private void TestAssignmentOnStruct <TTarget, TValue>(ref TTarget input, string memberName, TValue value)
where TTarget : struct
{
// Remember that structs are copied when passed into another method. If we're not careful about how we can construct this test
// we can end up with a scenario in which the tests can never pass because we're modifying a copy of the struct, not the original
// meaning our assertions fail because the modifications were made on a copy
// Be VERY CAREFUL modifying this method to ensure you don't accidently introduce such a regression.
// To avoid this, we need to do two things
// 1. Rather than quoting the value, pass it as a ByRef parameter into a dynamic method
// 2. When creating the Dynamic Expression using the binder,we need to use Expression.MakeDynamic() rather than Expression.Dynamic()
// The delegate created by Expression.Dynamic() doesn't support ByRef parameters, hence why we have to make the delegate ourselves.
// See https://dlr.codeplex.com/discussions/69200 for more details.
var binder = new VelocitySetMemberBinder(memberName, new MemberResolver());
var methodParameter = Expression.Parameter(typeof(TTarget).MakeByRefType());
var delegateType = typeof(StructByReferenceDynamicDelegate <TTarget, TValue>);
var setExpression = Expression.MakeDynamic(delegateType, binder, methodParameter, Expression.Constant(value));
//var setExpression = Expression.Dynamic(binder, typeof(void), structByRefParam, Expression.Constant(value));
var lambda = Expression.Lambda <StructByReferenceExecution <TTarget> >(setExpression, false, new[] { methodParameter });
var method = lambda.Compile();
method(ref input);
}
private void TestAssignmentOnReferenceType <TTarget, TValue>(TTarget input, string memberName, TValue value)
where TTarget : class
{
var binder = new VelocitySetMemberBinder(memberName, new MemberResolver());
InvokeBinder(binder, input, value);
}
