package mysql import ( "context" "net" "testing" "time" ) func TestConnectorReturnsTimeout(t *testing.T) { connector := &connector{&Config{ Net: "tcp", Addr: "1.1.1.1:1234", Timeout: 10 * time.Millisecond, }} _, err := connector.Connect(context.Background()) if err == nil { t.Fatal("error expected") } if nerr, ok := err.(*net.OpError); ok { expected := "dial tcp 1.1.1.1:1234: i/o timeout" if nerr.Error() != expected { t.Fatalf("expected %q, got %q", expected, nerr.Error()) } } else { t.Fatalf("expected %T, got %T", nerr, err) } }