public void Simple_Serialize()
        {
            var surrogate = new SurrogateTypeDescriber(false);

            surrogate.AddSurrogateType(typeof(_Simple_Real).GetTypeInfo(), typeof(_Simple_Surrogate).GetTypeInfo());

            // maps!
            {
                var res = surrogate.EnumerateMembersToSerialize(typeof(_Simple_Real).GetTypeInfo());

                Assert.Collection(
                    res,
                    a =>
                {
                    Assert.True(a.EmitDefaultValue);
                    Assert.Null(a.Field);
                    Assert.Equal(SerializableMember.GetDefaultFormatter(typeof(string).GetTypeInfo()), a.Formatter);
                    Assert.Equal("bar", a.Name);
                    Assert.Equal(typeof(_Simple_Real).GetProperty(nameof(_Simple_Real.Foo)).GetMethod, a.Getter);
                    Assert.Null(a.ShouldSerialize);
                }
                    );
            }

            // doesn't map
            {
                var res = surrogate.EnumerateMembersToSerialize(typeof(_Simple_Surrogate).GetTypeInfo());

                Assert.Collection(
                    res,
                    a =>
                {
                    Assert.True(a.EmitDefaultValue);
                    Assert.Null(a.Field);
                    Assert.Equal(SerializableMember.GetDefaultFormatter(typeof(string).GetTypeInfo()), a.Formatter);
                    Assert.Equal("bar", a.Name);
                    Assert.Equal(typeof(_Simple_Surrogate).GetProperty(nameof(_Simple_Surrogate.Foo)).GetMethod, a.Getter);
                    Assert.Null(a.ShouldSerialize);
                }
                    );
            }
        }
        public void Errors()
        {
            // null inner describer
            {
                Assert.ThrowsAny <Exception>(() => new SurrogateTypeDescriber(null, false));
            }

            // null forType
            {
                var s = new SurrogateTypeDescriber(false);
                Assert.ThrowsAny <Exception>(() => s.AddSurrogateType(null, typeof(_Simple_Real).GetTypeInfo()));
            }

            // null surrogateType
            {
                var s = new SurrogateTypeDescriber(false);
                Assert.ThrowsAny <Exception>(() => s.AddSurrogateType(typeof(_Simple_Real).GetTypeInfo(), null));
            }

            // same registration
            {
                var s = new SurrogateTypeDescriber(false);
                Assert.ThrowsAny <Exception>(() => s.AddSurrogateType(typeof(_Simple_Real).GetTypeInfo(), typeof(_Simple_Real).GetTypeInfo()));
            }

            // double registration
            {
                var s = new SurrogateTypeDescriber(false);
                s.AddSurrogateType(typeof(_Simple_Real).GetTypeInfo(), typeof(_Simple_Surrogate).GetTypeInfo());

                Assert.ThrowsAny <Exception>(() => s.AddSurrogateType(typeof(_Simple_Real).GetTypeInfo(), typeof(_Simple_Surrogate).GetTypeInfo()));
            }

            // no registration
            {
                var s = new SurrogateTypeDescriber(true);
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(object).GetTypeInfo()).ToList());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(object).GetTypeInfo()).ToList());
            }

            // field missing
            {
                var s = new SurrogateTypeDescriber(false);
                s.AddSurrogateType(typeof(_Errors_Field).GetTypeInfo(), typeof(_Errors_Field_Missing).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_Field).GetTypeInfo()).ToList());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_Field).GetTypeInfo()).ToList());
            }

            // field type mismatch
            {
                var s = new SurrogateTypeDescriber(false);
                s.AddSurrogateType(typeof(_Errors_Field).GetTypeInfo(), typeof(_Errors_Field_Mismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_Field).GetTypeInfo()).ToList());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_Field).GetTypeInfo()).ToList());
            }

            // prop missing
            {
                var s = new SurrogateTypeDescriber(false);
                s.AddSurrogateType(typeof(_Errors_Property).GetTypeInfo(), typeof(_Errors_Property_Missing).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_Property).GetTypeInfo()).ToList());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_Property).GetTypeInfo()).ToList());
            }

