Allow to use @vue/component to set type of file to vue

fixes #109

Author: armano2

lib/utils/index.js

@@ -341,6 +341,16 @@ module.exports = {
       })
   },
 
+  /**
+   * Check whether the given node is a Vue component based
+   * @param {RuleContext} context The ESLint rule context object.
+   * @returns {boolean}
+   */
+  hasVueComponentComment (context) {
+    const sourceCode = context.getSourceCode()
+    return Boolean(sourceCode.getAllComments().find(item => /@vue\/component/g.test(item.value)))
+  },
+
   /**
    * Check whether the given node is a Vue component based
    * on the filename and default export type
@@ -435,8 +445,8 @@ module.exports = {
 
     return {
       'ExportDefaultDeclaration:exit' (node) {
-        // export default {} in .vue || .jsx
-        if (!_this.isVueComponentFile(node, filePath)) return
+        // export default {} in .vue || .jsx or comment with @vue/component
+        if (!_this.isVueComponentFile(node, filePath, context) && !_this.hasVueComponentComment(context)) return
         cb(node.declaration)
       },
       'CallExpression:exit' (node) {

tests/lib/rules/require-render-return.js

@@ -88,6 +88,35 @@ ruleTester.run('require-render-return', rule, {
         }
       }`,
       parserOptions
+    },
+    {
+      code: `/* @vue/component */
+      export default {
+        render() {
+          return {}
+        }
+      })`,
+      parserOptions
+    },
+    {
+      code: `// @vue/component
+      export default {
+        render() {
+          return {}
+        }
+      })`,
+      parserOptions
+    },
+    {
+      code: `/**
+       * @vue/component
+       */
+      export default {
+        render() {
+          return {}
+        }
+      })`,
+      parserOptions
     }
   ],
 
@@ -119,6 +148,51 @@ ruleTester.run('require-render-return', rule, {
         type: 'Identifier',
         line: 2
       }]
+    },
+    {
+      code: `
+      /* @vue/component */
+      export default {
+        render() {
+        }
+      }`,
+      parserOptions,
+      errors: [{
+        message: 'Expected to return a value in render function.',
+        type: 'Identifier',
+        line: 3
+      }]
+    },
+    {
+      code: `
+      // @vue/component
+      export default {
+        render() {
+        }
+      }`,
+      parserOptions,
+      errors: [{
+        message: 'Expected to return a value in render function.',
+        type: 'Identifier',
+        line: 3
+      }]
+    },
+    {
+      code: `
+      /**
+       * @vue/component
+       */
+      export default {
+        render() {
+          return
+        }
+      })`,
+      parserOptions,
+      errors: [{
+        message: 'Expected to return a value in render function.',
+        type: 'Identifier',
+        line: 3
+      }]
     }
   ]
 })