Fixed a memory leak in the code generators.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

src/Generator.Tests/Passes/TestPasses.cs

@@ -70,7 +70,7 @@ namespace CppSharp.Generator.Tests.Passes
         [Test]
         public void TestCaseRenamePass()
         {
-            Type.TypePrinterDelegate += type => type.Visit(new CSharpTypePrinter(Driver)).Type;
+            CppSharp.AST.Type.TypePrinterDelegate += TypePrinterDelegate;
 
             var c = AstContext.Class("TestRename");
 
@@ -82,6 +82,8 @@ namespace CppSharp.Generator.Tests.Passes
 
             Assert.That(method.Name, Is.EqualTo("LowerCaseMethod"));
             Assert.That(field.Name, Is.EqualTo("LowerCaseField"));
+
+            CppSharp.AST.Type.TypePrinterDelegate -= TypePrinterDelegate;
         }
 
         [Test]
@@ -202,5 +204,10 @@ namespace CppSharp.Generator.Tests.Passes
             passBuilder.RunPasses(pass => pass.VisitLibrary(AstContext));
             Assert.AreEqual(method.Access , AccessSpecifier.Internal);
         }
+
+        private string TypePrinterDelegate(CppSharp.AST.Type type)
+        {
+            return type.Visit(new CSharpTypePrinter(Driver)).Type;
+        }
     }
 }

src/Generator/Driver.cs

@@ -496,6 +496,8 @@ namespace CppSharp
                 if (driver.Options.IsCSharpGenerator && driver.Options.CompileCode)
                     driver.CompileCode();
             }
+
+            driver.Generator.Dispose();
         }
     }
 }

src/Generator/Generator.cs

@@ -33,13 +33,14 @@ namespace CppSharp.Generators
     /// <summary>
     /// Generators are the base class for each language backend.
     /// </summary>
-    public abstract class Generator
+    public abstract class Generator : IDisposable
     {
         public Driver Driver { get; private set; }
 
         protected Generator(Driver driver)
         {
             Driver = driver;
+            CppSharp.AST.Type.TypePrinterDelegate += TypePrinterDelegate;
         }
 
         /// <summary>
@@ -119,9 +120,16 @@ namespace CppSharp.Generators
         /// </summary>
         public abstract List<Template> Generate(IEnumerable<TranslationUnit> units);
 
+        protected abstract string TypePrinterDelegate(CppSharp.AST.Type type);
+
         public static string GeneratedIdentifier(string id)
         {
             return "__" + id;
         }
+
+        public void Dispose()
+        {
+            CppSharp.AST.Type.TypePrinterDelegate -= TypePrinterDelegate;
+        }
     }
 }

src/Generator/Generators/CLI/CLIGenerator.cs

@@ -14,7 +14,6 @@ namespace CppSharp.Generators.CLI
         public CLIGenerator(Driver driver) : base(driver)
         {
             typePrinter = new CLITypePrinter(driver);
-            Type.TypePrinterDelegate += type => type.Visit(typePrinter);
         }
 
         public override List<Template> Generate(IEnumerable<TranslationUnit> units)
@@ -45,5 +44,10 @@ namespace CppSharp.Generators.CLI
                 return false;
             return @class.IsRefType && (!@class.HasBase || !@class.HasRefBase());
         }
+
+        protected override string TypePrinterDelegate(Type type)
+        {
+            return type.Visit(typePrinter);
+        }
     }
 }

src/Generator/Generators/CSharp/CSharpGenerator.cs

@@ -13,7 +13,6 @@ namespace CppSharp.Generators.CSharp
         {
             typePrinter = new CSharpTypePrinter(driver);
             expressionPrinter = new CSharpExpressionPrinter(typePrinter);
-            CppSharp.AST.Type.TypePrinterDelegate += type => type.Visit(typePrinter).Type;
         }
 
         public override List<Template> Generate(IEnumerable<TranslationUnit> units)
@@ -37,5 +36,10 @@ namespace CppSharp.Generators.CSharp
 
             return true;
         }
+
+        protected override string TypePrinterDelegate(Type type)
+        {
+            return type.Visit(typePrinter).Type;
+        }
     }
 }