rewrite Github Languages, split into [githubcodesize githublanguagecount githubtoplanguage] (#3225)

services/github/github-language-count.tester.js

@@ -0,0 +1,21 @@
+'use strict'
+
+const Joi = require('joi')
+const t = (module.exports = require('../tester').createServiceTester())
+
+t.create('language count')
+  .get('/badges/shields.json')
+  .expectBadge({
+    label: 'languages',
+    message: Joi.number()
+      .integer()
+      .positive(),
+  })
+
+t.create('language count (empty repo)')
+  .get('/pyvesb/emptyrepo.json')
+  .expectBadge({ label: 'languages', message: '0' })
+
+t.create('language count (repo not found)')
+  .get('/badges/helmets.json')
+  .expectBadge({ label: 'languages', message: 'repo not found' })