KeyError: 'dx_News Item__for__NewsItem' in @@custom_migration

[fulv]

I'm using 1.1b6 on Plone 4.3.7.

https://github.com/plone/plone.app.contenttypes/blob/1.1b6/plone/app/contenttypes/migration/custom_migration.py#L241

It seems that safe_dx is not that safe, after all. Indeed:

(Pdb) dx_typename
'News Item'

2015-12-07 18:06:07 ERROR Zope.SiteErrorLog 1449540367.650.827755354863 http://localhost:8080/Plone/@@custom_migration
Traceback (innermost last):
  Module ZPublisher.Publish, line 138, in publish
  Module ZPublisher.mapply, line 77, in mapply
  Module ZPublisher.Publish, line 48, in call_object
  Module plone.app.contenttypes.migration.custom_migration, line 46, in __call__
  Module plone.app.contenttypes.migration.custom_migration, line 241, in migrate
KeyError: 'dx_News Item__for__NewsItem'

[fulv]

This is how I got it to work:
1.1b6...fulv-305

I'm sure it's horrible, but hopefully it will save you some time.

[pbauer]

I'm waiting for @rockfruit to fix his pull-request #284. That fixes this issue.

[pbauer]

I gave up on waiting and backported it myself. Fixed.

[gianniftp]

Plone 5.0.10 , python 2.7.18. trying to migrate to plone 5.2...
when i try to use the @@custom_migration form i have the same problem with wrong space replace . i found this issue closed. i followed the trace trough #284 and #307 and i went in dead end as the cherry picking was in 1.1.x but not from 1.2.x on.