test.js

class extends React.Component {
  componentDidMount() {
    this.controller = new window.AbortController()
    const { signal } = this.controller
    fetch('/one', { signal }).then(one => this.setState({ one }))
    fetch('/two', { signal }).then(two => this.setState({ two }))
  }
  componentWillUnmount() {
    this.controller.signal.abort()
  }
}