C#: Add testcase for CIL generic attribute extraction.

csharp/ql/test/library-tests/csharp11/cil/Assembly.cs_

@@ -0,0 +1,16 @@
+using System;
+
+namespace Assembly
+{
+    public class MyAssemblyGeneric1Attribute<T> : Attribute { }
+    public class MyAssemblyGeneric2Attribute<T, U> : Attribute { }
+
+    public class TestAssemblyGenericAttribute
+    {
+        [MyAssemblyGeneric1Attribute<object>()]
+        public void M1() { }
+
+        [MyAssemblyGeneric2<int, string>()]
+        public void M2() { }
+    }
+}

csharp/ql/test/library-tests/csharp11/cil/class1.cs

@@ -0,0 +1,7 @@
+using System;
+using Assembly;
+
+public class Class1
+{
+    public static void Main(string[] args) { }
+}

csharp/ql/test/library-tests/csharp11/cil/genericAttribute.expected

@@ -0,0 +1,2 @@
+| assembly.dll:0:0:0:0 | [MyAssemblyGeneric1Attribute<Object>(...)] | MyAssemblyGeneric1Attribute<Object> | 1 | (Object) |
+| assembly.dll:0:0:0:0 | [MyAssemblyGeneric2Attribute<Int32,String>(...)] | MyAssemblyGeneric2Attribute<Int32,String> | 2 | (Int32,String) |

csharp/ql/test/library-tests/csharp11/cil/genericAttribute.ql

@@ -0,0 +1,9 @@
+import semmle.code.cil.CIL
+
+private string getTypeArguments(GenericAttribute a) {
+  result = "(" + concat(Type t | t = a.getATypeArgument() | t.getName(), ",") + ")"
+}
+
+from GenericAttribute a
+where a.getFile().getStem() = "assembly"
+select a, a.getType().getName(), a.getNumberOfTypeArguments(), getTypeArguments(a)

csharp/ql/test/library-tests/csharp11/cil/options

@@ -0,0 +1 @@
+semmle-extractor-options: --cil