Cycle de vie - React

MyTimer.js

import React from "react";

class MyTimer extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      timer: 0,
    };
  }

  componentDidMount() {
    console.log("le composant est monté");
    this.timerId = setInterval(() => this.tick(), 1000);
  }

  componentDidUpdate() {
    console.log("un update a eu lieu");
  }

  tick() {
    this.setState({
      timer: this.state.timer + 1,
    });
  }

  render() {
    return <div>My Timer : {this.state.timer}</div>;
  }
}

export default MyTimer;