Files
gf/container/gtree/gtree_redblacktree.go
Lance Add 13524a36bc fix(container): Add NilChecker Support to gmap, gset, and gtree for Typed Nil Issue Resolution (#4605)
## 描述
本PR为`gmap`、`gset`和`gtree`容器引入了`NilChecker`机制,以解决Go语言中的`typed
nil`问题。该实现允许用户注册自定义的nil检查函数来确定值是否应被视为nil,这对于处理那些会被存储到容器中的`typed
nil`值特别有用。
## 情况描述
当前`gmap`等容器的泛型容器存在对`value`的`nil`值无法正确过滤的问题,例如以下例子中如果使用默认的`if any(value)
!=
nil`去判断就会得到错误的结果,原因是会出现带有类型的`(*Student)(nil)`直接和`nil`比较或者使用`any`强转都是不对的,使用反射可以解决但是性能太差了,所以换个思虑我们让用户自己决定如何判断`nil`就能解决这个问题
```golang
func main() {
	type Student struct {
		Name string
		Age  int
	}
	m1 := gmap.NewKVMap[int, *Student](true)
	for i := 0; i < 10; i++ {
		m1.GetOrSetFuncLock(i, func() *Student {
			if i%2 == 0 {
				return &Student{}
			}
			return nil
		})
	}
	fmt.Println(m1.Size()) //  10
	m2 := gmap.NewKVMap[int, *Student](true)
	m2.RegisterNilChecker(func(student *Student) bool {
		return student == nil
	})
	for i := 0; i < 10; i++ {
		m2.GetOrSetFuncLock(i, func() *Student {
			if i%2 == 0 {
				return &Student{}
			}
			return nil
		})
	}
	fmt.Println(m2.Size())  // 5

}

```

## 变更内容
- 在gmap、gset和gtree包中添加了`NilChecker`类型定义
- 扩展容器结构体,增加`nilChecker`字段来存储自定义nil检查函数
- 实现了`RegisterNilChecker`方法,允许用户注册自定义nil检查逻辑
- 添加了`isNil`内部方法,优先使用自定义nil检查函数或回退到默认的`any(v) == nil`检查
- 更新关键操作(AddIfNotExist、Set等)以利用nil检查机制
- 为所有三个容器类型添加了全面的测试用例以验证nilchecker功能

---------

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
2026-01-15 10:18:05 +08:00

390 lines
13 KiB
Go

// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package gtree
import (
"sync"
"github.com/gogf/gf/v2/container/gvar"
"github.com/gogf/gf/v2/util/gutil"
)
var _ iTree = (*RedBlackTree)(nil)
// RedBlackTree holds elements of the red-black tree.
type RedBlackTree struct {
*RedBlackKVTree[any, any]
once sync.Once
}
// RedBlackTreeNode is a single element within the tree.
type RedBlackTreeNode = RedBlackKVTreeNode[any, any]
// NewRedBlackTree instantiates a red-black tree with the custom key comparator.
// The parameter `safe` is used to specify whether using tree in concurrent-safety,
// which is false in default.
func NewRedBlackTree(comparator func(v1, v2 any) int, safe ...bool) *RedBlackTree {
return &RedBlackTree{
RedBlackKVTree: NewRedBlackKVTree[any, any](comparator, safe...),
}
}
// NewRedBlackTreeFrom instantiates a red-black tree with the custom key comparator and `data` map.
// The parameter `safe` is used to specify whether using tree in concurrent-safety,
// which is false in default.
func NewRedBlackTreeFrom(comparator func(v1, v2 any) int, data map[any]any, safe ...bool) *RedBlackTree {
return &RedBlackTree{
RedBlackKVTree: NewRedBlackKVTreeFrom(comparator, data, safe...),
}
}
// lazyInit lazily initializes the tree.
func (tree *RedBlackTree) lazyInit() {
tree.once.Do(func() {
if tree.RedBlackKVTree == nil {
tree.RedBlackKVTree = NewRedBlackKVTree[any, any](gutil.ComparatorTStr[any], false)
}
})
}
// SetComparator sets/changes the comparator for sorting.
func (tree *RedBlackTree) SetComparator(comparator func(a, b any) int) {
tree.lazyInit()
tree.RedBlackKVTree.SetComparator(comparator)
}
// Clone clones and returns a new tree from current tree.
func (tree *RedBlackTree) Clone() *RedBlackTree {
if tree == nil {
return nil
}
tree.lazyInit()
return &RedBlackTree{
RedBlackKVTree: tree.RedBlackKVTree.Clone(),
}
}
// Set sets key-value pair into the tree.
func (tree *RedBlackTree) Set(key any, value any) {
tree.lazyInit()
tree.RedBlackKVTree.Set(key, value)
}
// Sets batch sets key-values to the tree.
func (tree *RedBlackTree) Sets(data map[any]any) {
tree.lazyInit()
tree.RedBlackKVTree.Sets(data)
}
// SetIfNotExist sets `value` to the map if the `key` does not exist, and then returns true.
// It returns false if `key` exists, and such setting key-value pair operation would be ignored.
func (tree *RedBlackTree) SetIfNotExist(key any, value any) bool {
tree.lazyInit()
return tree.RedBlackKVTree.SetIfNotExist(key, value)
}
// SetIfNotExistFunc sets value with return value of callback function `f`, and then returns true.
// It returns false if `key` exists, and such setting key-value pair operation would be ignored.
func (tree *RedBlackTree) SetIfNotExistFunc(key any, f func() any) bool {
tree.lazyInit()
return tree.RedBlackKVTree.SetIfNotExistFunc(key, f)
}
// SetIfNotExistFuncLock sets value with return value of callback function `f`, and then returns true.
// It returns false if `key` exists, and such setting key-value pair operation would be ignored.
//
// SetIfNotExistFuncLock differs with SetIfNotExistFunc function is that
// it executes function `f` within mutex lock.
func (tree *RedBlackTree) SetIfNotExistFuncLock(key any, f func() any) bool {
tree.lazyInit()
return tree.RedBlackKVTree.SetIfNotExistFuncLock(key, f)
}
// Get searches the `key` in the tree and returns its associated `value` or nil if key is not found in tree.
//
// Note that, the `nil` value from Get function cannot be used to determine key existence, please use Contains function
// to do so.
func (tree *RedBlackTree) Get(key any) (value any) {
tree.lazyInit()
return tree.RedBlackKVTree.Get(key)
}
// GetOrSet returns its `value` of `key`, or sets value with given `value` if it does not exist and then returns
// this value.
func (tree *RedBlackTree) GetOrSet(key any, value any) any {
tree.lazyInit()
return tree.RedBlackKVTree.GetOrSet(key, value)
}
// GetOrSetFunc returns its `value` of `key`, or sets value with returned value of callback function `f` if it does not
// exist and then returns this value.
func (tree *RedBlackTree) GetOrSetFunc(key any, f func() any) any {
tree.lazyInit()
return tree.RedBlackKVTree.GetOrSetFunc(key, f)
}
// GetOrSetFuncLock returns its `value` of `key`, or sets value with returned value of callback function `f` if it does
// not exist and then returns this value.
//
// GetOrSetFuncLock differs with GetOrSetFunc function is that it executes function `f`within mutex lock.
func (tree *RedBlackTree) GetOrSetFuncLock(key any, f func() any) any {
tree.lazyInit()
return tree.RedBlackKVTree.GetOrSetFuncLock(key, f)
}
// GetVar returns a gvar.Var with the value by given `key`.
// Note that, the returned gvar.Var is un-concurrent safe.
//
// Also see function Get.
func (tree *RedBlackTree) GetVar(key any) *gvar.Var {
tree.lazyInit()
return tree.RedBlackKVTree.GetVar(key)
}
// GetVarOrSet returns a gvar.Var with result from GetVarOrSet.
// Note that, the returned gvar.Var is un-concurrent safe.
//
// Also see function GetOrSet.
func (tree *RedBlackTree) GetVarOrSet(key any, value any) *gvar.Var {
tree.lazyInit()
return tree.RedBlackKVTree.GetVarOrSet(key, value)
}
// GetVarOrSetFunc returns a gvar.Var with result from GetOrSetFunc.
// Note that, the returned gvar.Var is un-concurrent safe.
//
// Also see function GetOrSetFunc.
func (tree *RedBlackTree) GetVarOrSetFunc(key any, f func() any) *gvar.Var {
tree.lazyInit()
return tree.RedBlackKVTree.GetVarOrSetFunc(key, f)
}
// GetVarOrSetFuncLock returns a gvar.Var with result from GetOrSetFuncLock.
