From 2cae6e4b01cf983f0b8da8c4e24af80362459a0c Mon Sep 17 00:00:00 2001
From: Sean Micklethwaite <sean@sdmworld.co.uk>
Date: Tue, 30 May 2017 14:31:12 +0100
Subject: [PATCH] Fix #91

---
 lib/instrumenters/istanbul.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/instrumenters/istanbul.js b/lib/instrumenters/istanbul.js
index c1d4b1338..38e5315bc 100644
--- a/lib/instrumenters/istanbul.js
+++ b/lib/instrumenters/istanbul.js
@@ -11,7 +11,8 @@ function InstrumenterIstanbul (cwd, options) {
     embedSource: true,
     noCompact: false,
     preserveComments: true,
-    produceSourceMap: options.produceSourceMap
+    produceSourceMap: options.produceSourceMap,
+    esModules: true
   })
 
   return {