BUG: getting the element type of enumerable types

[bcristianParticipant]

Hello
There are several cases where the code tries to determine the type of elements in a enumerable type.
However, it only checks if the type is an array, or it tries to get the first generic argument. Sometimes it doesn’t even check for the possibility of an array.
This is not sufficient, as all the following are valid enumerable types. Also, the check should be done against the lowest denominator, Enumerable<T>.

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int[] asd; List<int> asd;   class Asd : IList<int> {} Asd asd;   class A<T> : IList<T> {} class B : A<int> {} B asd;   // Don't stop at the first generic type! class A<T> : IList<T> {} class B<U> : A<int> {} B<QWE> asd;   // and sometimes the parameters can be non-generic too List asd;   class Asd : IList {} Asd asd;

I’ve added the following in ReflectionTools.cs (for lack of a better idea of where to put it)

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public static Type GetEnumerableElementType(Type enumType)         {             if (enumType == null)                 throw new ArgumentException("Null type argument");             if (!typeof(IEnumerable).IsAssignableFrom(enumType))                 throw new ArgumentException("Type is not an IList: " + enumType.FullName);               if (enumType.RTIsArray())                 return enumType.GetElementType();               var ii = enumType.FindInterfaces((i, c) =>             {                 if (!i.RTIsGenericType())                     return false;                 var genType = i.GetGenericTypeDefinition();                 if (genType != typeof(IEnumerable<>))                     return false;                 return true;             }, null);               if (ii != null && ii.Length > 0)                 return ii[0].RTGetGenericArguments()[0];             else                 return typeof(System.Object);         }

and used it in all the places I could find that used the incomplete method:

EditorUtils_GUIEditors.cs:52
UserTypePrefs.cs:181
Iterator.cs:111

NOTE: the same thing should be done for dictionaries.

[GavalakisKeymaster]

Thanks a lot for pointing this out as well as for the code.
I will run through the source and see where it needs to be fixed.

Thanks again.

[Author]

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