From 613ab1c1abb1338d873eb3ffccb9df355685a2c1 Mon Sep 17 00:00:00 2001
From: Ryan Bates <ryan@railscasts.com>
Date: Sat, 21 May 2011 13:57:17 -0700
Subject: [PATCH] delegating ControllerResource find to model adapter, uses
 'get' for DataMapper - closes #373

---
 lib/cancan/controller_resource.rb                        | 6 +++++-
 lib/cancan/model_adapters/abstract_adapter.rb            | 5 +++++
 lib/cancan/model_adapters/data_mapper_adapter.rb         | 4 ++++
 spec/cancan/model_adapters/active_record_adapter_spec.rb | 5 +++++
 spec/cancan/model_adapters/data_mapper_adapter_spec.rb   | 5 +++++
 spec/cancan/model_adapters/mongoid_adapter_spec.rb       | 5 +++++
 6 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/lib/cancan/controller_resource.rb b/lib/cancan/controller_resource.rb
index 10cf4b6..6c41efd 100644
--- a/lib/cancan/controller_resource.rb
+++ b/lib/cancan/controller_resource.rb
@@ -107,11 +107,15 @@ module CanCan
             resource_base.send(@options[:find_by], id_param)
           end
         else
-          resource_base.find(id_param)
+          adapter.find(resource_base, id_param)
         end
       end
     end
 
+    def adapter
+      ModelAdapters::AbstractAdapter.adapter_class(resource_class)
+    end
+
     def authorization_action
       parent? ? :show : @params[:action].to_sym
     end
diff --git a/lib/cancan/model_adapters/abstract_adapter.rb b/lib/cancan/model_adapters/abstract_adapter.rb
index 2b7b873..e644713 100644
--- a/lib/cancan/model_adapters/abstract_adapter.rb
+++ b/lib/cancan/model_adapters/abstract_adapter.rb
@@ -15,6 +15,11 @@ module CanCan
         false # override in subclass
       end
 
+      # Override if you need custom find behavior
+      def self.find(model_class, id)
+        model_class.find(id)
+      end
+
       # Used to determine if this model adapter will override the matching behavior for a hash of conditions.
       # If this returns true then matches_conditions_hash? will be called. See Rule#matches_conditions_hash
       def self.override_conditions_hash_matching?(subject, conditions)
diff --git a/lib/cancan/model_adapters/data_mapper_adapter.rb b/lib/cancan/model_adapters/data_mapper_adapter.rb
index 88058db..c36c51a 100644
--- a/lib/cancan/model_adapters/data_mapper_adapter.rb
+++ b/lib/cancan/model_adapters/data_mapper_adapter.rb
@@ -5,6 +5,10 @@ module CanCan
         model_class <= DataMapper::Resource
       end
 
+      def self.find(model_class, id)
+        model_class.get(id)
+      end
+
       def self.override_conditions_hash_matching?(subject, conditions)
         conditions.any? { |k,v| !k.kind_of?(Symbol) }
       end
diff --git a/spec/cancan/model_adapters/active_record_adapter_spec.rb b/spec/cancan/model_adapters/active_record_adapter_spec.rb
index fc8c8a4..cf4155b 100644
--- a/spec/cancan/model_adapters/active_record_adapter_spec.rb
+++ b/spec/cancan/model_adapters/active_record_adapter_spec.rb
@@ -56,6 +56,11 @@ if ENV["MODEL_ADAPTER"].nil? || ENV["MODEL_ADAPTER"] == "active_record"
       CanCan::ModelAdapters::AbstractAdapter.adapter_class(Article).should == CanCan::ModelAdapters::ActiveRecordAdapter
     end
 
+    it "should find record" do
+      article = Article.create!
+      CanCan::ModelAdapters::ActiveRecordAdapter.find(Article, article.id).should == article
+    end
+
     it "should not fetch any records when no abilities are defined" do
       Article.create!
       Article.accessible_by(@ability).should be_empty
diff --git a/spec/cancan/model_adapters/data_mapper_adapter_spec.rb b/spec/cancan/model_adapters/data_mapper_adapter_spec.rb
index e2eb1f8..6c6c7f1 100644
--- a/spec/cancan/model_adapters/data_mapper_adapter_spec.rb
+++ b/spec/cancan/model_adapters/data_mapper_adapter_spec.rb
@@ -36,6 +36,11 @@ if ENV["MODEL_ADAPTER"] == "data_mapper"
       CanCan::ModelAdapters::AbstractAdapter.adapter_class(Article).should == CanCan::ModelAdapters::DataMapperAdapter
     end
 
+    it "should find record" do
+      article = Article.create
+      CanCan::ModelAdapters::DataMapperAdapter.find(Article, article.id).should == article
+    end
+
     it "should not fetch any records when no abilities are defined" do
       Article.create
       Article.accessible_by(@ability).should be_empty
diff --git a/spec/cancan/model_adapters/mongoid_adapter_spec.rb b/spec/cancan/model_adapters/mongoid_adapter_spec.rb
index 1ce0466..fc53d23 100644
--- a/spec/cancan/model_adapters/mongoid_adapter_spec.rb
+++ b/spec/cancan/model_adapters/mongoid_adapter_spec.rb
@@ -36,6 +36,11 @@ if ENV["MODEL_ADAPTER"] == "mongoid"
         CanCan::ModelAdapters::AbstractAdapter.adapter_class(MongoidProject).should == CanCan::ModelAdapters::MongoidAdapter
       end
 
+      it "should find record" do
+        project = MongoidProject.create
+        CanCan::ModelAdapters::MongoidAdapter.find(MongoidProject, project.id).should == project
+      end
+
       it "should compare properties on mongoid documents with the conditions hash" do
         model = MongoidProject.new
         @ability.can :read, MongoidProject, :id => model.id