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authorRuss Cox <rsc@golang.org>2014-09-08 00:08:51 -0400
committerRuss Cox <rsc@golang.org>2014-09-08 00:08:51 -0400
commitc007ce824d9a4fccb148f9204e04c23ed2984b71 (patch)
tree7dcac257114ef5c446be5b7b68c27dea230b7c09 /src/container
parent220a6de47eced55956eb8af8d643d4f5b67fd634 (diff)
downloadgo-c007ce824d9a4fccb148f9204e04c23ed2984b71.tar.gz
go-c007ce824d9a4fccb148f9204e04c23ed2984b71.zip
build: move package sources from src/pkg to src
Preparation was in CL 134570043. This CL contains only the effect of 'hg mv src/pkg/* src'. For more about the move, see golang.org/s/go14nopkg.
Diffstat (limited to 'src/container')
-rw-r--r--src/container/heap/example_intheap_test.go47
-rw-r--r--src/container/heap/example_pq_test.go97
-rw-r--r--src/container/heap/heap.go117
-rw-r--r--src/container/heap/heap_test.go213
-rw-r--r--src/container/list/example_test.go30
-rw-r--r--src/container/list/list.go216
-rw-r--r--src/container/list/list_test.go343
-rw-r--r--src/container/ring/ring.go141
-rw-r--r--src/container/ring/ring_test.go228
9 files changed, 1432 insertions, 0 deletions
diff --git a/src/container/heap/example_intheap_test.go b/src/container/heap/example_intheap_test.go
new file mode 100644
index 0000000000..02d3d8668e
--- /dev/null
+++ b/src/container/heap/example_intheap_test.go
@@ -0,0 +1,47 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This example demonstrates an integer heap built using the heap interface.
+package heap_test
+
+import (
+ "container/heap"
+ "fmt"
+)
+
+// An IntHeap is a min-heap of ints.
+type IntHeap []int
+
+func (h IntHeap) Len() int { return len(h) }
+func (h IntHeap) Less(i, j int) bool { return h[i] < h[j] }
+func (h IntHeap) Swap(i, j int) { h[i], h[j] = h[j], h[i] }
+
+func (h *IntHeap) Push(x interface{}) {
+ // Push and Pop use pointer receivers because they modify the slice's length,
+ // not just its contents.
+ *h = append(*h, x.(int))
+}
+
+func (h *IntHeap) Pop() interface{} {
+ old := *h
+ n := len(old)
+ x := old[n-1]
+ *h = old[0 : n-1]
+ return x
+}
+
+// This example inserts several ints into an IntHeap, checks the minimum,
+// and removes them in order of priority.
+func Example_intHeap() {
+ h := &IntHeap{2, 1, 5}
+ heap.Init(h)
+ heap.Push(h, 3)
+ fmt.Printf("minimum: %d\n", (*h)[0])
+ for h.Len() > 0 {
+ fmt.Printf("%d ", heap.Pop(h))
+ }
+ // Output:
+ // minimum: 1
+ // 1 2 3 5
+}
diff --git a/src/container/heap/example_pq_test.go b/src/container/heap/example_pq_test.go
new file mode 100644
index 0000000000..7017095cb8
--- /dev/null
+++ b/src/container/heap/example_pq_test.go
@@ -0,0 +1,97 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This example demonstrates a priority queue built using the heap interface.
+package heap_test
+
+import (
+ "container/heap"
+ "fmt"
+)
+
+// An Item is something we manage in a priority queue.
+type Item struct {
+ value string // The value of the item; arbitrary.
+ priority int // The priority of the item in the queue.
+ // The index is needed by update and is maintained by the heap.Interface methods.
+ index int // The index of the item in the heap.
+}
+
+// A PriorityQueue implements heap.Interface and holds Items.
+type PriorityQueue []*Item
+
+func (pq PriorityQueue) Len() int { return len(pq) }
+
+func (pq PriorityQueue) Less(i, j int) bool {
+ // We want Pop to give us the highest, not lowest, priority so we use greater than here.
+ return pq[i].priority > pq[j].priority
+}
+
+func (pq PriorityQueue) Swap(i, j int) {
+ pq[i], pq[j] = pq[j], pq[i]
+ pq[i].index = i
+ pq[j].index = j
+}
+
+func (pq *PriorityQueue) Push(x interface{}) {
+ n := len(*pq)
+ item := x.(*Item)
+ item.index = n
+ *pq = append(*pq, item)
+}
+
+func (pq *PriorityQueue) Pop() interface{} {
+ old := *pq
+ n := len(old)
+ item := old[n-1]
+ item.index = -1 // for safety
+ *pq = old[0 : n-1]
+ return item
+}
+
+// update modifies the priority and value of an Item in the queue.
