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1/*
2 * Copyright 2020 Adobe. All rights reserved.
3 * This file is licensed to you under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License. You may obtain a copy
5 * of the License at http://www.apache.org/licenses/LICENSE-2.0
6 *
7 * Unless required by applicable law or agreed to in writing, software distributed under
8 * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
9 * OF ANY KIND, either express or implied. See the License for the specific language
10 * governing permissions and limitations under the License.
11 */
12
13import {EffectCallback, useEffect, useRef} from 'react';
14
15// Like useEffect, but only called for updates after the initial render.
16export function useUpdateEffect(effect: EffectCallback, dependencies: any[]): void {
17 const isInitialMount = useRef(true);
18 const lastDeps = useRef<any[] | null>(null);
19
20 useEffect(() => {
21 isInitialMount.current = true;
22 return () => {
23 isInitialMount.current = false;
24 };
25 }, []);
26
27 useEffect(() => {
28 let prevDeps = lastDeps.current;
29 if (isInitialMount.current) {
30 isInitialMount.current = false;
31 } else if (!prevDeps || dependencies.some((dep, i) => !Object.is(dep, prevDeps[i]))) {
32 effect();
33 }
34 lastDeps.current = dependencies;
35 // eslint-disable-next-line react-hooks/exhaustive-deps
36 }, dependencies);
37}