diff --git a/packages/babel-plugin-transform-es2015-parameters/test/fixtures/parameters/rest-member-expression-optimisation/expected.js b/packages/babel-plugin-transform-es2015-parameters/test/fixtures/parameters/rest-member-expression-optimisation/expected.js
index 7830720e3e..62aab77ce7 100644
--- a/packages/babel-plugin-transform-es2015-parameters/test/fixtures/parameters/rest-member-expression-optimisation/expected.js
+++ b/packages/babel-plugin-transform-es2015-parameters/test/fixtures/parameters/rest-member-expression-optimisation/expected.js
@@ -20,11 +20,7 @@ function t() {
 
 
 function t() {
-  for (var _len = arguments.length, items = Array(_len), _key = 0; _key < _len; _key++) {
-    items[_key] = arguments[_key];
-  }
-
-  for (var i = 0; i < items.length; i++) {
-    return items[i];
+  for (var i = 0; i < arguments.length; i++) {
+    return arguments.length <= i ? undefined : arguments[i];
   }
 }
diff --git a/packages/babel-traverse/src/path/introspection.js b/packages/babel-traverse/src/path/introspection.js
index 1888a6e2af..a72eca0078 100644
--- a/packages/babel-traverse/src/path/introspection.js
+++ b/packages/babel-traverse/src/path/introspection.js
@@ -270,12 +270,9 @@ export function _guessExecutionStatusRelativeTo(target) {
   }
 
   // otherwise we're associated by a parent node, check which key comes before the other
-  const targetKeyPosition = t.VISITOR_KEYS[targetRelationship.type].indexOf(
-    targetRelationship.key,
-  );
-  const selfKeyPosition = t.VISITOR_KEYS[selfRelationship.type].indexOf(
-    selfRelationship.key,
-  );
+  const keys = t.VISITOR_KEYS[commonPath.type];
+  const targetKeyPosition = keys.indexOf(targetRelationship.key);
+  const selfKeyPosition = keys.indexOf(selfRelationship.key);
   return targetKeyPosition > selfKeyPosition ? "before" : "after";
 }