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**Do you want to request a *feature* or report a *bug*?** Bug, I guess

**What is the current behavior?** 


```
  console.error node_modules/fbjs/lib/warning.js:33
    Warning: Detected multiple renderers concurrently rendering the same context provider. This is currently unsupported.
```

Steps to reproduce the behavior:
1. `git clone https://github.com/stereobooster/react-context-issue`
2. `cd react-context-issue`
3. `yarn`
4. `yarn test`

**What is the expected behavior?** no warning

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?** React 16.4. Browser not affected, because error is in node.js

Open this because of https://github.com/facebook/react/pull/13127#issuecomment-402527012

Issue happens because of Enzyme (https://github.com/airbnb/enzyme/issues/1693), code is unreleased, so I copy-pasted it from master. 

I'm looking for advice or some clue on how to fix this, so I would be able to create PR in Enzyme repo (or in React repo if this is the case). Thank you.


'\n    in Rectangle (at **)',
    ]);
  });
  it('should generate a <Shape> with props for drawing the Wedge', () => {
    const wedge = ReactTestRenderer.create(
      <Wedge outerRadius={50} startAngle={0} endAngle={360} fill="blue" />,
    );
    expect(wedge.toJSON()).toMatchSnapshot();
  });
  it('should return null if startAngle equals to endAngle on Wedge', () => {
    const wedge = ReactTestRenderer.create(
      <Wedge outerRadius={50} startAngle={0} endAngle={0} fill="blue" />,
    );
    expect(wedge.toJSON()).toBeNull();
  });
  it('should warn if outerRadius/startAngle/endAngle is missing on a Wedge component', () => {
    expect(() => ReactTestRenderer.create(<Wedge fill="blue" />)).toWarnDev([
      'Warning: Failed prop type: The prop `outerRadius` is marked as required in `Wedge`, ' +
        'but its value is `undefined`.' +
        '\n    in Wedge (at **)',
      'Warning: Failed prop type: The prop `startAngle` is marked as required in `Wedge`, ' +
        'but its value is `undefined`.' +
        '\n    in Wedge (at **)',
      'Warning: Failed prop type: The prop `endAngle` is marked as required in `Wedge`, ' +
        'but its value is `undefined`.' +
        '\n    in Wedge (at **)',
    ]);
  });
});