PR fixesconcat-order

2 files changed, 20 insertions, 9 deletions

diff --git a/lib/concatLimit.js b/lib/concatLimit.js
index 8b8f5d8..4df03ea 100644
--- a/lib/concatLimit.js
+++ b/lib/concatLimit.js
@@ -3,6 +3,8 @@ import wrapAsync from './internal/wrapAsync';
 import slice from './internal/slice';
 import mapLimit from './mapLimit';
 
+var _concat = Array.prototype.concat;
+
 /**
  * The same as [`concat`]{@link module:Collections.concat} but runs a maximum of `limit` async operations at a time.
  *
@@ -31,7 +33,6 @@ export default function(coll, limit, iteratee, callback) {
         });
     }, function(err, mapResults) {
         var result = [];
-        var _concat = Array.prototype.concat;
         for (var i = 0; i < mapResults.length; i++) {
             if (mapResults[i]) {
                 result = _concat.apply(result, mapResults[i]);
diff --git a/mocha_test/concat.js b/mocha_test/concat.js
index f84a84b..f6b73b3 100644
--- a/mocha_test/concat.js
+++ b/mocha_test/concat.js
@@ -307,9 +307,9 @@ describe('concat', function() {
         it('does not continue replenishing after error', function(done) {
             var started = 0;
             var arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
-            var delay = 10;
             var limit = 3;
-            var maxTime = 10 * arr.length;
+            var step = 0;
+            var maxSteps = arr.length;
 
             async.concatLimit(arr, limit, function(val, next) {
                 started++;
@@ -317,18 +317,28 @@ describe('concat', function() {
                     return next(new Error('fail'));
                 }
 
-                setTimeout(function() {
+                async.setImmediate(function() {
                     next();
-                }, delay);
+                });
             }, function(err, result) {
                 expect(err).to.not.eql(null);
                 expect(result).to.be.an('array').that.is.empty;
             });
 
-            setTimeout(function() {
-                expect(started).to.equal(3);
-                done();
-            }, maxTime);
+            // wait `maxSteps` event loop cycles before calling done to ensure
+            // the iteratee is not called on more items in arr.
+            function waitCycle() {
+                step++;
+                if (step >= maxSteps) {
+                    expect(started).to.equal(3);
+                    done();
+                    return;
+                } else {
+                    async.setImmediate(waitCycle);
+                }
+            }
+
+            async.setImmediate(waitCycle);
         });
     });