diff --git a/lib/ace/commands/command_manager.js b/lib/ace/commands/command_manager.js
index 80626578..f497129d 100644
--- a/lib/ace/commands/command_manager.js
+++ b/lib/ace/commands/command_manager.js
@@ -100,7 +100,7 @@ var CommandManager = function(platform, commands) {
         if (!command)
             return false;
 
-        if (editor.$readOnly && !command.readOnly)
+        if (editor && editor.$readOnly && !command.readOnly)
             return false;
 
         command.exec(editor, args || {});
diff --git a/lib/ace/test/all_browser.js b/lib/ace/test/all_browser.js
index 3aa49594..6af75012 100644
--- a/lib/ace/test/all_browser.js
+++ b/lib/ace/test/all_browser.js
@@ -11,6 +11,7 @@ var log = document.getElementById("log")
 
 var tests = [
      require("ace/anchor_test"),
+     require("ace/commands/command_manager_test"),
      require("ace/document_test"),
      require("ace/edit_session_test"),
      require("ace/editor_change_document_test"),