Merge branch 'pw/rebase-i-show-HEAD-to-reword'

"git rebase -i" showed a wrong HEAD while "reword" open the editor.

* pw/rebase-i-show-HEAD-to-reword:
  sequencer: simplify root commit creation
  rebase -i: check for updated todo after squash and reword
  rebase -i: always update HEAD before rewording

sequencer.c

@@ -869,34 +869,6 @@ static char *get_author(const char *message)
 	return NULL;
 }
 
-/* Read author-script and return an ident line (author <email> timestamp) */
-static const char *read_author_ident(struct strbuf *buf)
-{
-	struct strbuf out = STRBUF_INIT;
-	char *name, *email, *date;
-
-	if (read_author_script(rebase_path_author_script(),
-			       &name, &email, &date, 0))
-		return NULL;
-
-	/* validate date since fmt_ident() will die() on bad value */
-	if (parse_date(date, &out)){
-		warning(_("invalid date format '%s' in '%s'"),
-			date, rebase_path_author_script());
-		strbuf_release(&out);
-		return NULL;
-	}
-
-	strbuf_reset(&out);
-	strbuf_addstr(&out, fmt_ident(name, email, WANT_AUTHOR_IDENT, date, 0));
-	strbuf_swap(buf, &out);
-	strbuf_release(&out);
-	free(name);
-	free(email);
-	free(date);
-	return buf->buf;
-}
-
 static const char staged_changes_advice[] =
 N_("you have staged changes in your working tree\n"
 "If these changes are meant to be squashed into the previous commit, run:\n"
@@ -954,47 +926,6 @@ static int run_git_commit(struct repository *r,
 {
 	struct child_process cmd = CHILD_PROCESS_INIT;
 
-	if ((flags & CREATE_ROOT_COMMIT) && !(flags & AMEND_MSG)) {
-		struct strbuf msg = STRBUF_INIT, script = STRBUF_INIT;
-		const char *author = NULL;
-		struct object_id root_commit, *cache_tree_oid;
-		int res = 0;
-
-		if (is_rebase_i(opts)) {
-			author = read_author_ident(&script);
-			if (!author) {
-				strbuf_release(&script);
-				return -1;
-			}
-		}
-
-		if (!defmsg)
-			BUG("root commit without message");
-
-		if (!(cache_tree_oid = get_cache_tree_oid(r->index)))
-			res = -1;
-
-		if (!res)
-			res = strbuf_read_file(&msg, defmsg, 0);
-
-		if (res <= 0)
-			res = error_errno(_("could not read '%s'"), defmsg);
-		else
-			res = commit_tree(msg.buf, msg.len, cache_tree_oid,
-					  NULL, &root_commit, author,
-					  opts->gpg_sign);
-
-		strbuf_release(&msg);
-		strbuf_release(&script);
-		if (!res) {
-			update_ref(NULL, "CHERRY_PICK_HEAD", &root_commit, NULL,
-				   REF_NO_DEREF, UPDATE_REFS_MSG_ON_ERR);
-			res = update_ref(NULL, "HEAD", &root_commit, NULL, 0,
-					 UPDATE_REFS_MSG_ON_ERR);
-		}
-		return res < 0 ? error(_("writing root commit")) : 0;
-	}
-
 	cmd.git_cmd = 1;
 
 	if (is_rebase_i(opts) && read_env_script(&cmd.env_array)) {
@@ -1378,7 +1309,7 @@ static int try_to_commit(struct repository *r,
 			 struct object_id *oid)
 {
 	struct object_id tree;
-	struct commit *current_head;
+	struct commit *current_head = NULL;
 	struct commit_list *parents = NULL;
 	struct commit_extra_header *extra = NULL;
 	struct strbuf err = STRBUF_INIT;
@@ -1413,7 +1344,8 @@ static int try_to_commit(struct repository *r,
 		}
 		parents = copy_commit_list(current_head->parents);
 		extra = read_commit_extra_headers(current_head, exclude_gpgsig);
-	} else if (current_head) {
+	} else if (current_head &&
+		   (!(flags & CREATE_ROOT_COMMIT) || (flags & AMEND_MSG))) {
 		commit_list_insert(current_head, &parents);
 	}
 
@@ -1490,8 +1422,7 @@ static int do_commit(struct repository *r,
 {
 	int res = 1;
 
-	if (!(flags & EDIT_MSG) && !(flags & VERIFY_MSG) &&
-	    !(flags & CREATE_ROOT_COMMIT)) {
+	if (!(flags & EDIT_MSG) && !(flags & VERIFY_MSG)) {
 		struct object_id oid;
 		struct strbuf sb = STRBUF_INIT;
 
