Context is read by components regardless of contextTypes definition

[wojtekmaj]

Consider the following, simplified example:

class NotGonnaRead extends Component {
  render() {
    return (
      <p>My favorite color is {this.context.favoriteColor}</p>
    );
  }
}

class WillRead extends Component {
  render() {
    return (
      <p>My favorite color is {this.context.favoriteColor}</p>
    );
  }
}

WillRead.contextTypes = {
  favoriteColor: PropTypes.string,
}

class FavoriteColorProvider extends Component {
  getChildContext() {
    return {
      favoriteColor: 'purple',
    };
  }
}

If we render it like so:

<FavoriteColorProvider>
    <NotGonnaRead />
</FavoriteColorProvider>

then the output is going to be My favorite color is .

Rendering this, however:

If we render it like so:

<FavoriteColorProvider>
    <WillRead />
</FavoriteColorProvider>

will correctly output My favorite color is purple.

Current behavior

If we would like to test if NotGonnaRead component is behaving properly (which it isn't), we would need to do something along the lines:

shallow(
  <NotGonnaRead />,
  { context: { favoriteColor: 'purple' } }
);

This will render <p>My favorite color is purple</p>.

Expected behavior

This example should render <p>My favorite color is </p> as contextTypes are not correctly defined.

Your environment

API

• shallow
• mount
• render

Version

library	version
Enzyme	3.3.0
React	16.2.0

Adapter

• enzyme-adapter-react-16 1.1.1
• enzyme-adapter-react-15
• enzyme-adapter-react-15.4
• enzyme-adapter-react-14
• enzyme-adapter-react-13
• enzyme-adapter-react-helper
• others ( )

[ljharb]

This is probably related to #664 - but may also be distinct.

It's possible that enzyme isn't filtering context by contextTypes, but I'd also expect React to do that for us. Can you check in react 15, and see if the same thing occurs? (also in mount on both 15 and 16)

[minznerjosh]

This was fixed in facebook/react#11922. It was released in react-test-renderer v16.3. So I'm going to open a PR shortly that will fix it on enzyme's side for react@<16.3.