pkg: Fix bug #275

Bug:

  Node.js v4 does not support the ES6 syntax fully, thus we
  get the error:

    Block scoped declarations (let, const, function,class) not yet
    supported outside strict mode

Fix:

  * Load transpiled code
  * Deprecate support for Node.js v4.x

References:

  * Bug report: #275
  * PR: #280
  * Reported-by: @CrazyAbdul
  * PR-by: @CrazyAbdul

index.js

@@ -1,12 +1,12 @@
 /**
- * If running on Nodejs 0.12, we load the transpiled code.
+ * If running on Nodejs 4.x and below, we load the transpiled code.
  * Otherwise, we use the ES6 code.
- * We are deprecating support for Node.js v0.x
+ * We are deprecating support for Node.js v4.x and below.
  */
-const majorVersion = process.versions.node.split('.')[0];
-if (majorVersion === '0') {
+const majorVersion = parseInt(process.versions.node.split('.')[0], 10);
+if (majorVersion <= 4) {
   const deprecate = require('depd')('node-telegram-bot-api');
-  deprecate('Node.js v0.12 and below will no longer be supported in the future');
+  deprecate('Node.js v4.x and below will no longer be supported in the future');
   module.exports = require('./lib/telegram');
 } else {
   module.exports = require('./src/telegram');

test/telegram.js

@@ -44,12 +44,13 @@ before(function beforeAll() {
 
 
 describe('module.exports', function moduleExportsSuite() {
-  it('is loaded from src/ if NOT on Node.js 0.12', function test() {
-    if (process.versions.node.split('.')[0] === '0') this.skip(); // skip on Node.js v0.12
+  const nodeVersion = parseInt(process.versions.node.split('.')[0], 10);
+  it('is loaded from src/ on Node.js v5+', function test() {
+    if (nodeVersion <= 4) this.skip(); // skip on Node.js v4 and below
     assert.equal(TelegramBot, require('../src/telegram'));
   });
-  it('is loaded from lib/ if on Node.js 0.12', function test() {
-    if (process.versions.node.split('.')[0] !== '0') this.skip(); // skip on newer versions
+  it('is loaded from lib/ on Node.js v4 and below', function test() {
+    if (nodeVersion > 4) this.skip(); // skip on newer versions
     assert.equal(TelegramBot, require('../lib/telegram'));
   });
 });