ES6-ify codebase (#1553)

* cancelable foreach

* cancelable waterfall

* cancellable auto

* fix lint

* fix tests

* cancelable whilst/until/during/forever

* fix waterfall test.  It WILL get there

* docs

* use rest params instead of slice

* clean up internals

* remove property func

* clarify uses of createTester

* happy path async funtions in asyncify

* stop using arguments

* DLL to class

* moar arrows

* fix merge issues

* remove forOwn

* moar arrows

* fix merge mistake

* even more arrows, what can stop him

* mo more fn.apply(null,...)

* remove more spurious uses of apply

* update lint config

* just when you thought there couldn't possibly be more arrows

* use eslint:recommended

* even less uses or aguments

* get rid of prototype cuteness

* fix concat tests

* fix more tests

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/internal/map.js b/lib/internal/map.js
index c7f64dd..b99d8ee 100644
--- a/lib/internal/map.js
+++ b/lib/internal/map.js
@@ -8,13 +8,13 @@ export default function _asyncMap(eachfn, arr, iteratee, callback) {
     var counter = 0;
     var _iteratee = wrapAsync(iteratee);
 
-    eachfn(arr, function (value, _, callback) {
+    return eachfn(arr, (value, _, callback) => {
         var index = counter++;
-        _iteratee(value, function (err, v) {
+        _iteratee(value, (err, v) => {
             results[index] = v;
             callback(err);
         });
-    }, function (err) {
+    }, err => {
         callback(err, results);
     });
 }