Why does 'vue-cli-service build' fail after creating a new eslint-plugin, with error 'TypeError: eslint.CLIEngine is not a constructor'? - vue.js

Question

After creating a new eslint-plugin for a custom rule, vue-cli-service build fails (eslint works as expected, when triggered by ./node_modules/.bin/eslint --ext .js,.vue,.json ./ --max-warnings=0).
GitHub repository reproducing issue
Starting in an environment with a working vue-cli-service build, following the simplified instructions at https://blog.webiny.com/create-custom-eslint-rules-in-2-minutes-e3d41cb6a9a0, also reproduces the issue. Running vue-cli-service build after every step, it starts failing after step 4: yarn add --dev file:./eslint, and the build still fails after all the steps are completed.
Error message:
ERROR Failed to compile with 32 errors
Module build failed (from ./node_modules/#vue/cli-plugin-eslint/node_modules/eslint-loader/index.js):
TypeError: eslint.CLIEngine is not a constructor
at Object.module.exports (MYPATH/node_modules/#vue/cli-plugin-eslint/node_modules/eslint-loader/index.js:223:27)
***repeats 31 more times***
You may use special comments to disable some warnings.
Use // eslint-disable-next-line to ignore the next line.
Use /* eslint-disable */ to ignore all warnings in a file.
ERROR Build failed with errors.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
vue-cli-service build stills fails after running yarn install, which says it is already up to date.
Most results for this specific TypeError: eslint.CLIEngine is not a constructor error claim the user should upgrade their JetBrains IDE. However, I am running vue-cli-service build on the command line and not using JetBrains.
The code referred to by the error message is (with preceding context):
MYPATH/node_modules/#vue/cli-plugin-eslint/node_modules/eslint-loader/index.js
...
var config = assign(
// loader defaults
{
cacheIdentifier: JSON.stringify({
"eslint-loader": pkg.version,
eslint: eslintVersion || "unknown version"
}),
eslintPath: "eslint"
},
userOptions
);
if (typeof config.formatter === "string") {
try {
config.formatter = require(config.formatter);
if (
config.formatter &&
typeof config.formatter !== "function" &&
typeof config.formatter.default === "function"
) {
config.formatter = config.formatter.default;
}
} catch (_) {
// ignored
}
}
var cacheDirectory = config.cache;
var cacheIdentifier = config.cacheIdentifier;
delete config.cacheIdentifier;
// Create the engine only once per config
var configHash = objectHash(config);
if (!engines[configHash]) {
var eslint = require(config.eslintPath);
engines[configHash] = new eslint.CLIEngine(config); //Error happens here
}
...
Edit: I upgraded #vue/cli-plugin-eslint from version 3.11.0 to 4.1.2 by editing yarn's package.json, at the suggestion of #DelenaMalan below. The build still fails with error:
ERROR Failed to compile with 1 errors 7:51:01 PM
Module build failed (from ./node_modules/#vue/cli-service/node_modules/thread-loader/dist/cjs.js):
Thread Loader (Worker 0)
eslint.CLIEngine is not a constructor
at PoolWorker.fromErrorObj (MYPATH/node_modules/#vue/cli-service/node_modules/thread-loader/dist/WorkerPool.js:262:12)
at MYPATH/node_modules/#vue/cli-service/node_modules/thread-loader/dist/WorkerPool.js:204:29
at mapSeries (MYPATH/node_modules/neo-async/async.js:3625:14)
at PoolWorker.onWorkerMessage (MYPATH/node_modules/#vue/cli-service/node_modules/thread-loader/dist/WorkerPool.js:170:35)
at readBuffer (MYPATH/node_modules/#vue/cli-service/node_modules/thread-loader/dist/WorkerPool.js:152:14)
at Object.module.exports (MYPATH/node_modules/#vue/cli-plugin-eslint/node_modules/eslint-loader/index.js:223:27)
You may use special comments to disable some warnings.
Use // eslint-disable-next-line to ignore the next line.
Use /* eslint-disable */ to ignore all warnings in a file.
ERROR Build failed with errors.
error Command failed with exit code 1.
Edit 2:
I deleted and reinstalled the node modules on the repro linked here, as recommended by #CGundlach, but I still have the eslint.CLIEngine is not a constructor error
Annas-MacBook-Pro:eslint-test-project anna$ rm -rf node_modules/
Annas-MacBook-Pro:eslint-test-project anna$ yarn install
yarn install v1.21.1
[1/4] 🔍 Resolving packages...
[2/4] 🚚 Fetching packages...
[3/4] 🔗 Linking dependencies...
warning "#vue/eslint-config-airbnb > eslint-import-resolver-webpack#0.11.1" has unmet peer dependency "webpack#>=1.11.0".
[4/4] 🔨 Building fresh packages...
✨ Done in 14.14s.
Annas-MacBook-Pro:eslint-test-project anna$ yarn build
yarn run v1.21.1
$ vue-cli-service build
⠏ Building for production...
ERROR Failed to compile with 1 errors 12:28:32 PM
Module build failed (from ./node_modules/thread-loader/dist/cjs.js):
Thread Loader (Worker 0)
eslint.CLIEngine is not a constructor
at PoolWorker.fromErrorObj (/Users/anna/projects/yarn-vue-eslint/eslint-test-project/node_modules/thread-loader/dist/WorkerPool.js:262:12)
at /Users/anna/projects/yarn-vue-eslint/eslint-test-project/node_modules/thread-loader/dist/WorkerPool.js:204:29
at mapSeries (/Users/anna/projects/yarn-vue-eslint/eslint-test-project/node_modules/neo-async/async.js:3625:14)
at PoolWorker.onWorkerMessage (/Users/anna/projects/yarn-vue-eslint/eslint-test-project/node_modules/thread-loader/dist/WorkerPool.js:170:35)
at readBuffer (/Users/anna/projects/yarn-vue-eslint/eslint-test-project/node_modules/thread-loader/dist/WorkerPool.js:152:14)
at Object.module.exports (/Users/anna/projects/yarn-vue-eslint/eslint-test-project/node_modules/eslint-loader/index.js:223:27)
You may use special comments to disable some warnings.
Use // eslint-disable-next-line to ignore the next line.
Use /* eslint-disable */ to ignore all warnings in a file.
ERROR Build failed with errors.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

Answer 1

Make sure all warnings are resolved when you run either npm ci, npm i or yarn install. For me the following warnings were showed after doing a fresh install:
$ vue-cli-service build
⠧ Building for production...
ERROR Failed to compile with 1 error 20:47:55
Syntax Error: Thread Loader (Worker 0)
eslint.CLIEngine is not a constructor
You may use special comments to disable some warnings.
Use // eslint-disable-next-line to ignore the next line.
Use /* eslint-disable */ to ignore all warnings in a file.
When I did a fresh install and resolved the peer dependency issue by decreasing my eslint version everything works as expected.
So try to downgrade your eslint dependency to the correct version. For me I had to downgrade to eslint < 7.0.0.
npm i -D eslint#6.8.0
# or yarn
yarn add -D eslint#6.8.0