4.2.0 .Include<DerivedSourceType, DerivedTargetType> throws exception with base type names

[PehrGit]

Creating a map and including a map which doesn't exist throws an exception that doesn't really help find the missing map.

Consider the following:

`

    public class SourceDerived
    {
    }

    public interface IMyInterface
    {
    }

    public class TargetDerived : IMyInterface
    {
    }

    [TestMethod]
    public void MyTestMethod()
    {
        var config = new MapperConfiguration(cfg =>
            cfg.CreateMap<object, IMyInterface>()
                .Include<SourceDerived, TargetDerived>()
            );
    }

`
The test throws an exception with message :

System.InvalidOperationException: Missing map from Object to IMyInterface. Create using Mapper.CreateMap<Object, IMyInterface>.

It is right to throw because I have not defined a map from SourceDerived to TargetDerived.

In my opinion it would be much more helpful if the message read:

System.InvalidOperationException: Missing map from SourceDerived to TargetDerived. Create using Mapper.CreateMap<SourceDerived , TargetDerived>.

@jbogard If you agree, I would happily provide a PR

[jbogard]

Anything that you "Include" has to include its own CreateMap call. Them's the rules.

[lbargaoanu]

@jbogard @PehrGit means this.

[jbogard]

[lbargaoanu]

:)

[PehrGit]

@lbargaoanu @jbogard That's sort of what I mean, but my point is actually that that test asserts that the message contains the name of the base type, not the derived type.

This:

ex=>ex.Message.ShouldStartWith("Missing map from Object to BaseType."));

Should be, in my humble opinion:

ex=>ex.Message.ShouldStartWith("Missing map from Object to ChildType."));

[lbargaoanu]

Yes, the original test was wrong.

[PehrGit]

Yay I helped!

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.