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// Copyright 2015 Canonical Ltd.
// Licensed under the LGPLv3, see LICENCE file for details.
package deque_test
import (
"container/list"
"github.com/juju/testing"
jc "github.com/juju/testing/checkers"
"github.com/juju/utils/deque"
gc "gopkg.in/check.v1"
)
type suite struct {
testing.IsolationSuite
deque *deque.Deque
}
var _ = gc.Suite(&suite{})
const testLen = 1000
func (s *suite) SetUpTest(c *gc.C) {
s.deque = deque.New()
}
func (s *suite) TestInit(c *gc.C) {
s.checkEmpty(c)
}
func (s *suite) TestStackBack(c *gc.C) {
// Push many values on to the back.
for i := 0; i < testLen; i++ {
c.Assert(s.deque.Len(), gc.Equals, i)
s.deque.PushBack(i)
}
// Pop them all off from the back.
for i := testLen; i > 0; i-- {
c.Assert(s.deque.Len(), gc.Equals, i)
v, ok := s.deque.PopBack()
c.Assert(ok, jc.IsTrue)
c.Assert(v.(int), gc.Equals, i-1)
}
s.checkEmpty(c)
}
func (s *suite) TestStackFront(c *gc.C) {
// Push many values on to the front.
for i := 0; i < testLen; i++ {
c.Assert(s.deque.Len(), gc.Equals, i)
s.deque.PushFront(i)
}
// Pop them all off from the front.
for i := testLen; i > 0; i-- {
c.Assert(s.deque.Len(), gc.Equals, i)
v, ok := s.deque.PopFront()
c.Assert(ok, jc.IsTrue)
c.Assert(v.(int), gc.Equals, i-1)
}
s.checkEmpty(c)
}
func (s *suite) TestQueueFromFront(c *gc.C) {
// Push many values on to the back.
for i := 0; i < testLen; i++ {
s.deque.PushBack(i)
}
// Pop them all off the front.
for i := 0; i < testLen; i++ {
v, ok := s.deque.PopFront()
c.Assert(ok, jc.IsTrue)
c.Assert(v.(int), gc.Equals, i)
}
s.checkEmpty(c)
}
func (s *suite) TestQueueFromBack(c *gc.C) {
// Push many values on to the front.
for i := 0; i < testLen; i++ {
s.deque.PushFront(i)
}
// Pop them all off the back.
for i := 0; i < testLen; i++ {
v, ok := s.deque.PopBack()
c.Assert(ok, jc.IsTrue)
c.Assert(v.(int), gc.Equals, i)
}
s.checkEmpty(c)
}
func (s *suite) TestFrontBack(c *gc.C) {
// Populate from the front and back.
for i := 0; i < testLen; i++ {
c.Assert(s.deque.Len(), gc.Equals, i*2)
s.deque.PushFront(i)
s.deque.PushBack(i)
}
// Remove half the items from the front and back.
for i := testLen; i > testLen/2; i-- {
c.Assert(s.deque.Len(), gc.Equals, i*2)
vb, ok := s.deque.PopBack()
c.Assert(ok, jc.IsTrue)
c.Assert(vb.(int), gc.Equals, i-1)
vf, ok := s.deque.PopFront()
c.Assert(ok, jc.IsTrue)
c.Assert(vf.(int), gc.Equals, i-1)
}
// Expand out again.
for i := testLen / 2; i < testLen; i++ {
c.Assert(s.deque.Len(), gc.Equals, i*2)
s.deque.PushFront(i)
s.deque.PushBack(i)
}
// Consume all.
for i := testLen; i > 0; i-- {
c.Assert(s.deque.Len(), gc.Equals, i*2)
vb, ok := s.deque.PopBack()
c.Assert(ok, jc.IsTrue)
c.Assert(vb.(int), gc.Equals, i-1)
vf, ok := s.deque.PopFront()
c.Assert(ok, jc.IsTrue)
c.Assert(vf.(int), gc.Equals, i-1)
}
s.checkEmpty(c)
}
func (s *suite) TestMaxLenFront(c *gc.C) {
const max = 5
d := deque.NewWithMaxLen(max)
// Exceed the maximum length by 2
for i := 0; i < max+2; i++ {
d.PushFront(i)
}
// Observe the the first 2 items on the back were dropped.
v, ok := d.PopBack()
c.Assert(ok, jc.IsTrue)
c.Assert(v.(int), gc.Equals, 2)
}
func (s *suite) TestMaxLenBack(c *gc.C) {
const max = 5
d := deque.NewWithMaxLen(max)
// Exceed the maximum length by 3
for i := 0; i < max+3; i++ {
d.PushBack(i)
}
// Observe the the first 3 items on the front were dropped.
v, ok := d.PopFront()
c.Assert(ok, jc.IsTrue)
c.Assert(v.(int), gc.Equals, 3)
}
func (s *suite) TestBlockAllocation(c *gc.C) {
// This test confirms that the Deque allocates and deallocates
// blocks as expected.
for i := 0; i < testLen; i++ {
s.deque.PushFront(i)
s.deque.PushBack(i)
}
// 2000 items at a blockLen of 64:
// 31 full blocks + 1 partial front + 1 partial back = 33
c.Assert(deque.GetDequeBlocks(s.deque), gc.Equals, 33)
for i := 0; i < testLen; i++ {
s.deque.PopFront()
s.deque.PopBack()
}
// At empty there should be just 1 block.
c.Assert(deque.GetDequeBlocks(s.deque), gc.Equals, 1)
}
func (s *suite) checkEmpty(c *gc.C) {
c.Assert(s.deque.Len(), gc.Equals, 0)
_, ok := s.deque.PopFront()
c.Assert(ok, jc.IsFalse)
_, ok = s.deque.PopBack()
c.Assert(ok, jc.IsFalse)
}
func (s *suite) BenchmarkPushBackList(c *gc.C) {
l := list.New()
for i := 0; i < c.N; i++ {
l.PushBack(i)
}
}
func (s *suite) BenchmarkPushBackDeque(c *gc.C) {
d := deque.New()
for i := 0; i < c.N; i++ {
d.PushBack(i)
}
}
func (s *suite) BenchmarkPushFrontList(c *gc.C) {
l := list.New()
for i := 0; i < c.N; i++ {
l.PushFront(i)
}
}
func (s *suite) BenchmarkPushFrontDeque(c *gc.C) {
d := deque.New()
for i := 0; i < c.N; i++ {
d.PushFront(i)
}
}
func (s *suite) BenchmarkPushPopFrontList(c *gc.C) {
l := list.New()
for i := 0; i < c.N; i++ {
l.PushFront(i)
}
for i := 0; i < c.N; i++ {
elem := l.Front()
_ = elem.Value
l.Remove(elem)
}
}
func (s *suite) BenchmarkPushPopFrontDeque(c *gc.C) {
d := deque.New()
for i := 0; i < c.N; i++ {
d.PushFront(i)
}
for i := 0; i < c.N; i++ {
_, _ = d.PopFront()
}
}
func (s *suite) BenchmarkPushPopBackList(c *gc.C) {
l := list.New()
for i := 0; i < c.N; i++ {
l.PushBack(i)
}
for i := 0; i < c.N; i++ {
elem := l.Back()
_ = elem.Value
l.Remove(elem)
}
}
func (s *suite) BenchmarkPushPopBackDeque(c *gc.C) {
d := deque.New()
for i := 0; i < c.N; i++ {
d.PushBack(i)
}
for i := 0; i < c.N; i++ {
_, _ = d.PopBack()
}
}
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