Fix nested list types in Typemaker

DMCompiler/DM/DMValueType.cs

@@ -95,7 +95,7 @@ internal bool MatchesType(DMCompiler compiler, DMComplexValueType type) {
                 return true;
             }
             var theirPath = type.AsPath();
-            if (theirPath is not null) {
+            if (type.ListValueTypes is null && theirPath is not null) {
                 compiler.DMObjectTree.TryGetDMObject(theirPath!.Value, out var theirObject);
                 if (theirObject?.IsSubtypeOf(TypePath!.Value) is true) {
                     return true;
@@ -120,7 +120,8 @@ internal bool MatchesType(DMCompiler compiler, DMComplexValueType type) {
                 return ourObject?.IsSubtypeOf(type.TypePath!.Value) ?? false;
             }
             // If ListValueTypes is non-null, we do more advanced checks.
-            if (TypePath!.Value == DreamPath.List && ListValueTypes is not null && type.ListValueTypes is not null) {
+            // The other type's must also be non-null, because we consider empty lists as matching.
+            if (ListValueTypes is not null && type.ListValueTypes is not null) {
                 // Have to do an actual match check here. This can get expensive, but thankfully it's pretty rare.
                 if (!ListValueTypes.NestedListKeyType.MatchesType(compiler, type.ListValueTypes!.NestedListKeyType))
                     return false;