test.js

import Relay from 'react-relay'

export default class ClickButtonMutation extends Relay.Mutation {
  static fragments = {
    viewer: () => Relay.QL`
      fragment on User {
        id
        buttonClicked
      }
    `,
  };
  getMutation() {
    return Relay.QL`mutation{clickButton}`;
  }
  getFatQuery() {
    return Relay.QL`
      fragment on ClickButtonPayload {
        viewer {
          buttonClicked
        }
      }
    `;
  }
  getConfigs() {
    return [{
      type: 'FIELDS_CHANGE',
      fieldIDs: {
        viewer: this.props.viewer.id
      }
    }];
  }
  getVariables() {
    return {
      buttonClicked: this.props.buttonClicked,
    };
  }
  getOptimisticResponse() {
    console.log('hi from optimistic')
    return {
      viewer: {
        id: this.props.viewer.id,
        buttonClicked: !this.props.viewer.buttonClicked
      },
    };
  }
}