BufferTextWriter bugs

https://github.com/microsoft/vs-streamjsonrpc/issues/303 calls out a few exceptions that seem to be thrown erratically as if there’s a race condition, or perhaps specific writing patterns that cause the BufferTextWriter to fail.

[joshlang]

It would be difficult to extra a minimal repo, unfortunately.

Here’s another stack traces:

Error writing JSON RPC Result: InvalidOperationException: Stack empty.//StreamError/System.InvalidOperationException: Stack empty.
   at System.Collections.Generic.Stack`1.ThrowForEmptyStack()
   at System.Collections.Generic.Stack`1.Pop()
   at Nerdbank.Streams.Sequence`1.GetSegment(Int32 sizeHint)
   at Nerdbank.Streams.Sequence`1.GetMemory(Int32 sizeHint)
   at Nerdbank.Streams.BufferTextWriter.EncodeCharacters(Boolean flushEncoder)
   at Nerdbank.Streams.BufferTextWriter.Write(ReadOnlySpan`1 buffer)
   at Nerdbank.Streams.BufferTextWriter.Write(String value)
   at Newtonsoft.Json.Utilities.JavaScriptUtils.WriteEscapedJavaScriptString(TextWriter writer, String s, Char delimiter, Boolean appendDelimiters, Boolean[] charEscapeFlags, StringEscapeHandling stringEscapeHandling, IArrayPool`1 bufferPool, Char[]& writeBuffer)
   at Newtonsoft.Json.JsonTextWriter.WriteEscapedString(String value, Boolean quote)
   at Newtonsoft.Json.JsonTextWriter.WriteValue(String value)
   at Newtonsoft.Json.Linq.JValue.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JProperty.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JObject.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JArray.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JProperty.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JObject.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JProperty.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JObject.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JProperty.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at Newtonsoft.Json.Linq.JObject.WriteTo(JsonWriter writer, JsonConverter[] converters)
   at StreamJsonRpc.JsonMessageFormatter.WriteJToken(IBufferWriter`1 contentBuffer, JToken json)
   at StreamJsonRpc.JsonMessageFormatter.Serialize(IBufferWriter`1 contentBuffer, JsonRpcMessage message)
   at StreamJsonRpc.WebSocketMessageHandler.WriteCoreAsync(JsonRpcMessage content, CancellationToken cancellationToken)
   at StreamJsonRpc.MessageHandlerBase.WriteAsync(JsonRpcMessage content, CancellationToken cancellationToken)
   at StreamJsonRpc.JsonRpc.HandleRpcAsync(JsonRpcMessage rpc)

Again, after happening, we’re stuck in this connect/disconnect loop:

Error writing JSON RPC Result: InvalidOperationException: This instance must be flushed before being reinitialized.//StreamError/System.InvalidOperationException: This instance must be flushed before being reinitialized.
   at Microsoft.Verify.Operation(Boolean condition, String message)
   at Nerdbank.Streams.BufferTextWriter.Initialize(IBufferWriter`1 bufferWriter, Encoding encoding)
   at StreamJsonRpc.JsonMessageFormatter.WriteJToken(IBufferWriter`1 contentBuffer, JToken json)
   at StreamJsonRpc.JsonMessageFormatter.Serialize(IBufferWriter`1 contentBuffer, JsonRpcMessage message)
   at StreamJsonRpc.WebSocketMessageHandler.WriteCoreAsync(JsonRpcMessage content, CancellationToken cancellationToken)
   at StreamJsonRpc.MessageHandlerBase.WriteAsync(JsonRpcMessage content, CancellationToken cancellationToken)
   at StreamJsonRpc.JsonRpc.HandleRpcAsync(JsonRpcMessage rpc)

[AArnott]

You’re quite welcome.