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## Summary This PR: - Adds the `"sideEffects": false` flag to the `react-is` package, to enable proper tree-shaking ## How did you test this change? React-Redux v9 beta switches its artifacts from separate JS files to pre-bundled artifacts. While testing builds locally, I noticed that our use of `react-is` was no longer getting tree-shaken from Vite builds, despite `react-is` only being used by our `connect` API and `connect` itself getting shaken out of the final bundle. Hand-adding `"sideEffects": false` to the `react-is` package locally convinced Vite (+Rollup) to properly tree-shake `react-is` out of the bundle when it wasn't being used. I'd love to see this published as v18.2.1 as soon as this PR is merged - we're hoping to release React-Redux v9 in the next few weeks!
react-is
This package allows you to test arbitrary values and see if they're a particular React element type.
Installation
# Yarn
yarn add react-is
# NPM
npm install react-is
Usage
Determining if a Component is Valid
import React from "react";
import * as ReactIs from "react-is";
class ClassComponent extends React.Component {
render() {
return React.createElement("div");
}
}
const FunctionComponent = () => React.createElement("div");
const ForwardRefComponent = React.forwardRef((props, ref) =>
React.createElement(Component, { forwardedRef: ref, ...props })
);
const Context = React.createContext(false);
ReactIs.isValidElementType("div"); // true
ReactIs.isValidElementType(ClassComponent); // true
ReactIs.isValidElementType(FunctionComponent); // true
ReactIs.isValidElementType(ForwardRefComponent); // true
ReactIs.isValidElementType(Context.Provider); // true
ReactIs.isValidElementType(Context.Consumer); // true
ReactIs.isValidElementType(React.createFactory("div")); // true
Determining an Element's Type
Context
import React from "react";
import * as ReactIs from 'react-is';
const ThemeContext = React.createContext("blue");
ReactIs.isContextConsumer(<ThemeContext.Consumer />); // true
ReactIs.isContextProvider(<ThemeContext.Provider />); // true
ReactIs.typeOf(<ThemeContext.Provider />) === ReactIs.ContextProvider; // true
ReactIs.typeOf(<ThemeContext.Consumer />) === ReactIs.ContextConsumer; // true
Element
import React from "react";
import * as ReactIs from 'react-is';
ReactIs.isElement(<div />); // true
ReactIs.typeOf(<div />) === ReactIs.Element; // true
Fragment
import React from "react";
import * as ReactIs from 'react-is';
ReactIs.isFragment(<></>); // true
ReactIs.typeOf(<></>) === ReactIs.Fragment; // true
Portal
import React from "react";
import ReactDOM from "react-dom";
import * as ReactIs from 'react-is';
const div = document.createElement("div");
const portal = ReactDOM.createPortal(<div />, div);
ReactIs.isPortal(portal); // true
ReactIs.typeOf(portal) === ReactIs.Portal; // true
StrictMode
import React from "react";
import * as ReactIs from 'react-is';
ReactIs.isStrictMode(<React.StrictMode />); // true
ReactIs.typeOf(<React.StrictMode />) === ReactIs.StrictMode; // true