feat: allow require for configs (#72)

With this PR linting skips prefer import rules for .config.js files, root or nested.

This removes the need to manually ignore these rules on common configuration files.

README.md

@@ -40,7 +40,7 @@ Then enhance it with one or more **addons**:
 
 - `browser` - If you are going to develop code for the browser (assumes you use CommonJS or AMD)
 - `node` - If you are going to develop code for [NodeJS](nodejs.org)
-- `es-modules`: If you are going to use ES6 import & export instead of CommonJS or AMD
+- `es-modules`: If you are going to use ES6 import & export instead of CommonJS or AMD (this rule skips root `[...].config.js` files to avoid ignoring this rule in common configuration files)
 - `babel-parser`: Use [babel-eslint](https://github.com/babel/babel-eslint) parser so that you may use language features that are not yet implemented in eslint (e.g.: dynamic imports)
 - `react` - If you are going to use [React](https://reactjs.org/) (requires `es6` base configuration or higher)
 - `jest` - If you are going to use [Jest](https://facebook.github.io/jest/) to develop tests

addons/es-modules.js

@@ -15,4 +15,10 @@ module.exports = {
         // comment: This should be a warning instead of an error because there are still cases when we must use require.
         'prefer-import/prefer-import-over-require': 1,
     },
+    'overrides': [{
+        'files': '*.config.js',
+        'rules': {
+            'prefer-import/prefer-import-over-require': 0,
+        },
+    }],
 };

test/__snapshots__/index.spec.js.snap

@@ -1769,6 +1769,19 @@ Array [
 
 exports[`should pass on fixtures/samples/es6-modules/contrived.good.js 1`] = `Array []`;
 
+exports[`should pass on fixtures/samples/es6-modules/require.config.js 1`] = `Array []`;
+
+exports[`should pass on fixtures/samples/es6-modules/require.js 1`] = `
+Array [
+  Object {
+    "column": 14,
+    "line": 5,
+    "rule": "prefer-import/prefer-import-over-require",
+    "severity": 1,
+  },
+]
+`;
+
 exports[`should pass on fixtures/samples/es6-node/fileSize.good.js 1`] = `Array []`;
 
 exports[`should pass on fixtures/samples/es6-node/loudException.good.js 1`] = `Array []`;

test/fixtures/samples/es6-modules/require.config.js

@@ -0,0 +1,7 @@
+// Made up sample.. not genuine
+
+// [...].config.js file, should not warn against require
+
+const test = require('good');
+
+console.log(test);

test/fixtures/samples/es6-modules/require.js

@@ -0,0 +1,7 @@
+// Made up sample.. not genuine
+
+// Common file, should warn against require
+
+const test = require('bad');
+
+console.log(test);