Sequence contains no elements ParameterTypes.Last()

[sw1nn4]

ExtensionsForMethodInfo.GetPropertyFromMethod(Type t) is throwing an exception when called on a property getter.

The method name is returned as "IGenericStateSetter`1[Boolean].get_Value", therefore the substring(0,3) does not equal "get", as expected. Since it's a property getter method.GetParameterTypes() returns an empty list, so the call to Last() throws an invalid operation exception.

I'm not trying to intercept the method, but I presume a check is being performed as to whether it should be intercepted or not.
I'm also using a Ninject.MockingKernel to create test mocks for any missing bindings. (The issue happens regardless of which mocking framework is used, I think they all use Castle.Proxies)

I don't believe there's any way to specify not to try intercepting an activation?

Stack trace:

System.Core.dll!System.Linq.Enumerable.Last<System.Type>(System.Collections.Generic.IEnumerable<System.Type> source)
Ninject.Extensions.Interception.dll!Ninject.Extensions.Interception.Infrastructure.Language.ExtensionsForMethodInfo.GetPropertyFromMethod(System.Reflection.MethodInfo method, System.Type implementingType) Line 18	
Ninject.Extensions.Interception.dll!Ninject.Extensions.Interception.Planning.Strategies.InterceptorRegistrationStrategy.Execute(Ninject.Planning.IPlan plan) Line 47	
Ninject.dll!Ninject.Infrastructure.Language.ExtensionsForIEnumerableOfT.Map<Ninject.Planning.Strategies.IPlanningStrategy>(System.Collections.Generic.IEnumerable<Ninject.Planning.Strategies.IPlanningStrategy> series, System.Action<Ninject.Planning.Strategies.IPlanningStrategy> action)	
Ninject.dll!Ninject.Planning.Planner.CreateNewPlan(System.Type type)	
Ninject.dll!Ninject.Planning.Planner.GetPlan(System.Type type)	
Ninject.dll!Ninject.Activation.Context.ResolveInternal(object scope)	
Ninject.dll!Ninject.Activation.Context.Resolve()	
Ninject.dll!Ninject.KernelBase.Resolve(Ninject.Activation.IRequest request, bool handleMissingBindings)	
Ninject.dll!Ninject.Planning.Targets.Target<System.__Canon>.ResolveWithin(Ninject.Activation.IContext parent)	

[szaliszali]

The problem occurs for all explicitly implemented properties In this case, the name does not start with get because it will look like Full.Name.Of.Interface.Type.get_Property.

Location:

Ninject.Extensions.Interception/src/Ninject.Extensions.Interception/Infrastructure/Language/ExtensionsForMethodInfo.cs

Line 48 in a267001

var isGetMethod = method.Name.Substring(0, 3) == "get";

reproduction:

interface IInterface
{
	int Property { get; }
}

class Class : IInterface
{
	int IInterface.Property => -6; // crash
	public int Property => -6; // no crash
}

class Program
{
	static void Main()
	{
		var t = typeof(Class);
		foreach (var method in t.GetMethods(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance))
		{
			Console.WriteLine($"Name: '{method.Name}'");
			Console.WriteLine(method.GetPropertyFromMethod(t));
		}
	}
}

My first guess would be look for the last dot in Name first, and only then check for get prefix. Also, the length<4 condition must be revisited.

Naive attempt to fix the method:

public static PropertyInfo GetPropertyFromMethod(this MethodInfo method, Type implementingType)
{
	if (!method.IsSpecialName)
	{
		return null;
	}

	var fullName = method.Name.AsSpan();
	var lastPeriod = fullName.LastIndexOf('.');
	var interfaceNameWithPeriod = fullName[..(lastPeriod + 1)];
	var name = fullName[(lastPeriod + 1)..];

	if (name.Length < 4)
	{
		return null;
	}
	var isGetMethod = name.StartsWith("get", StringComparison.InvariantCulture);

	var returnType = isGetMethod ? method.ReturnType : method.GetParameterTypes().Last();
	var indexerTypes = isGetMethod ? method.GetParameterTypes() : method.GetParameterTypes().SkipLast(1);

	var propertyName = $"{interfaceNameWithPeriod}{name[4..]}";
	return implementingType.GetProperty(propertyName, DefaultBindingFlags, null, returnType, indexerTypes.ToArray(), null);
}