Prevent data leakage in no-dupe-keys rule (#317)

Author: michalsnik

Diff for: lib/rules/no-dupe-keys.js

@@ -13,8 +13,6 @@ const utils = require('../utils')
 const GROUP_NAMES = ['props', 'computed', 'data', 'methods']
 
 function create (context) {
-  const usedNames = []
-
   const options = context.options[0] || {}
   const groups = new Set(GROUP_NAMES.concat(options.groups || []))
 
@@ -23,7 +21,9 @@ function create (context) {
   // ----------------------------------------------------------------------
 
   return utils.executeOnVue(context, (obj) => {
+    const usedNames = []
     const properties = utils.iterateProperties(obj, groups)
+
     for (const o of properties) {
       if (usedNames.indexOf(o.name) !== -1) {
         context.report({
@@ -34,6 +34,7 @@ function create (context) {
           }
         })
       }
+
       usedNames.push(o.name)
     }
   })

Diff for: tests/lib/rules/no-dupe-keys.js

@@ -80,6 +80,26 @@ ruleTester.run('no-dupe-keys', rule, {
         }
       `,
       parserOptions: { ecmaVersion: 8, sourceType: 'module', ecmaFeatures: { experimentalObjectRestSpread: true }}
+    },
+
+    {
+      filename: 'test.js',
+      code: `
+        // @vue/component
+        export const compA = {
+          props: {
+            propA: String
+          }
+        }
+
+        // @vue/component
+        export const compB = {
+          props: {
+            propA: String
+          }
+        }
+      `,
+      parserOptions: { ecmaVersion: 6, sourceType: 'module' }
     }
   ],