feat(rule): no commonjs api in nuxt config

Author: clarkdo

README.md

@@ -83,6 +83,7 @@ This plugin provides four predefined configs:
 |  | [nuxt/no-env-in-hooks](./docs/rules/no-env-in-hooks.md) | Disallow `process.server/process.client` in client only Vue lifecycle hooks like: `mounted, beforeMount, updated...` |
 |  | [nuxt/no-globals-in-created](./docs/rules/no-globals-in-created.md) | Disallow `window/document` in `created/beforeCreate` |
 |  | [nuxt/no-this-in-fetch-data](./docs/rules/no-this-in-fetch-data.md) | Disallow `this` in `asyncData/fetch` |
+|  | [nuxt/no-cjs-in-config](./docs/rules/no-cjs-in-config.md) | Disallow `require/modules.exports/exports` in `nuxt.config.js` |
 
 ### Recommended Rules
 

docs/rules/no-cjs-in-config.md

@@ -0,0 +1,40 @@
+# nuxt/no-cjs-in-config
+
+> Disallow commonjs module api `require/modules.exports/exports` in `nuxt.config.js`
+
+- :gear: This rule is included in `"plugin:nuxt/base"`.
+
+## Rule Details
+
+This rule is for preventing using `require/modules.exports/exportst` in `nuxt.config.js`
+
+Examples of **incorrect** code for this rule:
+
+```js
+
+const { name } = require('./package.json')
+
+module.exports = {
+  mode: 'universal',
+  name
+}
+
+```
+
+Examples of **correct** code for this rule:
+
+```js
+
+import { name } from './package.json'
+
+export default {
+  mode: 'universal',
+  name
+}
+
+```
+
+## :mag: Implementation
+
+- [Rule source](../../lib/rules/no-cjs-in-config.js)
+- [Test source](../../lib/rules/__test__/no-cjs-in-config.test.js)

lib/configs/base.js

@@ -18,6 +18,7 @@ module.exports = {
     'nuxt/no-env-in-context': 'error',
     'nuxt/no-env-in-hooks': 'error',
     'nuxt/no-globals-in-created': 'error',
-    'nuxt/no-this-in-fetch-data': 'error'
+    'nuxt/no-this-in-fetch-data': 'error',
+    'nuxt/no-cjs-in-config': 'error'
   }
 }

lib/index.js

@@ -4,7 +4,8 @@ module.exports = {
     'no-env-in-hooks': require('./rules/no-env-in-hooks'),
     'no-globals-in-created': require('./rules/no-globals-in-created'),
     'no-this-in-fetch-data': require('./rules/no-this-in-fetch-data'),
-    'no-timing-in-fetch-data': require('./rules/no-timing-in-fetch-data')
+    'no-timing-in-fetch-data': require('./rules/no-timing-in-fetch-data'),
+    'no-cjs-in-config': require('./rules/no-cjs-in-config')
   },
   configs: {
     'base': require('./configs/base'),

lib/rules/__test__/no-cjs-in-config.test.js

@@ -0,0 +1,83 @@
+/**
+ * @fileoverview Disallow `require/modules.exports/exports` in `nuxt.config.js`
+ * @author Xin Du <clark.duxin@gmail.com>
+ */
+'use strict'
+
+// ------------------------------------------------------------------------------
+// Requirements
+// ------------------------------------------------------------------------------
+
+var rule = require('../no-cjs-in-config')
+
+var RuleTester = require('eslint').RuleTester
+
+const parserOptions = {
+  ecmaVersion: 2018,
+  sourceType: 'module'
+}
+
+// ------------------------------------------------------------------------------
+// Tests
+// ------------------------------------------------------------------------------
+
+var ruleTester = new RuleTester()
+ruleTester.run('no-cjs-in-config', rule, {
+
+  valid: [
+    {
+      filename: 'nuxt.config.js',
+      code: `
+        import { name } from './package.json'
+
+        export default {
+          mode: 'universal',
+          name
+        }
+      `,
+      parserOptions
+    }
+  ],
+
+  invalid: [
+    {
+      filename: 'nuxt.config.js',
+      code: `
+        const { name } = require('./package.json')
+      `,
+      errors: [{
+        message: 'Unexpected require, please use import instead.',
+        type: 'Identifier'
+      }],
+      parserOptions
+    },
+    {
+      filename: 'nuxt.config.js',
+      code: `
+        module.exports = {
+          mode: 'universal',
+          name
+        }
+      `,
+      errors: [{
+        message: 'Unexpected module.exports, please use export default instead.',
+        type: 'MemberExpression'
+      }],
+      parserOptions
+    },
+    {
+      filename: 'nuxt.config.js',
+      code: `
+        exports.test = {
+          mode: 'universal',
+          name
+        }
+      `,
+      errors: [{
+        message: 'Unexpected exports, please use export default instead.',
+        type: 'MemberExpression'
+      }],
+      parserOptions
+    }
+  ]
+})

lib/rules/no-cjs-in-config.js

@@ -0,0 +1,101 @@
+/**
+ * @fileoverview Disallow `require/modules.exports/exports` in `nuxt.config.js`
+ * @author Xin Du <clark.duxin@gmail.com>
+ */
+'use strict'
+
+// ------------------------------------------------------------------------------
+// Rule Definition
+// ------------------------------------------------------------------------------
+
+module.exports = {
+  meta: {
+    docs: {
+      description:
+        'disallow commonjs module api `require/modules.exports/exports` in `nuxt.config.js`',
+      category: 'base'
+    },
+    messages: {
+      noCjs: 'Unexpected {{cjs}}, please use {{esm}} instead.'
+    }
+  },
+
+  create (context) {
+    // variables should be defined here
+    const options = context.options[0] || {}
+    const configFile = options.file || 'nuxt.config.js'
+    let isNuxtConfig = false
+
+    // ----------------------------------------------------------------------
+    // Public
+    // ----------------------------------------------------------------------
+
+    return {
+      Program (node) {
+        const filename = context.getFilename()
+        if (filename === configFile) {
+          isNuxtConfig = true
+        }
+      },
+      MemberExpression: function (node) {
+        if (!isNuxtConfig) {
+          return
+        }
+
+        // module.exports
+        if (node.object.name === 'module' && node.property.name === 'exports') {
+          context.report({
+            node,
+            messageId: 'noCjs',
+            data: {
+              cjs: 'module.exports',
+              esm: 'export default'
+            }
+          })
+        }
+
+        // exports.
+        if (node.object.name === 'exports') {
+          const isInScope = context.getScope()
+            .variables
+            .some(variable => variable.name === 'exports')
+          if (!isInScope) {
+            context.report({
+              node,
+              messageId: 'noCjs',
+              data: {
+                cjs: 'exports',
+                esm: 'export default'
+              }
+            })
+          }
+        }
+      },
+      CallExpression: function (call) {
+        const module = call.arguments[0]
+
+        if (
+          !isNuxtConfig ||
+          context.getScope().type !== 'module' ||
+          !['ExpressionStatement', 'VariableDeclarator'].includes(call.parent.type) ||
+          call.callee.type !== 'Identifier' ||
+          call.callee.name !== 'require' ||
+          call.arguments.length !== 1 ||
+          module.type !== 'Literal' ||
+          typeof module.value !== 'string'
+        ) {
+          return
+        }
+
+        context.report({
+          node: call.callee,
+          messageId: 'noCjs',
+          data: {
+            cjs: 'require',
+            esm: 'import'
+          }
+        })
+      }
+    }
+  }
+}