Git, how to "force" a squash rebase

Question

I need to "squash" some commits together. Normally I am used to do something like this:

git rebase -i HEAD~10

However, now I am getting the error below:

error: could not apply 2009972... fixes

When you have resolved this problem, run "git rebase --continue". If you prefer to skip this patch, run "git rebase --skip" instead. To check out the original branch and stop rebasing, run "git rebase --abort".

As you can see git pretends that I resolve all the conflicts. Now, I do not want and cannot resolve any conflicts.

What I need is a way to tell git something like: "Hey, I do not want to merge anything: just take all the tracked files in this branch - as they appear in the last commit/HEAD, discard/remove the previous 10 commits before the latest one, and finally "apply" these files as a new commit":

For example, suppose this is a list of all commits hashes:

1-2-3-4-5-6-7-8-9-10-11-12, where HEAD points to 12.

I want to squash/remove/whatever this operation is called all the commits from 2-11 included, so that the final result after a git log gives:

1-12

where the files before and after the operation must be the same.

What are the commands to obtain what I need?

Answer 1

The simplest solution (after aborting the current rebase) is:

$ git reset --soft HEAD~10

Now, your HEAD has moved ten commits back, but none of your files changed: they'll all show up as new changes to be committed.

Then, just commit them as normal.

---

The downside to this approach is that you lose access to the intermediate commit messages when you're writing your new commit message.

The alternative is to make the original rebase -i command work for you by by specifying conflict resolution strategy theirs:

$ git rebase -i -s theirs HEAD~10

It would be interesting to know how you've managed to get conflicts in the first place though, rebase -i should usually apply cleanly. Unless some of those ten commits are themselves merges?