(voxpupuli#78) Add tests for facter version

Previously many factset files were in the wrong directory which made maintenance
and debugging difficult.  This commit adds tests to ensure that the factset
files are indeed JSON parsable and that the facter version in the file matches
the directory it is located in.

This test is maked as skipped until all of the bad factset files can be changed.

spec/facts_spec.rb

@@ -11,6 +11,34 @@
   end
 end
 
+RSpec::Matchers.define :be_valid_json do
+  match do |actual|
+    content = File.open(actual, 'rb') { |file| file.read }
+    valid = false
+    begin
+      obj = JSON.parse(content)
+      valid = true
+    rescue JSON::ParserError => e
+      raise "Invalid JSON file #{actual}.\n#{e}"
+    end
+  end
+
+  failure_message do |actual|
+    "expected that fact file #{actual} was a valid JSON file."
+  end
+end
+
+RSpec::Matchers.define :have_facter_version do |expected_facter_version, filepath|
+  match do |actual|
+    # Simple but naive regex check
+    actual =~ /^#{expected_facter_version}($|\.)/
+  end
+
+  failure_message do |actual|
+    "expected that fact file #{filepath} with facter version #{actual} had a facter version that matched #{expected_facter_version}"
+  end
+end
+
 describe 'Default Facts' do
   before(:each) do
     ENV['FACTERDB_SKIP_DEFAULTDB'] = nil
@@ -31,5 +59,23 @@
         expect(file_hashes[file_hash]).to have_a_unique_hash
       end
     end
+
+    it 'should contain fact sets which match are valid JSON' do
+      FacterDB.default_fact_files.each do |filepath|
+        expect(filepath).to be_valid_json
+      end
+    end
+
+    xit 'should contain fact sets which match the facter version' do
+      FacterDB.default_fact_files.each do |filepath|
+        facter_dir_path = File.basename(File.dirname(filepath))
+
+        content = File.open(filepath, 'rb') { |file| file.read }
+        obj = JSON.parse(content)
+        file_facter_version = obj['facterversion']
+
+        expect(file_facter_version).to have_facter_version(facter_dir_path, filepath)
+      end
+    end
   end
 end