1 files changed, 254 insertions, 168 deletions

diff --git a/sequencer.c b/sequencer.c
index 9d5964fd81..6fd2674632 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -40,7 +40,7 @@ static const char cherry_picked_prefix[] = "(cherry picked from commit ";
 
 GIT_PATH_FUNC(git_path_commit_editmsg, "COMMIT_EDITMSG")
 
-GIT_PATH_FUNC(git_path_seq_dir, "sequencer")
+static GIT_PATH_FUNC(git_path_seq_dir, "sequencer")
 
 static GIT_PATH_FUNC(git_path_todo_file, "sequencer/todo")
 static GIT_PATH_FUNC(git_path_opts_file, "sequencer/opts")
@@ -57,6 +57,8 @@ static GIT_PATH_FUNC(rebase_path, "rebase-merge")
 GIT_PATH_FUNC(rebase_path_todo, "rebase-merge/git-rebase-todo")
 GIT_PATH_FUNC(rebase_path_todo_backup, "rebase-merge/git-rebase-todo.backup")
 
+GIT_PATH_FUNC(rebase_path_dropped, "rebase-merge/dropped")
+
 /*
  * The rebase command lines that have already been processed. A line
  * is moved here when it is first handled, before any associated user
@@ -131,7 +133,7 @@ static GIT_PATH_FUNC(rebase_path_rewritten_pending,
 	"rebase-merge/rewritten-pending")
 
 /*
- * The path of the file containig the OID of the "squash onto" commit, i.e.
+ * The path of the file containing the OID of the "squash onto" commit, i.e.
  * the dummy commit used for `reset [new root]`.
  */
 static GIT_PATH_FUNC(rebase_path_squash_onto, "rebase-merge/squash-onto")
@@ -158,6 +160,8 @@ static GIT_PATH_FUNC(rebase_path_strategy, "rebase-merge/strategy")
 static GIT_PATH_FUNC(rebase_path_strategy_opts, "rebase-merge/strategy_opts")
 static GIT_PATH_FUNC(rebase_path_allow_rerere_autoupdate, "rebase-merge/allow_rerere_autoupdate")
 static GIT_PATH_FUNC(rebase_path_reschedule_failed_exec, "rebase-merge/reschedule-failed-exec")
+static GIT_PATH_FUNC(rebase_path_drop_redundant_commits, "rebase-merge/drop_redundant_commits")
+static GIT_PATH_FUNC(rebase_path_keep_redundant_commits, "rebase-merge/keep_redundant_commits")
 
 static int git_sequencer_config(const char *k, const char *v, void *cb)
 {
@@ -288,7 +292,7 @@ int sequencer_remove_state(struct replay_opts *opts)
 			char *eol = strchr(p, '\n');
 			if (eol)
 				*eol = '\0';
-			if (delete_ref("(rebase -i) cleanup", p, NULL, 0) < 0) {
+			if (delete_ref("(rebase) cleanup", p, NULL, 0) < 0) {
 				warning(_("could not delete '%s'"), p);
 				ret = -1;
 			}
@@ -322,7 +326,7 @@ static const char *action_name(const struct replay_opts *opts)
 	case REPLAY_PICK:
 		return N_("cherry-pick");
 	case REPLAY_INTERACTIVE_REBASE:
-		return N_("rebase -i");
+		return N_("rebase");
 	}
 	die(_("unknown action: %d"), opts->action);
 }
@@ -588,7 +592,7 @@ static int do_recursive_merge(struct repository *r,
 	struct merge_options o;
 	struct tree *next_tree, *base_tree, *head_tree;
 	int clean;
-	char **xopt;
+	int i;
 	struct lock_file index_lock = LOCK_INIT;
 
 	if (repo_hold_locked_index(r, &index_lock, LOCK_REPORT_ON_ERROR) < 0)
@@ -608,8 +612,8 @@ static int do_recursive_merge(struct repository *r,
 	next_tree = next ? get_commit_tree(next) : empty_tree(r);
 	base_tree = base ? get_commit_tree(base) : empty_tree(r);
 
-	for (xopt = opts->xopts; xopt != opts->xopts + opts->xopts_nr; xopt++)
-		parse_merge_opt(&o, *xopt);
+	for (i = 0; i < opts->xopts_nr; i++)
+		parse_merge_opt(&o, opts->xopts[i]);
 
 	clean = merge_trees(&o,
 			    head_tree,
@@ -626,7 +630,7 @@ static int do_recursive_merge(struct repository *r,
 			       COMMIT_LOCK | SKIP_IF_UNCHANGED))
 		/*
 		 * TRANSLATORS: %s will be "revert", "cherry-pick" or
-		 * "rebase -i".
+		 * "rebase".
 		 */
 		return error(_("%s: Unable to write new index file"),
 			_(action_name(opts)));
@@ -1126,25 +1130,22 @@ static int run_prepare_commit_msg_hook(struct repository *r,
 				       struct strbuf *msg,
 				       const char *commit)
 {
-	struct argv_array hook_env = ARGV_ARRAY_INIT;
-	int ret;
-	const char *name;
+	int ret = 0;
+	const char *name, *arg1 = NULL, *arg2 = NULL;
 
 	name = git_path_commit_editmsg();
 	if (write_message(msg->buf, msg->len, name, 0))
 		return -1;
 