+func (pq *PriorityQueue) update(item *Item, value string, priority int) {
+ item.value = value
+ item.priority = priority
+ heap.Fix(pq, item.index)
+}
+
+// This example creates a PriorityQueue with some items, adds and manipulates an item,
+// and then removes the items in priority order.
+func Example_priorityQueue() {
+ // Some items and their priorities.
+ items := map[string]int{
+ "banana": 3, "apple": 2, "pear": 4,
+ }
+
+ // Create a priority queue, put the items in it, and
+ // establish the priority queue (heap) invariants.
+ pq := make(PriorityQueue, len(items))
+ i := 0
+ for value, priority := range items {
+ pq[i] = &Item{
+ value: value,
+ priority: priority,
+ index: i,
+ }
+ i++
+ }
+ heap.Init(&pq)
+
+ // Insert a new item and then modify its priority.
+ item := &Item{
+ value: "orange",
+ priority: 1,
+ }
+ heap.Push(&pq, item)
+ pq.update(item, item.value, 5)
+
+ // Take the items out; they arrive in decreasing priority order.
+ for pq.Len() > 0 {
+ item := heap.Pop(&pq).(*Item)
+ fmt.Printf("%.2d:%s ", item.priority, item.value)
+ }
+ // Output:
+ // 05:orange 04:pear 03:banana 02:apple
+}
diff --git a/src/container/heap/heap.go b/src/container/heap/heap.go
new file mode 100644
index 0000000000..c467a11910
--- /dev/null
+++ b/src/container/heap/heap.go
@@ -0,0 +1,117 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package heap provides heap operations for any type that implements
+// heap.Interface. A heap is a tree with the property that each node is the
+// minimum-valued node in its subtree.
+//
+// The minimum element in the tree is the root, at index 0.
+//
+// A heap is a common way to implement a priority queue. To build a priority
+// queue, implement the Heap interface with the (negative) priority as the
+// ordering for the Less method, so Push adds items while Pop removes the
+// highest-priority item from the queue. The Examples include such an
+// implementation; the file example_pq_test.go has the complete source.
+//
+package heap
+
+import "sort"
+
+// Any type that implements heap.Interface may be used as a
+// min-heap with the following invariants (established after
+// Init has been called or if the data is empty or sorted):
+//
+// !h.Less(j, i) for 0 <= i < h.Len() and 2*i+1 <= j <= 2*i+2 and j < h.Len()
+//
+// Note that Push and Pop in this interface are for package heap's
+// implementation to call. To add and remove things from the heap,
+// use heap.Push and heap.Pop.
+type Interface interface {
+ sort.Interface
+ Push(x interface{}) // add x as element Len()
+ Pop() interface{} // remove and return element Len() - 1.
+}
+
+// A heap must be initialized before any of the heap operations
+// can be used. Init is idempotent with respect to the heap invariants
+// and may be called whenever the heap invariants may have been invalidated.
+// Its complexity is O(n) where n = h.Len().
+//
+func Init(h Interface) {
+ // heapify
+ n := h.Len()
+ for i := n/2 - 1; i >= 0; i-- {
+ down(h, i, n)
+ }
+}
+
+// Push pushes the element x onto the heap. The complexity is
+// O(log(n)) where n = h.Len().
+//
+func Push(h Interface, x interface{}) {
+ h.Push(x)
+ up(h, h.Len()-1)
+}
+
+// Pop removes the minimum element (according to Less) from the heap
+// and returns it. The complexity is O(log(n)) where n = h.Len().
+// It is equivalent to Remove(h, 0).
+//
+func Pop(h Interface) interface{} {
+ n := h.Len() - 1
+ h.Swap(0, n)
+ down(h, 0, n)
+ return h.Pop()
+}
+
+// Remove removes the element at index i from the heap.
+// The complexity is O(log(n)) where n = h.Len().
+//
+func Remove(h Interface, i int) interface{} {
+ n := h.Len() - 1
+ if n != i {
+ h.Swap(i, n)
+ down(h, i, n)
+ up(h, i)
+ }
+ return h.Pop()
+}
+
+// Fix re-establishes the heap ordering after the element at index i has changed its value.
