Add Preprocessing Wrappers (#84)

* Add Preprocessing Wrappers

* Change structure layout.

sources/ClangSharp/Cursors/Cursor.cs

@@ -80,6 +80,10 @@ internal static Cursor Create(CXCursor handle)
             {
                 result = Attr.Create(handle);
             }
+            else if (handle.IsPreprocessing)
+            {
+                result = PreprocessedEntity.Create(handle);
+            }
             else
             {
                 Debug.WriteLine($"Unhandled cursor kind: {handle.KindSpelling}.");

sources/ClangSharp/Cursors/Preprocessings/InclusionDirective.cs

@@ -0,0 +1,11 @@
+using ClangSharp.Interop;
+
+namespace ClangSharp
+{
+    public sealed class InclusionDirective : PreprocessingDirective
+    {
+        internal InclusionDirective(CXCursor handle) : base(handle, CXCursorKind.CXCursor_InclusionDirective)
+        {
+        }
+    }
+}

sources/ClangSharp/Cursors/Preprocessings/MacroDefinition.cs

@@ -0,0 +1,15 @@
+using ClangSharp.Interop;
+
+namespace ClangSharp
+{
+    public sealed class MacroDefinitionRecord : PreprocessingDirective
+    {
+        internal MacroDefinitionRecord(CXCursor handle) : base(handle, CXCursorKind.CXCursor_MacroDefinition)
+        {
+        }
+
+        public bool IsMacroFunctionLike => Handle.IsMacroFunctionLike;
+
+        public bool IsMacroBuiltIn => Handle.IsMacroBuiltIn;
+    }
+}

sources/ClangSharp/Cursors/Preprocessings/MacroExpansion.cs

@@ -0,0 +1,13 @@
+using ClangSharp.Interop;
+
+namespace ClangSharp
+{
+    public sealed class MacroExpansion : PreprocessedEntity
+    {
+        internal MacroExpansion(CXCursor handle) : base(handle, CXCursorKind.CXCursor_MacroExpansion)
+        {
+        }
+
+        public bool IsMacroBuiltIn => Handle.IsMacroBuiltIn;
+    }
+}

sources/ClangSharp/Cursors/Preprocessings/PreprocessedEntity.cs

@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using ClangSharp.Interop;
+
+namespace ClangSharp
+{
+    public class PreprocessedEntity : Cursor
+    {
+        private protected PreprocessedEntity(CXCursor handle, CXCursorKind expectedKind) : base(handle, expectedKind)
+        {
+        }
+
+        internal static new PreprocessedEntity Create(CXCursor handle)
+        {
+            PreprocessedEntity result;
+
+            switch (handle.Kind)
+            {
+                case CXCursorKind.CXCursor_MacroDefinition:
+                {
+                    result = new MacroDefinitionRecord(handle);
+                    break;
+                }
+
+                case CXCursorKind.CXCursor_MacroExpansion:
+                {
+                    result = new MacroExpansion(handle);
+                    break;
+                }
+
+                case CXCursorKind.CXCursor_PreprocessingDirective:
+                {
+                    result = new PreprocessingDirective(handle);
+                    break;
+                }
+
+                case CXCursorKind.CXCursor_InclusionDirective:
+                {
+                    result = new InclusionDirective(handle);
+                    break;
+                }
+
+                default:
+                {
+                    Debug.WriteLine($"Unhandled preprocessing kind: {handle.KindSpelling}.");
+                    Debugger.Break();
+
+                    result = new PreprocessedEntity(handle, handle.Kind);
+                    break;
+                }
+            }
+
+            return result;
+        }
+    }
+}

sources/ClangSharp/Cursors/Preprocessings/PreprocessingDirective.cs

@@ -0,0 +1,14 @@
+using ClangSharp.Interop;
+
+namespace ClangSharp
+{
+    public class PreprocessingDirective : PreprocessedEntity
+    {
+        internal PreprocessingDirective(CXCursor handle) : this(handle, CXCursorKind.CXCursor_PreprocessingDirective)
+        {
+        }
+        private protected PreprocessingDirective(CXCursor handle, CXCursorKind expectedKind) : base(handle, expectedKind)
+        {
+        }
+    }
+}