From 6b4ce902baebaafd8a397f1a99ebcd7fb00bc42c Mon Sep 17 00:00:00 2001
From: Ben Ogle <ogle.ben@gmail.com>
Date: Thu, 25 Sep 2014 12:37:02 -0700
Subject: [PATCH] Undefined in Config::set always unsets the value

---
 spec/config-spec.coffee | 17 +++++++++++++++++
 src/config.coffee       |  9 +++++----
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/spec/config-spec.coffee b/spec/config-spec.coffee
index 4e7aad526..4c006a24e 100644
--- a/spec/config-spec.coffee
+++ b/spec/config-spec.coffee
@@ -577,6 +577,23 @@ describe "Config", ->
         atom.config.set('foo.bar.anInt', 'cats')
         expect(atom.config.get('foo.bar.anInt')).toBe 'cats'
 
+    describe 'when the value has an "string" and "boolean" type', ->
+      beforeEach ->
+        schema =
+          type: ['string', 'boolean']
+          default: 'def'
+        atom.config.setSchema('foo.bar', schema)
+
+      it 'can set a string, a boolean, and unset', ->
+        atom.config.set('foo.bar', 'ok')
+        expect(atom.config.get('foo.bar')).toBe 'ok'
+
+        atom.config.set('foo.bar', false)
+        expect(atom.config.get('foo.bar')).toBe false
+
+        atom.config.set('foo.bar', undefined)
+        expect(atom.config.get('foo.bar')).toBe 'def'
+
     describe 'when the value has a "number" type', ->
       beforeEach ->
         schema =
diff --git a/src/config.coffee b/src/config.coffee
index d5fe28dd5..930d2d419 100644
--- a/src/config.coffee
+++ b/src/config.coffee
@@ -381,10 +381,11 @@ class Config
   # * `true` if the value was set.
   # * `false` if the value was not able to be coerced to the type specified in the setting's schema.
   set: (keyPath, value) ->
-    try
-      value = @scrubValue(keyPath, value)
-    catch e
-      return false
+    unless value == undefined
+      try
+        value = @scrubValue(keyPath, value)
+      catch e
+        return false
 
     if @get(keyPath) isnt value
       defaultValue = _.valueForKeyPath(@defaultSettings, keyPath)