react/no-will-update-set-state

📝 Disallow usage of setState in componentWillUpdate.

Updating the state during the componentWillUpdate step can lead to indeterminate component state and is not allowed.

Rule Details

Examples of incorrect code for this rule:

var Hello = createReactClass({
  componentWillUpdate: function() {
     this.setState({
        name: this.props.name.toUpperCase()
      });
    },
  render: function() {
    return <div>Hello {this.state.name}</div>;
  }
});

Examples of correct code for this rule:

var Hello = createReactClass({
  componentWillUpdate: function() {
    this.props.prepareHandler();
  },
  render: function() {
    return <div>Hello {this.props.name}</div>;
  }
});

var Hello = createReactClass({
  componentWillUpdate: function() {
    this.prepareHandler(function callback(newName) {
      this.setState({
        name: newName
      });
    });
  },
  render: function() {
    return <div>Hello {this.props.name}</div>;
  }
});

Rule Options

...
"react/no-will-update-set-state": [<enabled>, <mode>]
...

disallow-in-func mode

By default this rule forbids any call to this.setState in componentWillUpdate outside of functions. The disallow-in-func mode makes this rule more strict by disallowing calls to this.setState even within functions.

Examples of incorrect code for this rule:

var Hello = createReactClass({
  componentWillUpdate: function() {
     this.setState({
        name: this.props.name.toUpperCase()
      });
    },
  render: function() {
    return <div>Hello {this.state.name}</div>;
  }
});

var Hello = createReactClass({
  componentWillUpdate: function() {
    this.prepareHandler(function callback(newName) {
      this.setState({
        name: newName
      });
    });
  },
  render: function() {
    return <div>Hello {this.state.name}</div>;
  }
});