getDefaultProps doesn't work with ES6 syntax; warning is not helpful

I’m trying to build a component that defines a default value for a required prop, but it doesn’t seem to work.

class ReviewsList extends Component {
  propTypes: {
    reviews : React.PropTypes.array.isRequired,
  }
  getDefaultProps() {
    return {
      reviews: [],
    };
  }
  render() {
    var reviewItems = this.props.reviews.map(function (review) {  // ERROR
      return (
        <RecipeReviewItem key={review.objectId} reviewText={review.reviewText}></RecipeReviewItem>
      )
    });

    return (
      <View>{reviewItems}</View>
    );
  }
}

When I run this, I get:

ERROR: undefined is not an object (evaluating 'this.props.reviews.map')

Why?

[seanfuture]

For future visitors, ES6 syntax for latest version should be ( none of the above ):

Revised

ReviewsList.propTypes = {
   reviews : React.PropTypes.array.isRequired,
}

ReviewsList.defaultProps = {
      reviews: [],
}

[ide]

defaultProps just needs to be a static property on the component class. How you want to do this is up to you.

Static property:

class C1 extends React.Component {
  static defaultProps = {
    prop: 'hello',
  };
}

Static getter:

class C2 extends React.Component {
  static get defaultProps() {
    return {
      prop: 'hello',
    };
  }
}

Assign a property:

class C3 extends React.Component {
}
C3.defaultProps = {
  prop: 'hello',
};