@schlessera how to check which step is undefined?

Failure seems unrelated to change:

https://travis-ci.org/github/wp-cli/wp-cli/jobs/708051503#L454-L460
https://travis-ci.org/github/wp-cli/wp-cli/jobs/708051503#L346-L348

@thrijith It looks like there's an instance where the step syntax contains a double space, which is the likely cause of the failure.

@thrijith It looks like there's an instance where the step syntax contains a double space, which is the likely cause of the failure.

Yes, that's it 🙂

@schlessera there is one more in trunk https://travis-ci.org/github/wp-cli/wp-cli/jobs/708222192#L505-L511, but that seems to be the same as you mentioned on #cli

I'll see if I can fix that one today.

Created a Core trac bug report here: https://core.trac.wordpress.org/ticket/50670

I added a new issue for documenting this: #5444.