Neil DharandFacebook GitHub Bot
cd5a8c48c5
Summary: Constructing a `JSError` currently catches all exceptions that occur, regardless of their type, and embeds the information from them in the newly created `JSError`. This means that the type of exceptions can be silently changed. This results in a bug if Hermes is built with `HERMESVM_EXCEPTION_ON_OOM` enabled. The OOM exception will get converted to a `JSError`, which in turn can get converted into a regular JS exception. The regular JS exception can then be caught by JS and ignored. This leads to the VM continuing to execute in a bad state. I considered three ways to fix this: 1. Add a new type of exception to JSI that is intentionally meant to be ignored, and the Hermes OOM exception then subclasses it. 2. Propagate all exceptions that happen when constructing `JSError`. 3. Propagate all exceptions except `JSIException`s when constructing `JSError`. The first is technically the most surgical, but it adds complexity to JSI, and will require some extra machinery to implement since we wouldn't be able to throw it directly from inside the VM. I'm also not comfortable with the idea of JSI suppressing exceptions that are completely unrelated to JSI. The second is the simplest, and seems to match what JS would do if `throw new Error()` itself threw, but there is some possibility that it is a change in behaviour for existing code. So the third approach, which is implemented in this diff, tries to compromise between the two. Hermes can only ever throw `JSIException`s from regular JS operations, so there should be no change for existing code (except code that uses exceptions on OOM, which is what we're trying to fix). Any other exception gets passed through to the caller. Changelog: [Internal][Fixed] - Fixed handling of Hermes OOM exceptions in JSI. Reviewed By: jpporto Differential Revision: D41831616 fbshipit-source-id: 42e0dde1c4acc016ab19533941c58fc1797ba1c2
React Native
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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.
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React Native is developed and supported by many companies and individual core contributors. Find out more in our ecosystem overview.
Contents
- Requirements
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- Documentation
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- How to Contribute
- Code of Conduct
- License
📋 Requirements
React Native apps may target iOS 12.4 and Android 5.0 (API 21) 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.
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🚀 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
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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.
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