+// Changing the value of the element at index i and then calling Fix is equivalent to,
+// but less expensive than, calling Remove(h, i) followed by a Push of the new value.
+// The complexity is O(log(n)) where n = h.Len().
+func Fix(h Interface, i int) {
+ down(h, i, h.Len())
+ up(h, i)
+}
+
+func up(h Interface, j int) {
+ for {
+ i := (j - 1) / 2 // parent
+ if i == j || !h.Less(j, i) {
+ break
+ }
+ h.Swap(i, j)
+ j = i
+ }
+}
+
+func down(h Interface, i, n int) {
+ for {
+ j1 := 2*i + 1
+ if j1 >= n || j1 < 0 { // j1 < 0 after int overflow
+ break
+ }
+ j := j1 // left child
+ if j2 := j1 + 1; j2 < n && !h.Less(j1, j2) {
+ j = j2 // = 2*i + 2 // right child
+ }
+ if !h.Less(j, i) {
+ break
+ }
+ h.Swap(i, j)
+ i = j
+ }
+}
diff --git a/src/container/heap/heap_test.go b/src/container/heap/heap_test.go
new file mode 100644
index 0000000000..b3d054c5f3
--- /dev/null
+++ b/src/container/heap/heap_test.go
@@ -0,0 +1,213 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package heap
+
+import (
+ "math/rand"
+ "testing"
+)
+
+type myHeap []int
+
+func (h *myHeap) Less(i, j int) bool {
+ return (*h)[i] < (*h)[j]
+}
+
+func (h *myHeap) Swap(i, j int) {
+ (*h)[i], (*h)[j] = (*h)[j], (*h)[i]
+}
+
+func (h *myHeap) Len() int {
+ return len(*h)
+}
+
+func (h *myHeap) Pop() (v interface{}) {
+ *h, v = (*h)[:h.Len()-1], (*h)[h.Len()-1]
+ return
+}
+
+func (h *myHeap) Push(v interface{}) {
+ *h = append(*h, v.(int))
+}
+
+func (h myHeap) verify(t *testing.T, i int) {
+ n := h.Len()
+ j1 := 2*i + 1
+ j2 := 2*i + 2
+ if j1 < n {
+ if h.Less(j1, i) {
+ t.Errorf("heap invariant invalidated [%d] = %d > [%d] = %d", i, h[i], j1, h[j1])
+ return
+ }
+ h.verify(t, j1)
+ }
+ if j2 < n {
+ if h.Less(j2, i) {
+ t.Errorf("heap invariant invalidated [%d] = %d > [%d] = %d", i, h[i], j1, h[j2])
+ return
+ }
+ h.verify(t, j2)
+ }
+}
+
+func TestInit0(t *testing.T) {
+ h := new(myHeap)
+ for i := 20; i > 0; i-- {
+ h.Push(0) // all elements are the same
+ }
+ Init(h)
+ h.verify(t, 0)
+
+ for i := 1; h.Len() > 0; i++ {
+ x := Pop(h).(int)
+ h.verify(t, 0)
+ if x != 0 {
+ t.Errorf("%d.th pop got %d; want %d", i, x, 0)
+ }
+ }
+}
+
+func TestInit1(t *testing.T) {
+ h := new(myHeap)
+ for i := 20; i > 0; i-- {
+ h.Push(i) // all elements are different
+ }
+ Init(h)
+ h.verify(t, 0)
+
+ for i := 1; h.Len() > 0; i++ {
+ x := Pop(h).(int)
+ h.verify(t, 0)
+ if x != i {
+ t.Errorf("%d.th pop got %d; want %d", i, x, i)
+ }
+ }
+}
+
+func Test(t *testing.T) {
+ h := new(myHeap)
+ h.verify(t, 0)
+
+ for i := 20; i > 10; i-- {
+ h.Push(i)
+ }
+ Init(h)
+ h.verify(t, 0)
+
+ for i := 10; i > 0; i-- {
+ Push(h, i)
+ h.verify(t, 0)
+ }
+
+ for i := 1; h.Len() > 0; i++ {
+ x := Pop(h).(int)
+ if i < 20 {
+ Push(h, 20+i)
+ }
+ h.verify(t, 0)
+ if x != i {
+ t.Errorf("%d.th pop got %d; want %d", i, x, i)
+ }
+ }
+}
+
+func TestRemove0(t *testing.T) {
+ h := new(myHeap)
+ for i := 0; i < 10; i++ {
+ h.Push(i)
+ }
+ h.verify(t, 0)
+
+ for h.Len() > 0 {
