From 364eafe511cdc4f162d48bb4594be9b9b45cd315 Mon Sep 17 00:00:00 2001
From: Brian Cavalier <brian@hovercraftstudios.com>
Date: Fri, 9 Mar 2012 14:28:35 -0500
Subject: [PATCH] Fix #23 - incorrect check for callback allowed passing null
 as a callback to clobber the resolution value.

---
 test/cancelable.js | 16 ++++++++++++++++
 when.js            |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/test/cancelable.js b/test/cancelable.js
index 9afe9cfc..142cdbe2 100644
--- a/test/cancelable.js
+++ b/test/cancelable.js
@@ -38,6 +38,22 @@ buster.testCase('when/cancelable', {
 				done();
 			}
 		);
+	},
+
+	'should propagate the unaltered resolution value': function(done) {
+		var c = cancelable(when.defer(), function() { return false; });
+		c.resolve(true);
+
+		c.then(
+			function(val) {
+				assert(val);
+				done();
+			},
+			function() {
+				buster.fail();
+				done();
+			}
+		);
 
 	}
 });
diff --git a/when.js b/when.js
index 37b5b78f..d2141224 100644
--- a/when.js
+++ b/when.js
@@ -110,7 +110,7 @@ define(function() {
 
             var nextValue;
             try {
-                nextValue = callback && callback(value);
+				if(callback) nextValue = callback(value);
                 return promise(nextValue === undef ? value : nextValue);
             } catch(e) {
                 return rejected(e);