Tweak ESLint to better understand Flow (#261)

Author: gaearon

config/eslint.js

@@ -22,7 +22,7 @@ module.exports = {
   parser: 'babel-eslint',
 
   // import plugin is termporarily disabled, scroll below to see why
-  plugins: ['react'/*, 'import'*/, 'jsx-a11y'],
+  plugins: [/*'import', */'flow-vars', 'jsx-a11y', 'react'],
 
   env: {
     browser: true,
@@ -195,6 +195,10 @@ module.exports = {
     'jsx-a11y/aria-role': 'warn',
     'jsx-a11y/img-has-alt': 'warn',
     'jsx-a11y/img-redundant-alt': 'warn',
-    'jsx-a11y/no-access-key': 'warn'
+    'jsx-a11y/no-access-key': 'warn',
+
+    // https://github.com/zertosh/eslint-plugin-flow-vars
+    'flow-vars/define-flow-type': 'warn',
+    'flow-vars/use-flow-type': 'warn'
   }
 };

package.json

@@ -46,6 +46,7 @@
     "detect-port": "0.1.4",
     "eslint": "3.1.1",
     "eslint-loader": "1.4.1",
+    "eslint-plugin-flow-vars": "0.5.0",
     "eslint-plugin-import": "1.12.0",
     "eslint-plugin-jsx-a11y": "2.0.1",
     "eslint-plugin-react": "5.2.2",

template/README.md

@@ -257,7 +257,7 @@ If you don’t need ESLint integration with your editor, you can safely delete t
 Finally, you will need to install some packages *globally*:
 
 ```sh
-npm install -g eslint babel-eslint eslint-plugin-react eslint-plugin-import eslint-plugin-jsx-a11y
+npm install -g eslint babel-eslint eslint-plugin-react eslint-plugin-import eslint-plugin-jsx-a11y eslint-plugin-flow-vars
 ```
 
 We recognize that this is suboptimal, but it is currently required due to the way we hide the ESLint dependency. The ESLint team is already [working on a solution to this](https://github.com/eslint/eslint/issues/3458) so this may become unnecessary in a couple of months.