Version 4.3.1 - ArgumentError: Polymorphic association does not support to compute class.

[DannyBen]

After upgrading from 4.2.0 to 4.3.1 I am getting this error during my tests.

ArgumentError: Polymorphic association does not support to compute class.

• The error is triggered from the model's comma block.
• The model has a polymorphic association created by the audited gem.
• I have tried removing the associated columns from my comma model definition to see if it helps, it did not.
• Version 4.3.0 is also affected
• Ruby 2.5.3, Rails 5.2.2.1

[eitoball]

Could you provide smallest code sample to reproduce this issue? A sample repository on GitHub would be nice. Thank you.

[DannyBen]

I can try to create a minimal new rails app, hopefully it will reproduce.

[DannyBen]

I have managed to reproduce it with a plain new Rails app.

The repository is here, and its README has both simple usage instructions and steps taken to build the app.

[DannyBen]

Thanks for the super quick fix.