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 1 require File.dirname(FILE) + ‘/../test_helper’

 2 

 3 class TransactionStateOrderingTest < Test::Unit::TestCase

 4   TransactionState::StatusNames.each do |status|

 5     define_method("test_#{status}query_method") do

 6       assert TransactionState.send(status).send("#{status}?"), status

 7       (TransactionState::StatusNames – [status]).each do |inner_status|

 8         assert !TransactionState.send(status).send("#{inner_status}?"), innerstatus

 9       end

10     end

11   end

12 end

 1 class TransactionState

 2   StatusNames = %w(started approved processed completed cancelled).freeze

 3 

 4   attr_reader :name, :index

 5   alias_method :to_s, :name

 6 

 7   def initialize(name)

 8     name</span>, <span class="iv">index = name.to_s, StatusNames.index(name.to_s)

 9     raise "Unknown status name: #{name.inspect}" unless index</span>
<span class="no"><strong>10</strong></span>   <span class="r">end</span>
<span class="no">11</span> 
<span class="no">12</span>   <span class="c"># Generate instance methods to query the state of this instance.</span>
<span class="no">13</span>   <span class="c"># Generates #started? and #completed?, among others.</span>
<span class="no">14</span>   <span class="co">StatusNames</span>.each <span class="r">do</span> |status|
<span class="no"><strong>15</strong></span>     define_method(<span class="s"><span class="dl">&quot;</span><span class="il"><span class="idl">#{</span>status<span class="idl">}</span></span><span class="k">?</span><span class="dl">&quot;</span></span>) <span class="r">do</span>
<span class="no">16</span>       <span class="pc">self</span>.name == <span class="co">TransactionState</span>.send(status).name
<span class="no">17</span>     <span class="r">end</span>
<span class="no">18</span>   <span class="r">end</span>
<span class="no">19</span> 
<span class="no"><strong>20</strong></span>   <span class="c"># Generate class methods to return pre-instantiated</span>
<span class="no">21</span>   <span class="c"># TransactionState objects, one per status name.</span>
<span class="no">22</span>   <span class="r">class</span> &lt;&lt; <span class="cl">self</span>
<span class="no">23</span>     <span class="cv">states_cache</span> = <span class="co">Hash</span>.new
<span class="no">24</span>     <span class="co">StatusNames</span>.each <span class="r">do</span> |status|
<span class="no"><strong>25</strong></span>       <span class="cv">states_cache</span>[status.to_sym] = <span class="co">TransactionState</span>.new(status)
<span class="no">26</span>       define_method(status) <span class="r">do</span>
<span class="no">27</span>         <span class="cv">@states_cache[status.to_sym]

28       end

29     end

30   end

31 

32   Statuses = StatusNames.map {|status| TransactionState.send(status)}

33 end