suppress mutation of input `options` (#3785)

1 files changed, 4 insertions, 8 deletions

diff --git a/lib/utils.js b/lib/utils.js
index 508aba9c..7932e05f 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -87,15 +87,11 @@ DefaultsError.prototype.name = "DefaultsError";
 configure_error_stack(DefaultsError);
 
 function defaults(args, defs, croak) {
-    if (args === true) args = {};
-    var ret = args || {};
-    if (croak) for (var i in ret) if (HOP(ret, i) && !HOP(defs, i)) {
-        throw new DefaultsError("`" + i + "` is not a supported option", defs);
+    for (var i in args) if (HOP(args, i)) {
+        if (croak && !HOP(defs, i)) throw new DefaultsError("`" + i + "` is not a supported option", defs);
+        defs[i] = args[i];
     }
-    for (var i in defs) if (HOP(defs, i)) {
-        ret[i] = (args && HOP(args, i)) ? args[i] : defs[i];
-    }
-    return ret;
+    return defs;
 }
 
 function merge(obj, ext) {