C#: Add more testcases and update expected output.

Author: michaelnebel

csharp/ql/test/library-tests/spans/Slice.cs

@@ -2,18 +2,20 @@
 
 public class C
 {
-    public void M(int a)
+    public void M(int a, int b)
     {
         var s = "hello world";
         var sub1 = s[1..a];
         var sub2 = s[..2];
         var sub3 = s[3..];
         var sub4 = s[..^4];
+        var sub5 = s[a..^b];
 
         Span<int> sp = null;
         var slice1 = sp[5..a];
         var slice2 = sp[..6];
         var slice3 = sp[7..];
         var slice4 = sp[..^8];
+        var slice5 = sp[a..^b];
     }
 }

csharp/ql/test/library-tests/spans/slice.expected

@@ -7,16 +7,22 @@ methodCalls
 | Slice.cs:10:20:10:25 | call to method Substring | Substring(int, int) | 1 | access to property Length - 3 |
 | Slice.cs:11:20:11:26 | call to method Substring | Substring(int, int) | 0 | 0 |
 | Slice.cs:11:20:11:26 | call to method Substring | Substring(int, int) | 1 | access to property Length - 4 |
-| Slice.cs:14:22:14:29 | call to method Slice | Slice(int, int) | 0 | 5 |
-| Slice.cs:14:22:14:29 | call to method Slice | Slice(int, int) | 1 | access to parameter a - 5 |
-| Slice.cs:15:22:15:28 | call to method Slice | Slice(int, int) | 0 | 0 |
-| Slice.cs:15:22:15:28 | call to method Slice | Slice(int, int) | 1 | 6 |
-| Slice.cs:16:22:16:28 | call to method Slice | Slice(int, int) | 0 | 7 |
-| Slice.cs:16:22:16:28 | call to method Slice | Slice(int, int) | 1 | access to property Length - 7 |
-| Slice.cs:17:22:17:29 | call to method Slice | Slice(int, int) | 0 | 0 |
-| Slice.cs:17:22:17:29 | call to method Slice | Slice(int, int) | 1 | access to property Length - 8 |
+| Slice.cs:12:20:12:27 | call to method Substring | Substring(int, int) | 0 | access to parameter a |
+| Slice.cs:12:20:12:27 | call to method Substring | Substring(int, int) | 1 | access to property Length - access to parameter b - access to parameter a |
+| Slice.cs:15:22:15:29 | call to method Slice | Slice(int, int) | 0 | 5 |
+| Slice.cs:15:22:15:29 | call to method Slice | Slice(int, int) | 1 | access to parameter a - 5 |
+| Slice.cs:16:22:16:28 | call to method Slice | Slice(int, int) | 0 | 0 |
+| Slice.cs:16:22:16:28 | call to method Slice | Slice(int, int) | 1 | 6 |
+| Slice.cs:17:22:17:28 | call to method Slice | Slice(int, int) | 0 | 7 |
+| Slice.cs:17:22:17:28 | call to method Slice | Slice(int, int) | 1 | access to property Length - 7 |
+| Slice.cs:18:22:18:29 | call to method Slice | Slice(int, int) | 0 | 0 |
+| Slice.cs:18:22:18:29 | call to method Slice | Slice(int, int) | 1 | access to property Length - 8 |
+| Slice.cs:19:22:19:30 | call to method Slice | Slice(int, int) | 0 | access to parameter a |
+| Slice.cs:19:22:19:30 | call to method Slice | Slice(int, int) | 1 | access to property Length - access to parameter b - access to parameter a |
 propertyCalls
 | Slice.cs:10:20:10:25 | access to property Length | Slice.cs:10:20:10:20 | access to local variable s |
 | Slice.cs:11:20:11:26 | access to property Length | Slice.cs:11:20:11:20 | access to local variable s |
-| Slice.cs:16:22:16:28 | access to property Length | Slice.cs:16:22:16:23 | access to local variable sp |
-| Slice.cs:17:22:17:29 | access to property Length | Slice.cs:17:22:17:23 | access to local variable sp |
+| Slice.cs:12:20:12:27 | access to property Length | Slice.cs:12:20:12:20 | access to local variable s |
+| Slice.cs:17:22:17:28 | access to property Length | Slice.cs:17:22:17:23 | access to local variable sp |
+| Slice.cs:18:22:18:29 | access to property Length | Slice.cs:18:22:18:23 | access to local variable sp |
+| Slice.cs:19:22:19:30 | access to property Length | Slice.cs:19:22:19:23 | access to local variable sp |

csharp/ql/test/library-tests/spans/slice.ql

@@ -3,7 +3,7 @@ import csharp
 private string printExpr(Expr e) {
   e =
     any(SubExpr sub |
-      result = sub.getLeftOperand().toString() + " - " + sub.getRightOperand().toString()
+      result = printExpr(sub.getLeftOperand()) + " - " + printExpr(sub.getRightOperand())
     )
   or
   not e instanceof SubExpr and