From 7f71f2c07bc46c741be0c4381497c40296a87eb4 Mon Sep 17 00:00:00 2001
From: noice <noice@email.cz>
Date: Sun, 14 Aug 2011 04:25:59 +0200
Subject: [PATCH] Added support for DataMapper v1.1.0. Including tests.

---
 README.rdoc                                   |  2 +
 kaminari.gemspec                              |  2 +
 .../models/data_mapper_collection_methods.rb  | 23 +++++++
 lib/kaminari/models/data_mapper_extension.rb  | 43 +++++++++++++
 lib/kaminari/railtie.rb                       |  6 ++
 spec/models/data_mapper_spec.rb               | 64 +++++++++++++++++++
 spec/support/matchers.rb                      |  6 ++
 7 files changed, 146 insertions(+)
 create mode 100644 lib/kaminari/models/data_mapper_collection_methods.rb
 create mode 100644 lib/kaminari/models/data_mapper_extension.rb
 create mode 100644 spec/models/data_mapper_spec.rb

diff --git a/README.rdoc b/README.rdoc
index 51f76b1..328349c 100644
--- a/README.rdoc
+++ b/README.rdoc
@@ -37,6 +37,8 @@ The pagination helper outputs the HTML5 <nav> tag by default. Plus, the helper s
 
 * MongoMapper 0.9
 
+* DataMapper 1.1.0
+
 == Install
 
 Put this line in your Gemfile:
diff --git a/kaminari.gemspec b/kaminari.gemspec
index a6fa05f..e075fbf 100644
--- a/kaminari.gemspec
+++ b/kaminari.gemspec
@@ -26,6 +26,8 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'sqlite3', ['>= 0']
   s.add_development_dependency 'mongoid', ['>= 2']
   s.add_development_dependency 'mongo_mapper', ['>= 0.9']
+  s.add_development_dependency 'dm-core', ['>= 1.1.0']
+  s.add_development_dependency 'dm-sqlite-adapter', ['>= 1.1.0']
   s.add_development_dependency 'rspec', ['>= 0']
   s.add_development_dependency 'rspec-rails', ['>= 0']
   s.add_development_dependency 'rr', ['>= 0']
diff --git a/lib/kaminari/models/data_mapper_collection_methods.rb b/lib/kaminari/models/data_mapper_collection_methods.rb
new file mode 100644
index 0000000..f57a103
--- /dev/null
+++ b/lib/kaminari/models/data_mapper_collection_methods.rb
@@ -0,0 +1,23 @@
+module Kaminari
+  module DataMapperCollectionMethods
+    extend ActiveSupport::Concern
+    module InstanceMethods
+      def limit_value #:nodoc:
+        query.options[:limit] || 0
+      end
+
+      def offset_value #:nodoc:
+        query.options[:offset] || 0
+      end
+
+      def total_count #:nodoc:
+        return count if query.options.blank?
+        opts = query.options.dup
+        opts.delete(:limit)
+        opts.delete(:offset)
+        opts.delete(:order)
+        model.all(opts).count
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/lib/kaminari/models/data_mapper_extension.rb b/lib/kaminari/models/data_mapper_extension.rb
new file mode 100644
index 0000000..fdc08d9
--- /dev/null
+++ b/lib/kaminari/models/data_mapper_extension.rb
@@ -0,0 +1,43 @@
+require 'kaminari/models/data_mapper_collection_methods'
+
+module Kaminari
+  module DataMapperExtension
+    module Collection
+      extend ActiveSupport::Concern
+      included do
+        include Kaminari::ConfigurationMethods::ClassMethods
+        include Kaminari::DataMapperCollectionMethods
+        include Kaminari::PageScopeMethods
+
+        # Fetch the values at the specified page number
+        #   Model.all(:some => :conditions).page(5)
+        def page(num)
+          limit(default_per_page).offset(default_per_page * ([num.to_i, 1].max - 1))
+        end
+      end
+    end
+
+    module Model
+      extend ActiveSupport::Concern
+      included do
+        # Fetch the values at the specified page number
+        #   Model.page(5)
+        def page(*args)
+          all.page(*args)
+        end
+
+        def per(*args)
+          all.per(*args)
+        end
+
+        def limit(val)
+          all(:limit => val)
+        end
+
+        def offset(val)
+          all(:offset => val)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/kaminari/railtie.rb b/lib/kaminari/railtie.rb
index a3807a4..e014a17 100644
--- a/lib/kaminari/railtie.rb
+++ b/lib/kaminari/railtie.rb
@@ -2,6 +2,7 @@ require 'rails'
 # ensure ORMs are loaded *before* initializing Kaminari
 begin; require 'mongoid'; rescue LoadError; end
 begin; require 'mongo_mapper'; rescue LoadError; end
+begin; require 'dm-core'; rescue LoadError; end
 