-	argv_array_pushf(&hook_env, "GIT_INDEX_FILE=%s", r->index_file);
-	argv_array_push(&hook_env, "GIT_EDITOR=:");
-	if (commit)
-		ret = run_hook_le(hook_env.argv, "prepare-commit-msg", name,
-				  "commit", commit, NULL);
-	else
-		ret = run_hook_le(hook_env.argv, "prepare-commit-msg", name,
-				  "message", NULL);
-	if (ret)
+	if (commit) {
+		arg1 = "commit";
+		arg2 = commit;
+	} else {
+		arg1 = "message";
+	}
+	if (run_commit_hook(0, r->index_file, "prepare-commit-msg", name,
+			    arg1, arg2, NULL))
 		ret = error(_("'prepare-commit-msg' hook failed"));
-	argv_array_clear(&hook_env);
 
 	return ret;
 }
@@ -1322,7 +1323,7 @@ static int try_to_commit(struct repository *r,
 		return -1;
 
 	if (flags & AMEND_MSG) {
-		const char *exclude_gpgsig[] = { "gpgsig", NULL };
+		const char *exclude_gpgsig[] = { "gpgsig", "gpgsig-sha256", NULL };
 		const char *out_enc = get_commit_output_encoding();
 		const char *message = logmsg_reencode(current_head, NULL,
 						      out_enc);
@@ -1353,11 +1354,27 @@ static int try_to_commit(struct repository *r,
 		goto out;
 	}
 
-	if (!(flags & ALLOW_EMPTY) && oideq(current_head ?
-					    get_commit_tree_oid(current_head) :
-					    the_hash_algo->empty_tree, &tree)) {
-		res = 1; /* run 'git commit' to display error message */
-		goto out;
+	if (!(flags & ALLOW_EMPTY)) {
+		struct commit *first_parent = current_head;
+
+		if (flags & AMEND_MSG) {
+			if (current_head->parents) {
+				first_parent = current_head->parents->item;
+				if (repo_parse_commit(r, first_parent)) {
+					res = error(_("could not parse HEAD commit"));
+					goto out;
+				}
+			} else {
+				first_parent = NULL;
+			}
+		}
+		if (oideq(first_parent
+			  ? get_commit_tree_oid(first_parent)
+			  : the_hash_algo->empty_tree,
+			  &tree)) {
+			res = 1; /* run 'git commit' to display error message */
+			goto out;
+		}
 	}
 
 	if (find_hook("prepare-commit-msg")) {
@@ -1403,6 +1420,7 @@ static int try_to_commit(struct repository *r,
 		goto out;
 	}
 
+	run_commit_hook(0, r->index_file, "post-commit", NULL);
 	if (flags & AMEND_MSG)
 		commit_post_rewrite(r, current_head, oid);
 
@@ -1415,9 +1433,19 @@ out:
 	return res;
 }
 
+static int write_rebase_head(struct object_id *oid)
+{
+	if (update_ref("rebase", "REBASE_HEAD", oid,
+		       NULL, REF_NO_DEREF, UPDATE_REFS_MSG_ON_ERR))
+		return error(_("could not update %s"), "REBASE_HEAD");
+
+	return 0;
+}
+
 static int do_commit(struct repository *r,
 		     const char *msg_file, const char *author,
-		     struct replay_opts *opts, unsigned int flags)
+		     struct replay_opts *opts, unsigned int flags,
+		     struct object_id *oid)
 {
 	int res = 1;
 
@@ -1442,8 +1470,12 @@ static int do_commit(struct repository *r,
 			return res;
 		}
 	}
-	if (res == 1)
+	if (res == 1) {
+		if (is_rebase_i(opts) && oid)
+			if (write_rebase_head(oid))
+			    return -1;
 		return run_git_commit(r, msg_file, opts, flags);
+	}
 
 	return res;
 }
@@ -1469,23 +1501,30 @@ static int is_original_commit_empty(struct commit *commit)
 }
 
 /*
- * Do we run "git commit" with "--allow-empty"?
+ * Should empty commits be allowed?  Return status:
+ *    <0: Error in is_index_unchanged(r) or is_original_commit_empty(commit)
+ *     0: Halt on empty commit
+ *     1: Allow empty commit
+ *     2: Drop empty commit
  */
 static int allow_empty(struct repository *r,
 		       struct replay_opts *opts,
 		       struct commit *commit)
 {
-	int index_unchanged, empty_commit;
+	int index_unchanged, originally_empty;
 
