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Jest snapshots change from v6 to v7

See original GitHub issue

Do you want to request a feature or report a bug?


What is the current behavior?

When generating shallow snapshots of react components with react-redux@6, if there is a connected component then its name looks like Connect(ComponentName). However, with react-redux@7, all connected component names look like Memo(ConnectFunction).

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem. Your bug will get fixed much faster if we can run your code and it doesn’t have dependencies other than React. Paste the link to a CodeSandbox ( or RN Snack ( example below:

If you run the tests in this sandbox you’ll see that the ConnectedButton component shows up as UNDEFINED in the snapshot. This is not the same behavior I have locally but it is also not what I would expect. I cannot determine the reason for the different behavior, maybe some dependencies from react-scripts are not up to date?

What is the expected behavior?

I would expect the component name to be something like: Memo(Connect(ComponentName)).

Which versions of React, ReactDOM/React Native, Redux, and React Redux are you using? Which browser and OS are affected by this issue? Did this work in previous versions of React Redux?

react@16.8.6 react-dom@16.8.6 react-redux@7.0.2 redux@4.0.1

Issue Analytics

  • State:closed
  • Created 4 years ago
  • Comments:14 (2 by maintainers)

github_iconTop GitHub Comments

HendrikThePendriccommented, May 13, 2019

As an alternative to the excellent suggestion by @ismay, you could also mock the connect function, like so:

jest.mock('react-redux', () => ({
    connect: jest.fn(() => component => `Connected${}`),

Only caveat is that the component does need to have a name.

c0d3scommented, Nov 26, 2019

from the looks of it, this should be fixed in jest v25

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