Running this:
curl -u user:pwd -X PUT -H "Accept: application/json" -H "Content-type: application/json" -d "{\"name\":\"development\"}" http://git.somewhere.com/rest/api/1.0/projects/TM/repos/myrepo/branches/default
Yields this:
{"errors":[{"context":"name","message":"Unrecognized field \"name\" (Class com.atlassian.stash.rest.data.RestBranch), not marked as ignorable\n at [Source: org.apache.catalina.connector.CoyoteInputStream@18c82cf; line: 1, column: 10] (through reference chain: com.atlassian.stash.rest.data.RestBranch[\"name\"])","exceptionName":null}]}
The API browser offers no suggestion of what the field name is supposed to be. I've tried 'branch' and 'default' as the field name, neither of which work.