Janic Duplessis
7e2f17ffe2
Summary: When trying to implement e2e tests using maestro in a large app I ran into major performance issues. I tracked it down to the generation of recursive accessibility labels. The maestro iOS driver uses [XCUIElement snapshot dictionaryRepresentation](https://developer.apple.com/documentation/xctest/xcuielementsnapshot/dictionaryrepresentation) [here](https://github.com/mobile-dev-inc/Maestro/blob/96e8c9a2be3430be991c13d033486d52d2001334/maestro-ios-xctest-runner/maestro-driver-iosUITests/Routes/Handlers/ViewHierarchyHandler.swift#L234) to get a representation of the view hierarchy. The problem is that will query the accessibilityLabel for every single view, starting from the root of the app. It goes without saying that this is extremely slow since it traverses the view hierarchy, executing a recursive function on each one. I think the only way to fix this is to avoid generating these recursive labels when not needed. From my understanding these should only be needed for accessible views. ## Changelog: [IOS] [CHANGED] - Only generate recursive accessibility label for accessible elements Pull Request resolved: https://github.com/facebook/react-native/pull/51988 Test Plan: - Tested using VoiceOver in RN tester to make sure it works exactly the same. - Tested in an app using Maestro to make sure this fixes the performance issue. - Tested in RNTester running Maestro e2e test by creating a larger view hierarchy to make the problem more apparent, and simulate a real app. Using [this code](https://gist.github.com/janicduplessis/9f6b302d92b4e22ff5e8462a8a84e237) in RNTesterAppShared.js Before: ``` ❯ yarn e2e-test-ios yarn run v1.22.22 $ ./scripts/maestro-test-ios.sh Waiting for flows to complete... [Passed] flatlist (14s) [Passed] text (28s) [Passed] modal (16s) [Passed] image (8s) [Passed] button (10s) [Passed] legacy-native-module (32s) [Passed] pressable (32s) [Passed] new-arch-examples (35s) 8/8 Flows Passed in 2m 55s ✨ Done in 180.26s. ``` After: ``` ❯ yarn e2e-test-ios yarn run v1.22.22 $ ./scripts/maestro-test-ios.sh Waiting for flows to complete... [Passed] flatlist (7s) [Passed] text (15s) [Passed] modal (10s) [Passed] image (4s) [Passed] button (6s) [Passed] legacy-native-module (16s) [Passed] pressable (16s) [Passed] new-arch-examples (17s) 8/8 Flows Passed in 1m 31s ✨ Done in 97.53s. ``` Reviewed By: christophpurrer, joevilches Differential Revision: D76581949 Pulled By: cipolleschi fbshipit-source-id: 0689c7d43a0c865572c4ee5ea32ee9b2dcb33ad5
React Native
Learn once, write anywhere:
Build mobile apps with React.
Getting Started · Learn the Basics · Showcase · Contribute · Community · Support
React Native brings React's declarative UI framework to iOS and Android. With React Native, you use native UI controls and have full access to the native platform.
- Declarative. React makes it painless to create interactive UIs. Declarative views make your code more predictable and easier to debug.
- Component-Based. Build encapsulated components that manage their state, then compose them to make complex UIs.
- Developer Velocity. See local changes in seconds. Changes to JavaScript code can be live reloaded without rebuilding the native app.
- Portability. Reuse code across iOS, Android, and other platforms.
React Native is developed and supported by many companies and individual core contributors. Find out more in our ecosystem overview.
Contents
- Requirements
- Building your first React Native app
- Documentation
- Upgrading
- How to Contribute
- Code of Conduct
- License
📋 Requirements
React Native apps may target iOS 15.1 and Android 7.0 (API 24) or newer. You may use Windows, macOS, or Linux as your development operating system, though building and running iOS apps is limited to macOS. Tools like Expo can be used to work around this.
🎉 Building your first React Native app
Follow the Getting Started guide. The recommended way to install React Native depends on your project. Here you can find short guides for the most common scenarios:
📖 Documentation
The full documentation for React Native can be found on our website.
The React Native documentation discusses components, APIs, and topics that are specific to React Native. For further documentation on the React API that is shared between React Native and React DOM, refer to the React documentation.
The source for the React Native documentation and website is hosted on a separate repository, @facebook/react-native-website.
🚀 Upgrading
Upgrading to new versions of React Native may give you access to more APIs, views, developer tools, and other goodies. See the Upgrading Guide for instructions.
React Native releases are discussed in this discussion repo.
👏 How to Contribute
The main purpose of this repository is to continue evolving React Native core. We want to make contributing to this project as easy and transparent as possible, and we are grateful to the community for contributing bug fixes and improvements. Read below to learn how you can take part in improving React Native.
Code of Conduct
Facebook has adopted a Code of Conduct that we expect project participants to adhere to. Please read the full text so that you can understand what actions will and will not be tolerated.
Contributing Guide
Read our Contributing Guide to learn about our development process, how to propose bugfixes and improvements, and how to build and test your changes to React Native.
Open Source Roadmap
You can learn more about our vision for React Native in the Roadmap.
Good First Issues
We have a list of good first issues that contain bugs which have a relatively limited scope. This is a great place to get started, gain experience, and get familiar with our contribution process.
Discussions
Larger discussions and proposals are discussed in @react-native-community/discussions-and-proposals.
📄 License
React Native is MIT licensed, as found in the LICENSE file.