From 6cf5f81b6c312f90f57d34b6e5c390c5cdebd43a Mon Sep 17 00:00:00 2001
From: Jordan Harband <ljharb@gmail.com>
Date: Mon, 17 Sep 2018 16:16:06 -0700
Subject: [PATCH] [Fix] `utils`: `merge`: fix crash when `source` is a truthy
 primitive & no options are provided

---
 lib/utils.js  | 2 +-
 test/utils.js | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/utils.js b/lib/utils.js
index b2143323..e0ebba2d 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -31,7 +31,7 @@ exports.merge = function (target, source, options) {
         if (Array.isArray(target)) {
             target.push(source);
         } else if (typeof target === 'object') {
-            if (options.plainObjects || options.allowPrototypes || !has.call(Object.prototype, source)) {
+            if ((options && (options.plainObjects || options.allowPrototypes)) || !has.call(Object.prototype, source)) {
                 target[source] = true;
             }
         } else {
diff --git a/test/utils.js b/test/utils.js
index 0721dd8e..999f860d 100644
--- a/test/utils.js
+++ b/test/utils.js
@@ -18,5 +18,8 @@ test('merge()', function (t) {
     var nestedArrays = utils.merge({ foo: ['baz'] }, { foo: ['bar', 'xyzzy'] });
     t.deepEqual(nestedArrays, { foo: ['baz', 'bar', 'xyzzy'] });
 
+    var noOptionsNonObjectSource = utils.merge({ foo: 'baz' }, 'bar');
+    t.deepEqual(noOptionsNonObjectSource, { foo: 'baz', bar: true });
+
     t.end();
 });