@@ -1775,7 +1706,7 @@ static int do_pick_commit(struct repository *r,
 			  enum todo_command command,
 			  struct commit *commit,
 			  struct replay_opts *opts,
-			  int final_fixup)
+			  int final_fixup, int *check_todo)
 {
 	unsigned int flags = opts->edit ? EDIT_MSG : 0;
 	const char *msg_file = opts->edit ? NULL : git_path_merge_msg(r);
@@ -1785,7 +1716,7 @@ 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, allow;
+	int res, unborn = 0, reword = 0, allow;
 
 	if (opts->no_commit) {
 		/*
@@ -1855,7 +1786,7 @@ static int do_pick_commit(struct repository *r,
 			opts);
 		if (res || command != TODO_REWORD)
 			goto leave;
-		flags |= EDIT_MSG | AMEND_MSG | VERIFY_MSG;
+		reword = 1;
 		msg_file = NULL;
 		goto fast_forward_edit;
 	}
@@ -1913,7 +1844,7 @@ static int do_pick_commit(struct repository *r,
 	}
 
 	if (command == TODO_REWORD)
-		flags |= EDIT_MSG | VERIFY_MSG;
+		reword = 1;
 	else if (is_fixup(command)) {
 		if (update_squash_messages(r, command, commit, opts))
 			return -1;
@@ -1997,13 +1928,21 @@ static int do_pick_commit(struct repository *r,
 	} else if (allow)
 		flags |= ALLOW_EMPTY;
 	if (!opts->no_commit) {
-fast_forward_edit:
 		if (author || command == TODO_REVERT || (flags & AMEND_MSG))
 			res = do_commit(r, msg_file, author, opts, flags);
 		else
 			res = error(_("unable to parse commit author"));
+		*check_todo = !!(flags & EDIT_MSG);
+		if (!res && reword) {
+fast_forward_edit:
+			res = run_git_commit(r, NULL, opts, EDIT_MSG |
+					     VERIFY_MSG | AMEND_MSG |
+					     (flags & ALLOW_EMPTY));
+			*check_todo = 1;
+		}
 	}
 
+
 	if (!res && final_fixup) {
 		unlink(rebase_path_fixup_msg());
 		unlink(rebase_path_squash_msg());
@@ -3828,6 +3767,7 @@ static int pick_commits(struct repository *r,
 	while (todo_list->current < todo_list->nr) {
 		struct todo_item *item = todo_list->items + todo_list->current;
 		const char *arg = todo_item_get_arg(todo_list, item);
+		int check_todo = 0;
 
 		if (save_todo(todo_list, opts))
 			return -1;
@@ -3866,7 +3806,8 @@ static int pick_commits(struct repository *r,
 					command_to_string(item->command), NULL),
 					1);
 			res = do_pick_commit(r, item->command, item->commit,
-					opts, is_final_fixup(todo_list));
+					     opts, is_final_fixup(todo_list),
+					     &check_todo);
 			if (is_rebase_i(opts) && res < 0) {
 				/* Reschedule */
 				advise(_(rescheduled_advice),
@@ -3923,7 +3864,6 @@ static int pick_commits(struct repository *r,
 		} else if (item->command == TODO_EXEC) {
 			char *end_of_arg = (char *)(arg + item->arg_len);
 			int saved = *end_of_arg;
-			struct stat st;
 
 			if (!opts->verbose)
 				term_clear_line();
@@ -3934,17 +3874,8 @@ static int pick_commits(struct repository *r,
 			if (res) {
 				if (opts->reschedule_failed_exec)
 					reschedule = 1;
-			} else if (stat(get_todo_path(opts), &st))
-				res = error_errno(_("could not stat '%s'"),
-						  get_todo_path(opts));
-			else if (match_stat_data(&todo_list->stat, &st)) {
-				/* Reread the todo file if it has changed. */
-				todo_list_release(todo_list);
-				if (read_populate_todo(r, todo_list, opts))
-					res = -1; /* message was printed */
-				/* `current` will be incremented below */
-				todo_list->current = -1;
 			}
+			check_todo = 1;
 		} else if (item->command == TODO_LABEL) {
 			if ((res = do_label(r, arg, item->arg_len)))
 				reschedule = 1;
@@ -3980,6 +3911,20 @@ static int pick_commits(struct repository *r,
 							item->commit,
 							arg, item->arg_len,
 							opts, res, 0);
+		} else if (check_todo && !res) {
+			struct stat st;
+
+			if (stat(get_todo_path(opts), &st)) {
+				res = error_errno(_("could not stat '%s'"),
+						  get_todo_path(opts));
+			} else if (match_stat_data(&todo_list->stat, &st)) {
+				/* Reread the todo file if it has changed. */
+				todo_list_release(todo_list);
+				if (read_populate_todo(r, todo_list, opts))
+					res = -1; /* message was printed */
+				/* `current` will be incremented below */
+				todo_list->current = -1;
+			}
 		}
 
 		todo_list->current++;
@@ -4306,9 +4251,12 @@ static int single_pick(struct repository *r,
 		       struct commit *cmit,
 		       struct replay_opts *opts)
 {
+	int check_todo;
+
 	setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
 	return do_pick_commit(r, opts->action == REPLAY_PICK ?
-		TODO_PICK : TODO_REVERT, cmit, opts, 0);
+			      TODO_PICK : TODO_REVERT, cmit, opts, 0,
+			      &check_todo);
 }
 
 int sequencer_pick_revisions(struct repository *r,

t/t3404-rebase-interactive.sh

@@ -1014,9 +1014,9 @@ test_expect_success 'rebase -i --root fixup root commit' '
 	test 0 = $(git cat-file commit HEAD | grep -c ^parent\ )
 '
 
