Re: [PATCH v5 0/4] history: add squash subcommand to fold a range

Phillip Wood <phillip.wood123@gmail.com> writes:

That's interesting. It at least deserves a warning, even though the choice to leave them out, with intentions to make it a separate fix on top, may be deliberate. If such a change-of-mind-in-the-middle is rare, then erroring out would be perfect. The user can first reword the !fixup to make it a separate fix and then squash the range in quesiton.

I would not recommend guessing what these rev-list "expressions" would produce and blacklist some of the operations and notations. It would be a more robust approach to let the machinery do its thing to determine the set of commits, *and* inspect the shape of the history these commits represent. Are they connected? Do they have a single "bottom" that is just outside and below the range so that we can replace it with the result of squashing everything together? Do they have a single "top" whose children can be rewritten to have the resulting single commit as one of their parents? Starting from the acceptable shape of the history we want to deal with, rather than trying to enumerate rev-list operations and notations that would prevent the resulting set of commits to fall outside the acceptable shape of the history (and I am reasonably sure anybody who attempts to do so would either end up with unusablly narrow subset of what we can reasonably handle, or miss some cases that we do not want to handle), would be a better approach.