chore!: update eslint-loader, minimum supported ESLint version is 6 (#5870)

Author: haoqunjiang

docs/migrations/migrate-from-v4.md

@@ -38,6 +38,10 @@ If you want to migrate manually and gradually, you can run `vue upgrade <the-plu
 
 ### The Global `@vue/cli` and The `vue` Command
 
+### `@vue/cli-plugin-eslint`
+
+* `eslint-loader` is upgraded [from v2 to v4](https://github.com/webpack-contrib/eslint-loader/blob/master/CHANGELOG.md). The only major change is that it dropped support for ESLint < v6.
+
 ### `@vue/cli-plugin-typescript`
 
 #### Dropped TSLint support

packages/@vue/cli-plugin-eslint/__tests__/eslintMigrator.spec.js

@@ -1,8 +1,6 @@
 jest.setTimeout(300000)
-jest.mock('inquirer')
 
 const create = require('@vue/cli-test-utils/createUpgradableProject')
-const { expectPrompts } = require('inquirer')
 
 test('upgrade: should add eslint to devDependencies', async () => {
   const project = await create('plugin-eslint-v3.0', {
@@ -16,17 +14,10 @@ test('upgrade: should add eslint to devDependencies', async () => {
   const pkg = JSON.parse(await project.read('package.json'))
   expect(pkg.devDependencies).not.toHaveProperty('eslint')
 
-  expectPrompts([
-    {
-      message: `Your current ESLint version is v4`,
-      confirm: false
-    }
-  ])
-
   await project.upgrade('eslint')
 
   const updatedPkg = JSON.parse(await project.read('package.json'))
-  expect(updatedPkg.devDependencies.eslint).toMatch('^4')
+  expect(updatedPkg.devDependencies.eslint).toMatch('^6')
 })
 
 test('upgrade: should upgrade eslint from v5 to v6', async () => {
@@ -42,13 +33,6 @@ test('upgrade: should upgrade eslint from v5 to v6', async () => {
   const pkg = JSON.parse(await project.read('package.json'))
   expect(pkg.devDependencies.eslint).toMatch('^5')
 
-  expectPrompts([
-    {
-      message: `Your current ESLint version is v5`,
-      confirm: true
-    }
-  ])
-
   try {
     await project.upgrade('eslint')
   } catch (e) {

packages/@vue/cli-plugin-eslint/migrator/index.js

@@ -1,4 +1,3 @@
-const inquirer = require('inquirer')
 const { semver } = require('@vue/cli-shared-utils')
 
 module.exports = async (api) => {
@@ -32,44 +31,35 @@ module.exports = async (api) => {
     return
   }
 
-  const { confirmUpgrade } = await inquirer.prompt([{
-    name: 'confirmUpgrade',
-    type: 'confirm',
-    message:
-    `Your current ESLint version is v${localESLintMajor}.\n` +
-    `The latest major version which supported by vue-cli is v6.\n` +
-    `Do you want to upgrade? (May contain breaking changes)\n`
-  }])
+  const { getDeps } = require('../eslintDeps')
 
-  if (confirmUpgrade) {
-    const { getDeps } = require('../eslintDeps')
-
-    const newDeps = getDeps(api)
-    if (pkg.devDependencies['@vue/eslint-config-airbnb']) {
-      Object.assign(newDeps, getDeps(api, 'airbnb'))
-    }
-    if (pkg.devDependencies['@vue/eslint-config-standard']) {
-      Object.assign(newDeps, getDeps(api, 'standard'))
-    }
-    if (pkg.devDependencies['@vue/eslint-config-prettier']) {
-      Object.assign(newDeps, getDeps(api, 'prettier'))
-    }
+  const newDeps = getDeps(api)
+  if (pkg.devDependencies['@vue/eslint-config-airbnb']) {
+    Object.assign(newDeps, getDeps(api, 'airbnb'))
+  }
+  if (pkg.devDependencies['@vue/eslint-config-standard']) {
+    Object.assign(newDeps, getDeps(api, 'standard'))
+  }
+  if (pkg.devDependencies['@vue/eslint-config-prettier']) {
+    Object.assign(newDeps, getDeps(api, 'prettier'))
+  }
 
-    api.extendPackage({ devDependencies: newDeps }, { warnIncompatibleVersions: false })
+  api.extendPackage({ devDependencies: newDeps }, { warnIncompatibleVersions: false })
 
-    // in case anyone's upgrading from the legacy `typescript-eslint-parser`
-    if (api.hasPlugin('typescript')) {
-      api.extendPackage({
-        eslintConfig: {
-          parserOptions: {
-            parser: '@typescript-eslint/parser'
-          }
+  // in case anyone's upgrading from the legacy `typescript-eslint-parser`
+  if (api.hasPlugin('typescript')) {
+    api.extendPackage({
+      eslintConfig: {
+        parserOptions: {
+          parser: '@typescript-eslint/parser'
         }
-      })
-    }
-
-    // TODO:
-    // transform `@vue/prettier` to `eslint:recommended` + `@vue/prettier`
-    // transform `@vue/typescript` to `@vue/typescript/recommended` and also fix prettier compatibility for it
+      }
+    })
   }
+
+  api.exitLog(`ESLint upgraded from v${localESLintMajor}. to v6\n`)
+
+  // TODO:
+  // transform `@vue/prettier` to `eslint:recommended` + `@vue/prettier`
+  // transform `@vue/typescript` to `@vue/typescript/recommended` and also fix prettier compatibility for it
 }

packages/@vue/cli-plugin-eslint/package.json

@@ -24,14 +24,14 @@
   },
   "dependencies": {
     "@vue/cli-shared-utils": "^4.5.5",
-    "eslint-loader": "^2.2.1",
+    "eslint-loader": "^4.0.2",
     "globby": "^9.2.0",
     "inquirer": "^7.1.0",
     "webpack": "^4.0.0",
     "yorkie": "^2.0.0"
   },
   "peerDependencies": {
     "@vue/cli-service": "^3.0.0 || ^4.0.0-0",
-    "eslint": ">= 1.6.0"
+    "eslint": ">= 6.0.0"
   }
 }

packages/@vue/cli-service-global/package.json

@@ -28,8 +28,8 @@
     "babel-eslint": "^10.1.0",
     "chalk": "^4.1.0",
     "core-js": "^3.6.5",
-    "eslint": "^5.16.0",
-    "eslint-plugin-vue": "^5.2.2",
+    "eslint": "^6.7.2",
+    "eslint-plugin-vue": "^6.2.2",
     "regenerator-runtime": "^0.13.5",
     "resolve": "^1.17.0",
     "vue": "^2.6.12",