 require 'kaminari/config'
 require 'kaminari/helpers/action_view_extension'
@@ -27,6 +28,11 @@ module Kaminari
         ::Plucky::Query.send :include, Kaminari::PluckyCriteriaMethods
         ::Plucky::Query.send :include, Kaminari::PageScopeMethods
       end
+      if defined? ::DataMapper
+        require 'kaminari/models/data_mapper_extension'
+        ::DataMapper::Model.send :include, Kaminari::DataMapperExtension::Model
+        ::DataMapper::Collection.send :include, Kaminari::DataMapperExtension::Collection
+      end
       require 'kaminari/models/array_extension'
       ActiveSupport.on_load(:action_view) do
         ::ActionView::Base.send :include, Kaminari::ActionViewExtension
diff --git a/spec/models/data_mapper_spec.rb b/spec/models/data_mapper_spec.rb
new file mode 100644
index 0000000..c1a6b1c
--- /dev/null
+++ b/spec/models/data_mapper_spec.rb
@@ -0,0 +1,64 @@
+require File.expand_path('../spec_helper', File.dirname(__FILE__))
+require 'dm-core'
+require 'kaminari/models/data_mapper_extension'
+
+describe Kaminari::DataMapperExtension do
+  before :all do
+    DataMapper.setup(:default, 'sqlite::memory:')
+    class Developer
+      include ::DataMapper::Resource
+      property :id, Serial
+      property :salary, Integer
+    end
+  end
+  before do
+    stub(subject).count { 300 } # in order to avoid DB access...
+  end
+
+  describe '#page' do
+    context 'page 1' do
+      subject { Developer.page(1) }
+      it { should be_a DataMapper::Collection }
+      its(:current_page) { should == 1 }
+      its(:limit_value) { should == 25 }
+      its(:num_pages) { should == 12 }
+      it { should offset(0) }
+    end
+
+    context 'page 2' do
+      subject { Developer.page 2 }
+      it { should be_a DataMapper::Collection }
+      its(:current_page) { should == 2 }
+      its(:limit_value) { should == 25 }
+      its(:num_pages) { should == 12 }
+      it { should offset 25 }
+    end
+
+    context 'page "foobar"' do
+      subject { Developer.page 'foobar' }
+      it { should be_a DataMapper::Collection }
+      its(:current_page) { should == 1 }
+      its(:limit_value) { should == 25 }
+      its(:num_pages) { should == 12 }
+      it { should offset 0 }
+    end
+
+    context 'page 1 with another conditions' do
+      subject { Developer.page(2) }
+      it { should be_a DataMapper::Collection }
+      its(:current_page) { should == 2 }
+      its(:limit_value) { should == 25 }
+      its(:num_pages) { should == 12 }
+      it { should offset(25) }
+    end
+  end
+
+  describe '#per' do
+    subject { Developer.page(2).per(10) }
+    it { should be_a DataMapper::Collection }
+    its(:current_page) { should == 2 }
+    its(:limit_value) { should == 10 }
+    its(:num_pages) { should == 30 }
+    it { should offset 10 }
+  end
+end
diff --git a/spec/support/matchers.rb b/spec/support/matchers.rb
index 4508f38..a10374f 100644
--- a/spec/support/matchers.rb
+++ b/spec/support/matchers.rb
@@ -44,3 +44,9 @@ RSpec::Matchers.define :skip do |num|
     criteria.instance_variable_get('@options')[:skip] == num
   end
 end
+
+RSpec::Matchers.define :offset do |num|
+  match do |collection|
+    collection.offset_value == num
+  end
+end