From 062614ee7ae053a94c9dd6d06c517c6a139134ff Mon Sep 17 00:00:00 2001
From: Martin Dosch <martin@mdosch.de>
Date: Thu, 2 Mar 2023 20:28:51 +0100
Subject: [PATCH] Allow JIDs without localpart.

---
 CHANGELOG.md |  1 +
 jid.go       | 15 +++++++++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fc2d8bc..2fe2a6c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@
 ### Changed
 - Print `--help` output to stdout instead of stderr.
 - Print sent stanzas when `--debug` is used (via go-xmpp commit 9129a110df1b).
+- Allow JIDs without localpart.
 
 ## [v0.5.6] 2022-11-11
 ### Added
diff --git a/jid.go b/jid.go
index 95ff508..0c5e5be 100644
--- a/jid.go
+++ b/jid.go
@@ -50,7 +50,7 @@ func MarshalJID(input string) (string, error) {
 	switch {
 	case sep == -1:
 		// There is no @ sign, and therefore no localpart.
-		return input, errors.New("Invalid JID: " + input)
+		domainpart = s
 	case sep == 0:
 		// The JID starts with an @ sign (invalid empty localpart)
 		err = errors.New("Invalid JID:" + input)
@@ -71,17 +71,24 @@ func MarshalJID(input string) (string, error) {
 	//    are taken.
 
 	domainpart = strings.TrimSuffix(domainpart, ".")
+	var jid string
 
 	if !utf8.ValidString(localpart) || !utf8.ValidString(domainpart) || !utf8.ValidString(resourcepart) {
 		return input, errors.New("Invalid JID: " + input)
 	}
 
-	if localpart == "" || domainpart == "" {
+	if domainpart == "" {
 		return input, errors.New("Invalid JID: " + input)
 	}
 
+	if localpart == "" {
+		jid = domainpart
+	} else {
+		jid = localpart + "@" + domainpart
+	}
+
 	if resourcepart == "" {
-		return localpart + "@" + domainpart, err
+		return jid, err
 	}
-	return localpart + "@" + domainpart + "/" + resourcepart, err
+	return jid + "/" + resourcepart, err
 }