From 385825d010b7616244b0f42fb0222651b5997cb6 Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Wed, 19 Aug 2020 23:35:12 +0200
Subject: [PATCH] Improve registration error messages

- Don't print the raw IRC message, since we already show the original
  error message
- Avoid double-printing "registration failed"
---
 upstream.go | 17 ++++++++++++++---
 user.go     |  8 ++++++--
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/upstream.go b/upstream.go
index 29613af..4ec704d 100644
--- a/upstream.go
+++ b/upstream.go
@@ -32,6 +32,12 @@ var permanentUpstreamCaps = map[string]bool{
 	"server-time":      true,
 }
 
+type registrationError string
+
+func (err registrationError) Error() string {
+	return fmt.Sprintf("registration error: %v", string(err))
+}
+
 type upstreamChannel struct {
 	Name         string
 	conn         *upstreamConn
@@ -1357,7 +1363,8 @@ func (uc *upstreamConn) handleMessage(msg *irc.Message) error {
 		return fmt.Errorf("fatal server error: %v", text)
 	case irc.ERR_PASSWDMISMATCH, irc.ERR_ERRONEUSNICKNAME, irc.ERR_NICKNAMEINUSE, irc.ERR_NICKCOLLISION, irc.ERR_UNAVAILRESOURCE, irc.ERR_NOPERMFORHOST, irc.ERR_YOUREBANNEDCREEP:
 		if !uc.registered {
-			return fmt.Errorf("registration failed: %v", msg.Params[len(msg.Params)-1])
+			text := msg.Params[len(msg.Params)-1]
+			return registrationError(text)
 		}
 		fallthrough
 	default:
@@ -1526,8 +1533,12 @@ func (uc *upstreamConn) runUntilRegistered() error {
 		}
 
 		if err := uc.handleMessage(msg); err != nil {
-			msg.Tags = nil // prevent message tags from cluttering logs
-			return fmt.Errorf("failed to handle message %q: %v", msg, err)
+			if _, ok := err.(registrationError); ok {
+				return err
+			} else {
+				msg.Tags = nil // prevent message tags from cluttering logs
+				return fmt.Errorf("failed to handle message %q: %v", msg, err)
+			}
 		}
 	}
 
diff --git a/user.go b/user.go
index 6b9512a..1febc43 100644
--- a/user.go
+++ b/user.go
@@ -140,8 +140,12 @@ func (net *network) run() {
 
 		uc.register()
 		if err := uc.runUntilRegistered(); err != nil {
-			uc.logger.Printf("failed to register: %v", err)
-			net.user.events <- eventUpstreamConnectionError{net, fmt.Errorf("failed to register: %v", err)}
+			text := err.Error()
+			if regErr, ok := err.(registrationError); ok {
+				text = string(regErr)
+			}
+			uc.logger.Printf("failed to register: %v", text)
+			net.user.events <- eventUpstreamConnectionError{net, fmt.Errorf("failed to register: %v", text)}
 			uc.Close()
 			continue
 		}