Add datamapper transformer. Closes #10.

Author: rsutphin

CHANGELOG.markdown

@@ -6,6 +6,8 @@ Bcdatabase history
 
 - Introduce "transforms" -- a way to attach behavior to modify entries
   on load. See {Bcdatabase.load} for details.
+- Add `:datamapper` built-in transform to support sharing one set of
+  entries between ActiveRecord and DataMapper. (#10)
 
 1.0.6
 -----

lib/bcdatabase.rb

@@ -100,6 +100,9 @@ class DatabaseConfigurations
       },
       :decrypt => lambda { |entry, name, group|
         entry.merge({ 'password' => Bcdatabase.decrypt(entry['epassword']) }) if entry['epassword']
+      },
+      :datamapper => lambda { |entry, name, group|
+        entry.merge('adapter' => entry['datamapper_adapter']) if entry['datamapper_adapter']
       }
     }
 

spec/bcdatabase_spec.rb

@@ -214,6 +214,29 @@
         bcdb['scran', 'jim']['foo'].should == ['baz', 'jim', 'scran']
       end
     end
+
+    describe 'for datamapper' do
+      it 'uses the datamapper adapter, if provided' do
+        temporary_yaml 'foo', {
+          'aleph' => {
+            'datamapper_adapter' => 'postgres',
+            'adapter' => 'postgresql'
+          }
+        }
+        bcdb = Bcdatabase.load(:transforms => [:datamapper])
+        bcdb['foo', 'aleph']['adapter'].should == 'postgres'
+      end
+
+      it 'uses the named adapter if no datamapper adapter is provided' do
+        temporary_yaml 'foo', {
+          'aleph' => {
+            'adapter' => 'postgresql'
+          }
+        }
+        bcdb = Bcdatabase.load(:transforms => [:datamapper])
+        bcdb['foo', 'aleph']['adapter'].should == 'postgresql'
+      end
+    end
   end
 
   describe "for database.yml" do