Add dataset_spec and repository_spec.

Gemfile

@@ -2,8 +2,8 @@ source "http://rubygems.org"
 
 gemspec
 
-gem "rdf",            git: "git://github.com/ruby-rdf/rdf.git",            branch: "develop"
-gem "rdf-isomorphic", git: "git://github.com/ruby-rdf/rdf-isomorphic.git", branch: "develop"
+gem 'rdf',            github: "ruby-rdf/rdf",             branch: "develop"
+gem 'rdf-isomorphic', github: "ruby-rdf/rdf-isomorphic",  branch: "develop"
 
 group :development do
   gem "wirble"

lib/rdf/spec/dataset.rb

@@ -7,7 +7,7 @@
     raise 'dataset must be set with `let(:dataset)' unless
       defined? dataset
 
-    if repository.empty?
+    if dataset.empty?
       raise "+dataset+ must respond be pre-populated with the statements in #{RDF::Spec::TRIPLES_FILE} in a before block"
     end
   end

lib/rdf/spec/repository.rb

@@ -16,7 +16,7 @@
   end
 
   let(:mutable) { repository }
-  let(:dataset) { repository }
+  let(:dataset) { repository.supports?(:snapshots) ? repository.snapshot : repository }
   subject { repository }
 
   context 'as dataset' do

spec/dataset_spec.rb

@@ -0,0 +1,14 @@
+require File.join(File.dirname(__FILE__), 'spec_helper')
+require 'rdf/spec/dataset'
+
+describe RDF::Dataset do
+
+  let(:dataset) do
+    RDF::Repository.new do |r|
+      r.insert(*RDF::Spec.quads)
+    end.snapshot
+  end
+
+  # @see lib/rdf/spec/dataset.rb in rdf-spec
+  it_behaves_like 'an RDF::Dataset'
+end

spec/repository_spec.rb

@@ -0,0 +1,11 @@
+require File.join(File.dirname(__FILE__), 'spec_helper')
+require 'rdf/spec/repository'
+
+describe RDF::Repository do
+  # @see lib/rdf/spec/repository.rb in rdf-spec
+  it_behaves_like 'an RDF::Repository' do
+    # The available reference implementations are `RDF::Repository` and
+    # `RDF::Graph`, but a plain Ruby array will do fine as well:
+    let(:repository) { RDF::Repository.new }
+  end
+end