+ i := h.Len() - 1
+ x := Remove(h, i).(int)
+ if x != i {
+ t.Errorf("Remove(%d) got %d; want %d", i, x, i)
+ }
+ h.verify(t, 0)
+ }
+}
+
+func TestRemove1(t *testing.T) {
+ h := new(myHeap)
+ for i := 0; i < 10; i++ {
+ h.Push(i)
+ }
+ h.verify(t, 0)
+
+ for i := 0; h.Len() > 0; i++ {
+ x := Remove(h, 0).(int)
+ if x != i {
+ t.Errorf("Remove(0) got %d; want %d", x, i)
+ }
+ h.verify(t, 0)
+ }
+}
+
+func TestRemove2(t *testing.T) {
+ N := 10
+
+ h := new(myHeap)
+ for i := 0; i < N; i++ {
+ h.Push(i)
+ }
+ h.verify(t, 0)
+
+ m := make(map[int]bool)
+ for h.Len() > 0 {
+ m[Remove(h, (h.Len()-1)/2).(int)] = true
+ h.verify(t, 0)
+ }
+
+ if len(m) != N {
+ t.Errorf("len(m) = %d; want %d", len(m), N)
+ }
+ for i := 0; i < len(m); i++ {
+ if !m[i] {
+ t.Errorf("m[%d] doesn't exist", i)
+ }
+ }
+}
+
+func BenchmarkDup(b *testing.B) {
+ const n = 10000
+ h := make(myHeap, n)
+ for i := 0; i < b.N; i++ {
+ for j := 0; j < n; j++ {
+ Push(&h, 0) // all elements are the same
+ }
+ for h.Len() > 0 {
+ Pop(&h)
+ }
+ }
+}
+
+func TestFix(t *testing.T) {
+ h := new(myHeap)
+ h.verify(t, 0)
+
+ for i := 200; i > 0; i -= 10 {
+ Push(h, i)
+ }
+ h.verify(t, 0)
+
+ if (*h)[0] != 10 {
+ t.Fatalf("Expected head to be 10, was %d", (*h)[0])
+ }
+ (*h)[0] = 210
+ Fix(h, 0)
+ h.verify(t, 0)
+
+ for i := 100; i > 0; i-- {
+ elem := rand.Intn(h.Len())
+ if i&1 == 0 {
+ (*h)[elem] *= 2
+ } else {
+ (*h)[elem] /= 2
+ }
+ Fix(h, elem)
+ h.verify(t, 0)
+ }
+}
diff --git a/src/container/list/example_test.go b/src/container/list/example_test.go
new file mode 100644
index 0000000000..3621784017
--- /dev/null
+++ b/src/container/list/example_test.go
@@ -0,0 +1,30 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package list_test
+
+import (
+ "container/list"
+ "fmt"
+)
+
+func Example() {
+ // Create a new list and put some numbers in it.
+ l := list.New()
+ e4 := l.PushBack(4)
+ e1 := l.PushFront(1)
+ l.InsertBefore(3, e4)
+ l.InsertAfter(2, e1)
+
+ // Iterate through list and print its contents.
+ for e := l.Front(); e != nil; e = e.Next() {
+ fmt.Println(e.Value)
+ }
+
+ // Output:
+ // 1
+ // 2
+ // 3
+ // 4
+}
diff --git a/src/container/list/list.go b/src/container/list/list.go
new file mode 100644
index 0000000000..0256768efe
--- /dev/null
+++ b/src/container/list/list.go
@@ -0,0 +1,216 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package list implements a doubly linked list.
+//
+// To iterate over a list (where l is a *List):
+// for e := l.Front(); e != nil; e = e.Next() {
+// // do something with e.Value
+// }
+//
+package list
+
+// Element is an element of a linked list.
+type Element struct {
+ // Next and previous pointers in the doubly-linked list of elements.
+ // To simplify the implementation, internally a list l is implemented
+ // as a ring, such that &l.root is both the next element of the last
+ // list element (l.Back()) and the previous element of the first list
+ // element (l.Front()).
