test: add test for getSpotifyPlaylist

package.json

@@ -4,7 +4,7 @@
   "description": "Download Spotify playlist as mp3 from VKontakte",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "test": "mocha"
   },
   "bin": {
     "vk-music-dl": "./index.js"
@@ -36,5 +36,7 @@
     "node-fetch": "^2.6.0",
     "promisepipe": "^3.0.0"
   },
-  "devDependencies": {}
+  "devDependencies": {
+    "mocha": "^8.1.3"
+  }
 }

test/lib.test.js

@@ -0,0 +1,14 @@
+'use strict';
+const assert = require('assert');
+const {getSpotifyPlaylist} = require('../lib');
+
+describe('getSpotifyPlaylist', function(){
+
+  it('acquire and parse playlist from Spotify', async function(){
+    const playlist = await getSpotifyPlaylist('https://open.spotify.com/playlist/27OFA3NDwoLWtmdMvowA3S');
+    assert.strictEqual(playlist.name, 'The Best Yoga & Cool-Down Songs');
+    assert.strictEqual(playlist.type, 'playlist');
+    assert.strictEqual(playlist.tracks.items.length, 10);
+  });
+
+});