fail fast when rolling window size is zero

core/collection/rollingwindow.go

@@ -22,6 +22,10 @@ type (
 )
 
 func NewRollingWindow(size int, interval time.Duration, opts ...RollingWindowOption) *RollingWindow {
+	if size < 1 {
+		panic("size must be greater than 0")
+	}
+
 	w := &RollingWindow{
 		size:     size,
 		win:      newWindow(size),

core/collection/rollingwindow_test.go

@@ -11,6 +11,13 @@ import (
 
 const duration = time.Millisecond * 50
 
+func TestNewRollingWindow(t *testing.T) {
+	assert.NotNil(t, NewRollingWindow(10, time.Second))
+	assert.Panics(t, func() {
+		NewRollingWindow(0, time.Second)
+	})
+}
+
 func TestRollingWindowAdd(t *testing.T) {
 	const size = 3
 	r := NewRollingWindow(size, duration)