Always cast RHS of bitshift operators to int

This is to fix: #611

Always casting to int will work because C# only allows ints as the RHS parameter for bitshifts: https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/language-specification/expressions#1211-shift-operators

Author: Exanite

sources/ClangSharp.PInvokeGenerator/PInvokeGenerator.VisitStmt.cs

@@ -41,7 +41,22 @@ private void VisitBinaryOperator(BinaryOperator binaryOperator)
         outputBuilder.Write(' ');
         outputBuilder.Write(binaryOperator.OpcodeStr);
         outputBuilder.Write(' ');
-        Visit(binaryOperator.RHS);
+
+        if (binaryOperator.IsShiftOp || binaryOperator.IsShiftAssignOp)
+        {
+            // RHS of shift operation in C# must be an int
+            outputBuilder.Write("(int)");
+            outputBuilder.Write('(');
+
+            Visit(binaryOperator.RHS);
+
+            outputBuilder.Write(')');
+        }
+        else
+        {
+            Visit(binaryOperator.RHS);
+        }
+
         StopCSharpCode();
     }
 

tests/ClangSharp.PInvokeGenerator.UnitTests/CTest.cs

@@ -283,14 +283,18 @@ public static partial class Methods
     [Test]
     public Task UnsignedIntBitshiftTest()
     {
-        var inputContents = @"#define BITSHIFT 1 << 1U";
+        var inputContents = @"#define LEFT 1 << 1U
+#define RIGHT 1 >> 1U";
 
         var expectedOutputContents = @"namespace ClangSharp.Test
 {
     public static partial class Methods
     {
-        [NativeTypeName(""#define BITSHIFT 1 << 1U"")]
-        public const int BITSHIFT = 1 << (int)(1U);
+        [NativeTypeName(""#define LEFT 1 << 1U"")]
+        public const int LEFT = 1 << (int)(1U);
+
+        [NativeTypeName(""#define RIGHT 1 >> 1U"")]
+        public const int RIGHT = 1 >> (int)(1U);
     }
 }
 ";