+ next, prev *Element
+
+ // The list to which this element belongs.
+ list *List
+
+ // The value stored with this element.
+ Value interface{}
+}
+
+// Next returns the next list element or nil.
+func (e *Element) Next() *Element {
+ if p := e.next; e.list != nil && p != &e.list.root {
+ return p
+ }
+ return nil
+}
+
+// Prev returns the previous list element or nil.
+func (e *Element) Prev() *Element {
+ if p := e.prev; e.list != nil && p != &e.list.root {
+ return p
+ }
+ return nil
+}
+
+// List represents a doubly linked list.
+// The zero value for List is an empty list ready to use.
+type List struct {
+ root Element // sentinel list element, only &root, root.prev, and root.next are used
+ len int // current list length excluding (this) sentinel element
+}
+
+// Init initializes or clears list l.
+func (l *List) Init() *List {
+ l.root.next = &l.root
+ l.root.prev = &l.root
+ l.len = 0
+ return l
+}
+
+// New returns an initialized list.
+func New() *List { return new(List).Init() }
+
+// Len returns the number of elements of list l.
+// The complexity is O(1).
+func (l *List) Len() int { return l.len }
+
+// Front returns the first element of list l or nil.
+func (l *List) Front() *Element {
+ if l.len == 0 {
+ return nil
+ }
+ return l.root.next
+}
+
+// Back returns the last element of list l or nil.
+func (l *List) Back() *Element {
+ if l.len == 0 {
+ return nil
+ }
+ return l.root.prev
+}
+
+// lazyInit lazily initializes a zero List value.
+func (l *List) lazyInit() {
+ if l.root.next == nil {
+ l.Init()
+ }
+}
+
+// insert inserts e after at, increments l.len, and returns e.
+func (l *List) insert(e, at *Element) *Element {
+ n := at.next
+ at.next = e
+ e.prev = at
+ e.next = n
+ n.prev = e
+ e.list = l
+ l.len++
+ return e
+}
+
+// insertValue is a convenience wrapper for insert(&Element{Value: v}, at).
+func (l *List) insertValue(v interface{}, at *Element) *Element {
+ return l.insert(&Element{Value: v}, at)
+}
+
+// remove removes e from its list, decrements l.len, and returns e.
+func (l *List) remove(e *Element) *Element {
+ e.prev.next = e.next
+ e.next.prev = e.prev
+ e.next = nil // avoid memory leaks
+ e.prev = nil // avoid memory leaks
+ e.list = nil
+ l.len--
+ return e
+}
+
+// Remove removes e from l if e is an element of list l.
+// It returns the element value e.Value.
+func (l *List) Remove(e *Element) interface{} {
+ if e.list == l {
+ // if e.list == l, l must have been initialized when e was inserted
+ // in l or l == nil (e is a zero Element) and l.remove will crash
+ l.remove(e)
+ }
+ return e.Value
+}
+
+// PushFront inserts a new element e with value v at the front of list l and returns e.
+func (l *List) PushFront(v interface{}) *Element {
+ l.lazyInit()
+ return l.insertValue(v, &l.root)
+}
+
+// PushBack inserts a new element e with value v at the back of list l and returns e.
+func (l *List) PushBack(v interface{}) *Element {
+ l.lazyInit()
+ return l.insertValue(v, l.root.prev)
+}
+
+// InsertBefore inserts a new element e with value v immediately before mark and returns e.
+// If mark is not an element of l, the list is not modified.
+func (l *List) InsertBefore(v interface{}, mark *Element) *Element {
+ if mark.list != l {
+ return nil
+ }
+ // see comment in List.Remove about initialization of l
+ return l.insertValue(v, mark.prev)
+}
+
+// InsertAfter inserts a new element e with value v immediately after mark and returns e.
+// If mark is not an element of l, the list is not modified.
+func (l *List) InsertAfter(v interface{}, mark *Element) *Element {
+ if mark.list != l {
+ return nil
+ }
+ // see comment in List.Remove about initialization of l
+ return l.insertValue(v, mark)
+}
+
+// MoveToFront moves element e to the front of list l.
+// If e is not an element of l, the list is not modified.
+func (l *List) MoveToFront(e *Element) {
+ if e.list != l || l.root.next == e {
+ return
+ }
+ // see comment in List.Remove about initialization of l
+ l.insert(l.remove(e), &l.root)
+}
+
+// MoveToBack moves element e to the back of list l.
