Add React.PureComponent support to require-optimization rule

Author: yannickcr

lib/rules/require-optimization.js

@@ -5,6 +5,7 @@
 'use strict';
 
 var Components = require('../util/Components');
+var pragmaUtil = require('../util/pragma');
 
 module.exports = {
   meta: {
@@ -33,6 +34,10 @@ module.exports = {
     var configuration = context.options[0] || {};
     var allowDecorators = configuration.allowDecorators || [];
 
+    var pragma = pragmaUtil.getFromContext(context);
+    var pureComponentRegExp = new RegExp('^(' + pragma + '\\.)?PureComponent$');
+    var sourceCode = context.getSourceCode();
+
     /**
      * Checks to see if our component is decorated by PureRenderMixin via reactMixin
      * @param {ASTNode} node The AST node being checked.
@@ -84,6 +89,19 @@ module.exports = {
       return false;
     };
 
+    /**
+     * Checks to see if our component extends React.PureComponent
+     * @param {ASTNode} node The AST node being checked.
+     * @returns {Boolean} True if node extends React.PureComponent, false if not.
+     */
+    var isPureComponent = function (node) {
+      if (node.superClass) {
+        return pureComponentRegExp.test(sourceCode.getText(node.superClass));
+      }
+
+      return false;
+    };
+
     /**
      * Checks if we are declaring a shouldComponentUpdate method
      * @param {ASTNode} node The AST node being checked.
@@ -150,7 +168,7 @@ module.exports = {
       },
 
       ClassDeclaration: function (node) {
-        if (!(hasPureRenderDecorator(node) || hasCustomDecorator(node))) {
+        if (!(hasPureRenderDecorator(node) || hasCustomDecorator(node) || isPureComponent(node))) {
           return;
         }
         markSCUAsDeclared(node);

tests/lib/rules/require-optimization.js

@@ -96,6 +96,22 @@ ruleTester.run('react-require-optimization', rule, {
     parser: 'babel-eslint',
     options: [{allowDecorators: ['renderPure', 'pureRender']}],
     parserOptions: parserOptions
+  }, {
+    code: [
+      'import React from "react";' +
+      'class YourComponent extends React.PureComponent {}'
+    ].join('\n'),
+    parser: 'babel-eslint',
+    options: [{allowDecorators: ['renderPure', 'pureRender']}],
+    parserOptions: parserOptions
+  }, {
+    code: [
+      'import React, {PureComponent} from "react";' +
+      'class YourComponent extends PureComponent {}'
+    ].join('\n'),
+    parser: 'babel-eslint',
+    options: [{allowDecorators: ['renderPure', 'pureRender']}],
+    parserOptions: parserOptions
   }],
 
   invalid: [{