From b28c22ce460c727cb52359a56d8cb7a49d6496c6 Mon Sep 17 00:00:00 2001
From: Duco van Amstel <duco.vanamstel@gmail.com>
Date: Mon, 26 Nov 2018 08:59:49 +0000
Subject: [PATCH] Add a log message to Slack topic extraction

---
 bridge/slack/helpers.go | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/bridge/slack/helpers.go b/bridge/slack/helpers.go
index c8a06c5b..b8d24832 100644
--- a/bridge/slack/helpers.go
+++ b/bridge/slack/helpers.go
@@ -271,7 +271,7 @@ var (
 
 func extractTopicOrPurpose(text string) (string, string) {
 	r := topicOrPurposeRE.FindStringSubmatch(text)
-	if len(r) >= 5 {
+	if len(r) == 5 {
 		action, updateType, extracted := r[2], r[3], r[4]
 		switch action {
 		case "set":
@@ -280,7 +280,8 @@ func extractTopicOrPurpose(text string) (string, string) {
 			return updateType, ""
 		}
 	}
-	return "unknown", ""
+	b.Log.Warnf("Encountered channel topic or purpose change message with unexpected format: %s", text)
+	return "unknown, ""
 }
 
 // @see https://api.slack.com/docs/message-formatting#linking_to_channels_and_users