Merge pull request github#6579 from tamasvajk/fix/cil-type-args

C#: Fix completely broken type argument extraction in NoMetadataHandleType

Author: tamasvajk

csharp/extractor/Semmle.Extraction.CIL/Entities/NoMetadataHandleType.FullyQualifiedNameParser.cs

@@ -53,7 +53,7 @@ private void ExtractTypeArguments(ref string name, int lastBracketIndex, out str
 
                 // "T3,[T4, Assembly1, Version=...],T5,T6"
                 string typeArgs;
-                (name, _, typeArgs, _) = name.Split(firstBracketIndex, firstBracketIndex + 1, lastBracketIndex - firstBracketIndex - 1);
+                (name, _, typeArgs, _) = name.Split(firstBracketIndex, firstBracketIndex + 1, lastBracketIndex);
 
                 var thisTypeArgCount = GenericsHelper.GetGenericTypeParameterCount(name);
                 if (thisTypeArgCount == 0)

csharp/extractor/Semmle.Util/StringExtensions.cs

@@ -20,7 +20,7 @@ public static (string, string, string) Split(this string self, int index0, int i
         public static (string, string, string, string) Split(this string self, int index0, int index1, int index2)
         {
             var split = self.Split(new[] { index0, index1, index2 });
-            return (split[0], split[1], split[2], split[4]);
+            return (split[0], split[1], split[2], split[3]);
         }
 
         private static List<string> Split(this string self, params int[] indices)