Minor improvements (#1793)

* CppSharp.Generators.Options: added pre/post TranslationUnitPass callback

* CppSharp.Generators.Passes.Pass: added TranslationUnitPassGeneratorDependent

src/Generator/BindingContext.cs

@@ -2,6 +2,7 @@ using CppSharp.AST;
 using CppSharp.Passes;
 using CppSharp.Types;
 using CppSharp.Parser;
+using System.Collections.Generic;
 
 namespace CppSharp.Generators
 {
@@ -36,14 +37,21 @@ namespace CppSharp.Generators
 
         public void RunPasses()
         {
+            Dictionary<System.Type, int> passesByType = new Dictionary<System.Type, int>();
+            int index = 0;
             TranslationUnitPasses.RunPasses(pass =>
                 {
+                    int count = passesByType.GetValueOrDefault(pass.GetType(), 0);
                     Diagnostics.Debug("Pass '{0}'", pass);
 
                     Diagnostics.PushIndent();
+                    Options.TranslationUnitPassPreCallBack?.Invoke(pass, index, count);
                     pass.Context = this;
                     pass.VisitASTContext(ASTContext);
+                    Options.TranslationUnitPassPostCallBack?.Invoke(pass, index, count);
                     Diagnostics.PopIndent();
+                    passesByType[pass.GetType()] = count + 1;
+                    index += 1;
                 });
         }
     }

src/Generator/Options.cs

@@ -5,6 +5,7 @@ using System.Linq;
 using System.Text;
 using CppSharp.AST;
 using CppSharp.Generators;
+using CppSharp.Passes;
 
 namespace CppSharp
 {
@@ -254,6 +255,12 @@ namespace CppSharp
         /// </summary>
         public bool GenerateExternalDataFields { get; set; } = false;
 
+        public delegate void TranslationUnitPassCallBack(TranslationUnitPass pass, int index, int count);
+
+        public TranslationUnitPassCallBack TranslationUnitPassPreCallBack { get; set; }
+
+        public TranslationUnitPassCallBack TranslationUnitPassPostCallBack { get; set; }
+
         #endregion
     }
 

src/Generator/Passes/Pass.cs

@@ -51,6 +51,16 @@ namespace CppSharp.Passes
         }
     }
 
+    public class TranslationUnitPassGeneratorDependent : TranslationUnitPass
+    {
+        public Generator Generator { get; }
+
+        public TranslationUnitPassGeneratorDependent(Generator generator)
+        {
+            Generator = generator;
+        }
+    }
+
     /// <summary>
     /// Used to modify generated output.
     /// </summary>