Fast Refresh does not work on RNW 0.62

[AlexandroSosa]

Hello there :)

I have been playing around with rn-windows/macos and it seems that enabling FR always leads to a full reload of the UI even when editing isolated functional components. In contrast, in react-native android/ios only the component subtree which has been affected by the change ends up being re-rendered.
Is this behavior by design or is there an existing limitation imposed by the current implementation of fast refresh? If it is the latter I would be more than happy to work on a pull request.

Thanks for reading!

This issue lacks the environment info requested in the bug template. Please edit your issue report to add this information.

If you are using latest version:

1. react-native -v:
2. react-native run-windows --info:

Otherwise if --info doesn't exist:

1. react-native -v:
2. npm ls rnpm-plugin-windows:
3. npm ls react-native-windows:
4. node -v:
5. npm -v:
6. yarn --version:

[chrisglein]

Fast Refresh should be working for Windows at least as of 61.5. Can you clarify what version you're using? Fast Refresh came with 61, and there's very recently a version of macOS that supports 61.

[AlexandroSosa]

Hello Chris,

Spot on! It was a versioning issue. It seems the problem only occurs with the 0.62 preview.

Working setup:
System:
OS: Windows 10 10.0.18362
CPU: (6) x64 Intel(R) Xeon(R) CPU E5-2680 v2 @ 2.80GHz
Memory: 2.50 GB / 8.00 GB
Binaries:
Node: 12.16.3 - C:\Program Files\nodejs\node.EXE
Yarn: 1.22.4 - ~\AppData\Roaming\npm\yarn.CMD
npm: 6.14.4 - C:\Program Files\nodejs\npm.CMD
npmPackages:
react: 16.9.0 => 16.9.0
react-native: 0.61.5 => 0.61.5
react-native-windows: ^0.61.0-0 => 0.61.7
Installed UWP SDKs:
10.0.17134.0
10.0.17763.0
10.0.18362.0

Broken Fast Refresh:

System:
OS: Windows 10 10.0.18362
CPU: (6) x64 Intel(R) Xeon(R) CPU E5-2680 v2 @ 2.80GHz
Memory: 2.41 GB / 8.00 GB
Binaries:
Node: 12.16.3 - C:\Program Files\nodejs\node.EXE
Yarn: 1.22.4 - ~\AppData\Roaming\npm\yarn.CMD
npm: 6.14.4 - C:\Program Files\nodejs\npm.CMD
npmPackages:
react: 16.11.0 => 16.11.0
react-native: ^0.62.0-0 => 0.62.2
react-native-windows: ^0.62.0-0 => 0.62.0-preview.2
Installed UWP SDKs:
10.0.17134.0
10.0.17763.0
10.0.18362.0

[NickGerleman]

We're not yet tracking fast refresh issues with 0.62. Andrew Coates (@acoates-ms) could you take a look?