Bastien Montagne
2a8122fb65
This function was doing too many things, with behaviors fairly different depending on its input parameters. This was making the code fragile and hard to follow. Split it in three: * `ed_undo_step_pre` does the common actions before we actually undo data. * `ed_undo_step_post` does the common actions after we have undone/redone data. Then, `ed_undo_step_direction`, `ed_undo_step_by_name` and `ed_undo_step_by_index` do their actual specific actions, with their own logic. Note: Since the actual behavior of those three funtions is fairly different (the first only undo/redo one effective step, the second is only supposed to **undo** //before// given named step, and the third actually undo/redo until given indexed step become active), we could also find better names for those. right now, it sounds like they are doing the same thing, with just different ways to specify the target step. Note: This is part of on-going refactor work on undo system, see T83806. Differential Revision: https://developer.blender.org/D10112