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@@ -1,3 +1,5 @@
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+* Add first/last methods to associations/named_scope. Resolved #226. [Ryan Bates]
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+
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 *2.1.0 RC1 (May 11th, 2008)*
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 * Ensure hm:t preloading honours reflection options. Resolves #137. [Frederick Cheung]

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@@ -48,6 +48,26 @@ module ActiveRecord
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         end
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       end
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+      # fetch first using SQL if possible
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+      def first(*args)
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+        if fetch_first_or_last_using_find? args
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+          find(:first, *args)
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+        else
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+          load_target unless loaded?
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+          @target.first(*args)
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+        end
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+      end
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+
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+      # fetch last using SQL if possible
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+      def last(*args)
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+        if fetch_first_or_last_using_find? args
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+          find(:last, *args)
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+        else
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+          load_target unless loaded?
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+          @target.last(*args)
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+        end
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+      end
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+
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       def to_ary
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         load_target
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         @target.to_ary
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@@ -330,7 +350,10 @@ module ActiveRecord
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             raise ActiveRecord::RecordNotSaved, "You cannot call create unless the parent is saved"
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           end
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         end
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-               
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+
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+        def fetch_first_or_last_using_find?(args)
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+          args.first.kind_of?(Hash) || !(loaded? || @owner.new_record? || @reflection.options[:finder_sql] || !@target.blank? || args.first.kind_of?(Integer))
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+        end
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     end
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   end
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 end

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@@ -102,7 +102,13 @@ module ActiveRecord
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     class Scope
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       attr_reader :proxy_scope, :proxy_options
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-      [].methods.each { |m| delegate m, :to => :proxy_found unless m =~ /(^__|^nil\?|^send|^object_id$|class|extend|find|count|sum|average|maximum|minimum|paginate)/ }
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+
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+      [].methods.each do |m|
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+        unless m =~ /(^__|^nil\?|^send|^object_id$|class|extend|find|count|sum|average|maximum|minimum|paginate|first|last)/
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+          delegate m, :to => :proxy_found
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+        end
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+      end
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+
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       delegate :scopes, :with_scope, :to => :proxy_scope
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       def initialize(proxy_scope, options, &block)
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@@ -115,6 +121,22 @@ module ActiveRecord
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         load_found; self
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       end
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+      def first(*args)
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+        if args.first.kind_of?(Integer) || (@found && !args.first.kind_of?(Hash))
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+          proxy_found.first(*args)
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+        else
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+          find(:first, *args)
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+        end
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+      end
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+
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+      def last(*args)
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+        if args.first.kind_of?(Integer) || (@found && !args.first.kind_of?(Hash))
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+          proxy_found.last(*args)
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+        else
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+          find(:last, *args)
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+        end
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+      end
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+
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       protected
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       def proxy_found
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         @found || load_found

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@@ -401,6 +401,8 @@ class HasAndBelongsToManyAssociationsTest < ActiveRecord::TestCase
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   def test_include_uses_array_include_after_loaded
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     project = projects(:active_record)
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+    project.developers.class # force load target
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+
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     developer = project.developers.first
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     assert_no_queries do

