Improved the error messaging for the DangerousAttributeError exception

[aantix]

When the DangerousAttributeError exception is thrown, it's not entirely clear where the conflict is originating from. Now the user is alerted that the conflict is a similarly named column.

I ran into this issue the other day when a column "valid" was added via a migration. I received the message:

valid? is defined by Active Record

By the looks of that message, I thought that I had created a method called valid? on my model (which wasn't the case). It took me a while to track down that a column named 'valid' had been added to the table via a migration.

[schneems]

Seems reasonable

[senny]

This could cause confusion when the conflicting method is not a column on the models table. For example when defining an enum we make sure that the methods generated by the chosen states do not conflict. This will result in an error message suggesting you rename a column that doesn't exist.

[aantix]

@senny, I've added additional logic so that the rename column suggestion is only output when it's actually a column in conflict.

[rafaelfranca]

I don't think we should add logic to this warning. We can come up with a more generic message? Something like:

raise DangerousAttributeError, "#{method_name} is defined by Active Record. Check if you don't have any attribute or method with the same name"

[senny]

I'm with @rafaelfranca on this one. A generic message that gives hints to what could be the cause is fine but I'd rather not add any logic. At the point where this warning is raised the mistake has already been made. What would be nice is a warning when running migrations that add colliding columns. Would be a bigger change though.

[aantix]

@rafaelfranca @senny Good points. I'll make the changes for @rafaelfranca suggestion.

[aantix]

@rafaelfranca Updated with clearer messaging and logic removed.

[rafaelfranca]

Could you squash your commits?

[aantix]

Squashed.

[rafaelfranca]

Thanks