vue inspect --rules error

[JFGHT]

Version

3.0.0

Node and OS info

yarn 1.9.4 / Linux Mint 19

Steps to reproduce

Just typing vue inspect --rule vue OR vue inspect --rules shows this error.

What is expected?

A list of webpack rules.

What is actually happening?

TypeError: Cannot read property '0' of undefined
at config.module.rules.map.r (/home/jesus/apps/annexum-new-webpack/node_modules/@vue/cli-service/lib/commands/inspect.js:25:55)
at Array.map ()
at api.registerCommand.args (/home/jesus/apps/annexum-new-webpack/node_modules/@vue/cli-service/lib/commands/inspect.js:25:33)
at Service.run (/home/jesus/apps/annexum-new-webpack/node_modules/@vue/cli-service/lib/Service.js:203:12)
at Object. (/home/jesus/apps/annexum-new-webpack/node_modules/@vue/cli-service/bin/vue-cli-service.js:22:9)
at Module._compile (module.js:649:30)
at Object.Module._extensions..js (module.js:660:10)
at Module.load (module.js:561:32)
at tryModuleLoad (module.js:501:12)
at Function.Module._load (module.js:493:3)
at Function.Module.runMain (module.js:690:10)
at startup (bootstrap_node.js:194:16)
at bootstrap_node.js:666:3

[haoqunjiang]

Could you provide your vue.config.js please? I suppose it is caused by some custom rules in your config file.

[JFGHT]

Here you are:

const StyleLintPlugin = require('stylelint-webpack-plugin');

module.exports = {
  devServer: {
    https: true,
  },
  // Fixing CircleCi Bug related to thread-loader
  parallel: !process.env.CIRCLECI,
  configureWebpack: {
    plugins: [
      new StyleLintPlugin({ emitErrors: false, syntax: 'scss' }),
    ],
  },
  chainWebpack: (config) => {
    const svgRule = config.module.rule('svg');

    svgRule.uses.clear();

    svgRule
      .oneOf('inline')
      .resourceQuery(/inline/)
      .use('vue-svg-loader')
      .loader('vue-svg-loader')
      .end()
      .end()
      .oneOf('external')
      .use('file-loader')
      .loader('file-loader')
      .options({ name: 'assets/[name].[hash:8].[ext]' });
  },
};

[haoqunjiang]

As a workaround, always use chainWebpack.

The root cause here is that the merge strategy of webpack-merge (which calls lodash.mergeWith) strips off the private __ruleName property used by webpack-chain to stringify config contents.

https://github.com/mozilla-neutrino/webpack-chain/blob/255b4b5f21c70c4fe83844a3fc5ae1da57526b2b/src/Rule.js#L59-L61

[praburangki]

I had the same issue using this:
configureWebpack: {}

But it works if I change it to this:
configureWebpack: config => {}

@yyx990803 I believe this commit 2257034 fixed the issue. Will this be released soon?