 	/*
-	 * Three cases:
+	 * Four cases:
 	 *
 	 * (1) we do not allow empty at all and error out.
 	 *
-	 * (2) we allow ones that were initially empty, but
-	 * forbid the ones that become empty;
+	 * (2) we allow ones that were initially empty, and
+	 *     just drop the ones that become empty
+	 *
+	 * (3) we allow ones that were initially empty, but
+	 *     halt for the ones that become empty;
 	 *
-	 * (3) we allow both.
+	 * (4) we allow both.
 	 */
 	if (!opts->allow_empty)
 		return 0; /* let "git commit" barf as necessary */
@@ -1499,13 +1538,15 @@ static int allow_empty(struct repository *r,
 	if (opts->keep_redundant_commits)
 		return 1;
 
-	empty_commit = is_original_commit_empty(commit);
-	if (empty_commit < 0)
-		return empty_commit;
-	if (!empty_commit)
-		return 0;
-	else
+	originally_empty = is_original_commit_empty(commit);
+	if (originally_empty < 0)
+		return originally_empty;
+	if (originally_empty)
 		return 1;
+	else if (opts->drop_redundant_commits)
+		return 2;
+	else
+		return 0;
 }
 
 static struct {
@@ -1576,6 +1617,7 @@ static int update_squash_messages(struct repository *r,
 	struct strbuf buf = STRBUF_INIT;
 	int res;
 	const char *message, *body;
+	const char *encoding = get_commit_output_encoding();
 
 	if (opts->current_fixup_count > 0) {
 		struct strbuf header = STRBUF_INIT;
@@ -1602,7 +1644,7 @@ static int update_squash_messages(struct repository *r,
 			return error(_("need a HEAD to fixup"));
 		if (!(head_commit = lookup_commit_reference(r, &head)))
 			return error(_("could not read HEAD"));
-		if (!(head_message = get_commit_buffer(head_commit, NULL)))
+		if (!(head_message = logmsg_reencode(head_commit, NULL, encoding)))
 			return error(_("could not read HEAD's commit message"));
 
 		find_commit_subject(head_message, &body);
@@ -1623,7 +1665,7 @@ static int update_squash_messages(struct repository *r,
 		unuse_commit_buffer(head_commit, head_message);
 	}
 
-	if (!(message = get_commit_buffer(commit, NULL)))
+	if (!(message = logmsg_reencode(commit, NULL, encoding)))
 		return error(_("could not read commit message of %s"),
 			     oid_to_hex(&commit->object.oid));
 	find_commit_subject(message, &body);
@@ -1715,7 +1757,7 @@ static int do_pick_commit(struct repository *r,
 	char *author = NULL;
 	struct commit_message msg = { NULL, NULL, NULL, NULL };
 	struct strbuf msgbuf = STRBUF_INIT;
-	int res, unborn = 0, reword = 0, allow;
+	int res, unborn = 0, reword = 0, allow, drop_commit;
 
 	if (opts->no_commit) {
 		/*
@@ -1901,7 +1943,9 @@ static int do_pick_commit(struct repository *r,
 	 * However, if the merge did not even start, then we don't want to
 	 * write it at all.
 	 */
-	if (command == TODO_PICK && !opts->no_commit && (res == 0 || res == 1) &&
+	if ((command == TODO_PICK || command == TODO_REWORD ||
+	     command == TODO_EDIT) && !opts->no_commit &&
+	    (res == 0 || res == 1) &&
 	    update_ref(NULL, "CHERRY_PICK_HEAD", &commit->object.oid, NULL,
 		       REF_NO_DEREF, UPDATE_REFS_MSG_ON_ERR))
 		res = -1;
@@ -1920,15 +1964,25 @@ static int do_pick_commit(struct repository *r,
 		goto leave;
 	}
 
+	drop_commit = 0;
 	allow = allow_empty(r, opts, commit);
 	if (allow < 0) {
 		res = allow;
 		goto leave;
-	} else if (allow)
+	} else if (allow == 1) {
 		flags |= ALLOW_EMPTY;
-	if (!opts->no_commit) {
+	} else if (allow == 2) {
+		drop_commit = 1;
+		unlink(git_path_cherry_pick_head(r));
+		unlink(git_path_merge_msg(r));
+		fprintf(stderr,
+			_("dropping %s %s -- patch contents already upstream\n"),
+			oid_to_hex(&commit->object.oid), msg.subject);
+	} /* else allow == 0 and there's nothing special to do */
+	if (!opts->no_commit && !drop_commit) {
 		if (author || command == TODO_REVERT || (flags & AMEND_MSG))
-			res = do_commit(r, msg_file, author, opts, flags);
+			res = do_commit(r, msg_file, author, opts, flags,
+					commit? &commit->object.oid : NULL);
 		else
 			res = error(_("unable to parse commit author"));
 		*check_todo = !!(flags & EDIT_MSG);
@@ -2008,6 +2062,7 @@ void todo_list_release(struct todo_list *todo_list)
 static struct todo_item *append_new_todo(struct todo_list *todo_list)
 {
 	ALLOC_GROW(todo_list->items, todo_list->nr + 1, todo_list->alloc);
+	todo_list->total_nr++;
 	return todo_list->items + todo_list->nr++;
 }
 
