增加 ActiveModel 的测试，README 增加相关说明; #3

Gemfile

@@ -1,3 +1,5 @@
 source 'https://rubygems.org'
 gemspec
-gem 'rspec'
+gem 'rspec'
+gem 'activesupport'
+gem 'activemodel'

Gemfile.lock

@@ -7,12 +7,16 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
+    activemodel (4.1.4)
+      activesupport (= 4.1.4)
+      builder (~> 3.1)
     activesupport (4.1.4)
       i18n (~> 0.6, >= 0.6.9)
       json (~> 1.7, >= 1.7.7)
       minitest (~> 5.1)
       thread_safe (~> 0.1)
       tzinfo (~> 1.1)
+    builder (3.2.2)
     diff-lcs (1.2.4)
     i18n (0.6.11)
     json (1.8.1)
@@ -33,5 +37,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  activemodel
+  activesupport
   auto-correct!
   rspec

README.md

@@ -36,6 +36,34 @@ irb> "bootstrap control-group对齐问题".auto_correct!
 Bootstrap control-group 对齐问
 ```
 
+## ActiveModel 的 changed? 相关提示
+
+由于 auto_correct 是直接修改原始变量值的，你可能会遇到由于没有引发 `ActiveModel::Dirty` 的相关 callback 事件而导致下面这种场景 ActiveModel 不会将相关的字段写入到数据库。
+
+比如下面的情况：
+
+```ruby
+class Topic < ActiveRecord::Base
+  before_save do
+    self.title.auto_correct!
+  end
+end
+```
+
+正确的方式：
+
+```ruby
+class Topic < ActiveRecord::Base
+  before_save do
+    # 引发 ActiveModel::Dirty 的 change
+    self.title_will_change!
+    self.title.auto_correct!
+  end
+end
+```
+
+具体请参见 [ActiveModel::Dirty 的文档](http://api.rubyonrails.org/classes/ActiveModel/Dirty.html)
+
 ## 性能
 
 详见 Rakefile

spec/text_spec.rb

@@ -1,5 +1,14 @@
 # coding: utf-8
 require "auto-correct"
+require "active_support/all"
+require "active_model"
+
+class User
+  include ActiveModel::Dirty
+  attr_accessor :name
+
+  define_attribute_methods :name
+end
 
 describe "AutoCorrect" do
   let(:text) { "" }
@@ -171,5 +180,17 @@
       it { "全新的ruby web框架：lotus".auto_correct!.should == "全新的 Ruby web 框架：Lotus" }
       it { "grape写纯 api，选择哪个oauth gem好呢？".auto_correct!.should == "Grape 写纯 API，选择哪个 OAuth gem 好呢？" }
     end
+
+    context 'with ActiveModel field_changed?' do
+      it {
+        u = User.new
+        u.name = "foo的"
+        u.name_changed?.should == false
+        u.name_will_change!
+        u.name.auto_correct!.should == "foo 的"
+        u.name_change.should == ["foo的","foo 的"]
+        u.name_changed?.should == true
+      }
+    end
   end
 end