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@@ -818,6 +818,8 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
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   def test_include_uses_array_include_after_loaded
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     firm = companies(:first_firm)
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+    firm.clients.class # force load target
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+
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     client = firm.clients.first
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     assert_no_queries do
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@@ -857,4 +859,68 @@ class HasManyAssociationsTest < ActiveRecord::TestCase
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     assert ! firm.clients.include?(client)
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   end
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+  def test_calling_first_or_last_on_association_should_not_load_association
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+    firm = companies(:first_firm)
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+    firm.clients.first
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+    firm.clients.last
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+    assert !firm.clients.loaded?
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+  end
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+
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+  def test_calling_first_or_last_on_loaded_association_should_not_fetch_with_query
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+    firm = companies(:first_firm)
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+    firm.clients.class # force load target
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+    assert firm.clients.loaded?
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+
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+    assert_no_queries do
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+      firm.clients.first
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+      assert_equal 2, firm.clients.first(2).size
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+      firm.clients.last
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+      assert_equal 2, firm.clients.last(2).size
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+    end
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+  end
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+
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+  def test_calling_first_or_last_on_existing_record_with_build_should_load_association
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+    firm = companies(:first_firm)
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+    firm.clients.build(:name => 'Foo')
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+    assert !firm.clients.loaded?
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+
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+    assert_queries 1 do
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+      firm.clients.first
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+      firm.clients.last
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+    end
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+
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+    assert firm.clients.loaded?
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+  end
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+
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+  def test_calling_first_or_last_on_new_record_should_not_run_queries
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+    firm = Firm.new
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+
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+    assert_no_queries do
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+      firm.clients.first
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+      firm.clients.last
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+    end
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+  end
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+
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+  def test_calling_first_or_last_with_find_options_on_loaded_association_should_fetch_with_query
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+    firm = companies(:first_firm)
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+    firm.clients.class # force load target
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+
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+    assert_queries 2 do
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+      assert firm.clients.loaded?
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+      firm.clients.first(:order => 'name')
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+      firm.clients.last(:order => 'name')
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+    end
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+  end
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+
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+  def test_calling_first_or_last_with_integer_on_association_should_load_association
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+    firm = companies(:first_firm)
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+
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+    assert_queries 1 do
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+      firm.clients.first(2)
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+      firm.clients.last(2)
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+    end
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+
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+    assert firm.clients.loaded?
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+  end
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+
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 end

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@@ -664,6 +664,8 @@ class AssociationsJoinModelTest < ActiveRecord::TestCase
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   def test_has_many_through_include_uses_array_include_after_loaded
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     david = authors(:david)
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+    david.categories.class # force load target
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+
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     category = david.categories.first
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     assert_no_queries do

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@@ -99,12 +99,12 @@ class AssociationProxyTest < ActiveRecord::TestCase
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     david = authors(:david)
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     assert_equal  david, david.posts.proxy_owner
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     assert_equal  david.class.reflect_on_association(:posts), david.posts.proxy_reflection
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-    david.posts.first   # force load target
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+    david.posts.class   # force load target
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     assert_equal  david.posts, david.posts.proxy_target
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     assert_equal  david, david.posts_with_extension.testing_proxy_owner
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     assert_equal  david.class.reflect_on_association(:posts_with_extension), david.posts_with_extension.testing_proxy_reflection
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-    david.posts_with_extension.first   # force load target
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+    david.posts_with_extension.class   # force load target
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     assert_equal  david.posts_with_extension, david.posts_with_extension.testing_proxy_target
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   end
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@@ -118,4 +118,32 @@ class NamedScopeTest < ActiveRecord::TestCase
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     assert_equal expected_proxy_options, Topic.approved.proxy_options
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   end
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+  def test_first_and_last_should_support_find_options
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+    assert_equal Topic.base.first(:order => 'title'), Topic.base.find(:first, :order => 'title')
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+    assert_equal Topic.base.last(:order => 'title'), Topic.base.find(:last, :order => 'title')
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+  end
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+
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+  def test_first_and_last_should_allow_integers_for_limit
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+    assert_equal Topic.base.first(2), Topic.base.to_a.first(2)
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+    assert_equal Topic.base.last(2), Topic.base.to_a.last(2)
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+  end
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+
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+  def test_first_and_last_should_not_use_query_when_results_are_loaded
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+    topics = Topic.base
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+    topics.reload # force load
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+    assert_no_queries do
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+      topics.first
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+      topics.last
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+    end
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+  end
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+
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+  def test_first_and_last_find_options_should_use_query_when_results_are_loaded
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+    topics = Topic.base
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+    topics.reload # force load
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+    assert_queries(2) do
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+      topics.first(:order => 'title')
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+      topics.last(:order => 'title')
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+    end
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+  end
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+
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 end