@@ -2102,6 +2157,8 @@ static int parse_insn_line(struct repository *r, struct todo_item *item,
 	saved = *end_of_object_name;
 	*end_of_object_name = '\0';
 	status = get_oid(bol, &commit_oid);
+	if (status < 0)
+		error(_("could not parse '%s'"), bol); /* return later */
 	*end_of_object_name = saved;
 
 	bol = end_of_object_name + strspn(end_of_object_name, " \t");
@@ -2109,11 +2166,10 @@ static int parse_insn_line(struct repository *r, struct todo_item *item,
 	item->arg_len = (int)(eol - bol);
 
 	if (status < 0)
-		return error(_("could not parse '%.*s'"),
-			     (int)(end_of_object_name - bol), bol);
+		return status;
 
 	item->commit = lookup_commit_reference(r, &commit_oid);
-	return !item->commit;
+	return item->commit ? 0 : -1;
 }
 
 int sequencer_get_last_command(struct repository *r, enum replay_action *action)
@@ -2279,6 +2335,16 @@ void sequencer_post_commit_cleanup(struct repository *r, int verbose)
 	sequencer_remove_state(&opts);
 }
 
+static void todo_list_write_total_nr(struct todo_list *todo_list)
+{
+	FILE *f = fopen_or_warn(rebase_path_msgtotal(), "w");
+
+	if (f) {
+		fprintf(f, "%d\n", todo_list->total_nr);
+		fclose(f);
+	}
+}
+
 static int read_populate_todo(struct repository *r,
 			      struct todo_list *todo_list,
 			      struct replay_opts *opts)
@@ -2324,7 +2390,6 @@ static int read_populate_todo(struct repository *r,
 
 	if (is_rebase_i(opts)) {
 		struct todo_list done = TODO_LIST_INIT;
-		FILE *f = fopen_or_warn(rebase_path_msgtotal(), "w");
 
 		if (strbuf_read_file(&done.buf, rebase_path_done(), 0) > 0 &&
 		    !todo_list_parse_insn_buffer(r, done.buf.buf, &done))
@@ -2336,10 +2401,7 @@ static int read_populate_todo(struct repository *r,
 			+ count_commands(todo_list);
 		todo_list_release(&done);
 
-		if (f) {
-			fprintf(f, "%d\n", todo_list->total_nr);
-			fclose(f);
-		}
+		todo_list_write_total_nr(todo_list);
 	}
 
 	return 0;
@@ -2473,6 +2535,12 @@ static int read_populate_opts(struct replay_opts *opts)
 		if (file_exists(rebase_path_reschedule_failed_exec()))
 			opts->reschedule_failed_exec = 1;
 
+		if (file_exists(rebase_path_drop_redundant_commits()))
+			opts->drop_redundant_commits = 1;
+
+		if (file_exists(rebase_path_keep_redundant_commits()))
+			opts->keep_redundant_commits = 1;
+
 		read_strategy_opts(opts, &buf);
 		strbuf_release(&buf);
 
@@ -2524,8 +2592,6 @@ static void write_strategy_opts(struct replay_opts *opts)
 int write_basic_state(struct replay_opts *opts, const char *head_name,
 		      struct commit *onto, const char *orig_head)
 {
-	const char *quiet = getenv("GIT_QUIET");
-
 	if (head_name)
 		write_file(rebase_path_head_name(), "%s\n", head_name);
 	if (onto)
@@ -2534,8 +2600,8 @@ int write_basic_state(struct replay_opts *opts, const char *head_name,
 	if (orig_head)
 		write_file(rebase_path_orig_head(), "%s\n", orig_head);
 
-	if (quiet)
-		write_file(rebase_path_quiet(), "%s\n", quiet);
+	if (opts->quiet)
+		write_file(rebase_path_quiet(), "%s", "");
 	if (opts->verbose)
 		write_file(rebase_path_verbose(), "%s", "");
 	if (opts->strategy)
@@ -2552,6 +2618,10 @@ int write_basic_state(struct replay_opts *opts, const char *head_name,
 		write_file(rebase_path_gpg_sign_opt(), "-S%s\n", opts->gpg_sign);
 	if (opts->signoff)
 		write_file(rebase_path_signoff(), "--signoff\n");
+	if (opts->drop_redundant_commits)
+		write_file(rebase_path_drop_redundant_commits(), "%s", "");
+	if (opts->keep_redundant_commits)
+		write_file(rebase_path_keep_redundant_commits(), "%s", "");
 	if (opts->reschedule_failed_exec)
 		write_file(rebase_path_reschedule_failed_exec(), "%s", "");
 
@@ -2564,14 +2634,17 @@ static int walk_revs_populate_todo(struct todo_list *todo_list,
 	enum todo_command command = opts->action == REPLAY_PICK ?
 		TODO_PICK : TODO_REVERT;
 	const char *command_string = todo_command_info[command].str;
+	const char *encoding;
 	struct commit *commit;
 
 	if (prepare_revs(opts))
 		return -1;
 
