git push --mirror without pull refs

Question

I'm migrating one git repo to another. To do this I'm using the --mirror flag for both the clone and push operations.

This works, except for a failure at the end, causing my bash script to fail, which appears isolated to pull requests:

! [remote rejected] refs/pull/1/head -> refs/pull/1/head (The current action can only be performed by the system.) ! [remote rejected] refs/pull/1/merge -> refs/pull/1/merge (The current action can only be performed by the system.) ! [remote rejected] refs/pull/2/head -> refs/pull/2/head (The current action can only be performed by the system.) ! [remote rejected] refs/pull/3/head -> refs/pull/3/head (The current action can only be performed by the system.)

Is it necessary to migrate pull requests?

How can I omit the pull requests when I do git push --mirror?

I've seen references to modifying config files, but I'd prefer to handle it at the CLI if at all possible.

Answer 1

Using --mirror directs Git to copy all references, as if by the refspec +refs/*:refs/*. (With git clone it sets up a fetch mirror as well: a bare clone whose default refspec is this same +refs/*:refs/*, with prune enabled by default.)

As you have seen, some Git servers refuse even forced updates to some references. In particular, GitHub reserves the refs/pull/ namespace for its own purposes.

Is it necessary to migrate pull requests?

As far as I know, it's not even possible to do this on GitHub (though of course the GitHub folks might be able to do it from their end).

How can I omit the pull requests when I do git push --mirror?

I think the simplest method would be to delete them after the git clone --mirror step:

git for-each-ref --format 'delete %(refname)' refs/pull | git update-ref --stdin

but you could also explicitly push the references you care about, which probably are just those under refs/heads/ and refs/tags/, and maybe refs/replace/ and/or refs/notes/.