The suggested .cjs resolver fix on 3.5.4 adds 10 seconds of boot on iOS.

[p-gag]

Intended outcome:
Update Apollo client 3.3.11 -> 3.5.8 on a react-native app.

Actual outcome:
After doing it (including the .cjs resolver fix) our react-native app boot went from 1 second to 10. For the record, it felt like the whole JS code was slow but around 8 seconds was into AWS Cognito Auth.signIn. The problem occurred only on the iOS device and was not present on the simulator.

I've track down the problem to the .cjs resolver change proposed here. When I rollback everything (clean-rebuild) with this, I get the ugly 10 seconds boot.

How to reproduce the issue:
I understand I don't have a clean isolated repro but this thing was hard to find, mostly because it's device specific. There are lot of slow boot problems around react-native so my hope is to help someone else and maybe it will lead to more info on the problem.

Versions

• with .cjs resolver fix -> slow boot

• without -> just fine

  System:
  OS: macOS 11.3.1
  Binaries:
  Node: 16.14.0 - /usr/local/bin/node
  Yarn: 1.22.10 - /usr/local/bin/yarn
  npm: 8.3.1 - /usr/local/bin/npm
  Browsers:
  Chrome: 98.0.4758.102
  Safari: 14.1
  npmPackages:
  @apollo/client: ^3.3.11 => 3.3.11

[benjamn]

@p-gag Could you try running npm i @apollo/client@beta to get version 3.7.0-alpha.4? I believe PR #9716 should allow you to remove the previously recommended sourceExts code from metro.config.js (and possibly remove that file completely, if there's nothing else in it), which I'm guessing will solve the slow boot time, or at least uncover some other reason for the delay.

[benjamn]

Just tested @apollo/client@3.6.4 in a React Native project without using a metro.config.js file, and it seemed to work, so I'm fairly confident this issue will be solved if you update (npm i @apollo/client@latest) and also delete the previous fix from metro.config.js. Please let us know if that doesn't fix it for you @p-gag!