+	encoding = get_log_output_encoding();
+
 	while ((commit = get_revision(opts->revs))) {
 		struct todo_item *item = append_new_todo(todo_list);
-		const char *commit_buffer = get_commit_buffer(commit, NULL);
+		const char *commit_buffer = logmsg_reencode(commit, NULL, encoding);
 		const char *subject;
 		int subject_len;
 
@@ -2944,9 +3017,7 @@ static int make_patch(struct repository *r,
 	p = short_commit_name(commit);
 	if (write_message(p, strlen(p), rebase_path_stopped_sha(), 1) < 0)
 		return -1;
-	if (update_ref("rebase", "REBASE_HEAD", &commit->object.oid,
-		       NULL, REF_NO_DEREF, UPDATE_REFS_MSG_ON_ERR))
-		res |= error(_("could not update %s"), "REBASE_HEAD");
+	res |= write_rebase_head(&commit->object.oid);
 
 	strbuf_addf(&buf, "%s/patch", get_dir(opts));
 	memset(&log_tree_opt, 0, sizeof(log_tree_opt));
@@ -2968,7 +3039,8 @@ static int make_patch(struct repository *r,
 
 	strbuf_addf(&buf, "%s/message", get_dir(opts));
 	if (!file_exists(buf.buf)) {
-		const char *commit_buffer = get_commit_buffer(commit, NULL);
+		const char *encoding = get_commit_output_encoding();
+		const char *commit_buffer = logmsg_reencode(commit, NULL, encoding);
 		find_commit_subject(commit_buffer, &subject);
 		res |= write_message(subject, strlen(subject), buf.buf, 1);
 		unuse_commit_buffer(commit, commit_buffer);
@@ -3147,7 +3219,7 @@ static int do_label(struct repository *r, const char *name, int len)
 		return error(_("illegal label name: '%.*s'"), len, name);
 
 	strbuf_addf(&ref_name, "refs/rewritten/%.*s", len, name);
-	strbuf_addf(&msg, "rebase -i (label) '%.*s'", len, name);
+	strbuf_addf(&msg, "rebase (label) '%.*s'", len, name);
 
 	transaction = ref_store_transaction_begin(refs, &err);
 	if (!transaction) {
@@ -3233,6 +3305,7 @@ static int do_reset(struct repository *r,
 	unpack_tree_opts.fn = oneway_merge;
 	unpack_tree_opts.merge = 1;
 	unpack_tree_opts.update = 1;
+	init_checkout_metadata(&unpack_tree_opts.meta, name, &oid, NULL);
 
 	if (repo_read_index_unmerged(r)) {
 		rollback_lock_file(&lock);
@@ -3370,7 +3443,8 @@ static int do_merge(struct repository *r,
 	}
 
 	if (commit) {
-		const char *message = get_commit_buffer(commit, NULL);
+		const char *encoding = get_commit_output_encoding();
+		const char *message = logmsg_reencode(commit, NULL, encoding);
 		const char *body;
 		int len;
 
@@ -3688,20 +3762,6 @@ static int run_git_checkout(struct repository *r, struct replay_opts *opts,
 	return ret;
 }
 
-int prepare_branch_to_be_rebased(struct repository *r, struct replay_opts *opts,
-				 const char *commit)
-{
-	const char *action;
-
-	if (commit && *commit) {
-		action = reflog_message(opts, "start", "checkout %s", commit);
-		if (run_git_checkout(r, opts, commit, action))
-			return error(_("could not checkout %s"), commit);
-	}
-
-	return 0;
-}
-
 static int checkout_onto(struct repository *r, struct replay_opts *opts,
 			 const char *onto_name, const struct object_id *onto,
 			 const char *orig_head)
@@ -3910,7 +3970,7 @@ static int pick_commits(struct repository *r,
 							item->commit,
 							arg, item->arg_len,
 							opts, res, 0);
-		} else if (check_todo && !res) {
+		} else if (is_rebase_i(opts) && check_todo && !res) {
 			struct stat st;
 
 			if (stat(get_todo_path(opts), &st)) {
@@ -4151,9 +4211,10 @@ static int commit_staged_changes(struct repository *r,
 				 */
 				struct commit *commit;
 				const char *path = rebase_path_squash_msg();
+				const char *encoding = get_commit_output_encoding();
 
 				if (parse_head(r, &commit) ||
-				    !(p = get_commit_buffer(commit, NULL)) ||
+				    !(p = logmsg_reencode(commit, NULL, encoding)) ||
 				    write_message(p, strlen(p), path, 0)) {
 					unuse_commit_buffer(commit, p);
 					return error(_("could not write file: "
@@ -4210,8 +4271,18 @@ int sequencer_continue(struct repository *r, struct replay_opts *opts)
 	if (is_rebase_i(opts)) {
 		if ((res = read_populate_todo(r, &todo_list, opts)))
 			goto release_todo_list;
-		if (commit_staged_changes(r, opts, &todo_list))
-			return -1;
+
+		if (file_exists(rebase_path_dropped())) {
+			if ((res = todo_list_check_against_backup(r, &todo_list)))
+				goto release_todo_list;
+
+			unlink(rebase_path_dropped());
+		}
+
+		if (commit_staged_changes(r, opts, &todo_list)) {
+			res = -1;
+			goto release_todo_list;
+		}
 	} else if (!file_exists(get_todo_path(opts)))
 		return continue_single_pick(r);
 	else if ((res = read_populate_todo(r, &todo_list, opts)))
@@ -4425,7 +4496,6 @@ static const char *label_oid(struct object_id *oid, const char *label,
 	struct labels_entry *labels_entry;
 	struct string_entry *string_entry;
 	struct object_id dummy;
-	size_t len;
 	int i;
 
