@atlaskit/editor-common/dist/cjs/hooks/usePreviousState.js

A package that contains common classes and components for editor and renderer

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = usePreviousState;
var _react = require("react");
/**
 *
 * Can be used to get the previous state of a prop.
 * This can be helpful when converting class components to functional
 * where we don't have the `prevProps`.
 *
 * @param value New state of the
 * @param initialValue Optional parameter for the inital state of the component
 * @returns
 */
function usePreviousState(value, initialValue) {
  var ref = (0, _react.useRef)(initialValue);
  (0, _react.useEffect)(function () {
    // Setting the value to ref.current inside an effect, or otherwise the behaviour in staging/prod doesn't match with local
    // In local, the double rendering in react dev mode causes the previous value to be the same as next value immediately after
    // In prod and staging, double rendering is not done since that is a react prod build
    ref.current = value;
  }, [value]);
  return ref.current;
}