Ion Reader expects wrong character at end of list of structs for text files

[biolore]

When reading a list of structs from a text file/string, such as [{number:0},{number:1},{number:2}], the following exception is thrown at the end of the list:
System.FormatException: Illegal character: expected '}' character but encountered ']'

Below is a stub program which writes and then reads a list of simple structs in both a text and binary file formats, adapted from the cookbook's reading and writing ion data section.

using System;
using System.IO;
using Amazon.IonDotnet;
using Amazon.IonDotnet.Builders;

namespace IonScratchpad
{
    class Program
    {
        private const string TextFileName = "structList.txt.ion";
        private const string BinaryFileName = "structList.bin.ion";

        static void Main(string[] args)
        {
            // Write Binary
            WriteBinaryFile();

            // Read Binary
            ReadFile(BinaryFileName);

            // Write Text
            WriteTextFile();

            // Read Text
            ReadFile(TextFileName);
        }

        private static void ReadFile(string fileName)
        {
            try
            {
                Console.WriteLine($"Reading {fileName} with {nameof(IonReaderBuilder)}");
                using Stream fs = File.OpenRead(fileName);
                using IIonReader reader = IonReaderBuilder.Build(fs);
                ReadListOfStruct(reader);
                Console.WriteLine("Done reading binary file");
            }
            catch (Exception e)
            {
                Console.WriteLine($"Hit exception while reading {fileName}: {e.Message}");
            }
        }

        private static void ReadListOfStruct(IIonReader reader)
        {
            reader.MoveNext(); // position the reader at the first value, a struct
            reader.StepIn(); // step into the list
            while (reader.MoveNext() != IonType.None)
            {
                reader.StepIn(); // step into the struct
                reader.MoveNext(); // position the reader at the first value in the struct
                string fieldName = reader.CurrentFieldName; // retrieve the current value's field name
                int value = reader.IntValue(); // retrieve the current value's string value
                reader.StepOut(); // step out of the struct
                Console.WriteLine(fieldName + ": " + value);
            }

            reader.StepOut(); // step out of the list
        }

        private static void WriteBinaryFile()
        {
            try
            {
                Console.WriteLine($"Writing {BinaryFileName} with {nameof(IonBinaryWriterBuilder)}");
                using Stream fs = File.Create(BinaryFileName);
                using IIonWriter binaryWriter = IonBinaryWriterBuilder.Build(fs);
                WriteListOfStruct(binaryWriter);
                Console.WriteLine("Done writing binary file");
            }
            catch (Exception e)
            {
                Console.WriteLine($"Hit exception while writing {BinaryFileName}: {e.Message}");
            }
        }

        private static void WriteTextFile()
        {
            try
            {
                Console.WriteLine($"Writing {TextFileName} with {nameof(IonTextWriterBuilder)}");
                using TextWriter tw = new StreamWriter(TextFileName);
                using IIonWriter textWriter = IonTextWriterBuilder.Build(tw);
                WriteListOfStruct(textWriter);
                Console.WriteLine("Done writing text file");
            }
            catch (Exception e)
            {
                Console.WriteLine($"Hit exception while writing {TextFileName}: {e.Message}");
            }
        }

        private static void WriteListOfStruct(IIonWriter writer)
        {
            writer.StepIn(IonType.List);
            for (int i = 0; i < 3; i++)
            {
                writer.StepIn(IonType.Struct); // step into a struct
                writer.SetFieldName("number"); // set the field name for the next value to be written
                writer.WriteInt(i); // write the next value
                writer.StepOut(); // step out of the struct
            }

            writer.StepOut();

            writer.Finish();
        }
    }
}

Output of this stub is as follows:

Writing structList.bin.ion with IonBinaryWriterBuilder
Done writing binary file
Reading structList.bin.ion with IonReaderBuilder
number: 0
number: 1
number: 2
Done reading binary file
Writing structList.txt.ion with IonTextWriterBuilder
Done writing text file
Reading structList.txt.ion with IonReaderBuilder
number: 0
number: 1
number: 2
Hit exception while reading structList.txt.ion: Illegal character: expected '}' character but encountered ']'

And lastly the files generated by the stub are in this zip file: filesMadeByStub.zip

[CoderNate]

This doesn't help explain why the text vs binary versions have different behavior but, as a workaround, after nt value = reader.IntValue(); you can call reader.MoveNext() (which returns IonType.None) before stepping out of the struct.