// Note that, the returned gvar.Var is un-concurrent safe.
//
// Also see function GetOrSetFuncLock.
func (tree *RedBlackTree) GetVarOrSetFuncLock(key any, f func() any) *gvar.Var {
tree.lazyInit()
return tree.RedBlackKVTree.GetVarOrSetFuncLock(key, f)
}
// Search searches the tree with given `key`.
// Second return parameter `found` is true if key was found, otherwise false.
func (tree *RedBlackTree) Search(key any) (value any, found bool) {
tree.lazyInit()
return tree.RedBlackKVTree.Search(key)
}
// Contains checks and returns whether given `key` exists in the tree.
func (tree *RedBlackTree) Contains(key any) bool {
tree.lazyInit()
return tree.RedBlackKVTree.Contains(key)
}
// Size returns number of nodes in the tree.
func (tree *RedBlackTree) Size() int {
tree.lazyInit()
return tree.RedBlackKVTree.Size()
}
// IsEmpty returns true if tree does not contain any nodes.
func (tree *RedBlackTree) IsEmpty() bool {
tree.lazyInit()
return tree.RedBlackKVTree.IsEmpty()
}
// Remove removes the node from the tree by `key`, and returns its associated value of `key`.
// The given `key` should adhere to the comparator's type assertion, otherwise method panics.
func (tree *RedBlackTree) Remove(key any) (value any) {
tree.lazyInit()
return tree.RedBlackKVTree.Remove(key)
}
// Removes batch deletes key-value pairs from the tree by `keys`.
func (tree *RedBlackTree) Removes(keys []any) {
tree.lazyInit()
tree.RedBlackKVTree.Removes(keys)
}
// Clear removes all nodes from the tree.
func (tree *RedBlackTree) Clear() {
tree.lazyInit()
tree.RedBlackKVTree.Clear()
}
// Keys returns all keys from the tree in order by its comparator.
func (tree *RedBlackTree) Keys() []any {
tree.lazyInit()
return tree.RedBlackKVTree.Keys()
}
// Values returns all values from the true in order by its comparator based on the key.
func (tree *RedBlackTree) Values() []any {
tree.lazyInit()
return tree.RedBlackKVTree.Values()
}
// Replace clears the data of the tree and sets the nodes by given `data`.
func (tree *RedBlackTree) Replace(data map[any]any) {
tree.lazyInit()
tree.RedBlackKVTree.Replace(data)
}
// Print prints the tree to stdout.
func (tree *RedBlackTree) Print() {
tree.lazyInit()
tree.RedBlackKVTree.Print()
}
// String returns a string representation of container
func (tree *RedBlackTree) String() string {
tree.lazyInit()
return tree.RedBlackKVTree.String()
}
// MarshalJSON implements the interface MarshalJSON for json.Marshal.
func (tree RedBlackTree) MarshalJSON() (jsonBytes []byte, err error) {
tree.lazyInit()
return tree.RedBlackKVTree.MarshalJSON()
}
// Map returns all key-value pairs as map.
func (tree *RedBlackTree) Map() map[any]any {
tree.lazyInit()
return tree.RedBlackKVTree.Map()
}
// MapStrAny returns all key-value items as map[string]any.
func (tree *RedBlackTree) MapStrAny() map[string]any {
tree.lazyInit()
return tree.RedBlackKVTree.MapStrAny()
}
// Iterator is alias of IteratorAsc.
//
// Also see IteratorAsc.
func (tree *RedBlackTree) Iterator(f func(key, value any) bool) {
tree.lazyInit()
tree.RedBlackKVTree.Iterator(f)
}
// IteratorFrom is alias of IteratorAscFrom.
//
// Also see IteratorAscFrom.
func (tree *RedBlackTree) IteratorFrom(key any, match bool, f func(key, value any) bool) {
tree.lazyInit()
tree.RedBlackKVTree.IteratorFrom(key, match, f)
}
// IteratorAsc iterates the tree readonly in ascending order with given callback function `f`.
// If callback function `f` returns true, then it continues iterating; or false to stop.
func (tree *RedBlackTree) IteratorAsc(f func(key, value any) bool) {
tree.lazyInit()
tree.RedBlackKVTree.IteratorAsc(f)
}
// IteratorAscFrom iterates the tree readonly in ascending order with given callback function `f`.
