Decision Table
Good Faith Declaration
Description
When using jest.useFakeTimers() in tests, RNRH logs a whole lot of warnings, even when only rendering the component once.
I've also found the root cause. When using the fake timers, Jest patches performance.now() (among others). Crucially, it sets the return value to 0 by default (you can advance this value using jest.advanceTimersByTime() and related utilities, but the default is 0)
Unfortunately, RNRH also uses 0 as the default of the lastUpdate ref (source). Therefore, on the very first render, RNRH thinks the previous render happened exactly 0ms ago, and prints a bunch of warnings!
I realize this is not really a "bug" per se, and definitely won't affect any end users. However, it might confuse other devs like it confused me, and the fix is probably quite simple.
React Native Information
System:
OS: macOS 14.2.1
CPU: (10) arm64 Apple M1 Pro
Memory: 1.43 GB / 32.00 GB
Shell:
version: "5.9"
path: /bin/zsh
Binaries:
Node:
version: 20.13.1
path: /private/var/folders/fk/c9z1tyhj02nfdn9dz_71vjk80000gq/T/xfs-3bfe75a4/node
Yarn:
version: 3.2.3
path: /private/var/folders/fk/c9z1tyhj02nfdn9dz_71vjk80000gq/T/xfs-3bfe75a4/yarn
npm:
version: 10.5.2
path: ~/.local/state/fnm_multishells/1402_1720596864919/bin/npm
Watchman:
version: 2024.05.06.00
path: /opt/homebrew/bin/watchman
Managers:
CocoaPods:
version: 1.15.0
path: /Users/tuur/.rbenv/shims/pod
SDKs:
iOS SDK:
Platforms:
- DriverKit 23.5
- iOS 17.5
- macOS 14.5
- tvOS 17.5
- visionOS 1.2
- watchOS 10.5
Android SDK: Not Found
IDEs:
Android Studio: 2022.2 AI-222.4459.24.2221.9862592
Xcode:
version: 15.4/15F31d
path: /usr/bin/xcodebuild
Languages:
Java:
version: 17.0.9
path: /Users/tuur/.jenv/shims/javac
Ruby:
version: 3.0.6
path: /Users/tuur/.rbenv/shims/ruby
npmPackages:
"@react-native-community/cli": Not Found
react:
installed: 18.2.0
wanted: 18.2.0
react-native:
installed: 0.72.14
wanted: 0.72.14
react-native-macos: Not Found
npmGlobalPackages:
"*react-native*": Not Found
Android:
hermesEnabled: true
newArchEnabled: false
iOS:
hermesEnabled: true
newArchEnabled: false
RNRH Version
6.3.4
Tested Platforms
Reproduction Platforms
Minimal, Reproducible Example
#664
Additional Notes
No response
Decision Table
<yyy>is not rendered”Good Faith Declaration
Description
When using
jest.useFakeTimers()in tests, RNRH logs a whole lot of warnings, even when only rendering the component once.I've also found the root cause. When using the fake timers, Jest patches
performance.now()(among others). Crucially, it sets the return value to0by default (you can advance this value usingjest.advanceTimersByTime()and related utilities, but the default is0)Unfortunately, RNRH also uses
0as the default of thelastUpdateref (source). Therefore, on the very first render, RNRH thinks the previous render happened exactly 0ms ago, and prints a bunch of warnings!I realize this is not really a "bug" per se, and definitely won't affect any end users. However, it might confuse other devs like it confused me, and the fix is probably quite simple.
React Native Information
System: OS: macOS 14.2.1 CPU: (10) arm64 Apple M1 Pro Memory: 1.43 GB / 32.00 GB Shell: version: "5.9" path: /bin/zsh Binaries: Node: version: 20.13.1 path: /private/var/folders/fk/c9z1tyhj02nfdn9dz_71vjk80000gq/T/xfs-3bfe75a4/node Yarn: version: 3.2.3 path: /private/var/folders/fk/c9z1tyhj02nfdn9dz_71vjk80000gq/T/xfs-3bfe75a4/yarn npm: version: 10.5.2 path: ~/.local/state/fnm_multishells/1402_1720596864919/bin/npm Watchman: version: 2024.05.06.00 path: /opt/homebrew/bin/watchman Managers: CocoaPods: version: 1.15.0 path: /Users/tuur/.rbenv/shims/pod SDKs: iOS SDK: Platforms: - DriverKit 23.5 - iOS 17.5 - macOS 14.5 - tvOS 17.5 - visionOS 1.2 - watchOS 10.5 Android SDK: Not Found IDEs: Android Studio: 2022.2 AI-222.4459.24.2221.9862592 Xcode: version: 15.4/15F31d path: /usr/bin/xcodebuild Languages: Java: version: 17.0.9 path: /Users/tuur/.jenv/shims/javac Ruby: version: 3.0.6 path: /Users/tuur/.rbenv/shims/ruby npmPackages: "@react-native-community/cli": Not Found react: installed: 18.2.0 wanted: 18.2.0 react-native: installed: 0.72.14 wanted: 0.72.14 react-native-macos: Not Found npmGlobalPackages: "*react-native*": Not Found Android: hermesEnabled: true newArchEnabled: false iOS: hermesEnabled: true newArchEnabled: falseRNRH Version
6.3.4
Tested Platforms
Reproduction Platforms
Minimal, Reproducible Example
#664
Additional Notes
No response