bc518174
 王天杨
提交两个项目文件
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
import { union, without } from './utils/js_utils.js'
type NodePredicate = (node: Node | null | undefined) => boolean
export class EnterLeaveCounter {
private entered: any[] = []
private isNodeInDocument: NodePredicate
public constructor(isNodeInDocument: NodePredicate) {
this.isNodeInDocument = isNodeInDocument
}
public enter(enteringNode: EventTarget | null): boolean {
const previousLength = this.entered.length
const isNodeEntered = (node: Node): boolean =>
this.isNodeInDocument(node) &&
(!node.contains || node.contains(enteringNode as Node))
this.entered = union(this.entered.filter(isNodeEntered), [enteringNode])
return previousLength === 0 && this.entered.length > 0
}
public leave(leavingNode: EventTarget | null): boolean {
const previousLength = this.entered.length
this.entered = without(
this.entered.filter(this.isNodeInDocument),
leavingNode,
)
return previousLength > 0 && this.entered.length === 0
}
public reset(): void {
this.entered = []
}
}
|
