Fix: NullReference in stack evaluation in xamarin

Author: neolithos

NeoLua/Exceptions.cs

@@ -309,7 +309,7 @@ private string GetChunkName()
 		{
 			var chunkName = info.ChunkName;
 			var methodName = Method.Name;
-			
+
 			return methodName.StartsWith(chunkName)
 				? chunkName
 				: chunkName + "#" + methodName;
@@ -330,19 +330,19 @@ public LuaStackFrameType Type
 		} // func Type
 
 		/// <summary></summary>
-		public string MethodName { get { return info == null ? Method.Name : GetChunkName(); } }
+		public string MethodName => info == null ? Method.Name : GetChunkName();
 		/// <summary></summary>
-		public MethodBase Method { get { return frame.GetMethod(); } }
+		public MethodBase Method => frame.GetMethod();
 		/// <summary></summary>
-		public int ILOffset { get { return frame.GetILOffset(); } }
+		public int ILOffset => frame.GetILOffset();
 		/// <summary></summary>
-		public int NativeOffset { get { return frame.GetNativeOffset(); } }
+		public int NativeOffset => frame.GetNativeOffset();
 		/// <summary></summary>
-		public string FileName { get { return info == null ? frame.GetFileName() : info.FileName; } }
+		public string FileName => info?.FileName ?? frame.GetFileName();
 		/// <summary></summary>
-		public int ColumnNumber { get { return info == null ? frame.GetFileColumnNumber() : info.Column; } }
+		public int ColumnNumber => info?.Column ?? frame.GetFileColumnNumber();
 		/// <summary></summary>
-		public int LineNumber { get { return info == null ? frame.GetFileLineNumber() : info.Line; } }
+		public int LineNumber => info == null ? frame.GetFileLineNumber() : info.Line;
 
 		string ILuaDebugInfo.ChunkName => MethodName;
 		int ILuaDebugInfo.Line => LineNumber;
@@ -392,7 +392,7 @@ public void UpdateStackTrace(LuaStackFrame[] newStackTrace)
 		public IEnumerator<LuaStackFrame> GetEnumerator()
 		{
 			var length = Count;
-			for (int i = 0; i < length; i++)
+			for (var i = 0; i < length; i++)
 				yield return stackTrace[i];
 		} // func GetEnumerator
 
@@ -562,7 +562,7 @@ public static void UnwindException(Exception ex, Func<ILuaDebugInfo> createDebug
 
 			// add trace point
 			luaFrames.Add(new LuaStackFrame(trace.GetFrame(trace.FrameCount - 1), createDebugInfo()));
-
+			
 			currentData.UpdateStackTrace(luaFrames.ToArray());
 		} // func UnwindException
 	} // class LuaExceptionData

NeoLua/Lua.cs

@@ -470,7 +470,7 @@ public static LuaChunk GetChunkFromMethodName(string name)
 		/// <param name="mi"></param>
 		/// <returns></returns>
 		public static LuaChunk GetChunkFromMethodInfo(MethodBase mi)
-			=> GetChunkFromMethodName(mi.Name);
+			=> mi != null ? GetChunkFromMethodName(mi.Name) : null;
 
 		#endregion
 

NeoLua/LuaDebug.cs

@@ -124,7 +124,7 @@ public Expression GetLineInfoExpression(DebugInfoExpression exprDebugInfo)
 					var oldFileName = FileNameConstant.Value as string;
 					var newFileName = exprDebugInfo.Document?.FileName;
 					if (oldFileName != newFileName)
-						FileNameConstant = Expression.Constant(newFileName);
+						FileNameConstant = Expression.Constant(newFileName, typeof(string));
 
 					if (exprDebugInfo.StartLine == 16707566)
 					{