 	string_entry = oidmap_get(&state->commit2label, oid);
@@ -4445,10 +4515,10 @@ static const char *label_oid(struct object_id *oid, const char *label,
 	 * abbreviation for any uninteresting commit's names that does not
 	 * clash with any other label.
 	 */
+	strbuf_reset(&state->buf);
 	if (!label) {
 		char *p;
 
-		strbuf_reset(&state->buf);
 		strbuf_grow(&state->buf, GIT_MAX_HEXSZ);
 		label = p = state->buf.buf;
 
@@ -4471,32 +4541,55 @@ static const char *label_oid(struct object_id *oid, const char *label,
 				p[i] = save;
 			}
 		}
-	} else if (((len = strlen(label)) == the_hash_algo->hexsz &&
-		    !get_oid_hex(label, &dummy)) ||
-		   (len == 1 && *label == '#') ||
-		   hashmap_get_from_hash(&state->labels,
-					 strihash(label), label)) {
+	} else {
+		struct strbuf *buf = &state->buf;
+
 		/*
-		 * If the label already exists, or if the label is a valid full
-		 * OID, or the label is a '#' (which we use as a separator
-		 * between merge heads and oneline), we append a dash and a
-		 * number to make it unique.
+		 * Sanitize labels by replacing non-alpha-numeric characters
+		 * (including white-space ones) by dashes, as they might be
+		 * illegal in file names (and hence in ref names).
+		 *
+		 * Note that we retain non-ASCII UTF-8 characters (identified
+		 * via the most significant bit). They should be all acceptable
+		 * in file names. We do not validate the UTF-8 here, that's not
+		 * the job of this function.
 		 */
-		struct strbuf *buf = &state->buf;
+		for (; *label; label++)
+			if ((*label & 0x80) || isalnum(*label))
+				strbuf_addch(buf, *label);
+			/* avoid leading dash and double-dashes */
+			else if (buf->len && buf->buf[buf->len - 1] != '-')
+				strbuf_addch(buf, '-');
+		if (!buf->len) {
+			strbuf_addstr(buf, "rev-");
+			strbuf_add_unique_abbrev(buf, oid, default_abbrev);
+		}
+		label = buf->buf;
 
-		strbuf_reset(buf);
-		strbuf_add(buf, label, len);
+		if ((buf->len == the_hash_algo->hexsz &&
+		     !get_oid_hex(label, &dummy)) ||
+		    (buf->len == 1 && *label == '#') ||
+		    hashmap_get_from_hash(&state->labels,
+					  strihash(label), label)) {
+			/*
+			 * If the label already exists, or if the label is a
+			 * valid full OID, or the label is a '#' (which we use
+			 * as a separator between merge heads and oneline), we
+			 * append a dash and a number to make it unique.
+			 */
+			size_t len = buf->len;
 
-		for (i = 2; ; i++) {
-			strbuf_setlen(buf, len);
-			strbuf_addf(buf, "-%d", i);
-			if (!hashmap_get_from_hash(&state->labels,
-						   strihash(buf->buf),
-						   buf->buf))
-				break;
-		}
+			for (i = 2; ; i++) {
+				strbuf_setlen(buf, len);
+				strbuf_addf(buf, "-%d", i);
+				if (!hashmap_get_from_hash(&state->labels,
+							   strihash(buf->buf),
+							   buf->buf))
+					break;
+			}
 
-		label = buf->buf;
+			label = buf->buf;
+		}
 	}
 
 	FLEX_ALLOC_STR(labels_entry, label, label);
@@ -4514,7 +4607,6 @@ static int make_script_with_merges(struct pretty_print_context *pp,
 				   struct rev_info *revs, struct strbuf *out,
 				   unsigned flags)
 {
-	int keep_empty = flags & TODO_LIST_KEEP_EMPTY;
 	int rebase_cousins = flags & TODO_LIST_REBASE_COUSINS;
 	int root_with_onto = flags & TODO_LIST_ROOT_WITH_ONTO;
 	struct strbuf buf = STRBUF_INIT, oneline = STRBUF_INIT;
@@ -4540,10 +4632,15 @@ static int make_script_with_merges(struct pretty_print_context *pp,
 	strbuf_init(&state.buf, 32);
 
 	if (revs->cmdline.nr && (revs->cmdline.rev[0].flags & BOTTOM)) {
+		struct labels_entry *onto_label_entry;
 		struct object_id *oid = &revs->cmdline.rev[0].item->oid;
 		FLEX_ALLOC_STR(entry, string, "onto");
 		oidcpy(&entry->entry.oid, oid);
 		oidmap_put(&state.commit2label, entry);
+
+		FLEX_ALLOC_STR(onto_label_entry, label, "onto");
+		hashmap_entry_init(&onto_label_entry->entry, strihash("onto"));
+		hashmap_add(&state.labels, &onto_label_entry->entry);
 	}
 
