Merge branch 'tt/help'

[git.git] / builtin-revert.c

diff --git a/builtin-revert.c b/builtin-revert.c
index a9347cf9c57b2e4d15d37da609a2851e5b1cfc8e..a0586f9753189d13d5af1c790ea875a5f383f34f 100644 (file)
--- a/builtin-revert.c
+++ b/builtin-revert.c
@@ -30,7 +30,7 @@ static const char * const cherry_pick_usage[] = {
        NULL
 };
 
-static int edit, no_replay, no_commit, needed_deref;
+static int edit, no_replay, no_commit, mainline;
 static enum { REVERT, CHERRY_PICK } action;
 static struct commit *commit;
 
@@ -50,12 +50,14 @@ static void parse_args(int argc, const char **argv)
                OPT_BOOLEAN('e', "edit", &edit, "edit the commit message"),
                OPT_BOOLEAN('x', NULL, &no_replay, "append commit name when cherry-picking"),
                OPT_BOOLEAN('r', NULL, &noop, "no-op (backward compatibility)"),
+               OPT_INTEGER('m', "mainline", &mainline, "parent number"),
                OPT_END(),
        };
 
        if (parse_options(argc, argv, options, usage_str, 0) != 1)
                usage_with_options(usage_str, options);
        arg = argv[0];
+
        if (get_sha1(arg, sha1))
                die ("Cannot find '%s'", arg);
        commit = (struct commit *)parse_object(sha1);
@@ -64,7 +66,6 @@ static void parse_args(int argc, const char **argv)
        if (commit->object.type == OBJ_TAG) {
                commit = (struct commit *)
                        deref_tag((struct object *)commit, arg, strlen(arg));
-               needed_deref = 1;
        }
        if (commit->object.type != OBJ_COMMIT)
                die ("'%s' does not point to a commit", arg);
@@ -226,7 +227,7 @@ static int merge_recursive(const char *base_sha1,
 static int revert_or_cherry_pick(int argc, const char **argv)
 {
        unsigned char head[20];
-       struct commit *base, *next;
+       struct commit *base, *next, *parent;
        int i;
        char *oneline, *reencoded_message = NULL;
        const char *message, *encoding;
@@ -244,7 +245,9 @@ static int revert_or_cherry_pick(int argc, const char **argv)
        if (no_commit) {
                /*
                 * We do not intend to commit immediately.  We just want to
-                * merge the differences in.
+                * merge the differences in, so let's compute the tree
+                * that represents the "current" state for merge-recursive
+                * to work on.
                 */
                if (write_tree(head, 0, NULL))
                        die ("Your index file is unmerged.");
@@ -254,15 +257,36 @@ static int revert_or_cherry_pick(int argc, const char **argv)
                if (get_sha1("HEAD", head))
                        die ("You do not have a valid HEAD");
                wt_status_prepare(&s);
-               if (s.commitable || s.workdir_dirty)
+               if (s.commitable)
                        die ("Dirty index: cannot %s", me);
                discard_cache();
        }
 
        if (!commit->parents)
                die ("Cannot %s a root commit", me);
-       if (commit->parents->next)
-               die ("Cannot %s a multi-parent commit.", me);
+       if (commit->parents->next) {
+               /* Reverting or cherry-picking a merge commit */
+               int cnt;
+               struct commit_list *p;
+
+               if (!mainline)
+                       die("Commit %s is a merge but no -m option was given.",
+                           sha1_to_hex(commit->object.sha1));
+
+               for (cnt = 1, p = commit->parents;
+                    cnt != mainline && p;
+                    cnt++)
+                       p = p->next;
+               if (cnt != mainline || !p)
+                       die("Commit %s does not have parent %d",
+                           sha1_to_hex(commit->object.sha1), mainline);
+               parent = p->item;
+       } else if (0 < mainline)
+               die("Mainline was specified but commit %s is not a merge.",
+                   sha1_to_hex(commit->object.sha1));
+       else
+               parent = commit->parents->item;
+
        if (!(message = commit->buffer))
                die ("Cannot get commit message for %s",
                                sha1_to_hex(commit->object.sha1));
@@ -291,14 +315,14 @@ static int revert_or_cherry_pick(int argc, const char **argv)
                char *oneline_body = strchr(oneline, ' ');
 
                base = commit;
-               next = commit->parents->item;
+               next = parent;
                add_to_msg("Revert \"");
                add_to_msg(oneline_body + 1);
                add_to_msg("\"\n\nThis reverts commit ");
                add_to_msg(sha1_to_hex(commit->object.sha1));
                add_to_msg(".\n");
        } else {
-               base = commit->parents->item;
+               base = parent;
                next = commit;
                set_author_ident_env(message);
                add_message_to_msg(message);
@@ -308,17 +332,6 @@ static int revert_or_cherry_pick(int argc, const char **argv)
                        add_to_msg(")\n");
                }
        }
-       if (needed_deref) {
-               add_to_msg("(original 'git ");
-               add_to_msg(me);
-               add_to_msg("' arguments: ");
-               for (i = 0; i < argc; i++) {
-                       if (i)
-                               add_to_msg(" ");
-                       add_to_msg(argv[i]);
-               }
-               add_to_msg(")\n");
-       }
 
        if (merge_recursive(sha1_to_hex(base->object.sha1),
                                sha1_to_hex(head), "HEAD",