I think it's because you used --squash
. I'm not sure why you did, but you shouldn't need to. From the --squash
documentation for git merge:
Produce the working tree and index state as if a real merge happened, but do not actually make a commit or move the HEAD, nor record $GIT_DIR/MERGE_HEAD to cause the next git commit command to create a merge commit. This allows you to create a single commit on top of the current branch whose effect is the same as merging another branch (or more in case of an octopus).
Basically, you need to do a "proper" merge. Squashing seems to have a rather specific usage situation (one that I've never had, so I can't really comment on why it's useful). I guess it's if you don't want the branch tree to look messy if you did some work in a branch but then decided to just merge it into a different branch that you're doing more overarching work in.