test: add nesting tests

README.md

@@ -12,6 +12,8 @@ __Motto of `nano-css` is simple__: *create the smallest possible CSS-in-JS libra
 - __`@media` queries__ and __animation `@keyframes`__ are supported
 - __Auto-prefixes__ your styles
 - Can __extract CSS__ into external style sheet
+- __100% test coverage__ for [recommended setup](./docs/Installation.md#recommended-setup)
+- __Public domain__ — [Unlicense license](./LICENSE)
 
 
 ## Reference
@@ -56,20 +58,6 @@ __Motto of `nano-css` is simple__: *create the smallest possible CSS-in-JS libra
 - [Server-side rendering](./docs/SSR.md)
 
 
-## Installation
-
-<pre>
-npm i <a href="https://www.npmjs.com/package/nano-css">nano-css</a> --save
-</pre>
-
-Read more about [*Installation*](./docs/Installation.md).
-
-
-## License
-
-[Unlicense](./LICENSE) &mdash; public domain.
-
-
 [npm-url]: https://www.npmjs.com/package/nano-css
 [npm-badge]: https://img.shields.io/npm/v/nano-css.svg
 [travis-url]: https://travis-ci.org/streamich/nano-css

addon/__tests__/nesting.test.js

@@ -0,0 +1,47 @@
+/* eslint-disable */
+'use strict';
+
+var env = require('./env');
+var create = require('../../index').create;
+var addonNesting = require('../../addon/nesting').addon;
+
+function createNano (config) {
+    var nano = create(config);
+
+    addonNesting(nano);
+
+    return nano;
+};
+
+describe('nesting', function () {
+    it('installs without crashing', function () {
+        var nano = createNano();
+    });
+
+    it('prepends selectors if no & operand', function () {
+        var nano = createNano();
+
+        nano.putRaw = jest.fn();
+
+        nano.put('.foo', {
+            '.one,.two': {
+                color: 'tomato'
+            }
+        });
+
+        expect(nano.putRaw.mock.calls[0][0].includes('.foo .one,.foo .two')).toBe(true);
+    });
+/*
+    it('expands & operand after', () => {
+        expect(interpolateSelectors(['.one', '#two'], '.test &')).toBe('.test .one,.test #two');
+    });
+
+    it('expands & operand before', () => {
+        expect(interpolateSelectors(['.test'], '&:hover')).toBe('.test:hover');
+    });
+
+    it('expands & operand before and preserves spaces', () => {
+        expect(interpolateSelectors(['.one', '.two'], '& .test')).toBe('.one .test,.two .test');
+    });
+    */
+});

addon/validate.js

@@ -10,7 +10,7 @@ exports.addon = function (renderer) {
     if (process.env.NODE_ENV === 'production') {
         console.warn(
             'You are using nano-css "validate" in production. ' +
-            'This addon is suggested to be used only in development.'
+            'This addon is meant to be used only in development.'
         );
     }
 

package.json

@@ -38,7 +38,8 @@
     "fastest-stable-stringify": "^1.0.1",
     "stylis": "3.5.0",
     "inline-style-prefixer": "^4.0.0",
-    "rtl-css-js": "^1.9.0"
+    "rtl-css-js": "^1.9.0",
+    "csstree-validator": "^1.3.1"
   },
   "devDependencies": {
     "@types/react": "16.0.40",