Add support for heroku CI (#127)

lib/detect.js

@@ -12,6 +12,7 @@ var services = {
   semaphore: require('./services/semaphore'),
   snap: require('./services/snap'),
   gitlab: require('./services/gitlab'),
+  heroku: require('./services/heroku'),
 }
 
 var detectProvider = function() {

lib/services/heroku.js

@@ -0,0 +1,17 @@
+// https://devcenter.heroku.com/articles/heroku-ci
+
+module.exports = {
+  detect: function() {
+    return !!process.env.HEROKU_TEST_RUN_ID
+  },
+
+  configuration: function() {
+    console.log('    heroku CI Detected')
+    return {
+      service: 'heroku',
+      build: process.env.HEROKU_TEST_RUN_ID,
+      commit: process.env.HEROKU_TEST_RUN_COMMIT_VERSION,
+      branch: process.env.HEROKU_TEST_RUN_BRANCH,
+    }
+  },
+}

test/services/heroku.test.js

@@ -0,0 +1,21 @@
+var heroku = require('../../lib/services/heroku')
+
+describe('Heroku CI Provider', function() {
+  it('can detect heroku', function() {
+    process.env.HEROKU_TEST_RUN_ID = '454f5dc9-afa4-433f-bb28-84678a00fd98'
+    expect(heroku.detect()).toBe(true)
+  })
+
+  it('can get wercker env info', function() {
+    process.env.HEROKU_TEST_RUN_ID = '454f5dc9-afa4-433f-bb28-84678a00fd98'
+    process.env.HEROKU_TEST_RUN_COMMIT_VERSION =
+      '743b04806ea677403aa2ff26c6bdeb85005de658'
+    process.env.HEROKU_TEST_RUN_BRANCH = 'master'
+    expect(heroku.configuration()).toEqual({
+      service: 'heroku',
+      commit: '743b04806ea677403aa2ff26c6bdeb85005de658',
+      build: '454f5dc9-afa4-433f-bb28-84678a00fd98',
+      branch: 'master',
+    })
+  })
+})