Errors if book.settings allowed_types is not configured

The merge request has a partial fix, fixing book_type_is_allowed().

Fixes should go against 2.0.x first

Re-rolled against 2.0.x.

I tried replicating on a fresh install with 2.0.x branch of book and not able to replicate.

Maybe need clearer steps for triggering it.

I don't know how we ended-up in this situation. It is clear from the code that this would happen anytime that allowed_types is not an array. People could end up like this by setting it to null or to a string.

Attitude isn't needed and will only delay this issue. How are you setting it to null, maybe write a functional test case to show the problem

smustgrave → closed merge request !75

allowed_types could have been set to something other than an array using Drush. Someone could do this if they want to make it empty but don't realize that it needs to be an empty array and not NULL. It could also happen if a config import is not setup correctly.

The proposed change is designed to make it so that it doesn't matter if allowed_types is not an array. No error will be created.

Added steps to reproduce.

Bad drush command not sure counts. If it can replicated via a workflow let’s add test coverage