Stricter type checking

1 files changed, 10 insertions, 4 deletions

diff --git a/lib/async.js b/lib/async.js
index f3cfb80..d5dfce5 100644
--- a/lib/async.js
+++ b/lib/async.js
@@ -62,6 +62,12 @@
         return _toString.call(obj) === '[object Array]';
     };
 
+    // Ported from underscore.js isObject
+    var _isObject = function(obj) {
+        var type = typeof obj;
+        return type === 'function' || type === 'object' && !!obj;
+    };
+
     function _isArrayLike(arr) {
         return _isArray(arr) || (
             // has a positive integer length property
@@ -1013,7 +1019,7 @@
     function _console_fn(name) {
         return _restParam(function (fn, args) {
             fn.apply(null, args.concat([_restParam(function (err, args) {
-                if (typeof console !== 'undefined') {
+                if (typeof console === 'object') {
                     if (err) {
                         if (console.error) {
                             console.error(err);
@@ -1186,7 +1192,7 @@
                 return callback(e);
             }
             // if result is Promise object
-            if (typeof result !== 'undefined' && typeof result.then === "function") {
+            if (_isObject(result) && typeof result.then === "function") {
                 result.then(function(value) {
                     callback(null, value);
                 }).catch(function(err) {
@@ -1199,11 +1205,11 @@
     };
 
     // Node.js
-    if (typeof module !== 'undefined' && module.exports) {
+    if (typeof module === 'object' && module.exports) {
         module.exports = async;
     }
     // AMD / RequireJS
-    else if (typeof define !== 'undefined' && define.amd) {
+    else if (typeof define === 'function' && define.amd) {
         define([], function () {
             return async;
         });