannot be used with --no-commit");
if (no_replay)
die("cherry-pick --ff cannot be used with -x");
if (edit)
die("cherry-pick --ff cannot be used with --edit");
}
if (read_cache() < 0) if (read_cache() < 0)
die("git %s: failed to read the index", me); die("git %s: failed to read the index", me);
if (no_commit) { if (no_commit) {
@ -284,8 +318,6 @@ static int revert_or_cherry_pick(int argc, const char **argv)
} }
discard_cache(); discard_cache();
index_fd = hold_locked_index(&index_lock, 1);
if (!commit->parents) { if (!commit->parents) {
if (action == REVERT) if (action == REVERT)
die ("Cannot revert a root commit"); die ("Cannot revert a root commit");
@ -314,6 +346,9 @@ static int revert_or_cherry_pick(int argc, const char **argv)
else else
parent = commit->parents->item; parent = commit->parents->item;
if (allow_ff && !hashcmp(parent->object.sha1, head))
return fast_forward_to(commit->object.sha1, head);
if (!(message = commit->buffer)) if (!(message = commit->buffer))
die ("Cannot get commit message for %s", die ("Cannot get commit message for %s",
sha1_to_hex(commit->object.sha1)); sha1_to_hex(commit->object.sha1));
@ -343,6 +378,8 @@ static int revert_or_cherry_pick(int argc, const char **argv)
oneline = get_oneline(message); oneline = get_oneline(message);
index_fd = hold_locked_index(&index_lock, 1);
if (action == REVERT) { if (action == REVERT) {
char *oneline_body = strchr(oneline, ' '); char *oneline_body = strchr(oneline, ' ');