[BUG] rebase -p loses commits

I was trying to reproduce somebody's issue with a minimal test case, and
I ran across this setup wherein "rebase -p" silently drops some commits:

  commit() {
    echo $1 >file && git add file && git commit -m $1
  }

  # repo with two branches, each with conflicting content
  git init repo && cd repo &&
  commit base &&
  commit master &&
  git checkout -b feature HEAD^ &&
  commit feature &&

  # now merge them, with some fake resolution
  ! git merge master &&
  commit resolved &&

  # now try to "rebase -p" on top of master.
  git rebase -p master

The rebase completes successfully, but the "feature" commit and the
merge resolution are gone!

I'm totally unfamiliar with the preserve-merges code, and I won't have
time to dig further until later today or tomorrow, so I thought I'd
throw it out here and see if anybody has any clues.

-Peff

On 05/16/2011 06:33 AM, Jeff King wrote:

I was trying to reproduce somebody's issue with a minimal test case, and
I ran across this setup wherein "rebase -p" silently drops some commits:
  

This particular patch seems to have something to do with the bug:
    d80d6bc146232d81f1bb4bc58e5d89263fd228d4
    http://thread.gmane.org/gmane.comp.version-control.git/98247/focus=98251

However, I can't figure out what the "odd boundary case" that this patch
was supposed to fix is. Anyone have any idea?

Andrew