Extract EventEmitter mixin

src/atom/buffer.coffee

@@ -1,6 +1,7 @@
 _ = require 'underscore'
 fs = require 'fs'
 Range = require 'range'
+EventEmitter = require 'event-emitter'
 
 module.exports =
 class Buffer
@@ -90,14 +91,6 @@ class Buffer
     if not @path then throw new Error("Tried to save buffer with no url")
     fs.write @path, @getText()
 
-  on: (eventName, handler) ->
-    @eventHandlers ?= {}
-    @eventHandlers[eventName] ?= []
-    @eventHandlers[eventName].push(handler)
-
-  trigger: (eventName, event) ->
-    @eventHandlers?[eventName]?.forEach (handler) -> handler(event)
-
   modeName: ->
     extension = if @path then @path.split('/').pop().split('.').pop() else null
     switch extension
@@ -109,3 +102,4 @@ class Buffer
       when 'css' then 'css'
       else 'text'
 
+_.extend(Buffer.prototype, EventEmitter)

src/atom/event-emitter.coffee

@@ -0,0 +1,8 @@
+module.exports =
+  on: (eventName, handler) ->
+    @eventHandlers ?= {}
+    @eventHandlers[eventName] ?= []
+    @eventHandlers[eventName].push(handler)
+
+  trigger: (eventName, event) ->
+    @eventHandlers?[eventName]?.forEach (handler) -> handler(event)

src/atom/highlighter.coffee

@@ -1,4 +1,5 @@
 _ = require 'underscore'
+EventEmitter = require 'event-emitter'
 
 module.exports =
 class Highlighter
@@ -59,10 +60,4 @@ class Highlighter
   tokensForRow: (row) ->
     @lines[row].tokens
 
-  on: (eventName, handler) ->
-    @eventHandlers ?= {}
-    @eventHandlers[eventName] ?= []
-    @eventHandlers[eventName].push(handler)
-
-  trigger: (eventName, event) ->
-    @eventHandlers?[eventName]?.forEach (handler) -> handler(event)
+_.extend(Highlighter.prototype, EventEmitter)

src/atom/line-wrapper.coffee

@@ -1,4 +1,7 @@
+_ = require 'underscore'
 Point = require 'point'
+EventEmitter = require 'event-emitter'
+
 getWordRegex = -> /\b[^\s]+/g
 
 module.exports =
@@ -6,6 +9,8 @@ class LineWrapper
   constructor: (@maxLength, @highlighter) ->
     @buffer = @highlighter.buffer
     @buildWrappedLines()
+    @highlighter.on 'change', (e) =>
+      @wrappedLines[e.oldRange.start.row] = @buildWrappedLineForBufferRow(e.newRange.start.row)
 
   setMaxLength: (@maxLength) ->
     @buildWrappedLines()
@@ -83,3 +88,5 @@ class LineWrapper
       for screenLine in wrappedLine.screenLines
         return screenLine if currentScreenRow == screenRow
         currentScreenRow++
+
+_.extend(LineWrapper.prototype, EventEmitter)