Fix recursive callback args (#32)

.gitignore

@@ -1,2 +1,3 @@
 components
 build
+node_modules

index.js

@@ -24,8 +24,9 @@ function debounce(func, wait, immediate){
     } else {
       timeout = null;
       if (!immediate) {
-        result = func.apply(context, args);
+        var callContext = context, callArgs = args
         context = args = null;
+        result = func.apply(callContext, callArgs);
       }
     }
   };
@@ -37,8 +38,9 @@ function debounce(func, wait, immediate){
     var callNow = immediate && !timeout;
     if (!timeout) timeout = setTimeout(later, wait);
     if (callNow) {
-      result = func.apply(context, args);
+      var callContext = context, callArgs = args
       context = args = null;
+      result = func.apply(callContext, callArgs);
     }
 
     return result;

test.js

@@ -167,4 +167,24 @@ describe('forcing execution', function() {
 
   })
 
+  it('should execute with correct args when called again from within timeout', function() {
+    const callback = sinon.spy(n =>
+      // recursively call debounced function until n == 0
+      --n && fn(n)
+    );
+
+    const fn = debounce(callback, 100)
+
+    fn(3)
+
+    clock.tick(125)
+    clock.tick(250)
+    clock.tick(375)
+
+    expect(callback.callCount).toEqual(3)
+    expect(callback.args[0]).toEqual([3])
+    expect(callback.args[1]).toEqual([2])
+    expect(callback.args[2]).toEqual([1])
+  });
+
 })