Added support for should_have_one :through [#115 state:resolved]

lib/shoulda/active_record/macros.rb

@@ -349,10 +349,10 @@ def should_have_many(*associations)
       #   should_have_one :god # unless hindu
       #
       def should_have_one(*associations)
-        dependent = get_options!(associations, :dependent)
+        dependent, through = get_options!(associations, :dependent, :through)
         klass = model_class
         associations.each do |association|
-          matcher = have_one(association).dependent(dependent)
+          matcher = have_one(association).dependent(dependent).through(through)
           should matcher.description do
             assert_accepts(matcher, klass.new)
           end

lib/shoulda/active_record/matchers/association_matcher.rb

@@ -133,7 +133,7 @@ def through_association_valid?
 
         def through_association_exists?
           if through_reflection.nil?
-            "#{model_class.name} does not have any relationship to #{@through}"
+            @missing = "#{model_class.name} does not have any relationship to #{@through}"
             false
           else
             true
@@ -142,10 +142,10 @@ def through_association_exists?
 
         def through_association_correct?
           if @through == reflection.options[:through]
-            "Expected #{model_class.name} to have #{@name} through #{@through}, " <<
-              " but got it through #{reflection.options[:through]}"
             true
           else
+            @missing = "Expected #{model_class.name} to have #{@name} through #{@through}, " <<
+              "but got it through #{reflection.options[:through]}"
             false
           end
         end

test/matchers/active_record/association_matcher_test.rb

@@ -126,7 +126,9 @@ class AssociationMatcherTest < ActiveSupport::TestCase # :nodoc:
       define_model :parent do
         has_many :children
       end
-      assert_rejects @matcher.through(:conceptions), Parent.new
+      assert_rejects @matcher.through(:conceptions),
+        Parent.new,
+        :message => /does not have any relationship to conceptions/
     end
 
     should "reject an association that has the wrong :through option" do
@@ -137,9 +139,12 @@ class AssociationMatcherTest < ActiveSupport::TestCase # :nodoc:
       end
       define_model :parent do
         has_many :conceptions
+        has_many :relationships
         has_many :children, :through => :conceptions
       end
-      assert_rejects @matcher.through(:relationships), Parent.new
+      assert_rejects @matcher.through(:relationships),
+                     Parent.new,
+                     :message => /through relationships, but got it through conceptions/
     end
 
     should "accept an association with a valid :dependent option" do

test/rails_root/app/models/profile.rb

@@ -0,0 +1,2 @@
+class Profile < ActiveRecord::Base
+end

test/rails_root/app/models/registration.rb

@@ -0,0 +1,2 @@
+class Registration < ActiveRecord::Base
+end

test/rails_root/app/models/user.rb

@@ -6,6 +6,8 @@ class User < ActiveRecord::Base
   has_many :friends, :through => :friendships
 
   has_one :address, :as => :addressable, :dependent => :destroy
+  has_one :registration
+  has_one :profile, :through => :registration
 
   named_scope :old,      :conditions => "age > 50"
   named_scope :eighteen, :conditions => { :age => 18 }

test/rails_root/db/migrate/20090506203502_create_profiles.rb

@@ -0,0 +1,12 @@
+class CreateProfiles < ActiveRecord::Migration
+  def self.up
+    create_table :profiles do |t|
+
+      t.timestamps
+    end
+  end
+
+  def self.down
+    drop_table :profiles
+  end
+end

test/rails_root/db/migrate/20090506203536_create_registrations.rb

@@ -0,0 +1,14 @@
+class CreateRegistrations < ActiveRecord::Migration
+  def self.up
+    create_table :registrations do |t|
+      t.integer :user_id
+      t.integer :profile_id
+
+      t.timestamps
+    end
+  end
+
+  def self.down
+    drop_table :registrations
+  end
+end

test/unit/user_test.rb

@@ -66,4 +66,11 @@ class UserTest < ActiveSupport::TestCase
   should_fail do
     should_not_allow_mass_assignment_of :name, :age
   end
+
+  should_have_one :profile, :through => :registration
+
+  should_fail do
+    should_have_one :profile, :through => :interview
+    should_have_one :address, :through => :registration
+  end
 end