A little sandbox for testing code mods for upgrades
This README contains some quick notes and references for a meetup talk I prepared for React Denver.
This project was bootstrapped with Create React App.
Canvas Kit from Workday was added for some components to work with.
Let's bump Canvas Kit to the latest version, and see what happens.
npm install -S @workday/canvas-kit-react@8 @workday/canvas-kit-preview-react@8 @workday/canvas-kit-labs-react@8
Do things still run?
Check the upgrade guide:
Install the codemod as a dev dependency:
npm install -D @workday/canvas-kit-codemod
Run the code mod (yarn is easiest):
yarn canvas-kit-codemod v8 src
Checkout what changed.
Tree-shaking with slash imports
Time to explore with astexplorer.net!
export const meta = {
type: 'problem',
hasSuggestions: true,
fixable: false,
};
export function create(context) {
return {
ImportDeclaration(node) {
if(node.source.value === '@workday/canvas-kit-react')
context.report({
node: node.source,
message: 'Use a slash import for better tree shaking',
});
}
};
};
Add a way to run ESLint directly by adding this to the scripts in package.json:
"lint": "eslint src"
Make sure it works:
npm run lint
Following the developer guide, create a blank rule in local-eslint-rules/index.js:
module.exports = {
rules: {
"use-slash-imports": {
create: function (context) {
// rule implementation ...
},
},
},
};
Register it in devDependencies:
"eslint-plugin-local-rules": "file:./local-eslint-rules"
Add the rule to the config:
"eslintConfig": {
"extends": [
"react-app",
"react-app/jest"
],
"plugins": [
"local-rules"
],
"rules": {
"local-rules/use-slash-imports": 1
}
},
Does it work?
npm run lint
Oh, we need this!
npm install
Run it again!
npm run lint
OK, now what? Let's explore.
Upgrade React to 18.
Reference: https://reactjs.org/blog/2022/03/08/react-18-upgrade-guide.html#installing
That's insufficient! Try this instead:
npm install -S react@18 react-dom@18
In the project directory, you can run:
Runs the app in the development mode.
Open http://localhost:3000 to view it in your browser.
The page will reload when you make changes.
You may also see any lint errors in the console.
Launches the test runner in the interactive watch mode.
See the section about running tests for more information.
Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.
The build is minified and the filenames include the hashes.
Your app is ready to be deployed!
See the section about deployment for more information.
Note: this is a one-way operation. Once you eject, you can't go back!
If you aren't satisfied with the build tool and configuration choices, you can eject at any time. This command will remove the single build dependency from your project.
Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except eject will still work, but they will point to the copied scripts so you can tweak them. At this point you're on your own.
You don't have to ever use eject. The curated feature set is suitable for small and middle deployments, and you shouldn't feel obligated to use this feature. However we understand that this tool wouldn't be useful if you couldn't customize it when you are ready for it.
You can learn more in the Create React App documentation.
To learn React, check out the React documentation.
This section has moved here: https://facebook.github.io/create-react-app/docs/code-splitting
This section has moved here: https://facebook.github.io/create-react-app/docs/analyzing-the-bundle-size
This section has moved here: https://facebook.github.io/create-react-app/docs/making-a-progressive-web-app
This section has moved here: https://facebook.github.io/create-react-app/docs/advanced-configuration
This section has moved here: https://facebook.github.io/create-react-app/docs/deployment
This section has moved here: https://facebook.github.io/create-react-app/docs/troubleshooting#npm-run-build-fails-to-minify