feat: support formatjs eslint rules (#516)

This adds support for formatjs eslint rules, and
adds an `eslint-next`config which includes a rule
that ensures all translation source strings have
descriptions.

config/.eslintrc.next.js

@@ -0,0 +1,48 @@
+// This file will be removed and replace "eslintrc.js" once all MFEs are ready
+const { babel } = require('../lib/presets');
+
+module.exports = {
+  plugins: ['formatjs'],
+  extends: '@edx/eslint-config',
+  parser: '@babel/eslint-parser',
+  parserOptions: {
+    requireConfigFile: true,
+    babelOptions: {
+      configFile: babel.resolvedFilepath || babel.defaultFilepath,
+    },
+  },
+  rules: {
+    'import/no-extraneous-dependencies': [
+      'error',
+      {
+        devDependencies: [
+          '**/*.config.*',
+          '**/*.test.*',
+          '**/setupTest.js',
+        ],
+      },
+    ],
+    'import/no-unresolved': [
+      'error',
+      {
+        ignore: [
+          'env.config',
+        ],
+      },
+    ],
+    // https://github.com/evcohen/eslint-plugin-jsx-a11y/issues/340#issuecomment-338424908
+    'jsx-a11y/anchor-is-valid': ['error', {
+      components: ['Link'],
+      specialLink: ['to'],
+    }],
+    'formatjs/enforce-description': ['error', 'literal'],
+    'import/no-import-module-export': 'off',
+    'react/function-component-definition': [2, { namedComponents: 'arrow-function' }],
+  },
+  globals: {
+    newrelic: false,
+  },
+  ignorePatterns: [
+    'module.config.js',
+  ],
+};

lib/presets.js

@@ -32,6 +32,13 @@ const eslint = new ConfigPreset({
   searchFilepaths,
 });
 
+// This will be removed and replace "eslint" once all MFEs are ready
+const eslintNext = new ConfigPreset({
+  defaultFilename: '.eslintrc.next.js',
+  searchFilenames: ['.eslintrc.next', '.eslintrc.next.js'],
+  searchFilepaths,
+});
+
 const jest = new ConfigPreset({
   defaultFilename: 'jest.config.js',
   searchFilenames: ['jest.config.js'],
@@ -63,6 +70,7 @@ module.exports = {
   'babel-preserve-modules': babelPreserveModules,
   'babel-typescript': babelTypescript,
   eslint,
+  'eslint-next': eslintNext, // This will be removed and replace "eslint" once all MFEs are ready
   jest,
   webpack,
   webpackDevServer,