added check to queue.push(). Fixes #593

3 files changed, 15 insertions, 2 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index eabdf28..f6960bc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,7 @@ Bug Fixes:
 - Ensure proper conditions when calling `drain()` after pushing an empty data set to a queue (#668)
 - `each` and family will properly handle an empty array (#578)
 - `eachSeries` and family will finish if the underlying array is modified during execution (#557)
+- `queue` will throw if a non-function is passed to `q.push()` (#593)
 - Doc fixes (#766)
 
 
diff --git a/lib/async.js b/lib/async.js
index ba90413..fd7a953 100644
--- a/lib/async.js
+++ b/lib/async.js
@@ -807,6 +807,9 @@
             throw new Error('Concurrency must not be zero');
         }
         function _insert(q, data, pos, callback) {
+            if (callback != null && typeof callback !== "function") {
+                throw new Error("task callback must be a function");
+            }
             q.started = true;
             if (!_isArray(data)) {
                 data = [data];
@@ -940,9 +943,10 @@
         }
 
         function _insert(q, data, priority, callback) {
-            if (!q.started){
-                q.started = true;
+            if (callback != null && typeof callback !== "function") {
+                throw new Error("task callback must be a function");
             }
+            q.started = true;
             if (!_isArray(data)) {
                 data = [data];
             }
diff --git a/test/test-async.js b/test/test-async.js
index 2f51443..bdb8147 100755
--- a/test/test-async.js
+++ b/test/test-async.js
@@ -2848,6 +2848,14 @@ exports['queue'] = {
     }, 800);
 },
 
+'push with non-function': function (test) {
+    var q = async.queue(function () {}, 1);
+    test.throws(function () {
+        q.push({}, 1);
+    });
+    test.done();
+},
+
 'unshift': function (test) {
     var queue_order = [];