Strings accept numbers too

spec/config-spec.coffee

@@ -671,12 +671,21 @@ describe "Config", ->
         atom.config.set('foo.bar.aString', 'yep')
         expect(atom.config.get('foo.bar.aString')).toBe 'yep'
 
-      it 'will not set non-strings', ->
-        expect(atom.config.set('foo.bar.aString', null)).toBe false
-        expect(atom.config.get('foo.bar.aString')).toBe 'ok'
+      it 'will only set strings, numbers and booleans', ->
+        expect(atom.config.set('foo.bar.aString', 123)).toBe true
+        expect(atom.config.get('foo.bar.aString')).toBe '123'
 
-        expect(atom.config.set('foo.bar.aString', 123)).toBe false
-        expect(atom.config.get('foo.bar.aString')).toBe 'ok'
+        expect(atom.config.set('foo.bar.aString', true)).toBe false
+        expect(atom.config.get('foo.bar.aString')).toBe '123'
+
+        expect(atom.config.set('foo.bar.aString', null)).toBe false
+        expect(atom.config.get('foo.bar.aString')).toBe '123'
+
+        expect(atom.config.set('foo.bar.aString', [])).toBe false
+        expect(atom.config.get('foo.bar.aString')).toBe '123'
+
+        expect(atom.config.set('foo.bar.aString', nope: 'nope')).toBe false
+        expect(atom.config.get('foo.bar.aString')).toBe '123'
 
     describe 'when the value has an "object" type', ->
       beforeEach ->

src/config.coffee

@@ -390,7 +390,8 @@ class Config
   # This value is stored in Atom's internal configuration file.
   #
   # * `keyPath` The {String} name of the key.
-  # * `value` The value of the setting.
+  # * `value` The value of the setting. Passing `undefined` will revert the
+  #   setting to the default value.
   #
   # Returns a {Boolean}
   # * `true` if the value was set.
@@ -672,8 +673,11 @@ Config.addSchemaValidators
 
   'string':
     coercion: (keyPath, value, schema) ->
-      throw new Error("Validation failed at #{keyPath}, #{JSON.stringify(value)} must be a string") if typeof value isnt 'string'
-      value
+      switch typeof value
+        when 'number', 'string'
+          value.toString()
+        else
+          throw new Error("Validation failed at #{keyPath}, #{JSON.stringify(value)} must be a string or number")
 
   'null':
     # null sort of isnt supported. It will just unset in this case