[PATCH v2 0/2] Make git rebase work with --rebase-merges and --exec

It was reported via IRC that the exec lines are inserted in the wrong spots when using --rebase-merges.

The reason is that we used a simple, incorrect implementation that happened to work as long as the generated todo list only contains pick, fixup and squash commands. Which is not the case with--rebase-merges.

Fix this issue by using a correct, if longer and slightly more complex implementation instead.

Johannes Schindelin (2):
  t3430: demonstrate what -r, --autosquash & --exec should do
  rebase --exec: make it work with --rebase-merges

 sequencer.c              | 37 +++++++++++++++++++++++++++----------
 t/t3430-rebase-merges.sh | 17 +++++++++++++++++
 2 files changed, 44 insertions(+), 10 deletions(-)

base-commit: 1d89318c48d233d52f1db230cf622935ac3c69fa
Published-As: https://github.com/gitgitgadget/git/releases/tags/pr-13%2Fdscho%2Frebase-merges-and-exec-commands-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-13/dscho/rebase-merges-and-exec-commands-v2
Pull-Request: https://github.com/gitgitgadget/git/pull/13

Range-diff vs v1:

 1:  1d82eb450 = 1:  1d82eb450 t3430: demonstrate what -r, --autosquash & --exec should do
 2:  b29c4d979 ! 2:  7ca441a89 rebase --exec: make it work with --rebase-merges
     @@ -38,7 +38,7 @@
       	struct strbuf *buf = &todo_list.buf;
       	size_t offset = 0, commands_len = strlen(commands);
      -	int i, first;
     -+	int i, insert_final_commands;
     ++	int i, insert;
       
       	if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
       		return error(_("could not read '%s'."), todo_file);
     @@ -52,59 +52,38 @@
      -		if (item->command == TODO_PICK && !first) {
      -			strbuf_insert(buf, item->offset_in_buf + offset,
      -				      commands, commands_len);
     --			offset += commands_len;
      +	/*
      +	 * Insert <commands> after every pick. Here, fixup/squash chains
      +	 * are considered part of the pick, so we insert the commands *after*
      +	 * those chains if there are any.
      +	 */
     -+	insert_final_commands = 1;
     -+	for (i = 0; i < todo_list.nr; ) {
     ++	insert = -1;
     ++	for (i = 0; i < todo_list.nr; i++) {
      +		enum todo_command command = todo_list.items[i].command;
     -+		int j = 0;
      +
     -+		if (command != TODO_PICK && command != TODO_MERGE) {
     -+			i++;
     -+			continue;
     -+		}
     -+
     -+		/* skip fixup/squash chain, if any */
     -+		for (i++; i < todo_list.nr; i++, j = 0) {
     -+			command = todo_list.items[i].command;
     -+
     -+			if (is_fixup(command))
     ++		if (insert >= 0) {
     ++			/* skip fixup/squash chains */
     ++			if (command == TODO_COMMENT)
      +				continue;
     -+
     -+			if (command != TODO_COMMENT)
     -+				break;
     -+
     -+			/* skip comment if followed by any fixup/squash */
     -+			for (j = i + 1; j < todo_list.nr; j++)
     -+				if (todo_list.items[j].command != TODO_COMMENT)
     -+					break;
     -+			if (j < todo_list.nr &&
     -+			    is_fixup(todo_list.items[j].command)) {
     -+				i = j;
     ++			else if (is_fixup(command)) {
     ++				insert = i + 1;
      +				continue;
      +			}
     -+			break;
     ++			strbuf_insert(buf,
     ++				      todo_list.items[insert].offset_in_buf +
     ++				      offset, commands, commands_len);
     + 			offset += commands_len;
     ++			insert = -1;
       		}
      -		first = 0;
      +
     -+		if (i >= todo_list.nr) {
     -+			insert_final_commands = 1;
     -+			break;
     -+		}
     -+
     -+		strbuf_insert(buf, todo_list.items[i].offset_in_buf + offset,
     -+			      commands, commands_len);
     -+		offset += commands_len;
     -+		insert_final_commands = 0;
     ++		if (command == TODO_PICK || command == TODO_MERGE)
     ++			insert = i + 1;
       	}
       
       	/* append final <commands> */
      -	strbuf_add(buf, commands, commands_len);
     -+	if (insert_final_commands)
     ++	if (insert >= 0 || !offset)
      +		strbuf_add(buf, commands, commands_len);
       
       	i = write_message(buf->buf, buf->len, todo_file, 0);