Additional Type Checks still run after ConvertUsing in 5.0

[richardlawley]

When registering a custom type converter, I would expect no additional checks to be performed when validating the configuration. Instead, an exception is thrown if a type exists that cannot be automatically converted:

public class A
{
    public string Foo { get; set; }
}
public class B
{
    public C Foo { get; set; }
}
public class C { }

[TestMethod]
public void ConvertUsing_IgnoresProperties()
{
    var config = new MapperConfiguration(cfg =>
    {
        cfg.CreateMap<A, B>().ConvertUsing(x => new B { Foo = new C() });
    });
    config.AssertConfigurationIsValid();
}

This generates the following error:

AutoMapper.AutoMapperConfigurationException: The following property on UnitTestProject8.C cannot be mapped:

Add a custom mapping expression, ignore, add a custom resolver, or modify the destination type UnitTestProject8.C.
Context:
Mapping from type System.String to UnitTestProject8.C

Observations:

• The error only occurs on properties which exist in TSrc and TDest
• The error only occurs if there is no mapping between the property types
• No exception is generated if trying to map using this configuration, only on AssertConfigurationIsValid

[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.