From dfa7e3747626c09d03c080394ba2dfb3169874cc Mon Sep 17 00:00:00 2001
From: Jason Wray <jason@mapbox.com>
Date: Tue, 7 Aug 2018 15:06:55 -0400
Subject: [PATCH] [build] Fix CI failure when master and release branch are
 identical

The search for branches containing the previous hash could return multiple matches on different lines, if, for instance, a newly-cut release branch were identical to master.
---
 scripts/environment.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/environment.js b/scripts/environment.js
index 9777377f1..bb0be7788 100755
--- a/scripts/environment.js
+++ b/scripts/environment.js
@@ -24,7 +24,7 @@ if (pr) {
 } else {
     const head = process.env['CIRCLE_SHA1'];
     for (const sha of execSync(`git rev-list --max-count=10 ${head}`).toString().trim().split('\n')) {
-        const base = execSync(`git branch -r --contains ${sha} origin/master origin/release-*`).toString().trim().replace(/^origin\//, '');
+        const base = execSync(`git branch -r --contains ${sha} origin/master origin/release-*`).toString().replace(/$\n.*/m, '').trim().replace(/^origin\//, '');
         if (base) {
             const mergeBase = execSync(`git merge-base origin/${base} ${head}`).toString().trim();
             console.log(`export CIRCLE_TARGET_BRANCH=${base}`);