Merge branch 'gh/maint-stash-show-error-message'

diff --git a/builtin/revert.c b/builtin/revert.c
index eff52687a87b45b766e064eede7c2c35b6d133d2..9a3c14c329713f16d14147b81a4b8031028a4f82 100644 (file)
--- a/builtin/revert.c
+++ b/builtin/revert.c
@@ -13,6 +13,7 @@
 #include "revision.h"
 #include "rerere.h"
 #include "merge-recursive.h"
+#include "refs.h"
 
 /*
  * This implements the builtins revert and cherry-pick.
@@ -35,7 +36,7 @@ static const char * const cherry_pick_usage[] = {
        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 struct commit *commit;
 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_RERERE_AUTOUPDATE(&allow_rerere_auto),
                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)
                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)
 {
        unsigned char head[20];
@@ -251,7 +274,7 @@ static int revert_or_cherry_pick(int argc, const char **argv)
        int i, index_fd, clean;
        char *oneline, *reencoded_message = NULL;
        const char *message, *encoding;
-       char *defmsg = git_pathdup("MERGE_MSG");
+       char *defmsg = NULL;
        struct merge_options o;
        struct tree *result, *next_tree, *base_tree, *head_tree;
        static struct lock_file index_lock;
@@ -265,6 +288,17 @@ static int revert_or_cherry_pick(int argc, const char **argv)
        if (action == REVERT && !no_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)
                die("git %s: failed to read the index", me);
        if (no_commit) {
@@ -284,8 +318,6 @@ static int revert_or_cherry_pick(int argc, const char **argv)
        }
        discard_cache();
 
-       index_fd = hold_locked_index(&index_lock, 1);
-
        if (!commit->parents) {
                if (action == REVERT)
                        die ("Cannot revert a root commit");
@@ -314,6 +346,9 @@ static int revert_or_cherry_pick(int argc, const char **argv)
        else
                parent = commit->parents->item;
 
+       if (allow_ff && !hashcmp(parent->object.sha1, head))
+               return fast_forward_to(commit->object.sha1, head);
+
        if (!(message = commit->buffer))
                die ("Cannot get commit message for %s",
                                sha1_to_hex(commit->object.sha1));
@@ -329,6 +364,7 @@ static int revert_or_cherry_pick(int argc, const char **argv)
         * reverse of it if we are revert.
         */
 
+       defmsg = git_pathdup("MERGE_MSG");
        msg_fd = hold_lock_file_for_update(&msg_file, defmsg,
                                           LOCK_DIE_ON_ERROR);
 
@@ -343,6 +379,8 @@ static int revert_or_cherry_pick(int argc, const char **argv)
 
        oneline = get_oneline(message);
 
+       index_fd = hold_locked_index(&index_lock, 1);
+
        if (action == REVERT) {
                char *oneline_body = strchr(oneline, ' ');