Fix #2402: ArgumentNullException in IL mode for tooltips when decompiling bundle members.

ILSpy/Analyzers/AnalyzerEntityTreeNode.cs

@@ -17,7 +17,6 @@
 // DEALINGS IN THE SOFTWARE.
 
 using System.Collections.Generic;
-using System.Reflection.Metadata;
 using System.Windows;
 
 using ICSharpCode.Decompiler.TypeSystem;
@@ -41,7 +40,7 @@ namespace ICSharpCode.ILSpy.Analyzers
 				MessageBox.Show(Properties.Resources.CannotAnalyzeMissingRef, "ILSpy");
 				return;
 			}
-			MainWindow.Instance.JumpToReference(new EntityReference(this.Member.ParentModule.PEFile.FileName, this.Member.MetadataToken));
+			MainWindow.Instance.JumpToReference(new EntityReference(this.Member.ParentModule.PEFile, this.Member.MetadataToken));
 		}
 
 		public override bool HandleAssemblyListChanged(ICollection<LoadedAssembly> removedAssemblies, ICollection<LoadedAssembly> addedAssemblies)

ILSpy/EntityReference.cs

@@ -15,8 +15,8 @@
 // FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
+#nullable enable
 
-using System;
 using System.Diagnostics;
 using System.Reflection.Metadata;
 
@@ -27,6 +27,7 @@ namespace ICSharpCode.ILSpy
 	[DebuggerDisplay("EntityReference Module={Module}, Handle={Handle}, Protocol={Protocol}")]
 	public class EntityReference
 	{
+		readonly PEFile? peFile;
 		public string Module { get; }
 		public Handle Handle { get; }
 		public string Protocol { get; }
@@ -38,15 +39,23 @@ namespace ICSharpCode.ILSpy
 			this.Protocol = "decompile";
 		}
 
-		public EntityReference(string protocol, string moduleFileName, Handle handle)
+		public EntityReference(string? protocol, string moduleFileName, Handle handle)
 			: this(moduleFileName, handle)
 		{
 			this.Protocol = protocol ?? "decompile";
 		}
 
-		public PEFile ResolveAssembly(AssemblyList context)
+		public EntityReference(PEFile module, Handle handle, string protocol = "decompile")
 		{
-			return context.FindAssembly(Module)?.GetPEFileOrNull();
+			this.peFile = module;
+			this.Module = module.FileName;
+			this.Handle = handle;
+			this.Protocol = protocol;
+		}
+
+		public PEFile? ResolveAssembly(AssemblyList context)
+		{
+			return peFile ?? context.FindAssembly(Module)?.GetPEFileOrNull();
 		}
 	}
 }

ILSpy/Metadata/GoToTokenCommand.cs

@@ -22,7 +22,6 @@ using System.Reflection;
 using System.Reflection.Metadata.Ecma335;
 using System.Windows;
 using System.Windows.Controls;
-using System.Windows.Input;
 using System.Windows.Media;
 
 using ICSharpCode.Decompiler.Metadata;
@@ -37,7 +36,7 @@ namespace ICSharpCode.ILSpy.Commands
 		public void Execute(TextViewContext context)
 		{
 			int token = GetSelectedToken(context.DataGrid, out PEFile module).Value;
-			MainWindow.Instance.JumpToReference(new EntityReference("metadata", module.FileName, MetadataTokens.Handle(token)));
+			MainWindow.Instance.JumpToReference(new EntityReference(module, MetadataTokens.Handle(token), protocol: "metadata"));
 		}
 
 		public bool IsEnabled(TextViewContext context)

ILSpy/TextView/AvalonEditTextOutput.cs

@@ -270,7 +270,7 @@ namespace ICSharpCode.ILSpy.TextView
 			{
 				this.DefinitionLookup.AddDefinition((module, handle), this.TextLength);
 			}
-			references.Add(new ReferenceSegment { StartOffset = start, EndOffset = end, Reference = new EntityReference(protocol, module.FileName, handle), IsDefinition = isDefinition });
+			references.Add(new ReferenceSegment { StartOffset = start, EndOffset = end, Reference = new EntityReference(module, handle, protocol), IsDefinition = isDefinition });
 		}
 
 		public void WriteReference(IType type, string text, bool isDefinition = false)

ILSpy/TextView/DecompilerTextView.cs

@@ -19,7 +19,6 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
-using System.ComponentModel.Composition;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
@@ -49,8 +48,6 @@ using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.CSharp.OutputVisitor;
 using ICSharpCode.Decompiler.CSharp.ProjectDecompiler;
 using ICSharpCode.Decompiler.Documentation;
-using ICSharpCode.Decompiler.Metadata;
-using ICSharpCode.Decompiler.Output;
 using ICSharpCode.Decompiler.TypeSystem;
 using ICSharpCode.ILSpy.AvalonEdit;
 using ICSharpCode.ILSpy.Options;
@@ -405,6 +402,8 @@ namespace ICSharpCode.ILSpy.TextView
 			else if (segment.Reference is EntityReference unresolvedEntity)
 			{
 				var module = unresolvedEntity.ResolveAssembly(MainWindow.Instance.CurrentAssemblyList);
+				if (module == null)
+					return null;
 				var typeSystem = new DecompilerTypeSystem(module,
 					module.GetAssemblyResolver(),
 					TypeSystemOptions.Default | TypeSystemOptions.Uncached);