//
// The parameter `key` specifies the start entry for iterating.
// The parameter `match` specifies whether starting iterating only if the `key` is fully matched, or else using index
// searching iterating.
// If callback function `f` returns true, then it continues iterating; or false to stop.
func (tree *RedBlackTree) IteratorAscFrom(key any, match bool, f func(key, value any) bool) {
tree.lazyInit()
tree.RedBlackKVTree.IteratorAscFrom(key, match, f)
}
// IteratorDesc iterates the tree readonly in descending order with given callback function `f`.
//
// If callback function `f` returns true, then it continues iterating; or false to stop.
func (tree *RedBlackTree) IteratorDesc(f func(key, value any) bool) {
tree.lazyInit()
tree.RedBlackKVTree.IteratorDesc(f)
}
// IteratorDescFrom iterates the tree readonly in descending order with given callback function `f`.
//
// The parameter `key` specifies the start entry for iterating.
// The parameter `match` specifies whether starting iterating only if the `key` is fully matched, or else using index
// searching iterating.
// If callback function `f` returns true, then it continues iterating; or false to stop.
func (tree *RedBlackTree) IteratorDescFrom(key any, match bool, f func(key, value any) bool) {
tree.lazyInit()
tree.RedBlackKVTree.IteratorDescFrom(key, match, f)
}
// Left returns the minimum element corresponding to the comparator of the tree or nil if the tree is empty.
func (tree *RedBlackTree) Left() *RedBlackTreeNode {
tree.lazyInit()
return tree.RedBlackKVTree.Left()
}
// Right returns the maximum element corresponding to the comparator of the tree or nil if the tree is empty.
func (tree *RedBlackTree) Right() *RedBlackTreeNode {
tree.lazyInit()
return tree.RedBlackKVTree.Right()
}
// Floor Finds floor node of the input key, returns the floor node or nil if no floor node is found.
// The second returned parameter `found` is true if floor was found, otherwise false.
//
// Floor node is defined as the largest node that is smaller than or equal to the given node.
// A floor node may not be found, either because the tree is empty, or because
// all nodes in the tree is larger than the given node.
//
// Key should adhere to the comparator's type assertion, otherwise method panics.
func (tree *RedBlackTree) Floor(key any) (floor *RedBlackTreeNode, found bool) {
tree.lazyInit()
return tree.RedBlackKVTree.Floor(key)
}
// Ceiling finds ceiling node of the input key, returns the ceiling node or nil if no ceiling node is found.
// The second return parameter `found` is true if ceiling was found, otherwise false.
//
// Ceiling node is defined as the smallest node that is larger than or equal to the given node.
// A ceiling node may not be found, either because the tree is empty, or because
// all nodes in the tree is smaller than the given node.
//
// Key should adhere to the comparator's type assertion, otherwise method panics.
func (tree *RedBlackTree) Ceiling(key any) (ceiling *RedBlackTreeNode, found bool) {
tree.lazyInit()
return tree.RedBlackKVTree.Ceiling(key)
}
// Flip exchanges key-value of the tree to value-key.
// Note that you should guarantee the value is the same type as key,
// or else the comparator would panic.
//
// If the type of value is different with key, you pass the new `comparator`.
func (tree *RedBlackTree) Flip(comparator ...func(v1, v2 any) int) {
tree.lazyInit()
var t = new(RedBlackTree)
if len(comparator) > 0 {
t = NewRedBlackTree(comparator[0], tree.mu.IsSafe())
} else {
t = NewRedBlackTree(tree.comparator, tree.mu.IsSafe())
}
tree.IteratorAsc(func(key, value any) bool {
t.doSet(value, key)
return true
})
tree.Clear()
tree.Sets(t.Map())
}
// UnmarshalJSON implements the interface UnmarshalJSON for json.Unmarshal.
func (tree *RedBlackTree) UnmarshalJSON(b []byte) error {
tree.lazyInit()
return tree.RedBlackKVTree.UnmarshalJSON(b)
}
// UnmarshalValue is an interface implement which sets any type of value for map.
func (tree *RedBlackTree) UnmarshalValue(value any) (err error) {
tree.lazyInit()
return tree.RedBlackKVTree.UnmarshalValue(value)
}