Use closure wrapper with current event name

spec/extensions/editor-command-spec.coffee

@@ -114,12 +114,14 @@ describe "EditorCommand", ->
 
     it "registers all keymaps", ->
       callbackCount = 0
+      eventName = null
       class CustomCommand extends EditorCommand
         @getKeymaps: (editor) ->
           'meta-V': 'custom1'
           'meta-B': 'custom2'
 
         @execute: (editor, event) ->
+          eventName = event
           @replaceSelectedText editor, (text) ->
             callbackCount++
             text
@@ -129,7 +131,9 @@ describe "EditorCommand", ->
         editor.selectToEndOfLine()
         editor.trigger 'custom1'
         expect(callbackCount).toBe 1
+        expect(eventName).toBe 'custom1'
         editor.trigger 'custom2'
+        expect(eventName).toBe 'custom2'
         expect(callbackCount).toBe 2
 
   describe "LowerCaseCommand", ->

src/extensions/editor-command.coffee

@@ -18,7 +18,9 @@ class EditorCommand
     return unless keymaps
 
     for key, event of keymaps
-      editor.on event, => @execute(editor, event)
+      do (event) =>
+        editor.on event, =>
+          @execute(editor, event)
 
   @replaceSelectedText: (editor, replace) ->
      selection = editor.getSelection()