matchBool(t, true, l.V(4).Enabled())
			matchBool(t, true, l.V(6).Enabled())
		})
		mustMatchLength(t, 5, lines)
		mustRegexMatchString(t, lines[0], "0")
		mustRegexMatchString(t, lines[1], "1")
		mustRegexMatchString(t, lines[2], "2")
		mustRegexMatchString(t, lines[3], "3")
		mustRegexMatchString(t, lines[4], "4")
	})
}

func matchBool(t *testing.T, want bool, got bool) {
	t.Helper()
	if want != got {

		// s should be unmodified.
		s.Debug("Hello")

		_ = Sync()
	})
	if err != nil {
		t.Errorf("Got error '%v', expected success", err)
	}

	mustRegexMatchString(t, lines[0], `Hello	foo=override baz=123 qux=0.123`)
	mustRegexMatchString(t, lines[1], "Hello$")
}

func TestScopeJSON(t *testing.T) {
	const name = "TestScope"
	const desc = "Desc"
	s := RegisterScope(name, desc)

		WithLabels("foo", "bar").WithLabels("baz", 123, "qux", 0.123).Error("Hello")

		_ = Sync()
	})
	if err != nil {
		t.Errorf("Got error '%v', expected success", err)
	}

	mustRegexMatchString(t, lines[0], `Hello	foo=bar baz=123 qux=0.123`)
}

func TestLogWithTime(t *testing.T) {
	getLogTime := func(t *testing.T, line string) time.Time {
		type logEntry struct {
			Time time.Time `json:"time"`