Investigate the option to create a mock/spy in-place

[picimako]

Summary

When implementing unit tests and mocking certain method calls, one may take the route of writing the code how it may look with possible arguments, names, structure, and such. Then, proceed to creating the written variables, methods, types, etc.

To simplify mock creation, intention actions could be implemented for error elements to create mock/spy local variables or fields based on the type of the method argument at hand.

Tasks

• Create intention action(s) that could create mock/spy local variables and fields from method argument error elements.
• The intention action would probably present an option where to create the mock/spy object, and users could choose.
• If the method argument type cannot be resolved, an error message would appear that the variable/field cannot be created.