some refactoring

spec/lib/docker_container_mixin_spec.rb

@@ -1,18 +1,30 @@
 require 'rails_helper'
 
 describe DockerContainerMixin do
-  [:binds, :port_bindings].each do |method|
-    describe "##{method}" do
-      let(:data) { [] }
+  describe '#binds' do
+    let(:binds) { [] }
 
-      it 'is defined for Docker::Container' do
-        expect(Docker::Container.instance_methods).to include(method)
-      end
+    it 'is defined for Docker::Container' do
+      expect(Docker::Container.instance_methods).to include(:binds)
+    end
 
-      it 'returns the correct information' do
-        expect(CONTAINER).to receive(:json).and_return('HostConfig' => {method.to_s.camelize => data})
-        expect(CONTAINER.send(method)).to eq(data)
-      end
+    it 'returns the correct information' do
+      expect(CONTAINER).to receive(:json).and_return('HostConfig' => {'Binds' => binds})
+      expect(CONTAINER.binds).to eq(binds)
+    end
+  end
+
+  describe '#port_bindings' do
+    let(:port) { 1234 }
+    let(:port_bindings) { {"#{port}/tcp" => [{'HostIp' => '', 'HostPort' => port.to_s}]} }
+
+    it 'is defined for Docker::Container' do
+      expect(Docker::Container.instance_methods).to include(:port_bindings)
+    end
+
+    it 'returns the correct information' do
+      expect(CONTAINER).to receive(:json).and_return('HostConfig' => {'PortBindings' => port_bindings})
+      expect(CONTAINER.port_bindings).to eq(port => port)
     end
   end
 end