From 0588e148501ea47b113e00a0bafc4a4bc00460e6 Mon Sep 17 00:00:00 2001
From: Ben Ogle <ogle.ben@gmail.com>
Date: Mon, 13 Oct 2014 14:25:55 -0700
Subject: [PATCH] Only notify when changed key path is really sub path of
 observed path

Closes #3775
---
 spec/config-spec.coffee |  8 ++++++++
 src/config.coffee       | 14 ++++++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/spec/config-spec.coffee b/spec/config-spec.coffee
index 8f6dad245..fcd2e44c3 100644
--- a/spec/config-spec.coffee
+++ b/spec/config-spec.coffee
@@ -340,6 +340,14 @@ describe "Config", ->
       atom.config.set('foo.bar.baz', "value 2")
       expect(observeHandler).not.toHaveBeenCalled()
 
+    it 'does not fire the callback for a similarly named keyPath', ->
+      bazCatHandler = jasmine.createSpy("bazCatHandler")
+      observeSubscription = atom.config.observe "foo.bar.bazCat", bazCatHandler
+
+      bazCatHandler.reset()
+      atom.config.set('foo.bar.baz', "value 10")
+      expect(bazCatHandler).not.toHaveBeenCalled()
+
   describe ".initializeConfigDirectory()", ->
     beforeEach ->
       if fs.existsSync(dotAtomPath)
diff --git a/src/config.coffee b/src/config.coffee
index cd2476fbe..53c966d90 100644
--- a/src/config.coffee
+++ b/src/config.coffee
@@ -747,12 +747,18 @@ class Config
 
   observeKeyPath: (keyPath, options, callback) ->
     callback(_.clone(@get(keyPath))) unless options.callNow == false
-    @emitter.on 'did-change', (event) ->
-      callback(event.newValue) if keyPath? and keyPath.indexOf(event?.keyPath) is 0
+    @emitter.on 'did-change', (event) =>
+      callback(event.newValue) if keyPath? and @isSubKeyPath(keyPath, event?.keyPath)
 
   onDidChangeKeyPath: (keyPath, callback) ->
-    @emitter.on 'did-change', (event) ->
-      callback(event) if not keyPath? or (keyPath? and keyPath.indexOf(event?.keyPath) is 0)
+    @emitter.on 'did-change', (event) =>
+      callback(event) if not keyPath? or (keyPath? and @isSubKeyPath(keyPath, event?.keyPath))
+
+  isSubKeyPath: (keyPath, subKeyPath) ->
+    return false unless keyPath? and subKeyPath?
+    pathSubTokens = subKeyPath.split('.')
+    pathTokens = keyPath.split('.').slice(0, pathSubTokens.length)
+    _.isEqual(pathTokens, pathSubTokens)
 
   setRawDefault: (keyPath, value) ->
     oldValue = _.clone(@get(keyPath))