Remove method_missing, provide methods for repo metadata

Instead of method_missing, methods for each output item from
`yum repolist` are provided.

Signed-off-by: Adam Leff <adam@leff.co>

lib/resources/yum.rb

@@ -133,8 +133,20 @@ module Inspec::Resources
       info['status'] == 'enabled'
     end
 
-    def method_missing(name)
-      info[name.to_s]
+    # provide a method for each of the repo metadata items we know about
+    [
+      :baseurl,
+      :expire,
+      :filename,
+      :mirrors,
+      :pkgs,
+      :size,
+      :status,
+      :updated,
+    ].each do |key|
+      define_method key do
+        info[key.to_s]
+      end
     end
 
     def to_s

test/unit/resources/yum_test.rb

@@ -63,6 +63,19 @@ describe 'Inspec::Resources::YumRepo' do
     _(extras.to_s).must_equal 'YumRepo base-debuginfo/x86_64'
   end
 
+  it 'provides methods for retrieving per-repo information' do
+    resource = MockLoader.new(:centos7).load_resource('yum')
+    repo = resource.repo('base/7/x86_64')
+    _(repo.baseurl).must_equal 'http://ftp.hosteurope.de/mirror/centos.org/7.1.1503/os/x86_64/ (9 more)'
+    _(repo.expire).must_equal '21600 second(s) (last: Sun Sep  6 10:20:46 2015)'
+    _(repo.filename).must_equal '/etc/yum.repos.d/CentOS-Base.repo'
+    _(repo.mirrors).must_equal 'http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=stock'
+    _(repo.pkgs).must_equal '8652'
+    _(repo.size).must_equal '6.3 G'
+    _(repo.status).must_equal 'enabled'
+    _(repo.updated).must_equal 'Tue Mar 31 22:50:46 2015'
+  end
+
   it 'test enabled extra repo (serverspec backwards comptability)' do
     serverspec = load_resource('yumrepo', 'extras')
     _(serverspec.exists?).must_equal true