将 mini-css-extract-plugin 与 postcss-loader 结合使用时，模块构建失败 预期行为实际行为代码

问题描述

• webpack 5.37.1
• mini-css-extract-plugin 1.6.0
• postcss-loader 5.3.0
• 小于 4.1.1

预期行为

构建成功。

实际行为

将 mini-css-extract-plugin 与 postcss-loader 结合使用时，模块构建失败。如果我从加载程序列表中删除 postcss-loader，那么它会正确构建。 mini-css-extract-plugin 或 postcss-loader 有问题？

ERROR in ./src/views/app.vue?vue&type=style&index=0&lang=less& (./node_modules/mini-css-extract-plugin/dist/loader.js!./node_modules/css-loader/dist/cjs.js??clonedRuleSet-7[0].rules[0].use[1]!./node_modules/vue-loader/lib/loaders/stylePostLoader.js!./node_modules/postcss-loader/dist/cjs.js??clonedRuleSet-7[0].rules[0].use[2]!./node_modules/less-loader/dist/cjs.js??clonedRuleSet-7[0].rules[0].use[3]!./node_modules/vue-loader/lib/index.js??vue-loader-options!./src/views/app.vue?vue&type=style&index=0&lang=less&)
Module build Failed (from ./node_modules/mini-css-extract-plugin/dist/loader.js):
ModuleBuildError: Module build Failed (from ./node_modules/postcss-loader/dist/cjs.js):
TypeError: node.getIterator is not a function
    at LazyResult.visitTick (E:\demo\node_modules\postcss\lib\lazy-result.js:522:33)
    at LazyResult.runAsync (E:\demo\node_modules\postcss\lib\lazy-result.js:402:30)
    at async Object.loader (E:\demo\node_modules\postcss-loader\dist\index.js:87:14)
    at processResult (E:\demo\node_modules\webpack\lib\normalModule.js:700:19)
    at E:\demo\node_modules\webpack\lib\normalModule.js:806:5
    at E:\demo\node_modules\loader-runner\lib\LoaderRunner.js:399:11
    at E:\demo\node_modules\loader-runner\lib\LoaderRunner.js:251:18
    at context.callback (E:\demo\node_modules\loader-runner\lib\LoaderRunner.js:124:13)
    at Object.loader (E:\demo\node_modules\postcss-loader\dist\index.js:96:7)
 @ ./src/views/app.vue?vue&type=style&index=0&lang=less& 1:0-482 1:0-482
 @ ./src/views/app.vue 4:0-64
 @ ./src/main.js 7:0-32 28:13-20

代码

    exports.cssLoaders = function (options) {
        options = options || {};

        const cssLoader = {
            loader: 'css-loader',options: {
                sourceMap: options.sourceMap
            }
        }

        const postcssLoader = {
            loader: 'postcss-loader',options: {
                sourceMap: options.sourceMap
            }
        }

        function generateLoaders (loader,loaderOptions) {
            const loaders = [];

            if (options.extract) {
                loaders.push(MiniCssExtractPlugin.loader)
            } else {
                loaders.push('vue-style-loader')
            }

            loaders.push(cssLoader)

            if (options.usePostCSS) {
                loaders.push(postcssLoader)
            }

            if (loader) {
                loaders.push({
                    loader: loader + '-loader',options: Object.assign({},loaderOptions,{
                        sourceMap: options.sourceMap
                    })
                })
            }

            return loaders
        }
        return {
            css: generateLoaders(),postcss: generateLoaders(),less: generateLoaders('less')
        }
    }

解决方法

我找到了导致错误的 postcss 插件 postcss-px2rem-exclude。