Added the XML::Attribute class.

This class will replace the use of raw Hash/String values for attributes in
upcoming commits.

lib/oga.rb

@@ -24,6 +24,7 @@ require_relative 'oga/xml/comment'
 require_relative 'oga/xml/cdata'
 require_relative 'oga/xml/xml_declaration'
 require_relative 'oga/xml/doctype'
+require_relative 'oga/xml/attribute'
 require_relative 'oga/xml/node_set'
 
 require_relative 'oga/html/parser'

lib/oga/xml/attribute.rb

@@ -0,0 +1,50 @@
+module Oga
+  module XML
+    ##
+    # Class for storing information about a single XML attribute.
+    #
+    # @!attribute [rw] name
+    #  The name of the attribute.
+    #  @return [String]
+    #
+    # @!attribute [rw] namespace
+    #  The namespace of the attribute.
+    #  @return [String]
+    #
+    # @!attribute [rw] value
+    #  The value of the attribute.
+    #  @return [String]
+    #
+    class Attribute
+      attr_accessor :name, :namespace, :value
+
+      ##
+      # @param [Hash] options
+      #
+      # @option options [String] :name
+      # @option options [String] :namespace
+      # @option options [String] :value
+      #
+      def initialize(options = {})
+        @name      = options[:name]
+        @namespace = options[:namespace]
+        @value     = options[:value]
+      end
+
+      ##
+      # @return [String]
+      #
+      def to_s
+        return value.to_s
+      end
+
+      ##
+      # @return [String]
+      #
+      def inspect
+        return "Attribute(name: #{name.inspect} " \
+          "namespace: #{namespace.inspect} value: #{value.inspect})"
+      end
+    end # Attribute
+  end # XML
+end # Oga

spec/oga/xml/attribute_spec.rb

@@ -0,0 +1,35 @@
+require 'spec_helper'
+
+describe Oga::XML::Attribute do
+  context '#initialize' do
+    example 'set the name' do
+      described_class.new(:name => 'a').name.should == 'a'
+    end
+
+    example 'set the namespace' do
+      described_class.new(:namespace => 'a').namespace.should == 'a'
+    end
+
+    example 'set the value' do
+      described_class.new(:value => 'a').value.should == 'a'
+    end
+  end
+
+  context '#to_s' do
+    example 'return an empty String when there is no value' do
+      described_class.new.to_s.should == ''
+    end
+
+    example 'return the value if it is present' do
+      described_class.new(:value => 'a').to_s.should == 'a'
+    end
+  end
+
+  context '#inspect' do
+    example 'return the inspect value' do
+      obj = described_class.new(:name => 'a', :namespace => 'b', :value => 'c')
+
+      obj.inspect.should == 'Attribute(name: "a" namespace: "b" value: "c")'
+    end
+  end
+end