nyc
why-did-you-render
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nyc | why-did-you-render | |
---|---|---|
16 | 47 | |
5,521 | 10,783 | |
0.3% | 1.4% | |
4.7 | 7.0 | |
6 days ago | 23 days ago | |
JavaScript | JavaScript | |
ISC License | MIT License |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
nyc
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Migrating from Jest to Vitest for your React Application
Native code coverage via v8 or istanbul.
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Testing Vue components the right way
Writing tests is essential, and knowing whether you test all the required cases for your logic is even more critical. The most common testing coverage tool is Istanbul, where you can see how well your tests exercise your code by lines, functions, and branches. Below is an example of how the test coverage report looks in your terminal:
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Don't target 100% coverage
Here is a quote from istanbul, one of the most used code coverage tool:
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Unit testing like a Hacker
Unit testing framework was already implemented, using Vitest so I started hacking by setting up a coverage provider to explicitly identify the covered/uncovered lines and mentioned this to the maintainer in the comments. I used Istanbul 🇹🇷 for this purpose.
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Auto-Publish Your Test Coverage Report on GitHub Pages
Your project probably has a coverage report. If you’re using Jest as your unit test runner, generating a coverage report is embedded in it. It is done with Istanbul under the hood, which generates a nice HTML page presenting the entire project unit test coverage.
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Dear Linux, Privileged Ports Must Die
> This is a rant written by someone with just enough understanding to be dangerous, but not quite enough wisdom to know why things are still the way they are. Most of the complaints raised are subtly inaccurate.
Author seems aware of CAP_NET_BIND_SERVICE: https://source.small-tech.org/site.js/app/-/issues/169 and https://github.com/istanbuljs/nyc/issues/1281 – the "side effects" are NodeJS explicitly checking for it, so that's a NodeJS thing and not a Linux thing.
Yet curiously it's completely unmentioned in this article, in spite that this is probably what started the author's dislike of privileged ports. I guess it was inconvenient as it got in the way of angrily ranting.
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Comprehensive coverage Jest+Playwright in Next.js TS
This approach will create two json coverage files, which will be merged together by NYC. Therefore the results will be purely local. If You don't mind using online tools like Codecov or Coveralls for merging data from different tests, then go ahead and use them. They will probably also be more accurate. But if You still want to learn how to get coverage from E2E, then please read through
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When developing in React, what do you find most frustrating or cumbersome?
https://istanbul.js.org/ measures how much of your code is covered by tests
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Production Ready React
Jest uses a package called Istanbul to provide test coverage metrics such as statement, branch, function, and line coverage so that you can understand and enforce the quality of your test suite, providing more confidence in releases.
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Aggregating Unit Test Coverage for All Monorepo’s Packages
So let’s see if nyc (the code coverage generator) can help with that. Hmm… this documentation seems interesting! So basically what I understand from it is that I need to collect all the reports from the different packages and then run the nyc report over it. The flow should be like this:
why-did-you-render
- Too many rerenders in react?
- Lag issues with RN
- After a year developing with react, I think I've been doing all wrong
- How can I stop a component from reloading all the time?.
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How to speed up React Native screen when full of TextInput?
Check out why-did-you-render. It may tell you some more information.
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Why and How We Retired Elm at Culture Amp
It's a combination of many things, but imo one of the worst is all the footguns regarding state and the rerenders they cause
https://emnudge.dev/blog/react-hostage
It's so easy, that we monkey patch react to debug it https://github.com/welldone-software/why-did-you-render
Plus the vdom... Isn't great, the bundle size puts react at an inherit disadvantage, and the community has a knack for over reliance on bloated packages
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7 Proven Practices to Boost Development Speed and Project Quality
When we implemented the MVP of the fintech app, we had a quite complicated form. At that time, I was still young and inexperienced. And eventually, we realized that our project was slowing down. We had to spend additional hours figuring out the reason. We had many unnecessary re-renders because we ignored basic rules related to props in React. I wanted to do everything possible to avoid such situations in the future. So, I added to the project linters like this and an additional starting configuration to package.json to run why-did-you-render. In short, this plugin issues a warning if something is re-rendered unnecessarily and suggests how to avoid it. Also, we included running Lighthouse in headless mode. Some people say that premature optimizations are bad, but for me, it's a principle: do it right from the start.
- Free code review
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Is there a way to detect unwanted mutations in a React component?
maybe somethin like https://github.com/welldone-software/why-did-you-render
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React Dev Tools: much worse experience with functions/hooks
This might help you out a bit.
What are some alternatives?
jest - Delightful JavaScript Testing.
craco - Create React App Configuration Override, an easy and comprehensible configuration layer for Create React App.
istanbul - Yet another JS code coverage tool that computes statement, line, function and branch coverage with module loader hooks to transparently add coverage when running tests. Supports all JS coverage use cases including unit tests, server side functional tests and browser tests. Built for scale.
use-what-changed - A React hook and an easy to use babel-pugin to debug various React official hooks
Cucumber.js - Cucumber for JavaScript
nextjs-rewrite-test
playwright-test-coverage - Extends Playwright test to measure code coverage
react-render-tracker - React render tracker – a tool to discover performance issues related to unintentional re-renders and unmounts
mocha - ☕️ simple, flexible, fun javascript test framework for node.js & the browser
react-devtools - An extension that allows inspection of React component hierarchy in the Chrome and Firefox Developer Tools.
jasmine - Simple JavaScript testing framework for browsers and node.js
razzle - ✨ Create server-rendered universal JavaScript applications with no configuration