+// If e is not an element of l, the list is not modified.
+func (l *List) MoveToBack(e *Element) {
+ if e.list != l || l.root.prev == e {
+ return
+ }
+ // see comment in List.Remove about initialization of l
+ l.insert(l.remove(e), l.root.prev)
+}
+
+// MoveBefore moves element e to its new position before mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+func (l *List) MoveBefore(e, mark *Element) {
+ if e.list != l || e == mark || mark.list != l {
+ return
+ }
+ l.insert(l.remove(e), mark.prev)
+}
+
+// MoveAfter moves element e to its new position after mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+func (l *List) MoveAfter(e, mark *Element) {
+ if e.list != l || e == mark || mark.list != l {
+ return
+ }
+ l.insert(l.remove(e), mark)
+}
+
+// PushBackList inserts a copy of an other list at the back of list l.
+// The lists l and other may be the same.
+func (l *List) PushBackList(other *List) {
+ l.lazyInit()
+ for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
+ l.insertValue(e.Value, l.root.prev)
+ }
+}
+
+// PushFrontList inserts a copy of an other list at the front of list l.
+// The lists l and other may be the same.
+func (l *List) PushFrontList(other *List) {
+ l.lazyInit()
+ for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {
+ l.insertValue(e.Value, &l.root)
+ }
+}
diff --git a/src/container/list/list_test.go b/src/container/list/list_test.go
new file mode 100644
index 0000000000..4d8bfc2bf0
--- /dev/null
+++ b/src/container/list/list_test.go
@@ -0,0 +1,343 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package list
+
+import "testing"
+
+func checkListLen(t *testing.T, l *List, len int) bool {
+ if n := l.Len(); n != len {
+ t.Errorf("l.Len() = %d, want %d", n, len)
+ return false
+ }
+ return true
+}
+
+func checkListPointers(t *testing.T, l *List, es []*Element) {
+ root := &l.root
+
+ if !checkListLen(t, l, len(es)) {
+ return
+ }
+
+ // zero length lists must be the zero value or properly initialized (sentinel circle)
+ if len(es) == 0 {
+ if l.root.next != nil && l.root.next != root || l.root.prev != nil && l.root.prev != root {
+ t.Errorf("l.root.next = %p, l.root.prev = %p; both should both be nil or %p", l.root.next, l.root.prev, root)
+ }
+ return
+ }
+ // len(es) > 0
+
+ // check internal and external prev/next connections
+ for i, e := range es {
+ prev := root
+ Prev := (*Element)(nil)
+ if i > 0 {
+ prev = es[i-1]
+ Prev = prev
+ }
+ if p := e.prev; p != prev {
+ t.Errorf("elt[%d](%p).prev = %p, want %p", i, e, p, prev)
+ }
+ if p := e.Prev(); p != Prev {
+ t.Errorf("elt[%d](%p).Prev() = %p, want %p", i, e, p, Prev)
+ }
+
+ next := root
+ Next := (*Element)(nil)
+ if i < len(es)-1 {
+ next = es[i+1]
+ Next = next
+ }
+ if n := e.next; n != next {
+ t.Errorf("elt[%d](%p).next = %p, want %p", i, e, n, next)
+ }
+ if n := e.Next(); n != Next {
+ t.Errorf("elt[%d](%p).Next() = %p, want %p", i, e, n, Next)
+ }
+ }
+}
+
+func TestList(t *testing.T) {
+ l := New()
+ checkListPointers(t, l, []*Element{})
+
+ // Single element list
+ e := l.PushFront("a")
+ checkListPointers(t, l, []*Element{e})
+ l.MoveToFront(e)