 	/*
@@ -4572,8 +4669,6 @@ static int make_script_with_merges(struct pretty_print_context *pp,
 		if (!to_merge) {
 			/* non-merge commit: easy case */
 			strbuf_reset(&buf);
-			if (!keep_empty && is_empty)
-				strbuf_addf(&buf, "%c ", comment_line_char);
 			strbuf_addf(&buf, "%s %s %s", cmd_pick,
 				    oid_to_hex(&commit->object.oid),
 				    oneline.buf);
@@ -4598,10 +4693,6 @@ static int make_script_with_merges(struct pretty_print_context *pp,
 		else
 			strbuf_addbuf(&label, &oneline);
 
-		for (p1 = label.buf; *p1; p1++)
-			if (isspace(*p1))
-				*(char *)p1 = '-';
-
 		strbuf_reset(&buf);
 		strbuf_addf(&buf, "%s -C %s",
 			    cmd_merge, oid_to_hex(&commit->object.oid));
@@ -4644,7 +4735,7 @@ static int make_script_with_merges(struct pretty_print_context *pp,
 				label_oid(oid, "branch-point", &state);
 		}
 
-		/* Add HEAD as implict "tip of branch" */
+		/* Add HEAD as implicit "tip of branch" */
 		if (!iter->next)
 			tips_tail = &commit_list_insert(iter->item,
 							tips_tail)->next;
@@ -4744,7 +4835,6 @@ int sequencer_make_script(struct repository *r, struct strbuf *out, int argc,
 	struct pretty_print_context pp = {0};
 	struct rev_info revs;
 	struct commit *commit;
-	int keep_empty = flags & TODO_LIST_KEEP_EMPTY;
 	const char *insn = flags & TODO_LIST_ABBREVIATE_CMDS ? "p" : "pick";
 	int rebase_merges = flags & TODO_LIST_REBASE_MERGES;
 
@@ -4780,12 +4870,10 @@ int sequencer_make_script(struct repository *r, struct strbuf *out, int argc,
 		return make_script_with_merges(&pp, &revs, out, flags);
 
 	while ((commit = get_revision(&revs))) {
-		int is_empty  = is_original_commit_empty(commit);
+		int is_empty = is_original_commit_empty(commit);
 
 		if (!is_empty && (commit->object.flags & PATCHSAME))
 			continue;
-		if (!keep_empty && is_empty)
-			strbuf_addf(out, "%c ", comment_line_char);
 		strbuf_addf(out, "%s %s ", insn,
 			    oid_to_hex(&commit->object.oid));
 		pretty_print_commit(&pp, commit, out);
@@ -4826,7 +4914,7 @@ void todo_list_add_exec_commands(struct todo_list *todo_list,
 	 * are considered part of the pick, so we insert the commands *after*
 	 * those chains if there are any.
 	 *
-	 * As we insert the exec commands immediatly after rearranging
+	 * As we insert the exec commands immediately after rearranging
 	 * any fixups and before the user edits the list, a fixup chain
 	 * can never contain comments (any comments are empty picks that
 	 * have been commented out because the user did not specify
@@ -4922,7 +5010,7 @@ int todo_list_write_to_file(struct repository *r, struct todo_list *todo_list,
 
 	todo_list_to_strbuf(r, todo_list, &buf, num, flags);
 	if (flags & TODO_LIST_APPEND_TODO_HELP)
-		append_todo_help(flags & TODO_LIST_KEEP_EMPTY, count_commands(todo_list),
+		append_todo_help(count_commands(todo_list),
 				 shortrevisions, shortonto, &buf);
 
 	res = write_message(buf.buf, buf.len, file, 0);
@@ -4931,41 +5019,6 @@ int todo_list_write_to_file(struct repository *r, struct todo_list *todo_list,
 	return res;
 }
 
