react warning computedMatch regarding some case issues?

I had this issue with react-router-dom because I placed a div inside my Switch. Instead, I moved my div outside of my Switch and the error is gone.


From React doc

The unknown-prop warning will fire if you attempt to render a DOM element with a prop that is not recognized by React as a legal DOM attribute/property. You should ensure that your DOM elements do not have spurious props floating around.

Inside the <Switch> component, you will see the below line.

React.cloneElement(child, { location, computedMatch: match })

In this case, the child is your <div></div>, so a non standard props computedMatch are being passed to native dom node <div>, thus React gives you an healthy warning. So, using <> or <Fragment> will discard the warning.


I solve that issue remove <div> tag inside the tag. or replace <div> with <React.Fragment>.

in this case :

import React,{Component} from "react";
import {BrowserRouter as Router, Switch, Route} from "react-router-dom";
import LogoutHome from './Logout_Home';
import SignIn from '../Components/SignIn';
import jwt_decode from 'jwt-decode';
import {setCurrentUser} from '../actions/authActions';
import SignUp from '../Components/SignUp';
import setAuthToken from '../util/setAuthToken';
import AboutUs from '../containers/AboutUs';
import store from '../store';
import {connect} from "react-redux";
// check for TOKEN
if (localStorage.jwtToken) {
  // Set auth token header auth
  setAuthToken(localStorage.jwtToken);
  // Decode token and get user info and exp
  const decoded = jwt_decode(localStorage.jwtToken);
  // Set user and isAuthenticated
  store.dispatch(setCurrentUser(decoded));

  // Check for expired token
  const currentTime = Date.now() / 1000;
  if (decoded.exp < currentTime) {
    // Logout user
    store.dispatch(logoutUser());

    // Redirect to login
    window.location.href = '/login';
  }
}
class HomePage extends Component
{
  componentDidMount(){
    console.log(this.props.auth.isAuthenticated);
  }
    render(){
      var {
        isAuthenticated
      } = this.props.auth;
      return(
        <div>
          <Router>
            <div>
              <Switch>
                {this.props.auth.isAuthenticated===false ? (
                  <React.Fragment>
                  <Route exact path='/' component={LogoutHome}/>
                  <Route  path='/Finance/Login' component={SignIn}/>
                  <Route  path='/Finance/AboutUs' component={AboutUs}/>
                  <Route  path='/Finance/ContactUs' component={ContactUs}/>
                  <Route  path='/Finance/SignUp' component={SignUp}/>
                  <Route  path='/Finance/Forgotpassword' component={Forgotpassword}/>
                  </React.Fragment>
                  ) : (
                    <React.Fragment>
                  <Route  path='/Finance/Home' component={Home}/>
                  </React.Fragment>
                  )}
              </Switch>
            </div>
          </Router>
        </div>
      );
    }
}
function mapStateToProps(state){
  return{
    auth : state.auth
  };
}
export default connect(mapStateToProps)(HomePage);

As others have said, the issue comes from having a <div> directly inside of a <Switch> element. From the documentation for <Switch>:

All children of a <Switch> should be <Route> or <Redirect> elements.

So while you apparently can get rid of this error by wrapping your element in a fragment tag, it's more in-line with the intended usage to wrap it in a <Route> element instead.

A <Route> with no props should provide the intended behavior.