From 8a760e0a93aa2bc7a45002ac15a5b951d054d44c Mon Sep 17 00:00:00 2001
From: Tom Clarkson <tom@orangeguava.com>
Date: Mon, 3 Apr 2017 11:08:16 -0700
Subject: [PATCH] Code analysis bot does not need to comment on merge commits

Summary:
This PR fixes a CI issue that came up on #11304 after merging master into the pr branch.

That created a merge commit with over 1000 changed files. That might have created irrelevant comments, but the github commit api is limited to 300 files, with only the first 294 having the expected diffs included.

I can't think of any reasonable scenario where a merge would have changes that aren't either on master or another commit in the PR, so I've updated it to treat merge commits as having no changes.
Closes https://github.com/facebook/react-native/pull/13260

Differential Revision: D4819805

Pulled By: ericvicenti

fbshipit-source-id: 7b6b51b18bb36503a719a3ba5c9163cd6ef00e17
---
 bots/code-analysis-bot.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/bots/code-analysis-bot.js b/bots/code-analysis-bot.js
index d22ffb29a..0c3a8bdda 100644
--- a/bots/code-analysis-bot.js
+++ b/bots/code-analysis-bot.js
@@ -111,6 +111,11 @@ function getFilesFromCommit(user, repo, sha, callback) {
       console.log(error);
       return;
     }
+    // A merge commit should not have any new changes to report
+    if (res.parents && res.parents.length > 1) {
+      return;
+    }
+
     callback(res.files);
   });
 }
@@ -181,6 +186,10 @@ function main(messages, user, repo, number) {
       files
         .filter((file) => messages[file.filename])
         .forEach((file) => {
+          // github api sometimes does not return a patch on large commits
+          if (!file.patch) {
+            return;
+          }
           var lineMap = getLineMapFromPatch(file.patch);
           messages[file.filename].forEach((message) => {
             sendComment(user, repo, number, sha, file.filename, lineMap, message);