Improve RestException logging

NetCord/Rest/RestError.cs

@@ -3,7 +3,7 @@
 
 namespace NetCord.Rest;
 
-public class RestError(int code, string message, IRestErrorGroup? error)
+public sealed class RestError(int code, string message, IRestErrorGroup? error)
 {
     [JsonPropertyName("code")]
     public int Code { get; } = code;
@@ -14,6 +14,8 @@ public class RestError(int code, string message, IRestErrorGroup? error)
     [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
     [JsonPropertyName("errors")]
     public IRestErrorGroup? Error { get; } = error;
+
+    public override string ToString() => JsonSerializer.Serialize(this, Serialization.Default.RestError);
 }
 
 [JsonConverter(typeof(IRestErrorGroupConverter))]

NetCord/Rest/RestException.cs

@@ -46,4 +46,52 @@ private static string GetMessage(HttpStatusCode statusCode, string? reasonPhrase
     public string? ReasonPhrase { get; }
 
     public RestError? Error { get; }
+
+    public override string ToString()
+    {
+        const string ClassName = "NetCord.Rest.RestException";
+
+        var message = Message;
+        var stackTrace = StackTrace;
+        string? jsonError;
+
+        int length = ClassName.Length + 2 + message.Length;
+
+        if (Error is { } error)
+        {
+            jsonError = error.ToString();
+            length += Environment.NewLine.Length + jsonError.Length;
+        }
+        else
+            jsonError = null;
+
+        if (stackTrace is not null)
+            length += Environment.NewLine.Length + stackTrace.Length;
+
+        return string.Create(length, (Message: message, StackTrace: stackTrace, JsonError: jsonError), static (span, state) =>
+        {
+            Write(ClassName, ref span);
+
+            Write(": ", ref span);
+            Write(state.Message, ref span);
+
+            if (state.JsonError is { } jsonError)
+            {
+                Write(Environment.NewLine, ref span);
+                Write(jsonError, ref span);
+            }
+
+            if (state.StackTrace is { } stackTrace)
+            {
+                Write(Environment.NewLine, ref span);
+                Write(stackTrace, ref span);
+            }
+        });
+
+        static void Write(string source, ref Span<char> dest)
+        {
+            source.CopyTo(dest);
+            dest = dest[source.Length..];
+        }
+    }
 }

Tests/NetCord.Test/Program.cs

@@ -1,6 +1,5 @@
 using System.Reflection;
 using System.Runtime.InteropServices;
-using System.Text.Json;
 
 using Microsoft.Extensions.DependencyInjection;
 
@@ -148,10 +147,9 @@ private static async Task Main()
         {
             await manager.CreateCommandsAsync(_client.Rest, _client.Id, true);
         }
-        catch (RestException ex)
+        catch (Exception ex)
         {
-            var error = ex.Error;
-            Console.WriteLine(error is null ? "No error returned." : JsonSerializer.Serialize(error, Discord.SerializerOptions));
+            Console.WriteLine(ex);
         }
 
         await Task.Delay(-1);