update error message

x/mongo/driver/connstring/initial_dns_seedlist_discovery_prose_test.go

@@ -81,16 +81,20 @@ func TestInitialDNSSeedlistDiscoveryProse(t *testing.T) {
 			uri    string
 			labels int
 		}{
-			{"localhost", "mongodb+srv://localhost", 2},
-			{"mongo.local", "mongodb+srv://mongo.local", 3},
+			{"localhost", "mongodb+srv://localhost", 1},
+			{"mongo.local", "mongodb+srv://mongo.local", 2},
 		}
 		for _, c := range cases {
 			c := c
 			t.Run(c.uri, func(t *testing.T) {
 				t.Parallel()
 
 				_, err := newTestParser(c.record).parse(c.uri)
-				assert.ErrorContains(t, err, fmt.Sprintf("DNS name must contain at least %d labels", c.labels))
+				expected := fmt.Sprintf(
+					"Server record (%d levels) should have more domain levels than parent URI (%d levels)",
+					c.labels, c.labels,
+				)
+				assert.ErrorContains(t, err, expected)
 			})
 		}
 	})

x/mongo/driver/dns/dns.go

@@ -114,7 +114,7 @@ func validateSRVResult(recordFromSRV, inputHostName string) error {
 	separatedInputDomain := strings.Split(strings.ToLower(inputHostName), ".")
 	separatedRecord := strings.Split(strings.ToLower(recordFromSRV), ".")
 	if l := len(separatedInputDomain); l < 3 && len(separatedRecord) <= l {
-		return fmt.Errorf("DNS name must contain at least %d labels", l+1)
+		return fmt.Errorf("Server record (%d levels) should have more domain levels than parent URI (%d levels)", l, len(separatedRecord))
 	}
 	if len(separatedRecord) < len(separatedInputDomain) {
 		return errors.New("Domain suffix from SRV record not matched input domain")