QL code and tests for C#/C++/JavaScript.

csharp/ql/src/Useless code/DefaultToStringGood.cs

@@ -0,0 +1,25 @@
+using System;
+
+class Good
+{
+    static void Main(string[] args)
+    {
+        var p = new Person("Eric Arthur Blair");
+        Console.WriteLine("p: " + p);
+
+        var ints = new int[] { 1, 2, 3 };
+        Console.WriteLine("ints: " + string.Join(", ", ints));
+    }
+
+    class Person
+    {
+        private string Name;
+
+        public Person(string name)
+        {
+            this.Name = name;
+        }
+
+        public override string ToString() => Name;
+    }
+}