Discussed with abayer on #jenkins, he asked me to make a JIRA ticket for this.
I upgraded from pipeline model definition ~1.0 to 1.1.2, and my pipelines broke.
Specifically, the following escaped double quoting does not work any more: https://github.com/WillowChat/Hopper/blob/6e13089d9b9a0b61030d1ee3a7d949d7ac14b8fe/Jenkinsfile#L23
But the same line with single quotes does: https://github.com/WillowChat/Hopper/blob/90eb695051405fadc818cf365a1ed7571ce1f645/Jenkinsfile#L23
The error log is available here, it looks like it's trying to resolve the branch name (which is `develop`), which results in a confusing Groovy binding error message: https://ci.carrot.codes/job/Willow%20Chat/job/Hopper/job/develop/6/console
(And in case that log disappears for some reason)
groovy.lang.MissingPropertyException: No such property: develop for class: groovy.lang.Binding