add spec for CodeRay.coderay_path

Author: korny

spec/coderay_spec.rb

@@ -1,9 +1,16 @@
 require File.expand_path('../spec_helper', __FILE__)
 
 RSpec.describe CodeRay do
-  describe 'version' do
+  describe '::VERSION' do
     it "returns the Gem's version" do
       expect(CodeRay::VERSION).to match(/\A\d\.\d\.\d?\z/)
     end
   end
+
+  describe '.coderay_path' do
+    it 'returns an absolute file path to the given code file' do
+      base = File.expand_path('../..', __FILE__)
+      expect(CodeRay.coderay_path('file')).to eq("#{base}/lib/coderay/file")
+    end
+  end
 end