+ checkListPointers(t, l, []*Element{e})
+ l.MoveToBack(e)
+ checkListPointers(t, l, []*Element{e})
+ l.Remove(e)
+ checkListPointers(t, l, []*Element{})
+
+ // Bigger list
+ e2 := l.PushFront(2)
+ e1 := l.PushFront(1)
+ e3 := l.PushBack(3)
+ e4 := l.PushBack("banana")
+ checkListPointers(t, l, []*Element{e1, e2, e3, e4})
+
+ l.Remove(e2)
+ checkListPointers(t, l, []*Element{e1, e3, e4})
+
+ l.MoveToFront(e3) // move from middle
+ checkListPointers(t, l, []*Element{e3, e1, e4})
+
+ l.MoveToFront(e1)
+ l.MoveToBack(e3) // move from middle
+ checkListPointers(t, l, []*Element{e1, e4, e3})
+
+ l.MoveToFront(e3) // move from back
+ checkListPointers(t, l, []*Element{e3, e1, e4})
+ l.MoveToFront(e3) // should be no-op
+ checkListPointers(t, l, []*Element{e3, e1, e4})
+
+ l.MoveToBack(e3) // move from front
+ checkListPointers(t, l, []*Element{e1, e4, e3})
+ l.MoveToBack(e3) // should be no-op
+ checkListPointers(t, l, []*Element{e1, e4, e3})
+
+ e2 = l.InsertBefore(2, e1) // insert before front
+ checkListPointers(t, l, []*Element{e2, e1, e4, e3})
+ l.Remove(e2)
+ e2 = l.InsertBefore(2, e4) // insert before middle
+ checkListPointers(t, l, []*Element{e1, e2, e4, e3})
+ l.Remove(e2)
+ e2 = l.InsertBefore(2, e3) // insert before back
+ checkListPointers(t, l, []*Element{e1, e4, e2, e3})
+ l.Remove(e2)
+
+ e2 = l.InsertAfter(2, e1) // insert after front
+ checkListPointers(t, l, []*Element{e1, e2, e4, e3})
+ l.Remove(e2)
+ e2 = l.InsertAfter(2, e4) // insert after middle
+ checkListPointers(t, l, []*Element{e1, e4, e2, e3})
+ l.Remove(e2)
+ e2 = l.InsertAfter(2, e3) // insert after back
+ checkListPointers(t, l, []*Element{e1, e4, e3, e2})
+ l.Remove(e2)
+
+ // Check standard iteration.
+ sum := 0
+ for e := l.Front(); e != nil; e = e.Next() {
+ if i, ok := e.Value.(int); ok {
+ sum += i
+ }
+ }
+ if sum != 4 {
+ t.Errorf("sum over l = %d, want 4", sum)
+ }
+
+ // Clear all elements by iterating
+ var next *Element
+ for e := l.Front(); e != nil; e = next {
+ next = e.Next()
+ l.Remove(e)
+ }
+ checkListPointers(t, l, []*Element{})
+}
+
+func checkList(t *testing.T, l *List, es []interface{}) {
+ if !checkListLen(t, l, len(es)) {
+ return
+ }
+
+ i := 0
+ for e := l.Front(); e != nil; e = e.Next() {
+ le := e.Value.(int)
+ if le != es[i] {
+ t.Errorf("elt[%d].Value = %v, want %v", i, le, es[i])
+ }
+ i++
+ }
+}
+
+func TestExtending(t *testing.T) {
+ l1 := New()
+ l2 := New()
+
+ l1.PushBack(1)
+ l1.PushBack(2)
+ l1.PushBack(3)
+
+ l2.PushBack(4)
+ l2.PushBack(5)
+
+ l3 := New()
+ l3.PushBackList(l1)
+ checkList(t, l3, []interface{}{1, 2, 3})
+ l3.PushBackList(l2)
+ checkList(t, l3, []interface{}{1, 2, 3, 4, 5})
+
+ l3 = New()
+ l3.PushFrontList(l2)
+ checkList(t, l3, []interface{}{4, 5})
+ l3.PushFrontList(l1)
+ checkList(t, l3, []interface{}{1, 2, 3, 4, 5})
+
+ checkList(t, l1, []interface{}{1, 2, 3})
+ checkList(t, l2, []interface{}{4, 5})
+
+ l3 = New()
+ l3.PushBackList(l1)
+ checkList(t, l3, []interface{}{1, 2, 3})
+ l3.PushBackList(l3)
+ checkList(t, l3, []interface{}{1, 2, 3, 1, 2, 3})
+
+ l3 = New()
+ l3.PushFrontList(l1)
+ checkList(t, l3, []interface{}{1, 2, 3})
