From 989bf939b586ae90c347a9b6b3053d6481bde78d Mon Sep 17 00:00:00 2001
From: Andrew Arnott <andrewarnott@gmail.com>
Date: Wed, 4 Dec 2019 10:38:08 -0700
Subject: [PATCH] Include RPC server stack trace in
 RemoteInvocationException.ToString()

It isn't always possible to do, but when the server provides a `CommonErrorData` object, we certainly can do it.
I endeavored to copy the string format that .NET uses for its own exception formatting, including for inner exceptions.

Closes #369
---
 .../Exceptions/RemoteInvocationException.cs   | 52 +++++++++++++++++++
 .../netcoreapp2.1/PublicAPI.Unshipped.txt     |  1 +
 .../netstandard2.0/PublicAPI.Unshipped.txt    |  1 +
 3 files changed, 54 insertions(+)

diff --git a/src/StreamJsonRpc/Exceptions/RemoteInvocationException.cs b/src/StreamJsonRpc/Exceptions/RemoteInvocationException.cs
index 6b3bf59a..c37292b2 100644
--- a/src/StreamJsonRpc/Exceptions/RemoteInvocationException.cs
+++ b/src/StreamJsonRpc/Exceptions/RemoteInvocationException.cs
@@ -4,6 +4,8 @@
 namespace StreamJsonRpc
 {
     using System;
+    using System.IO;
+    using System.Text;
     using Newtonsoft.Json.Linq;
     using StreamJsonRpc.Protocol;
 
@@ -83,5 +85,55 @@ protected RemoteInvocationException(
         /// The default implementation of this method produces a <see cref="CommonErrorData"/> object.
         /// </remarks>
         public object? DeserializedErrorData { get; }
+
+        /// <inheritdoc/>
+        public override string ToString()
+        {
+            string result = base.ToString();
+
+            if (this.DeserializedErrorData is CommonErrorData errorData)
+            {
+                var builder = new StringBuilder(result);
+                builder.AppendLine();
+                builder.AppendLine("RPC server exception:");
+                builder.AppendLine($"{errorData.TypeName}: {errorData.Message}");
+                if (errorData.Inner is object)
+                {
+                    ContributeInnerExceptionDetails(builder, errorData.Inner);
+                }
+
+                ContributeStackTrace(builder, errorData);
+                result = builder.ToString();
+            }
+
+            return result;
+        }
+
+        private static void ContributeInnerExceptionDetails(StringBuilder builder, CommonErrorData errorData)
+        {
+            builder.AppendLine($" ---> {errorData.TypeName}: {errorData.Message}");
+            if (errorData.Inner is object)
+            {
+                ContributeInnerExceptionDetails(builder, errorData.Inner);
+            }
+
+            ContributeStackTrace(builder, errorData);
+
+            builder.AppendLine("   --- End of inner exception stack trace ---");
+        }
+
+        private static void ContributeStackTrace(StringBuilder builder, CommonErrorData errorData)
+        {
+            if (errorData.StackTrace != null)
+            {
+                using (var sr = new StringReader(errorData.StackTrace))
+                {
+                    while (sr.ReadLine() is string line)
+                    {
+                        builder.AppendLine($"   {line}");
+                    }
+                }
+            }
+        }
     }
 }
diff --git a/src/StreamJsonRpc/netcoreapp2.1/PublicAPI.Unshipped.txt b/src/StreamJsonRpc/netcoreapp2.1/PublicAPI.Unshipped.txt
index daac84fb..b64c3f41 100644
--- a/src/StreamJsonRpc/netcoreapp2.1/PublicAPI.Unshipped.txt
+++ b/src/StreamJsonRpc/netcoreapp2.1/PublicAPI.Unshipped.txt
@@ -72,6 +72,7 @@ const StreamJsonRpc.Reflection.MessageFormatterEnumerableTracker.TokenPropertyNa
 const StreamJsonRpc.Reflection.MessageFormatterEnumerableTracker.ValuesPropertyName = "values" -> string
 override StreamJsonRpc.PipeMessageHandler.DisposeReader() -> void
 override StreamJsonRpc.PipeMessageHandler.DisposeWriter() -> void
+override StreamJsonRpc.RemoteInvocationException.ToString() -> string
 override StreamJsonRpc.RemoteMethodNotFoundException.GetObjectData(System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context) -> void
 override StreamJsonRpc.RequestId.Equals(object obj) -> bool
 override StreamJsonRpc.RequestId.GetHashCode() -> int
diff --git a/src/StreamJsonRpc/netstandard2.0/PublicAPI.Unshipped.txt b/src/StreamJsonRpc/netstandard2.0/PublicAPI.Unshipped.txt
index daac84fb..b64c3f41 100644
--- a/src/StreamJsonRpc/netstandard2.0/PublicAPI.Unshipped.txt
+++ b/src/StreamJsonRpc/netstandard2.0/PublicAPI.Unshipped.txt
@@ -72,6 +72,7 @@ const StreamJsonRpc.Reflection.MessageFormatterEnumerableTracker.TokenPropertyNa
 const StreamJsonRpc.Reflection.MessageFormatterEnumerableTracker.ValuesPropertyName = "values" -> string
 override StreamJsonRpc.PipeMessageHandler.DisposeReader() -> void
 override StreamJsonRpc.PipeMessageHandler.DisposeWriter() -> void
+override StreamJsonRpc.RemoteInvocationException.ToString() -> string
 override StreamJsonRpc.RemoteMethodNotFoundException.GetObjectData(System.Runtime.Serialization.SerializationInfo info, System.Runtime.Serialization.StreamingContext context) -> void
 override StreamJsonRpc.RequestId.Equals(object obj) -> bool
 override StreamJsonRpc.RequestId.GetHashCode() -> int