-static const char edit_todo_list_advice[] =
-N_("You can fix this with 'git rebase --edit-todo' "
-"and then run 'git rebase --continue'.\n"
-"Or you can abort the rebase with 'git rebase"
-" --abort'.\n");
-
-int check_todo_list_from_file(struct repository *r)
-{
-	struct todo_list old_todo = TODO_LIST_INIT, new_todo = TODO_LIST_INIT;
-	int res = 0;
-
-	if (strbuf_read_file_or_whine(&new_todo.buf, rebase_path_todo()) < 0) {
-		res = -1;
-		goto out;
-	}
-
-	if (strbuf_read_file_or_whine(&old_todo.buf, rebase_path_todo_backup()) < 0) {
-		res = -1;
-		goto out;
-	}
-
-	res = todo_list_parse_insn_buffer(r, old_todo.buf.buf, &old_todo);
-	if (!res)
-		res = todo_list_parse_insn_buffer(r, new_todo.buf.buf, &new_todo);
-	if (!res)
-		res = todo_list_check(&old_todo, &new_todo);
-	if (res)
-		fprintf(stderr, _(edit_todo_list_advice));
-out:
-	todo_list_release(&old_todo);
-	todo_list_release(&new_todo);
-
-	return res;
-}
-
 /* skip picking commits whose parents are unchanged */
 static int skip_unnecessary_picks(struct repository *r,
 				  struct todo_list *todo_list,
@@ -5005,6 +5058,7 @@ static int skip_unnecessary_picks(struct repository *r,
 		MOVE_ARRAY(todo_list->items, todo_list->items + i, todo_list->nr - i);
 		todo_list->nr -= i;
 		todo_list->current = 0;
+		todo_list->done_nr += i;
 
 		if (is_fixup(peek_command(todo_list, 0)))
 			record_in_rewritten(base_oid, peek_command(todo_list, 0));
@@ -5021,7 +5075,7 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
 {
 	const char *shortonto, *todo_file = rebase_path_todo();
 	struct todo_list new_todo = TODO_LIST_INIT;
-	struct strbuf *buf = &todo_list->buf;
+	struct strbuf *buf = &todo_list->buf, buf2 = STRBUF_INIT;
 	struct object_id oid = onto->object.oid;
 	int res;
 
@@ -5062,17 +5116,22 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
 		todo_list_release(&new_todo);
 
 		return error(_("nothing to do"));
-	}
-
-	if (todo_list_parse_insn_buffer(r, new_todo.buf.buf, &new_todo) ||
-	    todo_list_check(todo_list, &new_todo)) {
-		fprintf(stderr, _(edit_todo_list_advice));
+	} else if (res == -4) {
 		checkout_onto(r, opts, onto_name, &onto->object.oid, orig_head);
 		todo_list_release(&new_todo);
 
 		return -1;
 	}
 
+	/* Expand the commit IDs */
+	todo_list_to_strbuf(r, &new_todo, &buf2, -1, 0);
+	strbuf_swap(&new_todo.buf, &buf2);
+	strbuf_release(&buf2);
+	new_todo.total_nr -= new_todo.nr;
+	if (todo_list_parse_insn_buffer(r, new_todo.buf.buf, &new_todo) < 0)
+		BUG("invalid todo list after expanding IDs:\n%s",
+		    new_todo.buf.buf);
+
 	if (opts->allow_ff && skip_unnecessary_picks(r, &new_todo, &oid)) {
 		todo_list_release(&new_todo);
 		return error(_("could not skip unnecessary pick commands"));
@@ -5084,15 +5143,21 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
 		return error_errno(_("could not write '%s'"), todo_file);
 	}
 
-	todo_list_release(&new_todo);
+	res = -1;
 
 	if (checkout_onto(r, opts, onto_name, &oid, orig_head))
-		return -1;
+		goto cleanup;
 
 	if (require_clean_work_tree(r, "rebase", "", 1, 1))
-		return -1;
+		goto cleanup;
 
-	return sequencer_continue(r, opts);
+	todo_list_write_total_nr(&new_todo);
+	res = pick_commits(r, &new_todo, opts);
+
+cleanup:
+	todo_list_release(&new_todo);
+
+	return res;
 }
 
 struct subject2item_entry {
@@ -5169,7 +5234,7 @@ int todo_list_rearrange_squash(struct todo_list *todo_list)
 		*commit_todo_item_at(&commit_todo, item->commit) = item;
 
 		parse_commit(item->commit);
-		commit_buffer = get_commit_buffer(item->commit, NULL);
+		commit_buffer = logmsg_reencode(item->commit, NULL, "UTF-8");
 		find_commit_subject(commit_buffer, &subject);
 		format_subject(&buf, subject, " ");
 		subject = subjects[i] = strbuf_detach(&buf, &subject_len);
@@ -5266,3 +5331,24 @@ int todo_list_rearrange_squash(struct todo_list *todo_list)
 
 	return 0;
 }
+
+int sequencer_determine_whence(struct repository *r, enum commit_whence *whence)
+{
+	if (file_exists(git_path_cherry_pick_head(r))) {
+		struct object_id cherry_pick_head, rebase_head;
+
+		if (file_exists(git_path_seq_dir()))
+			*whence = FROM_CHERRY_PICK_MULTI;
+		if (file_exists(rebase_path()) &&
+		    !get_oid("REBASE_HEAD", &rebase_head) &&
+		    !get_oid("CHERRY_PICK_HEAD", &cherry_pick_head) &&
+		    oideq(&rebase_head, &cherry_pick_head))
+			*whence = FROM_REBASE_PICK;
+		else
+			*whence = FROM_CHERRY_PICK_SINGLE;
+
+		return 1;
+	}
+
+	return 0;
+}