feat: GetCb

cmap.go

@@ -144,6 +144,18 @@ func (m ConcurrentMap[K, V]) GetOrInsert(key K, cb InsertCb[V]) V {
 	return v
 }
 
+// GetCb is a callback executed in a map.GetCb() call, while Lock is held
+// If returns true, the element will be inserted into the map
+type GetCb[V any] func(value V, exists bool)
+
+// GetCb locks the shard containing the key, retrieves its current value and calls the callback with those params
+func (m ConcurrentMap[K, V]) GetCb(key K, cb GetCb[V]) {
+	// Get shard
+	shard := m.GetShard(key)
+	v, exist := shard.Get(key)
+	cb(v, exist)
+}
+
 // Count returns the number of elements within the map.
 func (m ConcurrentMap[K, V]) Count() int {
 	count := 0
@@ -171,7 +183,7 @@ func (m ConcurrentMap[K, V]) Remove(key K) {
 
 // RemoveCb is a callback executed in a map.RemoveCb() call, while Lock is held
 // If returns true, the element will be removed from the map
-type RemoveCb[K any, V any] func(key K, value V, exists bool) bool
+type RemoveCb[K any, V any] func(value V, exists bool) bool
 
 // RemoveCb locks the shard containing the key, retrieves its current value and calls the callback with those params
 // If callback returns true and element exists, it will remove it from the map
@@ -181,7 +193,7 @@ func (m ConcurrentMap[K, V]) RemoveCb(key K, cb RemoveCb[K, V]) (ok bool) {
 	shard := m.GetShard(key)
 	shard.Update(func(m map[K]V) {
 		v, exist := m[key]
-		result := cb(key, v, exist)
+		result := cb(v, exist)
 		ok = exist && result
 		if ok {
 			delete(m, key)

cmap_test.go

@@ -127,12 +127,10 @@ func TestRemoveCb(t *testing.T) {
 	m.Set("elephant", elephant)
 
 	var (
-		mapKey   string
 		mapVal   Animal
 		wasFound bool
 	)
-	cb := func(key string, val Animal, exists bool) bool {
-		mapKey = key
+	cb := func(val Animal, exists bool) bool {
 		mapVal = val
 		wasFound = exists
 
@@ -145,10 +143,6 @@ func TestRemoveCb(t *testing.T) {
 		t.Errorf("Result was not true")
 	}
 
-	if mapKey != "monkey" {
-		t.Error("Wrong key was provided to the callback")
-	}
-
 	if mapVal != monkey {
 		t.Errorf("Wrong value was provided to the value")
 	}
@@ -167,10 +161,6 @@ func TestRemoveCb(t *testing.T) {
 		t.Errorf("Result was true")
 	}
 
-	if mapKey != "elephant" {
-		t.Error("Wrong key was provided to the callback")
-	}
-
 	if mapVal != elephant {
 		t.Errorf("Wrong value was provided to the value")
 	}
@@ -189,10 +179,6 @@ func TestRemoveCb(t *testing.T) {
 		t.Errorf("Result was true")
 	}
 
-	if mapKey != "horse" {
-		t.Error("Wrong key was provided to the callback")
-	}
-
 	if (mapVal != Animal{}) {
 		t.Errorf("Wrong value was provided to the value")
 	}
@@ -672,3 +658,40 @@ func TestGetOrInsert(t *testing.T) {
 		})
 	}
 }
+
+func TestGetCb(t *testing.T) {
+	// 初始化一个ConcurrentMap
+	m := New[string]()
+
+	// 定义测试用例
+	tests := []struct {
+		name      string
+		key       string
+		value     string
+		wantValue string
+	}{
+		{"v1", "key1", "value1", "value1"},
+		{"v2", "key2", "value2", "value2"},
+		{"v3", "key3", "value3", "value3"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// 在map中设置键值对
+			m.Set(tt.key, tt.value)
+
+			// 定义回调函数
+			cb := func(v string, exist bool) {
+				if !exist {
+					t.Errorf("GetCb(%s) not exist", tt.key)
+				}
+				if v != tt.value {
+					t.Errorf("GetCb() v = %v, wantValue = %v", v, tt.value)
+				}
+			}
+
+			// 调用待测函数
+			m.GetCb(tt.key, cb)
+		})
+	}
+}