Backend config 'branch' option does not work with git-gateway and editorial_workflow.

[gl2748]

Describe the bug
The docs here: ' https://www.netlifycms.org/docs/authentication-backends/
show that branch is a config option for the backend config. However, when using the git-gateway backend with a branch specified like so:

backend:
  name: git-gateway
  branch: cms

You will find that setting the publish_mode setting to be:

backend:
  name: git-gateway
  branch: cms

publish_mode: editorial_workflow

Does not work, when you come to save a draft.

It does not work because as configured the CMS will pass a mal-formed ref like refs/heads/{backend-branch-config-here}/featureA to Github when saving draft content. It should be: refs/heads/featureA.

See:
https://developer.github.com/v3/git/refs/#create-a-reference

To Reproduce
See above.
Expected behavior
backend options should work for all backends.

[erquhart]

It's not passing in the branch config, it uses cms/ as a prefix for branch names, and your branch config happens to be cms. I could have sworn we fixed this at some point, as having a branch named cms disallows our branch naming convention. I'll look for the related issue.

[erquhart]

Yep, here it is: #2331 (comment)

Closing this is as a duplicate of that.