Fix node resolving in React 16 adapter

[gregberge]

I added a test relative to #1163 (comment)

I tried to fix it but I couldn't figure out when to use alternate node.

[gregberge]

@lelandrichardson It is probably not the cleaner way to do it but it fixes a huge bug. I think merging it and publishing a patch would be great!

[gaearon]

Do you have a plan for what we need to expose on React side to remove this hack?

[marvinpinto]

I was running into a an issue similar to #1153 so I followed @gaearon's advice and tried this patch out. It seemed to do the trick for me 👍

I had to sprinkle wrapper.update() after dom-manipulating events and it worked fine for the most part.

Here is what I did to test this locally:

• Cloned https://github.com/neoziro/enzyme.git
• Switched to the react-16-updated-props branch.
• Inside the cloned enzyme repo: lerna bootstrap && lerna run build
• Then replaced the enzyme, enzyme-adapter-react-16, and enzyme-adapter-utils packages (in my node_modules directory) with the newly built lerna alternatives (in the packages directory).

I ran into an oddity where enzyme was throwing the following error:

Enzyme Internal Error: configured enzyme adapter did not inherit from the EnzymeAdapter base class

I assumed it was something weird related to how I built this package and so I just commented out the relevant lines in validateAdapter.js - https://github.com/neoziro/enzyme/blob/react-16-updated-props/packages/enzyme/src/validateAdapter.js#L16-L21

[aweary]

Do you have a plan for what we need to expose on React side to remove this hack?

@gaearon ideally React would expose a way to call toTree on an instance. This logic is already duplicated from the test renderer, so unifying and exporting it could mean that future adapters don't need to implement toTree themselves.

[lelandrichardson]

@neoziro thanks for hitting this! I think this is good and am going to merge. It puts us in a strictly better state than where we are now.

That said, I'm definitely interested in hashing out more details with @aweary and @gaearon around getting the react 16 adapter to a state where it doesn't depend on any internals. I agree with Brandon that this likely doesn't need to be much more than just exposing a ReactTestUtils.toTree(instance) or something like this. The function itself is kind of already built for the test renderer, but isn't publicly exposed.

Perhaps this wednesday (at react wednesday) could be a good time to hash out some of these details.

In the mean time, I'm going to merge this to get some people unblocked.

Oh, also, @marvinpinto the error you got is indicative of multiple copies of enzyme being installed in your node_modules directory, thus instanceof doesn't match between them.

[gregberge]

@lelandrichardson you are welcome! It was a pleasure to help!