            // prop type mismatch
            {
                var s = new SurrogateTypeDescriber(false);
                s.AddSurrogateType(typeof(_Errors_Property).GetTypeInfo(), typeof(_Errors_Property_Mismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_Property).GetTypeInfo()).ToList());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_Property).GetTypeInfo()).ToList());
            }

            // explicit setter mismatch
            {
                var i = new ManualTypeDescriber(false);
                i.AddExplicitSetter(typeof(_Errors_ExplicitSetter_Mismatch).GetTypeInfo(), "Val", typeof(_Errors_ExplicitSetter_Mismatch).GetMethod("SetVal"));

                var s = new SurrogateTypeDescriber(i, false);
                s.AddSurrogateType(typeof(_Errors_ExplicitSetter).GetTypeInfo(), typeof(_Errors_ExplicitSetter_Mismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_ExplicitSetter).GetTypeInfo()).ToList());
            }

            // explicit static setter mismatch
            {
                var i = new ManualTypeDescriber(false);
                i.AddExplicitSetter(typeof(_Errors_ExplicitStaticSetter_Mismatch).GetTypeInfo(), "Val", typeof(_Errors_ExplicitStaticSetter_Mismatch).GetMethod("SetVal"));

                var s = new SurrogateTypeDescriber(i, false);
                s.AddSurrogateType(typeof(_Errors_ExplicitStaticSetter).GetTypeInfo(), typeof(_Errors_ExplicitStaticSetter_Mismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_ExplicitStaticSetter).GetTypeInfo()).ToList());
            }

            // explicit static setter arity mismatch
            {
                var i = new ManualTypeDescriber(false);
                i.AddExplicitSetter(typeof(_Errors_ExplicitStaticSetter_ArityMismatch).GetTypeInfo(), "Val", typeof(_Errors_ExplicitStaticSetter_ArityMismatch).GetMethod("SetVal"));

                var s = new SurrogateTypeDescriber(i, false);
                s.AddSurrogateType(typeof(_Errors_ExplicitStaticSetter).GetTypeInfo(), typeof(_Errors_ExplicitStaticSetter_ArityMismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToDeserialize(typeof(_Errors_ExplicitStaticSetter).GetTypeInfo()).ToList());
            }

            // explicit getter mismatch
            {
                var i = new ManualTypeDescriber(false);
                i.AddExplicitGetter(typeof(_Errors_ExplicitGetter_Mismatch).GetTypeInfo(), "Val", typeof(_Errors_ExplicitGetter_Mismatch).GetMethod("GetVal"));

                var s = new SurrogateTypeDescriber(i, false);
                s.AddSurrogateType(typeof(_Errors_ExplicitGetter).GetTypeInfo(), typeof(_Errors_ExplicitGetter_Mismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_ExplicitGetter).GetTypeInfo()).ToList());
            }

            // explicit static getter mismatch
            {
                var i = new ManualTypeDescriber(false);
                i.AddExplicitGetter(typeof(_Errors_ExplicitStaticGetter_Mismatch).GetTypeInfo(), "Val", typeof(_Errors_ExplicitStaticGetter_Mismatch).GetMethod("GetVal"));

                var s = new SurrogateTypeDescriber(i, false);
                s.AddSurrogateType(typeof(_Errors_ExplicitStaticGetter).GetTypeInfo(), typeof(_Errors_ExplicitStaticGetter_Mismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_ExplicitStaticGetter).GetTypeInfo()).ToList());
            }

            // explicit static getter arity mismatch
            {
                var i = new ManualTypeDescriber(false);
                i.AddExplicitGetter(typeof(_Errors_ExplicitStaticGetter_ArityMismatch).GetTypeInfo(), "Val", typeof(_Errors_ExplicitStaticGetter_ArityMismatch).GetMethod("GetVal"));

                var s = new SurrogateTypeDescriber(i, false);
                s.AddSurrogateType(typeof(_Errors_ExplicitStaticGetter).GetTypeInfo(), typeof(_Errors_ExplicitStaticGetter_ArityMismatch).GetTypeInfo());
                Assert.ThrowsAny <Exception>(() => s.EnumerateMembersToSerialize(typeof(_Errors_ExplicitStaticGetter).GetTypeInfo()).ToList());
            }
        }