From 64dd9a2448b999887e17171ceafaade0ddd4af85 Mon Sep 17 00:00:00 2001
From: Antonio Scandurra <as-cii@github.com>
Date: Fri, 20 Oct 2017 14:13:03 +0200
Subject: [PATCH] Don't watch editors more than once if they're re-added to the
 workspace

---
 lib/whitespace.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/whitespace.js b/lib/whitespace.js
index 92defde..c3ec304 100644
--- a/lib/whitespace.js
+++ b/lib/whitespace.js
@@ -4,6 +4,7 @@ const TRAILING_WHITESPACE_REGEX = /[ \t]+(?=\r?$)/g
 
 module.exports = class Whitespace {
   constructor () {
+    this.watchedEditors = new WeakSet()
     this.subscriptions = new CompositeDisposable()
 
     this.subscriptions.add(atom.workspace.observeTextEditors(editor => {
@@ -69,6 +70,8 @@ module.exports = class Whitespace {
   }
 
   handleEvents (editor) {
+    if (this.watchedEditors.has(editor)) return
+
     let buffer = editor.getBuffer()
 
     let bufferSavedSubscription = buffer.onWillSave(() => {
@@ -116,11 +119,13 @@ module.exports = class Whitespace {
       this.subscriptions.remove(bufferSavedSubscription)
       this.subscriptions.remove(editorTextInsertedSubscription)
       this.subscriptions.remove(editorDestroyedSubscription)
+      this.watchedEditors.delete(editor)
     })
 
     this.subscriptions.add(bufferSavedSubscription)
     this.subscriptions.add(editorTextInsertedSubscription)
     this.subscriptions.add(editorDestroyedSubscription)
+    this.watchedEditors.add(editor)
   }
 
   removeTrailingWhitespace (editor, grammarScopeName) {