fixed OnBeforeGeneration and OnBeforeBarrelGeneration logic

Author: jburzynski

src/TypeGen/TypeGen.Core/Generator/Generator.cs

@@ -145,11 +145,13 @@ public IEnumerable<string> Generate(IEnumerable<GenerationSpec> generationSpecs)
 
             // generate types
 
+            foreach (GenerationSpec generationSpec in generationSpecs)
+                generationSpec.OnBeforeGeneration(new OnBeforeGenerationArgs(Options));
+            
             foreach (GenerationSpec generationSpec in generationSpecs)
             {
                 _metadataReaderFactory.GenerationSpec = generationSpec;
-                generationSpec.OnBeforeGeneration(new OnBeforeGenerationArgs(Options));
-
+                
                 foreach (KeyValuePair<Type, TypeSpec> kvp in generationSpec.TypeSpecs)
                     files.AddRange(GenerateMarkedType(kvp.Key));
             }
@@ -158,12 +160,12 @@ public IEnumerable<string> Generate(IEnumerable<GenerationSpec> generationSpecs)
 
             // generate barrels
 
-            if (Options.CreateIndexFile)
-                files.AddRange(GenerateIndexFile(files));
-            
             foreach (GenerationSpec generationSpec in generationSpecs)
                 generationSpec.OnBeforeBarrelGeneration(new OnBeforeBarrelGenerationArgs(Options, files.ToList()));
 
+            if (Options.CreateIndexFile)
+                files.AddRange(GenerateIndexFile(files));
+            
             foreach (GenerationSpec generationSpec in generationSpecs)
                 foreach (BarrelSpec barrelSpec in generationSpec.BarrelSpecs)
                     files.AddRange(GenerateBarrel(barrelSpec));