Fix #1052: Use IDocumentationProvider in the CSharpDecompiler API

ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs

@@ -344,6 +344,11 @@ namespace ICSharpCode.Decompiler.CSharp
 			return typeSystemAstBuilder;
 		}
 
+		IDocumentationProvider CreateDefaultDocumentationProvider()
+		{
+			return XmlDocLoader.LoadDocumentation(typeSystem.ModuleDefinition);
+		}
+
 		void RunTransforms(AstNode rootNode, DecompileRun decompileRun, ITypeResolveContext decompilationContext)
 		{
 			var typeSystemAstBuilder = CreateAstBuilder(decompilationContext);
@@ -369,6 +374,7 @@ namespace ICSharpCode.Decompiler.CSharp
 		{
 			var decompilationContext = new SimpleTypeResolveContext(typeSystem.MainAssembly);
 			var decompileRun = new DecompileRun(settings) {
+				DocumentationProvider = DocumentationProvider ?? CreateDefaultDocumentationProvider(),
 				CancellationToken = CancellationToken
 			};
 			syntaxTree = new SyntaxTree();
@@ -433,6 +439,7 @@ namespace ICSharpCode.Decompiler.CSharp
 		{
 			var decompilationContext = new SimpleTypeResolveContext(typeSystem.MainAssembly);
 			var decompileRun = new DecompileRun(settings) {
+				DocumentationProvider = DocumentationProvider ?? CreateDefaultDocumentationProvider(),
 				CancellationToken = CancellationToken
 			};
 			syntaxTree = new SyntaxTree();
@@ -446,7 +453,10 @@ namespace ICSharpCode.Decompiler.CSharp
 
 		public ILTransformContext CreateILTransformContext(ILFunction function)
 		{
-			var decompileRun = new DecompileRun(settings) { CancellationToken = CancellationToken };
+			var decompileRun = new DecompileRun(settings) {
+				DocumentationProvider = DocumentationProvider ?? CreateDefaultDocumentationProvider(),
+				CancellationToken = CancellationToken
+			};
 			RequiredNamespaceCollector.CollectNamespaces(function.Method, typeSystem, decompileRun.Namespaces);
 			return new ILTransformContext(function, typeSystem, DebugInfoProvider, settings) {
 				CancellationToken = CancellationToken,
@@ -474,6 +484,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				throw new ArgumentNullException(nameof(types));
 			var decompilationContext = new SimpleTypeResolveContext(typeSystem.MainAssembly);
 			var decompileRun = new DecompileRun(settings) {
+				DocumentationProvider = DocumentationProvider ?? CreateDefaultDocumentationProvider(),
 				CancellationToken = CancellationToken
 			};
 			syntaxTree = new SyntaxTree();
@@ -509,6 +520,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				throw new InvalidOperationException($"Could not find type definition {fullTypeName} in type system.");
 			var decompilationContext = new SimpleTypeResolveContext(typeSystem.MainAssembly);
 			var decompileRun = new DecompileRun(settings) {
+				DocumentationProvider = DocumentationProvider ?? CreateDefaultDocumentationProvider(),
 				CancellationToken = CancellationToken
 			};
 			syntaxTree = new SyntaxTree();
@@ -546,7 +558,10 @@ namespace ICSharpCode.Decompiler.CSharp
 				throw new ArgumentNullException(nameof(definitions));
 			ITypeDefinition parentTypeDef = null;
 			syntaxTree = new SyntaxTree();
-			var decompileRun = new DecompileRun(settings) { CancellationToken = CancellationToken };
+			var decompileRun = new DecompileRun(settings) {
+				DocumentationProvider = DocumentationProvider ?? CreateDefaultDocumentationProvider(),
+				CancellationToken = CancellationToken
+			};
 			foreach (var entity in definitions) {
 				if (entity.IsNil)
 					throw new ArgumentException("definitions contains null element");

ICSharpCode.Decompiler/CSharp/Transforms/AddXmlDocumentationTransform.cs

@@ -34,18 +34,16 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 	{
 		public void Run(AstNode rootNode, TransformContext context)
 		{
-			if (!context.Settings.ShowXmlDocumentation)
+			if (!context.Settings.ShowXmlDocumentation || context.DecompileRun.DocumentationProvider == null)
 				return;
 			try {
-				var xmldoc = XmlDocLoader.LoadDocumentation(context.TypeSystem.ModuleDefinition);
-				if (xmldoc == null)
-					return;
-				foreach (var entity in rootNode.DescendantsAndSelf.OfType<EntityDeclaration>()) {
-					if (!(entity.GetSymbol() is IEntity symbolicEntity))
+				var provider = context.DecompileRun.DocumentationProvider;
+				foreach (var entityDecl in rootNode.DescendantsAndSelf.OfType<EntityDeclaration>()) {
+					if (!(entityDecl.GetSymbol() is IEntity entity))
 						continue;
-					string doc = xmldoc.GetDocumentation(XmlDocKeyProvider.GetKey(symbolicEntity));
+					string doc = provider.GetDocumentation(entity);
 					if (doc != null) {
-						InsertXmlDocumentation(entity, new StringReader(doc));
+						InsertXmlDocumentation(entityDecl, new StringReader(doc));
 					}
 				}
 			} catch (XmlException ex) {

ICSharpCode.Decompiler/DecompileRun.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Text;
 using System.Threading;
 using ICSharpCode.Decompiler.CSharp.Syntax;
+using ICSharpCode.Decompiler.Documentation;
 using ICSharpCode.Decompiler.TypeSystem;
 
 namespace ICSharpCode.Decompiler
@@ -13,6 +14,7 @@ namespace ICSharpCode.Decompiler
 		public HashSet<string> Namespaces { get; private set; } = new HashSet<string>();
 		public CancellationToken CancellationToken { get; set; }
 		public DecompilerSettings Settings { get; }
+		public IDocumentationProvider DocumentationProvider { get; set; }
 
 		Lazy<CSharp.TypeSystem.UsingScope> usingScope => new Lazy<CSharp.TypeSystem.UsingScope>(() => CreateUsingScope(Namespaces));
 		public CSharp.TypeSystem.UsingScope UsingScope => usingScope.Value;

ICSharpCode.Decompiler/Documentation/XmlDocumentationProvider.cs

@@ -27,8 +27,16 @@ using ICSharpCode.Decompiler.TypeSystem;
 
 namespace ICSharpCode.Decompiler.Documentation
 {
+	/// <summary>
+	/// Provides XML documentation for type and member definitions in source code.
+	/// </summary>
 	public interface IDocumentationProvider
 	{
+		/// <summary>
+		/// Returns the XML documentation for the given <paramref name="entity"/>.
+		/// May return null, if no documentation is present for the entity.
+		/// </summary>
+		/// <exception cref="ArgumentNullException"><paramref name="entity"/> is null.</exception>
 		string GetDocumentation(IEntity entity);
 	}