Rails DB Connections

first.rb

# This spec fails when I run it for (JRuby + sqlite), but not (Ruby 1.9.3 + [mysql | postgres])
#
# some_model.rb
describe SomeModel
  it { should have_db_index(:name).unique(true) }
end


# Even though the schema.rb shows the db field as unquiely indexed.
#
# schema.rb
ActiveRecord::Schema.define(:version => 20120908004000) do
  create_table "some_model", :force => true do |t|
    t.string   "name",       :limit => 63, :null => false
  end

  add_index "apps", ["name"], :name => "index_apps_on_name", :unique => true
end

# The issue seems to be that MySQL and Postgres connection adapters behave differently than the Sqlite. 
# So I did some digging.
# The shoulda matchers use this to evaluate index uniqueness.
# 
::ActiveRecord::Base.connection.indexes(App.table_name).detect {|e| e.columns == ["name"]}

# The respective results

# mysql2
<struct ActiveRecord::ConnectionAdapters::IndexDefinition table="apps", name="index_apps_on_name", unique=7, columns=["name"], lengths=nil, orders=nil>
# mysql
<struct ActiveRecord::ConnectionAdapters::IndexDefinition table="apps", name="index_apps_on_name", unique=true, columns=["name"], lengths=[nil], orders=nil>
# postgres
<struct ActiveRecord::ConnectionAdapters::IndexDefinition table="apps", name="index_apps_on_name", unique=true, columns=["name"], lengths=nil, orders=nil>

# The difference is mysql2: unqiue = true, pg: unique =  true, sqlite: unique = 7. 
#
# 1) Is Sqlite unique supposed to be 7? I don't think so.
# 
# 2) If not, anyone know where would I go to refactor this? 
#   Somewhere in ActiveRecord::ConnectionAdapters::SQLiteAdapter? 
#   I tried looking in api.rubyonrails.org, but PG was the only adapter 
#   with the [indexes method]((http://api.rubyonrails.org/classes/ActiveRecord/ConnectionAdapters/PostgreSQLAdapter.html#method-i-indexes)).