Webpack 外部反应导致 React Hooks 错误

Question

我是FireJS 的作者。我遇到了一个带有反应钩子的issue。

(node:21793) UnhandledPromiseRejectionWarning: Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:
1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app
See https://reactjs.org/warnings/invalid-hook-call-warning.html for tips about how to debug and fix this problem.
    at resolveDispatcher (webpack://%5Bname%5D/./node_modules/react/cjs/react.development.js?:1465:13)
    at useState (webpack://%5Bname%5D/./node_modules/react/cjs/react.development.js?:1496:20)
    at Header (webpack://__FIREJS_APP__/./src/pages/404.js?:22:73)
    at processChild (/media/dedsec/Data/Projects/FireJS/node_modules/react-dom/cjs/react-dom-server.node.development.js:3043:14)
    at resolve (/media/dedsec/Data/Projects/FireJS/node_modules/react-dom/cjs/react-dom-server.node.development.js:2960:5)
    at ReactDOMServerRenderer.render (/media/dedsec/Data/Projects/FireJS/node_modules/react-dom/cjs/react-dom-server.node.development.js:3435:22)
    at ReactDOMServerRenderer.read (/media/dedsec/Data/Projects/FireJS/node_modules/react-dom/cjs/react-dom-server.node.development.js:3373:29)
    at Object.renderToString (/media/dedsec/Data/Projects/FireJS/node_modules/react-dom/cjs/react-dom-server.node.development.js:3988:27)
    at /media/dedsec/Data/Projects/FireJS/dist/architects/StaticArchitect.js:51:36
    at default_1.render (/media/dedsec/Data/Projects/FireJS/dist/architects/StaticArchitect.js:57:11)
    at /media/dedsec/Data/Projects/FireJS/dist/FireJS.js:99:143
    at default_1.<anonymous> (/media/dedsec/Data/Projects/FireJS/dist/classes/Plugin.js:20:13)
    at Generator.next (<anonymous>)
    at /media/dedsec/Data/Projects/FireJS/dist/classes/Plugin.js:8:71
    at new Promise (<anonymous>)
    at __awaiter (/media/dedsec/Data/Projects/FireJS/dist/classes/Plugin.js:4:12)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:21793) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2)
(node:21793) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

我已经仔细检查了help page 中给出的每一个建议，但我无法解决问题。

我将 react 捆绑为外部块，然后将其用作库。这是我的webpack config 的快照；

            target: 'web',
            mode: this.$.config.pro ? "production" : "development",
            entry: {
                "React": "react",
                "ReactDOM": "react-dom",
                "ReactHelmet": "react-helmet",
            },
            output: {
                path: this.$.config.paths.lib,
                filename: "e[contentHash].js",
                library: "[name]",//make file as library so it can be imported for static generation
                libraryTarget: "window"
            }

        mergedConfig.externals["react"] = 'React';
        mergedConfig.externals["react-dom"] = "ReactDOM";
        mergedConfig.externals["react-helmet"] = "ReactHelmet";
        const cssLoaderUse = [MiniCssExtractPlugin.loader,
            {
                loader: 'css-loader',
                options: {
                    modules: {
                        hashPrefix: 'hash',
                    },
                },
            }
        ];
        mergedConfig.module.rules.push({
                test: /\.(js|jsx)$/,
                use: {
                    loader: 'babel-loader',
                    options: {
                        presets: ["@babel/preset-env", "@babel/preset-react"]
                    }
                },
            }, {
                test: /\.sass$/i,
                loader: [...cssLoaderUse, 'sass-loader']
            }, {
                test: /\.less$/i,
                loader: [...cssLoaderUse, 'less-loader']
            }, {
                test: /\.css$/i,
                use: cssLoaderUse
            }
        );

我将其导出为window.__FIREJS_APP__

        mergedConfig.output.library = "__FIREJS_APP__";
        mergedConfig.output.libraryTarget = "window";

我正在尝试运行的反应文件

import React, { useState } from 'react';

export default() => {
  // Declare a new state variable, which we'll call "count"
  const [count, setCount] = useState(0);

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

渲染过程

runApp: function (func = ReactDOM.render) {
        func(React.createElement(window.__FIREJS_APP__.default, {content: window.__MAP__.content}),
            document.getElementById("root")
        );
    }

if (window.__SSR__)
    LinkApi.runApp(ReactDOM.hydrate)
else
    LinkApi.runApp()

为什么我认为这是一个 webpack 问题？

以前，当我正常捆绑文件时，React Hooks 工作完美，但当我切换到外部反应时。 React Hooks 开始导致这个问题。

Answer 1

我想出了如何解决这个问题。您需要将react、react-dom 和react-dom/server 捆绑到同一个捆绑包中。

例如：

window.React = require("react");
window.ReactDOM = require("react-dom")
window.ReactDOMServer = require("react-dom/server")

捆绑上述文件并将其作为您的第一个脚本导入。