Any tests for a type which is not overridden by Active Record, and does
not test the specifics of the attributes API interacting in more complex
ways have no reason to be in the Active Record suite. Doing this
revealed that the implementation of the date and time types in AM was
actually completely broken, and incapable of returning any value other
than `nil`.
Given that this was originally added to normalize an error that would
have otherwise come from the database (inconsistently), it's more
natural for us to raise in `type_cast_for_database`, rather than
`type_cast_from_user`. This way, things like numericality validators can
handle it instead if the user chooses to do so. It also fixes an issue
where assigning an out of range value would make it impossible to assign
a new value later.
This fixes several vague issues, none of which were ever directly
reported, so I have no issue number to give. Places it was mentioned
which I can remember:
- 9ba21381d7/lib/shoulda/matchers/active_model/allow_value_matcher.rb (L261-L263)
- https://github.com/rails/rails/issues/18653#issuecomment-71197026
Kir Shatrov