Add validation

Debugger/ILSpy.Debugger/Services/Debugger/WindowsDebugger.cs

@@ -826,9 +826,19 @@ namespace ILSpy.Debugger.Services
 				if (CodeMappingsStorage.GetSourceCodeFromMetadataTokenAndOffset(token, ilOffset, out type, out line)) {
 					DebuggerService.JumpToCurrentLine(type, line, 0, line, 0);
 				} else {
+					// is possible that the type is not decompiled yet, so we must do a decompilation on demand
+					DecompileOnDemand(frame);
+				}
+			}
+		}
+
+		void DecompileOnDemand(StackFrame frame)
+		{
 			var debugType = frame.MethodInfo.DeclaringType;
-					string fullName = debugType.Namespace + "." + debugType.Name;
+			uint token = (uint)frame.MethodInfo.MetadataToken;
+			int ilOffset = frame.IP;
 			
+			string fullName = debugType.Namespace + "." + debugType.Name;
 			if (DebugData.LoadedAssemblies == null)
 				Continue();
 			else {
@@ -840,28 +850,27 @@ namespace ILSpy.Debugger.Services
 							break;
 						}
 					}
-							
 					if (typeRef != null)
 						break;
 				}
-						
 				if (typeRef != null) {
 					// decompile on demand
 					AstBuilder builder = new AstBuilder(new DecompilerContext());
 					builder.AddType(typeRef.Resolve());
 					builder.GenerateCode(new PlainTextOutput());
 					
-							// jump
+					// try jump
+					int line;
+					TypeDefinition type;
 					if (CodeMappingsStorage.GetSourceCodeFromMetadataTokenAndOffset(token, ilOffset, out type, out line)) {
 						DebuggerService.JumpToCurrentLine(type, line, 0, line, 0);
 					} else {
-								StepOut();
+						// continue since we cannot find the debugged type
+						Continue();
 					}
 				} else {
 					// continue since we cannot find the debugged type
-							StepOut();
+					Continue();
-						}
-					}
 				}
 			}
 		}

ICSharpCode.Decompiler/CodeMappings.cs

@@ -48,7 +48,9 @@ namespace ICSharpCode.Decompiler
 			var resultList = new List<int>();
 			
 			// add list for the current source code line
-			var currentList = MemberMapping.MemberCodeMappings.FindAll(m => m.SourceCodeLine == this.SourceCodeLine);
+			var currentList = MemberMapping.MemberCodeMappings
+				.FindAll(m => m.SourceCodeLine == this.SourceCodeLine)
+				.OrderBy(m => m.ILInstructionOffset.From);
 			foreach (var element in currentList.Distinct(new SourceCodeMappingComparer())) {
 				resultList.Add(element.ILInstructionOffset.From);
 				resultList.Add(element.ILInstructionOffset.To);
@@ -166,6 +168,12 @@ namespace ICSharpCode.Decompiler
 			this MethodDefinition member,
 			ConcurrentDictionary<string, List<MemberMapping>> codeMappings)
 		{
+			if (member == null || !member.HasBody)
+				return null;
+			
+			if (codeMappings == null)
+				throw new ArgumentNullException("CodeMappings storage must be valid!");
+			
 			// create IL/CSharp code mappings - used in debugger
 			MemberMapping currentMemberMapping = null;
 			if (codeMappings.ContainsKey(member.DeclaringType.FullName)) {
@@ -198,6 +206,9 @@ namespace ICSharpCode.Decompiler
 			int lineNumber,
 			out uint metadataToken)
 		{
+			if (codeMappings == null)
+				throw new ArgumentNullException("CodeMappings storage must be valid!");
+			
 			if (!codeMappings.ContainsKey(typeName)) {
 				metadataToken = 0;
 				return null;