+ l3.PushFrontList(l3)
+ checkList(t, l3, []interface{}{1, 2, 3, 1, 2, 3})
+
+ l3 = New()
+ l1.PushBackList(l3)
+ checkList(t, l1, []interface{}{1, 2, 3})
+ l1.PushFrontList(l3)
+ checkList(t, l1, []interface{}{1, 2, 3})
+}
+
+func TestRemove(t *testing.T) {
+ l := New()
+ e1 := l.PushBack(1)
+ e2 := l.PushBack(2)
+ checkListPointers(t, l, []*Element{e1, e2})
+ e := l.Front()
+ l.Remove(e)
+ checkListPointers(t, l, []*Element{e2})
+ l.Remove(e)
+ checkListPointers(t, l, []*Element{e2})
+}
+
+func TestIssue4103(t *testing.T) {
+ l1 := New()
+ l1.PushBack(1)
+ l1.PushBack(2)
+
+ l2 := New()
+ l2.PushBack(3)
+ l2.PushBack(4)
+
+ e := l1.Front()
+ l2.Remove(e) // l2 should not change because e is not an element of l2
+ if n := l2.Len(); n != 2 {
+ t.Errorf("l2.Len() = %d, want 2", n)
+ }
+
+ l1.InsertBefore(8, e)
+ if n := l1.Len(); n != 3 {
+ t.Errorf("l1.Len() = %d, want 3", n)
+ }
+}
+
+func TestIssue6349(t *testing.T) {
+ l := New()
+ l.PushBack(1)
+ l.PushBack(2)
+
+ e := l.Front()
+ l.Remove(e)
+ if e.Value != 1 {
+ t.Errorf("e.value = %d, want 1", e.Value)
+ }
+ if e.Next() != nil {
+ t.Errorf("e.Next() != nil")
+ }
+ if e.Prev() != nil {
+ t.Errorf("e.Prev() != nil")
+ }
+}
+
+func TestMove(t *testing.T) {
+ l := New()
+ e1 := l.PushBack(1)
+ e2 := l.PushBack(2)
+ e3 := l.PushBack(3)
+ e4 := l.PushBack(4)
+
+ l.MoveAfter(e3, e3)
+ checkListPointers(t, l, []*Element{e1, e2, e3, e4})
+ l.MoveBefore(e2, e2)
+ checkListPointers(t, l, []*Element{e1, e2, e3, e4})
+
+ l.MoveAfter(e3, e2)
+ checkListPointers(t, l, []*Element{e1, e2, e3, e4})
+ l.MoveBefore(e2, e3)
+ checkListPointers(t, l, []*Element{e1, e2, e3, e4})
+
+ l.MoveBefore(e2, e4)
+ checkListPointers(t, l, []*Element{e1, e3, e2, e4})
+ e1, e2, e3, e4 = e1, e3, e2, e4
+
+ l.MoveBefore(e4, e1)
+ checkListPointers(t, l, []*Element{e4, e1, e2, e3})
+ e1, e2, e3, e4 = e4, e1, e2, e3
+
+ l.MoveAfter(e4, e1)
+ checkListPointers(t, l, []*Element{e1, e4, e2, e3})
+ e1, e2, e3, e4 = e1, e4, e2, e3
+
+ l.MoveAfter(e2, e3)
+ checkListPointers(t, l, []*Element{e1, e3, e2, e4})
+ e1, e2, e3, e4 = e1, e3, e2, e4
+}
+
+// Test PushFront, PushBack, PushFrontList, PushBackList with uninitialized List
+func TestZeroList(t *testing.T) {
+ var l1 = new(List)
+ l1.PushFront(1)
+ checkList(t, l1, []interface{}{1})
+
+ var l2 = new(List)
+ l2.PushBack(1)
+ checkList(t, l2, []interface{}{1})
+
+ var l3 = new(List)
+ l3.PushFrontList(l1)
+ checkList(t, l3, []interface{}{1})
+
+ var l4 = new(List)
+ l4.PushBackList(l2)
+ checkList(t, l4, []interface{}{1})
+}
+
+// Test that a list l is not modified when calling InsertBefore with a mark that is not an element of l.
+func TestInsertBeforeUnknownMark(t *testing.T) {
+ var l List
+ l.PushBack(1)
+ l.PushBack(2)
+ l.PushBack(3)
+ l.InsertBefore(1, new(Element))
+ checkList(t, &l, []interface{}{1, 2, 3})
+}
+
+// Test that a list l is not modified when calling InsertAfter with a mark that is not an element of l.
+func TestInsertAfterUnknownMark(t *testing.T) {
+ var l List
+ l.PushBack(1)
+ l.PushBack(2)
+ l.PushBack(3)
+ l.InsertAfter(1, new(Element))
+ checkList(t, &l, []interface{}{1, 2, 3})