C#: Add some testcases for generics.

Author: michaelnebel

csharp/ql/test/utils/model-generator/CaptureSummaryModels.expected

@@ -17,6 +17,13 @@
 | Summaries;CollectionFlow;false;ReturnArrayElement;(System.Int32[]);Argument[0].Element;ReturnValue;taint |
 | Summaries;CollectionFlow;false;ReturnFieldInAList;();Argument[Qualifier];ReturnValue;taint |
 | Summaries;CollectionFlow;false;ReturnListElement;(System.Collections.Generic.List<System.Object>);Argument[0].Element;ReturnValue;taint |
+| Summaries;GenericFlow<>;false;AddFieldToGenericList;(System.Collections.Generic.List<T>);Argument[Qualifier];Argument[0].Element;taint |
+| Summaries;GenericFlow<>;false;AddToGenericList<>;(System.Collections.Generic.List<S>,S);Argument[1];Argument[0].Element;taint |
+| Summaries;GenericFlow<>;false;ReturnFieldInGenericList;();Argument[Qualifier];ReturnValue;taint |
+| Summaries;GenericFlow<>;false;ReturnGenericElement<>;(System.Collections.Generic.List<S>);Argument[0].Element;ReturnValue;taint |
+| Summaries;GenericFlow<>;false;ReturnGenericField;();Argument[Qualifier];ReturnValue;taint |
+| Summaries;GenericFlow<>;false;ReturnGenericParam<>;(S);Argument[0];ReturnValue;taint |
+| Summaries;GenericFlow<>;false;SetGenericField;(T);Argument[0];Argument[Qualifier];taint |
 | Summaries;IEnumerableFlow;false;ReturnFieldInIEnumerable;();Argument[Qualifier];ReturnValue;taint |
 | Summaries;IEnumerableFlow;false;ReturnIEnumerable;(System.Collections.Generic.IEnumerable<System.String>);Argument[0].Element;ReturnValue;taint |
 | Summaries;IEnumerableFlow;false;ReturnIEnumerableElement;(System.Collections.Generic.IEnumerable<System.Object>);Argument[0].Element;ReturnValue;taint |

csharp/ql/test/utils/model-generator/Summaries.cs

@@ -122,4 +122,44 @@ public void AssignFieldToBulkArray(char[] input)
     {
         input[0] = tainted;
     }
-}
+}
+
+public class GenericFlow<T>
+{
+    private T tainted;
+
+    public void SetGenericField(T t)
+    {
+        tainted = t;
+    }
+
+    public T ReturnGenericField()
+    {
+        return tainted;
+    }
+
+    public void AddFieldToGenericList(List<T> input)
+    {
+        input.Add(tainted);
+    }
+
+    public List<T> ReturnFieldInGenericList()
+    {
+        return new List<T> { tainted };
+    }
+
+    public S ReturnGenericParam<S>(S input)
+    {
+        return input;
+    }
+
+    public S ReturnGenericElement<S>(List<S> input)
+    {
+        return input[0];
+    }
+
+    public void AddToGenericList<S>(List<S> input, S data)
+    {
+        input.Add(data);
+    }
+}