Revert "Merge pull request nodejs#16 from Fishrock123/no-comment"

This reverts commit 82f4437, reversing
changes made to 8e255d3.

Author: Fishrock123

lib/pollTravis.js

@@ -22,10 +22,77 @@ githubClient.authenticate({
   token: process.env.GITHUB_TOKEN
 })
 
-exports.pollThenStatus = pollByCommitThenStatus
+exports.pollThenStatus = pollThenStatus
+
+function pollThenStatus (owner, repoName, prId) {
+  const prInfo = prInfoStr({ owner, repoName, prId })
+
+  // we have to figure out what type of Travis polling we should perform,
+  // either by PR #id (as for nodejs.org) or commit sha (for readable-stream)
+  travisClient.repos(owner, repoName).builds.get((err, res) => {
+    if (err) {
+      return console.error(`! ${prInfo} Error while retrieving initial builds`, err.stack)
+    }
+
+    const hasAnyPrBuilds = res.builds.some((build) => build.pull_request)
+
+    if (hasAnyPrBuilds) {
+      pollByPrThenComment(owner, repoName, prId)
+    } else {
+      pollByCommitThenStatus(owner, repoName, prId)
+    }
+  })
+}
 
 /**
- * Poll and match builds by the last commit SHA of the related PR.
+ * When Travis CI picks up our PR's, we can poll and match builds
+ * by their related PR #id.
+ *
+ * That's the case for nodejs.org.
+ */
+function pollByPrThenComment (owner, repoName, prId, checkNumber) {
+  checkNumber = checkNumber || 1
+
+  const prInfo = prInfoStr({ owner, repoName, prId })
+  const createGhComment = createGhCommentFn({ owner, repoName, prId })
+
+  if (checkNumber > 100) {
+    console.warn(`* ${prInfo} Was not able to find matching build for PR, stopping poll now :(`)
+    return
+  }
+
+  travisClient.repos(owner, repoName).builds.get((err, res) => {
+    if (err) {
+      return console.error(`! ${prInfo} Error while retrieving builds`, err.stack)
+    }
+
+    const lastBuildForPr = res.builds.find((build) => build.pull_request_number === prId)
+
+    if (lastBuildForPr) {
+      const lastState = lastBuildForPr.state
+
+      if (lastState === 'passed') {
+        return createGhComment(`[Travis build passed](https://travis-ci.org/${owner}/${repoName}/builds/${lastBuildForPr.id}) :+1:`)
+      } else if (lastState === 'failed') {
+        return createGhComment(`[Travis build failed](https://travis-ci.org/${owner}/${repoName}/builds/${lastBuildForPr.id}) :-1:`)
+      } else if (~['created', 'started'].indexOf(lastState)) {
+        console.log(`* ${prInfo} "${lastState}" build found, will do check #${checkNumber + 1} in 30 seconds`)
+      } else {
+        return console.log(`* ${prInfo} Unknown build state: "${lastState}", stopping polling`)
+      }
+    } else {
+      console.warn(`! ${prInfo} Was not able to find matching build, will do check #${checkNumber + 1} in 30 seconds`)
+    }
+
+    setTimeout(pollByPrThenComment, 30 * 1000, owner, repoName, prId, checkNumber + 1)
+  })
+}
+
+/**
+ * When Travis CI *doesn't* pick up our PR's, we have to poll and match builds
+ * by the last commit SHA of the related PR.
+ *
+ * This is the case for readable-stream.
  */
 function pollByCommitThenStatus (owner, repoName, prId) {
   const prInfo = prInfoStr({ owner, repoName, prId })
@@ -90,6 +157,24 @@ function pollTravisBuildBySha (options, checkNumber) {
   })
 }
 
+function createGhCommentFn (options) {
+  const prInfo = prInfoStr(options)
+
+  return (message) => {
+    githubClient.issues.createComment({
+      user: options.owner,
+      repo: options.repoName,
+      number: options.prId,
+      body: message
+    }, (err, res) => {
+      if (err) {
+        return console.error(`! ${prInfo} Error while creating GitHub comment`, err.stack)
+      }
+      console.log(`* ${prInfo} Github comment created`)
+    })
+  }
+}
+
 function createGhStatusFn (options) {
   const prInfo = prInfoStr(options)