Support 'Object operator ==(dynamic other))'

[quanbui1998]

I use a library but it is write a class which override operator ==(dynamic other) so dart display error:

'Object.==' ('bool Function(Object)') isn't a valid concrete implementation of 'Record.==' ('bool Function(dynamic)').

@override
  bool operator ==(dynamic other) {
     ...
  }

Can you fix mockito for support operator ==(dynamic other)? Thanks!

[eernstg]

I'm not working on mockito, but here is a comment from a Dart language perspective:

With null safety (that is, since language version 2.12), operator == accepts an argument of type Object. It is possible to create an override whose signature is bool operator ==(dynamic), but that is misleading and unnecessary because the semantics of e1 == e2 ensures that the operator == will never be invoked with null as the actual argument.

I don't know the details of your code, but the problem probably arises when a class has an interface where operator == has a parameter of type dynamic, and it inherits an implementation whose parameter type is Object. That is not a correct override (because that implementation should be able to accept null as its argument, but it cannot do that).

So the fix would be to get that declaration of operator ==(dynamic arg) fixed.

[natebosch]

I'll close this since there is a workaround and it isn't a pattern we'd like to encourage.