-test_expect_success 'rebase -i --root reword root commit' '
+test_expect_success 'rebase -i --root reword original root commit' '
 	test_when_finished "test_might_fail git rebase --abort" &&
-	git checkout -b reword-root-branch master &&
+	git checkout -b reword-original-root-branch master &&
 	set_fake_editor &&
 	FAKE_LINES="reword 1 2" FAKE_COMMIT_MESSAGE="A changed" \
 	git rebase -i --root &&
@@ -1024,6 +1024,16 @@ test_expect_success 'rebase -i --root reword root commit' '
 	test -z "$(git show -s --format=%p HEAD^)"
 '
 
+test_expect_success 'rebase -i --root reword new root commit' '
+	test_when_finished "test_might_fail git rebase --abort" &&
+	git checkout -b reword-now-root-branch master &&
+	set_fake_editor &&
+	FAKE_LINES="reword 3 1" FAKE_COMMIT_MESSAGE="C changed" \
+	git rebase -i --root &&
+	git show HEAD^ | grep "C changed" &&
+	test -z "$(git show -s --format=%p HEAD^)"
+'
+
 test_expect_success 'rebase -i --root when root has untracked file conflict' '
 	test_when_finished "reset_rebase" &&
 	git checkout -b failing-root-pick A &&
@@ -1052,7 +1062,7 @@ test_expect_success 'rebase -i --root reword root when root has untracked file c
 '
 
 test_expect_success C_LOCALE_OUTPUT 'rebase --edit-todo does not work on non-interactive rebase' '
-	git checkout reword-root-branch &&
+	git checkout reword-original-root-branch &&
 	git reset --hard &&
 	git checkout conflict-branch &&
 	set_fake_editor &&

t/t3429-rebase-edit-todo.sh

@@ -3,9 +3,15 @@
 test_description='rebase should reread the todo file if an exec modifies it'
 
 . ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-rebase.sh
+
+test_expect_success 'setup' '
+	test_commit first file &&
+	test_commit second file &&
+	test_commit third file
+'
 
 test_expect_success 'rebase exec modifies rebase-todo' '
-	test_commit initial &&
 	todo=.git/rebase-merge/git-rebase-todo &&
 	git rebase HEAD -x "echo exec touch F >>$todo" &&
 	test -e F
@@ -33,4 +39,17 @@ test_expect_success SHA1 'loose object cache vs re-reading todo list' '
 	git rebase HEAD -x "./append-todo.sh 5 6"
 '
 
+test_expect_success 'todo is re-read after reword and squash' '
+	write_script reword-editor.sh <<-\EOS &&
+	GIT_SEQUENCE_EDITOR="echo \"exec echo $(cat file) >>actual\" >>" \
+		git rebase --edit-todo
+	EOS
+
+	test_write_lines first third >expected &&
+	set_fake_editor &&
+	GIT_SEQUENCE_EDITOR="$EDITOR" FAKE_LINES="reword 1 squash 2 fixup 3" \
+		GIT_EDITOR=./reword-editor.sh git rebase -i --root third &&
+	test_cmp expected actual
+'
+
 test_done

t/t7505-prepare-commit-msg-hook.sh

@@ -241,13 +241,7 @@ test_rebase () {
 			git add b &&
 			git rebase --continue
 		) &&
-		if test "$mode" = -p # reword amended after pick
-		then
-			n=18
-		else
-			n=17
-		fi &&
-		git log --pretty=%s -g -n$n HEAD@{1} >actual &&
+		git log --pretty=%s -g -n18 HEAD@{1} >actual &&
 		test_cmp "$TEST_DIRECTORY/t7505/expected-rebase${mode:--i}" actual
 	'
 }

t/t7505/expected-rebase-i

@@ -7,7 +7,8 @@ message (no editor) [edit rebase-10]
 message [fixup rebase-9]
 message (no editor) [fixup rebase-8]
 message (no editor) [squash rebase-7]
-message [reword rebase-6]
+HEAD [reword rebase-6]
+message (no editor) [reword rebase-6]
 message [squash rebase-5]
 message (no editor) [fixup rebase-4]
 message (no editor) [pick rebase-3]