React是否保持状态更新的顺序？

我知道React可以异步并批量执行状态更新以优化性能。因此，在调用之后，您将永远无法相信要更新的状态setState。但是你可以信任的反应更新相同的顺序状态setState被称为对

1. 相同的组件？
2. 不同的组件？

考虑在以下示例中单击按钮：

1.在以下情况下，是否有可能a为假而b为真：

class Container extends React.Component {
  constructor(props) {
    super(props);
    this.state = { a: false, b: false };
  }

  render() {
    return <Button onClick={this.handleClick}/>
  }

  handleClick = () => {
    this.setState({ a: true });
    this.setState({ b: true });
  }
}

2.在以下情况下，是否有可能a为假而b为真：

class SuperContainer extends React.Component {
  constructor(props) {
    super(props);
    this.state = { a: false };
  }

  render() {
    return <Container setParentState={this.setState.bind(this)}/>
  }
}

class Container extends React.Component {
  constructor(props) {
    super(props);
    this.state = { b: false };
  }

  render() {
    return <Button onClick={this.handleClick}/>
  }

  handleClick = () => {
    this.props.setParentState({ a: true });
    this.setState({ b: true });
  }
}

Keep in mind that these are extreme simplifications of my use case. I realize that I can do this differently, e.g. updating both state params at the same time in example 1, as well as performing the second state update in a callback to the first state update in example 2. However, this is not my question, and I am only interested in if there is a well defined way that React performs these state updates, nothing else.

Any answer backed up by documentation is greatly appreciated.