diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -31,6 +31,7 @@ details about the cause of the failure
-    Fix non-delegate types incorrectly appearing as callable.
-    Indexers can now be used with interface objects
-    Fixed a bug where indexers could not be used if they were inherited

## [2.5.0][] - 2020-06-14


diff --git a/src/runtime/slots/mp_length.cs b/src/runtime/slots/mp_length.cs
@@ -26,7 +26,7 @@ public static MethodInfo Method
            }
        }

-        public static bool CanAssgin(Type clrType)
        {
            if (typeof(ICollection).IsAssignableFrom(clrType))
            {
@@ -36,6 +36,10 @@ public static bool CanAssgin(Type clrType)
            {
                return true;
            }
            return false;
        }


diff --git a/src/runtime/typemanager.cs b/src/runtime/typemanager.cs
@@ -225,7 +225,7 @@ internal static IntPtr CreateType(ManagedType impl, Type clrType)
            InitializeSlots(type, impl.GetType(), slotsHolder);

            if (Marshal.ReadIntPtr(type, TypeOffset.mp_length) == IntPtr.Zero
-                && mp_length_slot.CanAssgin(clrType))
            {
                InitializeSlot(type, TypeOffset.mp_length, mp_length_slot.Method, slotsHolder);
            }

diff --git a/src/tests/test_mp_length.py b/src/tests/test_mp_length.py
@@ -47,3 +47,17 @@ def test_custom_generic_collection_explicit___len__():
    s.Add(1)
    s.Add(10)
    assert len(s) == 2
-Original file line number
+Diff line change
@@ Expand Up / @@ -26,7 +26,7 @@ public static MethodInfo Method @@
                 }
             }
-            public static bool CanAssgin(Type clrType)
             {
                 if (typeof(ICollection).IsAssignableFrom(clrType))
                 {
@@ Expand All / @@ -36,6 +36,10 @@ public static bool CanAssgin(Type clrType) @@
                 {
                     return true;
                 }
                 return false;
             }
@@ Expand Down @@
Original file line number	Diff line number	Diff line change
		@@ -47,3 +47,17 @@ def test_custom_generic_collection_explicit___len__():
		s.Add(1)
		s.Add(10)
		assert len(s) == 2