From c656226fd3a0b786dbe4fe859f42215882952efd Mon Sep 17 00:00:00 2001
From: Winni Neessen <wn@neessen.net>
Date: Fri, 8 Nov 2024 15:51:17 +0100
Subject: [PATCH] Add XOAuth2 authentication tests to SMTP package

Introduces two tests for XOAuth2 authentication in the SMTP package. The first test ensures successful authentication with valid credentials, while the second test verifies that authentication fails with incorrect settings.
---
 smtp/smtp_test.go | 58 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/smtp/smtp_test.go b/smtp/smtp_test.go
index cf3760c..5846e7f 100644
--- a/smtp/smtp_test.go
+++ b/smtp/smtp_test.go
@@ -978,6 +978,64 @@ func TestXOAuth2Auth(t *testing.T) {
 			t.Fatalf("got %q; want empty response", resp[2])
 		}
 	})
+	t.Run("XOAuth2 authentication on test server succeeds", func(t *testing.T) {
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+		PortAdder.Add(1)
+		serverPort := int(TestServerPortBase + PortAdder.Load())
+		featureSet := "250-AUTH XOAUTH2\r\n250-8BITMIME\r\n250-DSN\r\n250 SMTPUTF8"
+		go func() {
+			if err := simpleSMTPServer(ctx, t, &serverProps{
+				FeatureSet: featureSet,
+				ListenPort: serverPort},
+			); err != nil {
+				t.Errorf("failed to start test server: %s", err)
+				return
+			}
+		}()
+		time.Sleep(time.Millisecond * 30)
+
+		auth := XOAuth2Auth("user", "token")
+		client, err := Dial(fmt.Sprintf("%s:%d", TestServerAddr, serverPort))
+		if err != nil {
+			t.Fatalf("failed to connect to test server: %s", err)
+		}
+		t.Cleanup(func() {
+			if err = client.Close(); err != nil {
+				t.Errorf("failed to close client connection: %s", err)
+			}
+		})
+		if err = client.Auth(auth); err != nil {
+			t.Errorf("failed to authenticate to test server: %s", err)
+		}
+	})
+	t.Run("XOAuth2 authentication on test server fails", func(t *testing.T) {
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+		PortAdder.Add(1)
+		serverPort := int(TestServerPortBase + PortAdder.Load())
+		featureSet := "250-AUTH XOAUTH2\r\n250-8BITMIME\r\n250-DSN\r\n250 SMTPUTF8"
+		go func() {
+			if err := simpleSMTPServer(ctx, t, &serverProps{
+				FailOnAuth: true,
+				FeatureSet: featureSet,
+				ListenPort: serverPort},
+			); err != nil {
+				t.Errorf("failed to start test server: %s", err)
+				return
+			}
+		}()
+		time.Sleep(time.Millisecond * 30)
+
+		auth := XOAuth2Auth("user", "token")
+		client, err := Dial(fmt.Sprintf("%s:%d", TestServerAddr, serverPort))
+		if err != nil {
+			t.Fatalf("failed to connect to test server: %s", err)
+		}
+		if err = client.Auth(auth); err == nil {
+			t.Errorf("expected authentication to fail")
+		}
+	})
 }
 
 /*