From fbaf956e1fda3ae610ac01c50ebb39df0a2b3676 Mon Sep 17 00:00:00 2001
From: Nathan Sobo <nathan@github.com>
Date: Fri, 5 Sep 2014 09:10:22 -0600
Subject: [PATCH] Handle .stopPropagation() being called on command events

---
 spec/command-registry-spec.coffee | 10 ++++++++++
 src/command-registry.coffee       |  6 +++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/spec/command-registry-spec.coffee b/spec/command-registry-spec.coffee
index 28071932a..a76767523 100644
--- a/spec/command-registry-spec.coffee
+++ b/spec/command-registry-spec.coffee
@@ -57,3 +57,13 @@ describe "CommandRegistry", ->
 
     grandchild.dispatchEvent(new CustomEvent('command', bubbles: true))
     expect(calls).toEqual ['.foo.bar', '.bar', '.foo']
+
+  it "stops bubbling through ancestors when .stopPropagation() is called on the event", ->
+    calls = []
+
+    registry.add 'command', '.parent', -> calls.push('parent')
+    registry.add 'command', '.child', -> calls.push('child-2')
+    registry.add 'command', '.child', (event) -> calls.push('child-1'); event.stopPropagation()
+
+    grandchild.dispatchEvent(new CustomEvent('command', bubbles: true))
+    expect(calls).toEqual ['child-1', 'child-2']
diff --git a/src/command-registry.coffee b/src/command-registry.coffee
index 69776319d..cb29c4a2f 100644
--- a/src/command-registry.coffee
+++ b/src/command-registry.coffee
@@ -16,11 +16,14 @@ class CommandRegistry
     @listenersByCommandName[commandName].push(new CommandListener(selector, callback))
 
   dispatchCommand: (event) =>
+    propagationStopped = false
+    currentTarget = event.target
+
     syntheticEvent = Object.create event,
       eventPhase: value: Event.BUBBLING_PHASE
       currentTarget: get: -> currentTarget
+      stopPropagation: value: -> propagationStopped = true
 
-    currentTarget = event.target
     loop
       matchingListeners =
         @listenersByCommandName[event.type]
@@ -30,6 +33,7 @@ class CommandRegistry
       for listener in matchingListeners
         listener.callback.call(currentTarget, syntheticEvent)
 
+      break if propagationStopped
       break if currentTarget is @rootNode
       currentTarget = currentTarget.parentNode