no-direct-mutation-state.md

Prevent direct mutation of this.state (react/no-direct-mutation-state)

NEVER mutate this.state directly, as calling setState() afterwards may replace the mutation you made. Treat this.state as if it were immutable.

Rule Details

This rule is aimed to forbid the use of mutating this.state directly.

The following patterns are considered warnings:

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

The following patterns are not considered warnings:

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