public int Compare(ConstructorInfo lhs, ConstructorInfo rhs)
{
if (lhs == rhs)
{
return(0);
}
Debug.Assert(lhs.DeclaringType == rhs.DeclaringType, "Can only compare constructors for the same type.");
var lhsParameters = lhs.GetParameters();
var rhsParameters = rhs.GetParameters();
var lhsUnresolvableParameters = lhsParameters.Where(p => !_engine.CanResolveParameterValue(p, _resolver)).ToArray();
var rhsUnresolvableParameters = rhsParameters.Where(p => !_engine.CanResolveParameterValue(p, _resolver)).ToArray();
var lhsResolvableParameterCount = lhsParameters.Length - lhsUnresolvableParameters.Length;
var rhsResolvableParameterCount = rhsParameters.Length - rhsUnresolvableParameters.Length;
var lhsUnresolvableParameterWithDefaultValueCount = lhsUnresolvableParameters.Count(p => p.HasDefaultValue);
var rhsUnresolvableParameterWithDefaultValueCount = rhsUnresolvableParameters.Count(p => p.HasDefaultValue);
var lhsUnresolvableParameterWithoutDefaultValueCount = lhsUnresolvableParameters.Length - lhsUnresolvableParameterWithDefaultValueCount;
var rhsUnresolvableParameterWithoutDefaultValueCount = rhsUnresolvableParameters.Length - rhsUnresolvableParameterWithDefaultValueCount;
if (lhsUnresolvableParameterWithoutDefaultValueCount < rhsUnresolvableParameterWithoutDefaultValueCount)
{
return(-1);
}
if (lhsUnresolvableParameterWithoutDefaultValueCount > rhsUnresolvableParameterWithoutDefaultValueCount)
{
return(1);
}
if (lhsResolvableParameterCount > rhsResolvableParameterCount)
{
return(-1);
}
if (lhsResolvableParameterCount < rhsResolvableParameterCount)
{
return(1);
}
var commonParameterNames = lhsParameters.Where(lp => rhsParameters.Any(rp => lp.Name == rp.Name)).Select(p => p.Name).OrderBy(n => n).ToArray();
var lhsCommonParameters = commonParameterNames.Select(n => lhsParameters.Single(p => p.Name == n)).ToArray();
var rhsCommonParameters = commonParameterNames.Select(n => rhsParameters.Single(p => p.Name == n)).ToArray();
var score = 0;
for (int i = 0; i < commonParameterNames.Length; i++)
{
var lhsParameterType = Nullable.GetUnderlyingType(lhsCommonParameters[i].ParameterType) ?? lhsCommonParameters[i].ParameterType;
var rhsParameterType = Nullable.GetUnderlyingType(rhsCommonParameters[i].ParameterType) ?? rhsCommonParameters[i].ParameterType;
if (lhsParameterType == rhsParameterType)
{
continue;
}
if (rhsParameterType.IsLessSpecificThan(lhsParameterType))
{
score--;
}
if (lhsParameterType.IsLessSpecificThan(rhsParameterType))
{
score++;
}
}
if (score < 0)
{
return(-1);
}
if (score > 0)
{
return(1);
}
if (lhsUnresolvableParameterWithDefaultValueCount < rhsUnresolvableParameterWithDefaultValueCount)
{
return(-1);
}
if (lhsUnresolvableParameterWithDefaultValueCount > rhsUnresolvableParameterWithDefaultValueCount)
{
return(1);
}
//if (lhs.GetConstructorChain().Contains(rhs))
//{
// return -1;
//}
//if (rhs.GetConstructorChain().Contains(lhs))
//{
// return 1;
//}
return(0);
}
