From 2d6181bd68b22f1e7f2c08154aec3974cf6caf3f Mon Sep 17 00:00:00 2001
From: Victor <vb4007@gmail.com>
Date: Mon, 12 Feb 2018 23:15:13 +0100
Subject: [PATCH] feat: detect WIP commit messages (#32)

thanks @Raul6469 & @HeeL
---
 lib/handle-pull-request-change.js | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/lib/handle-pull-request-change.js b/lib/handle-pull-request-change.js
index cc32e1de6..46093de7c 100644
--- a/lib/handle-pull-request-change.js
+++ b/lib/handle-pull-request-change.js
@@ -1,17 +1,29 @@
 module.exports = handlePullRequestChange
 
 async function handlePullRequestChange (robot, context) {
-  const title = context.payload.pull_request.title
-  const isWip = /\b(wip|do not merge)\b/i.test(title)
+  const {title, html_url, head} = context.payload.pull_request
+  const isWip = containsWIP(title) || await commitsContainWIP(context)
   const status = isWip ? 'pending' : 'success'
 
-  console.log(`Updating PR "${title}" (${context.payload.pull_request.html_url}): ${status}`)
+  console.log('Updating PR "%s" (%s): %s', title, html_url, status)
 
   context.github.repos.createStatus(context.repo({
-    sha: context.payload.pull_request.head.sha,
+    sha: head.sha,
     state: status,
     target_url: 'https://github.com/apps/wip',
     description: isWip ? 'work in progress – do not merge!' : 'ready for review',
     context: 'WIP'
   }))
 }
+
+async function commitsContainWIP (context) {
+  const commits = await context.github.pullRequests.getCommits(context.repo({
+    number: context.payload.pull_request.number
+  }))
+
+  return commits.data.map(element => element.commit.message).some(containsWIP)
+}
+
+function containsWIP (string) {
+  return /\b(wip|do not merge)\b/i.test(string)
+}