sequencer: refactor sequencer_add_exec_commands() to work on a todo_list

This refactors sequencer_add_exec_commands() to work on a todo_list to
avoid redundant reads and writes to the disk.

Instead of inserting the `exec' commands between the other commands and
re-parsing the buffer at the end, they are appended to the buffer once,
and a new list of items is created.  Items from the old list are copied
across and new `exec' items are appended when necessary.  This
eliminates the need to reparse the buffer, but this also means we have
to use todo_list_write_to_disk() to write the file.

todo_list_add_exec_commands() and sequencer_add_exec_commands() are
modified to take a string list instead of a string -- one item for each
command.  This makes it easier to insert a new command to the todo list
for each command to execute.

sequencer_add_exec_commands() still reads the todo list from the disk,
as it is needed by rebase -p.

complete_action() still uses sequencer_add_exec_commands() for now.
This will be changed in a future commit.

Signed-off-by: Alban Gruin <alban.gruin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/sequencer.h b/sequencer.h
index 217353e9f0..87d04a3b9b 100644
--- a/sequencer.h
+++ b/sequencer.h
@@ -146,12 +146,13 @@ int sequencer_make_script(struct repository *r, FILE *out, int argc,
 			  const char **argv,
 			  unsigned flags);
 
-int sequencer_add_exec_commands(struct repository *r, const char *command);
+int sequencer_add_exec_commands(struct repository *r,
+				struct string_list *commands);
 int transform_todo_file(struct repository *r, unsigned flags);
 int check_todo_list_from_file(struct repository *r);
 int complete_action(struct repository *r, struct replay_opts *opts, unsigned flags,
 		    const char *shortrevisions, const char *onto_name,
-		    const char *onto, const char *orig_head, const char *cmd,
+		    const char *onto, const char *orig_head, struct string_list *commands,
 		    unsigned autosquash);
 int rearrange_squash(struct repository *r);