Add Drone.io support

ci-services/drone.js

@@ -0,0 +1,27 @@
+'use strict'
+
+const env = process.env
+
+/**
+ * Should update the `package-lock.json`
+ */
+function shouldUpdate () {
+  let re = /^(chore|fix)\(package\): update [^ ]+ to version.*$/mi
+  return re.test(env.DRONE_COMMIT_MESSAGE)
+}
+
+module.exports = {
+  // The GitHub repo slug
+  repoSlug: env.DRONE_REPO,
+  // The name of the current branch
+  branchName: env.DRONE_COMMIT_BRANCH,
+  // Is this the first push on this branch
+  // i.e. the Greenkeeper commit
+  firstPush: shouldUpdate(),
+  // Is this a regular build
+  correctBuild: env.DRONE_BUILD_EVENT === 'push',
+  // Should the lockfile be uploaded from this build
+  uploadBuild: env.DRONE_JOB_NUMBER.endsWith('1'),
+  // The git url
+  gitUrl: env.DRONE_REMOTE_URL
+}

ci-services/tests.js

@@ -5,6 +5,7 @@ const env = process.env
 module.exports = {
   buildkite: () => env.BUILDKITE === 'true',
   circleci: () => env.CIRCLECI === 'true',
+  drone: () => env.DRONE === 'true',
   jenkins: () => env.JENKINS_URL !== undefined,
   travis: () => env.TRAVIS === 'true',
   wercker: () => env.WERCKER === 'true',