C#: Add tests for C# 7.3 features.

Author: calumgrant

csharp/extractor/Semmle.Extraction.CSharp/Entities/Expressions/ArrayCreation.cs

@@ -9,7 +9,7 @@ abstract class ArrayCreation<SyntaxNode> : Expression<SyntaxNode> where SyntaxNo
         protected ArrayCreation(ExpressionNodeInfo info) : base(info) { }
     }
 
-    abstract class ExplicitArrayCreation<T> : ArrayCreation<T> where T:ExpressionSyntax
+    abstract class ExplicitArrayCreation<SyntaxNode> : ArrayCreation<SyntaxNode> where SyntaxNode : ExpressionSyntax
     {
         protected ExplicitArrayCreation(ExpressionNodeInfo info) : base(info.SetKind(ExprKind.ARRAY_CREATION)) { }
 

csharp/ql/test/library-tests/csharp7.3/ArrayCreations.expected

@@ -0,0 +1,6 @@
+| csharp73.cs:9:20:9:49 | array creation of type Char* | 0 | csharp73.cs:9:20:9:49 | 2 |
+| csharp73.cs:10:20:10:45 | array creation of type Char* | 0 | csharp73.cs:10:36:10:36 | 1 |
+| csharp73.cs:11:20:11:37 | array creation of type Char[] | 0 | csharp73.cs:11:20:11:37 | 1 |
+| csharp73.cs:12:20:12:38 | array creation of type Char* | 0 | csharp73.cs:12:36:12:37 | 10 |
+| csharp73.cs:13:20:13:31 | array creation of type Char[] | 0 | csharp73.cs:13:29:13:30 | 10 |
+| csharp73.cs:21:23:21:33 | array creation of type Int32[] | 0 | csharp73.cs:21:31:21:32 | 10 |

csharp/ql/test/library-tests/csharp7.3/ArrayCreations.ql

@@ -0,0 +1,4 @@
+import csharp
+
+from ArrayCreation creation, int i
+select creation, i, creation.getLengthArgument(i)

csharp/ql/test/library-tests/csharp7.3/ArrayElements.expected

@@ -0,0 +1,4 @@
+| csharp73.cs:9:20:9:49 | array creation of type Char* | 0 | csharp73.cs:9:40:9:42 | x |
+| csharp73.cs:9:20:9:49 | array creation of type Char* | 1 | csharp73.cs:9:45:9:47 | y |
+| csharp73.cs:10:20:10:45 | array creation of type Char* | 0 | csharp73.cs:10:41:10:43 | x |
+| csharp73.cs:11:20:11:37 | array creation of type Char[] | 0 | csharp73.cs:11:33:11:35 | x |

csharp/ql/test/library-tests/csharp7.3/ArrayElements.ql

@@ -0,0 +1,4 @@
+import csharp
+
+from ArrayCreation array, int i
+select array, i, array.getInitializer().getElement(i)

csharp/ql/test/library-tests/csharp7.3/csharp73.cs

@@ -0,0 +1,52 @@
+// semmle-extractor-options: /langversion:latest
+
+using System;
+
+class StackAllocs
+{
+    unsafe void Fn()
+    {
+        var arr1 = stackalloc char[] { 'x', 'y' };
+        var arr2 = stackalloc char[1] { 'x' };
+        var arr3 = new char[] { 'x' };
+        var arr4 = stackalloc char[10];
+        var arr5 = new char[10];
+    }
+}
+
+class PinnedReference
+{
+    unsafe void F()
+    {
+        Span<int> t = new int[10];
+        // This line should compile and generate a call to t.GetPinnableReference()
+        // fixed (int * p = t)
+        {
+        }
+    }
+}
+
+class UnmanagedConstraint<T> where T : unmanaged
+{
+}
+
+class EnumConstraint<T> where T : System.Enum
+{
+}
+
+class DelegateConstraint<T> where T : System.Delegate
+{
+}
+
+class ExpressionVariables
+{
+    ExpressionVariables(out int x)
+    {
+        x = 5;
+    }
+
+    public ExpressionVariables() : this(out int x)
+    {
+        Console.WriteLine($"x is {x}");
+    }
+}