From 8fb77a7c40cc87eb941de8160e44788db91e5076 Mon Sep 17 00:00:00 2001
From: Alexander Medvednikov <alexander@medvednikov.com>
Date: Wed, 25 Mar 2026 16:42:19 +0300
Subject: [PATCH] net.smtp: separate config from client struct (fixes #19928)

---
 examples/smtp/mail.v      |  2 +-
 vlib/net/smtp/smtp.v      | 27 +++++++++++++--------------
 vlib/net/smtp/smtp_test.v | 19 +++++++++++++++++--
 3 files changed, 31 insertions(+), 17 deletions(-)

diff --git a/examples/smtp/mail.v b/examples/smtp/mail.v
index 118e1b2f3..4a41582c8 100644
--- a/examples/smtp/mail.v
+++ b/examples/smtp/mail.v
@@ -19,7 +19,7 @@ fn main() {
 	to := os.input('To: ')
 	subject := os.input('Subject: ')
 	body := os.input('Body: ')
-	client_cfg := smtp.Client{
+	client_cfg := smtp.Config{
 		server:   mailserver
 		from:     from
 		port:     mailport
diff --git a/vlib/net/smtp/smtp.v b/vlib/net/smtp/smtp.v
index b703a2aa9..3d71224a1 100644
--- a/vlib/net/smtp/smtp.v
+++ b/vlib/net/smtp/smtp.v
@@ -28,12 +28,8 @@ pub enum BodyType {
 	html
 }
 
-// Client configures an SMTP connection. `timeout` applies to the underlying TCP reads and writes.
-pub struct Client {
-mut:
-	conn     net.TcpConn
-	ssl_conn &ssl.SSLConn = unsafe { nil }
-	reader   ?&io.BufferedReader
+// Config stores the settings used to connect a new SMTP client.
+pub struct Config {
 pub:
 	server   string
 	port     int = 25
@@ -42,7 +38,14 @@ pub:
 	from     string
 	ssl      bool
 	starttls bool
-	timeout  time.Duration = net.tcp_default_read_timeout
+}
+
+pub struct Client {
+	Config
+mut:
+	conn     net.TcpConn
+	ssl_conn &ssl.SSLConn = unsafe { nil }
+	reader   ?&io.BufferedReader
 pub mut:
 	is_open   bool
 	encrypted bool
@@ -70,13 +73,13 @@ pub:
 }
 
 // new_client returns a new SMTP client and connects to it
-pub fn new_client(config Client) !&Client {
+pub fn new_client(config Config) !&Client {
 	if config.ssl && config.starttls {
 		return error('Can not use both implicit SSL and STARTTLS')
 	}
 
 	mut c := &Client{
-		...config
+		Config: config
 	}
 	c.reconnect()!
 	return c
@@ -88,11 +91,7 @@ pub fn (mut c Client) reconnect() ! {
 		return error('Already connected to server')
 	}
 
-	mut conn := net.dial_tcp('${c.server}:${c.port}') or {
-		return error('Connecting to server failed')
-	}
-	conn.set_read_timeout(c.timeout)
-	conn.set_write_timeout(c.timeout)
+	conn := net.dial_tcp('${c.server}:${c.port}') or { return error('Connecting to server failed') }
 	c.conn = conn
 
 	if c.ssl || c.encrypted {
diff --git a/vlib/net/smtp/smtp_test.v b/vlib/net/smtp/smtp_test.v
index 603a471f9..2c6f6e9a5 100644
--- a/vlib/net/smtp/smtp_test.v
+++ b/vlib/net/smtp/smtp_test.v
@@ -10,7 +10,7 @@ fn fn_errors(mut c smtp.Client, m smtp.Mail) bool {
 }
 
 fn send_mail(starttls bool) {
-	client_cfg := smtp.Client{
+	client_cfg := smtp.Config{
 		server:   'smtp.mailtrap.io'
 		port:     465
 		from:     'dev@vlang.io'
@@ -108,7 +108,7 @@ fn test_smtp_implicit_ssl() {
 		return
 	}
 
-	client_cfg := smtp.Client{
+	client_cfg := smtp.Config{
 		server:   'smtp.gmail.com'
 		port:     465
 		from:     ''
@@ -125,6 +125,21 @@ fn test_smtp_implicit_ssl() {
 	assert client.is_open && client.encrypted
 }
 
+fn test_new_client_rejects_conflicting_tls_modes() {
+	client_cfg := smtp.Config{
+		server:   'smtp.example.com'
+		ssl:      true
+		starttls: true
+	}
+
+	smtp.new_client(client_cfg) or {
+		assert err.msg() == 'Can not use both implicit SSL and STARTTLS'
+		return
+	}
+
+	assert false
+}
+
 fn test_smtp_multiple_recipients() {
 	$if !network ? {
 		return
-- 
2.39.5