hermes | A JavaScript engine optimized for running React Native

by facebook C++ Version: v0.12.0 License: MIT

X-Ray Key Features Code Snippets Community Discussions(10)Vulnerabilities Install Support

kandi X-RAY | hermes Summary

hermes is a C++ library typically used in Mobile, React Native applications. hermes has no bugs, it has a Permissive License and it has medium support. However hermes has 4 vulnerabilities. You can download it from GitHub.

Hermes is a JavaScript engine optimized for fast start-up of React Native apps. It features ahead-of-time static optimization and compact bytecode. If you're only interested in using pre-built Hermes in a new or existing React Native app, you do not need to follow this guide or have direct access to the Hermes source. Instead, just follow these instructions to enable Hermes. Noted that each Hermes release is aimed at a specific RN version. The rule of thumb is to always follow Hermes releases strictly. Version mismatch can result in instant crash of your apps in the worst case scenario. If you want to know how to build and hack on Hermes directly, and/or integrate Hermes built from source into a React Native app then read on.

Support

Quality

Security

License

Reuse

Support

hermes has a medium active ecosystem.

It has 7876 star(s) with 522 fork(s). There are 134 watchers for this library.

It had no major release in the last 12 months.

There are 96 open issues and 440 have been closed. On average issues are closed in 542 days. There are 34 open pull requests and 0 closed requests.

It has a neutral sentiment in the developer community.

The latest version of hermes is v0.12.0

Quality

hermes has 0 bugs and 0 code smells.

Security

hermes has 4 vulnerability issues reported (2 critical, 2 high, 0 medium, 0 low).

hermes code analysis shows 0 unresolved vulnerabilities.

There are 0 security hotspots that need review.

License

hermes is licensed under the MIT License. This license is Permissive.

Permissive licenses have the least restrictions, and you can use them in most projects.

Reuse

hermes releases are available to install and integrate.

Installation instructions are not available. Examples and code snippets are available.

Top functions reviewed by kandi - BETA

kandi's functional review helps you automatically verify the functionalities of the libraries and avoid rework.
Currently covering the most popular Java, JavaScript and Python libraries. See a Sample of hermes

Get all kandi verified functions for this library.

hermes Key Features

No Key Features are available at this moment for hermes.

hermes Examples and Code Snippets

No Code Snippets are available at this moment for hermes.

Community Discussions

Trending Discussions on hermes

Hook Error After Implementing Redux Toolkit into Authentication

RCT-Folly error when using hermes with iOS

Moment returning an invalid date while using Hermes JS Engine

Could not find com.google.android:flexbox:1.0.0 react-native-intercom

-[FBLPromise HTTPBody]: unrecognized selector sent to instance

RN Release build fails, but debug runs. Error:Execution failed for task ':app:compileReleaseJavaWithJavac'

React Native app crashing on Proguard Enable

The React Native app installed from apk stuck after initial page

Measuring the Performance with the Hermes Engine

React Native: RCT-Folly fatal error - 'fmt/compile.h' file not found

QUESTION

Hook Error After Implementing Redux Toolkit into Authentication

Asked 2022-Apr-16 at 07:31

I keep getting an error when I run my app, and the screen is just white.

...

ANSWER

Answered 2022-Apr-16 at 07:31

In Profile Screen, you are calling const dispatch = useDispatch(); which is outside of the component and is an invalid call. It has to be called in inside ProfileScreen. When you are not sure where the problem occurs try commenting you code and see if it works without them. Like commenting your screens one by one would help you find which screen the error is caused in etc.

Source https://stackoverflow.com/questions/71891737

QUESTION

RCT-Folly error when using hermes with iOS

Asked 2022-Mar-20 at 03:32

When enabling hermes in the Podfile and rebuilding the build it fails due to RCT-Folly. No idea what it does.

To re-initialise everything I use the following:

rm -rf node_modules && rm package-lock.json && npm install && cd ios && rm -rf Pods && rm Podfile.lock && pod deintegrate && pod setup && pod install && cd ..

I also start the metro bundler with:

npx react-native --reset-cache

Anyone has a solution?

The app uses react-native v0.64 and we want to have a better performance using hermes.

All information:

ios/Podfile

...

ANSWER

Answered 2021-Jul-23 at 16:11

After lots of trial and error I found a working solution. It's a bit strange, but I had to enable Flipper. I did not find a way without it.

Thanks to this answer: https://github.com/facebook/react-native/issues/31179#issuecomment-831932941 I found out about fixing Pods.

This is my Podfile now:

Source https://stackoverflow.com/questions/68497865

QUESTION

Moment returning an invalid date while using Hermes JS Engine

Asked 2022-Mar-10 at 09:15

When I was using jsc Engine, everything was working fine but when I shifted from jsc engine to Hermes Engine in my react native app I started getting Invalid date where I was using moment.

CODE:

...

ANSWER

Answered 2022-Mar-10 at 09:15

After some R&D, I was able to figure out the issue myself so I thought to share it here.

Solution 1 :

Instead of using format like format("YYYY/MM/DD");. Use it like format("YYYY-MM-DD"); as this is one of the standard format that moment understands.

