Replace uses of DiagnosticBag with IErrorListener where feasible in t…

…he build process

src/AsmResolver.DotNet/Builder/DotNetDirectoryFactory.cs

@@ -73,13 +73,13 @@ public StrongNamePrivateKey? StrongNamePrivateKey
         public virtual DotNetDirectoryBuildResult CreateDotNetDirectory(
             ModuleDefinition module,
             INativeSymbolsProvider symbolsProvider,
-            DiagnosticBag diagnosticBag)
+            IErrorListener errorListener)
         {
             // Find all members in the module.
             var discoveryResult = DiscoverMemberDefinitionsInModule(module);
 
             // Creat new .NET dir buffer.
-            var buffer = CreateDotNetDirectoryBuffer(module, symbolsProvider, diagnosticBag);
+            var buffer = CreateDotNetDirectoryBuffer(module, symbolsProvider, errorListener);
             buffer.DefineModule(module);
 
             // When specified, import existing AssemblyRef, ModuleRef, TypeRef and MemberRef prior to adding any other
@@ -148,10 +148,10 @@ private MemberDiscoveryResult DiscoverMemberDefinitionsInModule(ModuleDefinition
         private DotNetDirectoryBuffer CreateDotNetDirectoryBuffer(
             ModuleDefinition module,
             INativeSymbolsProvider symbolsProvider,
-            DiagnosticBag diagnosticBag)
+            IErrorListener errorListener)
         {
             var metadataBuffer = CreateMetadataBuffer(module);
-            return new DotNetDirectoryBuffer(module, MethodBodySerializer, symbolsProvider, metadataBuffer, diagnosticBag);
+            return new DotNetDirectoryBuffer(module, MethodBodySerializer, symbolsProvider, metadataBuffer, errorListener);
         }
 
         private IMetadataBuffer CreateMetadataBuffer(ModuleDefinition module)

src/AsmResolver.DotNet/Builder/IDotNetDirectoryFactory.cs

@@ -13,9 +13,9 @@ public interface IDotNetDirectoryFactory
         /// </summary>
         /// <param name="module">The module to serialize to a .NET data directory.</param>
         /// <param name="symbolsProvider">The object responsible for providing references to native symbols.</param>
-        /// <param name="diagnosticBag">The bag that is used to collect all diagnostic information during the building process. </param>
+        /// <param name="errorListener">The listener that is used to collect all diagnostic information during the building process. </param>
         /// <returns>The serialized data directory.</returns>
         /// <exception cref="MetadataBuilderException">Occurs when the metadata builder encounters an error.</exception>
-        DotNetDirectoryBuildResult CreateDotNetDirectory(ModuleDefinition module, INativeSymbolsProvider symbolsProvider, DiagnosticBag diagnosticBag);
+        DotNetDirectoryBuildResult CreateDotNetDirectory(ModuleDefinition module, INativeSymbolsProvider symbolsProvider, IErrorListener errorListener);
     }
-}
+}

src/AsmResolver.DotNet/Builder/ManagedPEImageBuilder.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using AsmResolver.DotNet.Code.Native;
 using AsmResolver.PE;
@@ -74,7 +74,7 @@ public PEImageBuildResult CreateImage(ModuleDefinition module)
                 var result = DotNetDirectoryFactory.CreateDotNetDirectory(
                     module,
                     symbolProvider,
-                    context.DiagnosticBag);
+                    context.ErrorListener);
                 image.DotNetDirectory = result.Directory;
                 tokenMapping = result.TokenMapping;
 
@@ -108,12 +108,12 @@ public PEImageBuildResult CreateImage(ModuleDefinition module)
             }
             catch (Exception ex)
             {
-                context.DiagnosticBag.RegisterException(ex);
-                context.DiagnosticBag.MarkAsFatal();
+                context.ErrorListener.RegisterException(ex);
+                context.ErrorListener.MarkAsFatal();
             }
 
             tokenMapping ??= new TokenMapping();
-            return new PEImageBuildResult(image, context.DiagnosticBag, tokenMapping);
+            return new PEImageBuildResult(image, context.ErrorListener, tokenMapping);
         }
     }
 }

src/AsmResolver.DotNet/Builder/PEImageBuildContext.cs

@@ -12,24 +12,24 @@ public class PEImageBuildContext
         /// </summary>
         public PEImageBuildContext()
         {
-            DiagnosticBag = new DiagnosticBag();
+            ErrorListener = new DiagnosticBag();
         }
 
         /// <summary>
         /// Creates a new build context.
         /// </summary>
         /// <param name="diagnosticBag">The diagnostic bag to use.</param>
-        public PEImageBuildContext(DiagnosticBag diagnosticBag)
+        public PEImageBuildContext(IErrorListener diagnosticBag)
         {
-            DiagnosticBag = diagnosticBag ?? throw new ArgumentNullException(nameof(diagnosticBag));
+            ErrorListener = diagnosticBag ?? throw new ArgumentNullException(nameof(diagnosticBag));
         }
 
         /// <summary>
-        /// Gets the bag that collects all diagnostic information during the building process. 
+        /// Gets the error listener that collects all diagnostic information during the building process.
         /// </summary>
-        public DiagnosticBag DiagnosticBag
+        public IErrorListener ErrorListener
         {
             get;
         } 
     }
-}
+}

src/AsmResolver.DotNet/Builder/PEImageBuildResult.cs

@@ -13,12 +13,12 @@ public class PEImageBuildResult
         /// Creates a new instance of the <see cref="PEImageBuildResult"/> class.
         /// </summary>
         /// <param name="image">The constructed image, or <c>null</c> if the construction failed.</param>
-        /// <param name="diagnosticBag">The diagnostics that were collected during the construction of the image.</param>
+        /// <param name="errorListener">The diagnostics that were collected during the construction of the image.</param>
         /// <param name="tokenMapping">An object that maps metadata members to their newly assigned tokens.</param>
-        public PEImageBuildResult(IPEImage? image, DiagnosticBag diagnosticBag, ITokenMapping tokenMapping)
+        public PEImageBuildResult(IPEImage? image, IErrorListener errorListener, ITokenMapping tokenMapping)
         {
             ConstructedImage = image;
-            DiagnosticBag = diagnosticBag ?? throw new ArgumentNullException(nameof(diagnosticBag));
+            ErrorListener = errorListener ?? throw new ArgumentNullException(nameof(errorListener));
             TokenMapping = tokenMapping ?? throw new ArgumentNullException(nameof(tokenMapping));
         }
 
@@ -34,12 +34,12 @@ public IPEImage? ConstructedImage
         /// Gets a value indicating whether the image was constructed successfully or not.
         /// </summary>
         [MemberNotNullWhen(false, nameof(ConstructedImage))]
-        public bool HasFailed => DiagnosticBag.IsFatal;
+        public bool HasFailed => ConstructedImage is null;
 
         /// <summary>
         /// Gets the bag containing the diagnostics that were collected during the construction of the image.
         /// </summary>
-        public DiagnosticBag DiagnosticBag
+        public IErrorListener ErrorListener
         {
             get;
         }

src/AsmResolver.DotNet/ModuleDefinition.cs

@@ -1231,14 +1231,18 @@ public void Write(IBinaryStreamWriter writer, IPEImageBuilder imageBuilder, IPEF
         public IPEImage ToPEImage(IPEImageBuilder imageBuilder)
         {
             var result = imageBuilder.CreateImage(this);
-            if (result.DiagnosticBag.HasErrors)
+            if (result.ErrorListener is DiagnosticBag diagnosticBag && diagnosticBag.HasErrors)
             {
                 throw new AggregateException(
                     "Construction of the PE image failed with one or more errors.",
-                    result.DiagnosticBag.Exceptions);
+                    diagnosticBag.Exceptions);
+            }
+            else if (result.HasFailed)
+            {
+                throw new Exception("Construction of the PE image failed.");
             }
 
-            return result.ConstructedImage!;
+            return result.ConstructedImage;
         }
     }
  }

test/AsmResolver.DotNet.Tests/Builder/TokenPreservation/TokenPreservationTestBase.cs

@@ -39,7 +39,10 @@ protected static ModuleDefinition RebuildAndReloadModule(ModuleDefinition module
 
             var result = builder.CreateImage(module);
             if (result.HasFailed)
-                throw new AggregateException(result.DiagnosticBag.Exceptions);
+                if (result.ErrorListener is DiagnosticBag diagnosticBag)
+                    throw new AggregateException(diagnosticBag.Exceptions);
+                else
+                    throw new Exception("Image creation failed.");
 
             var newImage = result.ConstructedImage;