revert: add "--strategy" option to choose merge strategy

This patch makes it possible to use a different merge strategy when
cherry-picking. This is usefull mainly for debugging purposes as it
allows to see if some failures are caused by the merge strategy used or
not.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/revert.c b/builtin/revert.c
index f4ad0fc971bdbd5d372b74dbe4afbff07ddcc6f8..b70f4b0af364caa597ab24630fc43fb41438ca2c 100644 (file)
--- a/builtin/revert.c
+++ b/builtin/revert.c
@@ -42,6 +42,7 @@ static const char *commit_name;
 static int allow_rerere_auto;
 
 static const char *me;
+static const char *strategy;
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
@@ -61,6 +62,7 @@ static void parse_args(int argc, const char **argv)
                OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
                OPT_INTEGER('m', "mainline", &mainline, "parent number"),
                OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
+               OPT_STRING(0, "strategy", &strategy, "strategy", "merge strategy"),
                OPT_END(),
        };
 
@@ -444,8 +446,27 @@ static int revert_or_cherry_pick(int argc, const char **argv)
                }
        }
 
-       do_recursive_merge(base, next, base_label, next_label,
-                          head, &msgbuf, defmsg);
+       if (!strategy || !strcmp(strategy, "recursive") || action == REVERT)
+               do_recursive_merge(base, next, base_label, next_label,
+                                  head, &msgbuf, defmsg);
+       else {
+               int res;
+               struct commit_list *common = NULL;
+               struct commit_list *remotes = NULL;
+               write_message(&msgbuf, defmsg);
+               commit_list_insert(base, &common);
+               commit_list_insert(next, &remotes);
+               res = try_merge_command(strategy, common,
+                                       sha1_to_hex(head), remotes);
+               free_commit_list(common);
+               free_commit_list(remotes);
+               if (res) {
+                       fprintf(stderr, "Automatic %s with strategy %s failed.%s\n",
+                               me, strategy, help_msg(commit_name));
+                       rerere(allow_rerere_auto);
+                       exit(1);
+               }
+       }
 
        /*
         *