Solution 2:

If you need that format only(which was my case). You need to tell the moment the format that you are using. Like this:

Source https://stackoverflow.com/questions/71421582

QUESTION

Could not find com.google.android:flexbox:1.0.0 react-native-intercom

Asked 2022-Feb-25 at 18:17

I have a react-native project. After the bitnary (jcenter) shutted down I started to replace it. Currently I'm using mavenCentral(). Also I'm using the react-native-intercom (wrapper for intercom). When I'm trying to build gradlew assembleRelease. Its throws me an error.

...

ANSWER

Answered 2022-Jan-23 at 12:38

I solved it. If you are using the react-native-intercom wrapper. You need to update it, after update everything works fine

Source https://stackoverflow.com/questions/70801203

QUESTION

-[FBLPromise HTTPBody]: unrecognized selector sent to instance

Asked 2022-Feb-23 at 18:54

Using Firebase Analytics in an ios app, on a phone and simulator using ios 15.4, XCode 13.2.1 (13C100) in a React Native app. The app itself works, but when I try to add unit tests, the test runner fails with the unrecognized selector problem. I have combed the issues on SO, they either ask for more info and die on the vine, or reference the same four issues on Firebase's github.

The Podfile (below) doesn't have use_frameworks! so it's unlikely that duplicate symbols are the culprit. I tried the one concrete piece of advice from the github issues, pod deintegrate and recreate Podfile.lock, to no avail.

Here is the crash log, and below is the Podfile:

...

ANSWER

Answered 2022-Feb-02 at 21:53

Firebase/MLVision has been deprecated for a few years, so there may be some incompatible versions mixed into the app.

Best bet is to update to GoogleMLKit. If not that, you may be able to find compatible old versions by exploring the information in the generated Podfile.lock.

Source https://stackoverflow.com/questions/70959972

QUESTION

RN Release build fails, but debug runs. Error:Execution failed for task ':app:compileReleaseJavaWithJavac'

Asked 2022-Feb-07 at 03:56

I have a react-native app that runs perfectly well in debug, but fails on a release build. Running node 16.3.2 inside Windows 11 with react-native 0.63.4

Any thoughts on what to try would be greatly appreciated.

The build error from gradlew assembleRelease is:

...

ANSWER

Answered 2022-Feb-07 at 03:56

Try declaring the package separately above the imports like this:

Source https://stackoverflow.com/questions/71013290

QUESTION

React Native app crashing on Proguard Enable

Asked 2021-Dec-25 at 18:19

I have a React-Native app which is working perfectly fine on debug. But the app doesn't open on release build.

Disabling proguard fixes the issue. So I started looking installation documentation for each third party package installed and my proguard rules seemed fine. Sadly I couldn't detect which package is creating the issue.

My question is : how can I detect which third party package is causing this issue ?

Dependencies :

...

ANSWER

Answered 2021-Dec-25 at 18:19

You can test the release build and find errors in the console.

https://reactnative.dev/docs/signed-apk-android#testing-the-release-build-of-your-app

Source https://stackoverflow.com/questions/70480533

QUESTION

The React Native app installed from apk stuck after initial page

Asked 2021-Dec-23 at 09:49

I have generated a .apk file out of React Native 0.66.3 app (RN app) for test distribution by 3rd party distribution channel which only accept .apk format. After downloading to an android phone (API 30), the app is stuck with the registration page after entering user info and didn't go any further (after user enters reg info, the RN app shall route to verification page and send the user info to backend Nodejs server). The RN app is working fine on both emulator (API 27) and running on the same Android phone (API 30, connected with USB cable). The Android Studio used is 2021.3.1. The develop platform is macOS Big Sur.

I have no clue what is the problem. Here is the steps generating app distributed:

Generate app-release.aab file. Under /android do:
...

ANSWER

Answered 2021-Dec-17 at 10:56

This issue occur because you API not working. Solution: First: Check your API Links It must be start with https not with http. Second: Go to the Android Manifest file and add android:usesCleartextTraffic="true" inside the application starting tag. then sync your gradle and check it.

Source https://stackoverflow.com/questions/70295039

QUESTION

Measuring the Performance with the Hermes Engine

Asked 2021-Dec-15 at 12:35

I am trying to profiling in React Native and using hermes engine. I want measure the time in between a function call. In Js We can use console.time or performace.now but when I am using those fucntion with hermes engine I am getting "Undefined is not a function" Error.

When I am running the same code with Chrome debugger it is working fine.

Can anyone suggest how i can implement the below code with the hermes engine.

...

ANSWER

Answered 2021-Dec-15 at 12:35

Update:

I am able to solve the problem by using the below code

Source https://stackoverflow.com/questions/69739828

QUESTION

React Native: RCT-Folly fatal error - 'fmt/compile.h' file not found

Asked 2021-Nov-25 at 13:01

I want to enable Hermes for my iOS react native project but I have next error:

...

ANSWER

Answered 2021-Nov-25 at 12:48

Just set header search paths to fmt sources directly for RCT-Folly target in post_install to resolve this issue:

Podfile:

Source https://stackoverflow.com/questions/70111403

Community Discussions, Code Snippets contain sources that include Stack Exchange Network

Vulnerabilities

No vulnerabilities reported

Install hermes

You can download it from GitHub.

Support

The main purpose of this repository is to continue to evolve Hermes, making it faster and more efficient. We are grateful to the community for contributing bugfixes and improvements. Read below to learn how you can take part in improving Hermes.

Find more information at: