From 6521c869c45d8af4612d996871ba7df803daca89 Mon Sep 17 00:00:00 2001
From: Ivan Zuzak <izuzak@gmail.com>
Date: Mon, 22 Jun 2015 07:56:21 +0200
Subject: [PATCH 1/4] Failing test to demonstrate problem

---
 spec/command-registry-spec.coffee | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/spec/command-registry-spec.coffee b/spec/command-registry-spec.coffee
index b92d3e6b0..799bceb8e 100644
--- a/spec/command-registry-spec.coffee
+++ b/spec/command-registry-spec.coffee
@@ -158,6 +158,15 @@ describe "CommandRegistry", ->
         addError = error
       expect(addError.message).toContain(badSelector)
 
+    it "throws an error when called with an non-function callback", ->
+      badCallback = null
+      addError = null
+      try
+        registry.add '.selector', 'foo:bar', badCallback
+      catch error
+        addError = error
+      expect(addError.message).toContain("Can't register a command with non-function callback.")
+
   describe "::findCommands({target})", ->
     it "returns commands that can be invoked on the target or its ancestors", ->
       registry.add '.parent', 'namespace:command-1', ->

From d47737718be131781c7af48b1414049e7784c705 Mon Sep 17 00:00:00 2001
From: Ivan Zuzak <izuzak@gmail.com>
Date: Mon, 22 Jun 2015 07:59:08 +0200
Subject: [PATCH 2/4] Throw error for commands with non-function callbacks

---
 src/command-registry.coffee | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/command-registry.coffee b/src/command-registry.coffee
index 72098eda0..a9b953536 100644
--- a/src/command-registry.coffee
+++ b/src/command-registry.coffee
@@ -93,6 +93,9 @@ class CommandRegistry
       return disposable
 
     if typeof target is 'string'
+      if typeof callback isnt 'function'
+        throw new Error("Can't register a command with non-function callback.")
+
       validateSelector(target)
       @addSelectorBasedListener(target, commandName, callback)
     else

From 9aa78606b326cfbe0e82acff388230f76b2c5987 Mon Sep 17 00:00:00 2001
From: Ivan Zuzak <izuzak@gmail.com>
Date: Mon, 22 Jun 2015 18:47:41 +0200
Subject: [PATCH 3/4] Catch both string and object targets

---
 src/command-registry.coffee | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/command-registry.coffee b/src/command-registry.coffee
index a9b953536..870093e2f 100644
--- a/src/command-registry.coffee
+++ b/src/command-registry.coffee
@@ -92,10 +92,10 @@ class CommandRegistry
         disposable.add @add(target, commandName, callback)
       return disposable
 
-    if typeof target is 'string'
-      if typeof callback isnt 'function'
-        throw new Error("Can't register a command with non-function callback.")
+    if typeof callback isnt 'function'
+      throw new Error("Can't register a command with non-function callback.")
 
+    if typeof target is 'string'
       validateSelector(target)
       @addSelectorBasedListener(target, commandName, callback)
     else

From 326457d21b6a5f3bf74b6d11761db97e10edda51 Mon Sep 17 00:00:00 2001
From: Ivan Zuzak <izuzak@gmail.com>
Date: Mon, 22 Jun 2015 18:55:08 +0200
Subject: [PATCH 4/4] Add test for object target case

---
 spec/command-registry-spec.coffee | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/spec/command-registry-spec.coffee b/spec/command-registry-spec.coffee
index 799bceb8e..0a8cafa6b 100644
--- a/spec/command-registry-spec.coffee
+++ b/spec/command-registry-spec.coffee
@@ -158,15 +158,26 @@ describe "CommandRegistry", ->
         addError = error
       expect(addError.message).toContain(badSelector)
 
-    it "throws an error when called with an non-function callback", ->
+    it "throws an error when called with a non-function callback and selector target", ->
       badCallback = null
       addError = null
+
       try
         registry.add '.selector', 'foo:bar', badCallback
       catch error
         addError = error
       expect(addError.message).toContain("Can't register a command with non-function callback.")
 
+    it "throws an error when called with an non-function callback and object target", ->
+      badCallback = null
+      addError = null
+
+      try
+        registry.add document.body, 'foo:bar', badCallback
+      catch error
+        addError = error
+      expect(addError.message).toContain("Can't register a command with non-function callback.")
+
   describe "::findCommands({target})", ->
     it "returns commands that can be invoked on the target or its ancestors", ->
       registry.add '.parent', 'namespace:command-1', ->