use semantic Guardfile rules for RSpec

Author: e2

Guardfile

@@ -3,8 +3,17 @@ guard :bundler do
   watch(%r{^.+\.gemspec$})
 end
 
-guard :rspec do
-  watch(%r{^spec/.+_spec\.rb$})
-  watch(%r{^lib/(.+)\.rb$})     { |m| "spec/#{m[1]}_spec.rb" }
-  watch('spec/spec_helper.rb')  { 'spec' }
+guard :rspec, cmd: "bundle exec rspec" do
+  require "ostruct"
+
+  rspec = OpenStruct.new
+  rspec.spec_dir = "spec"
+  rspec.spec = ->(m) { "#{rspec.spec_dir}/#{m}_spec.rb" }
+  rspec.spec_helper = "#{rspec.spec_dir}/spec_helper.rb"
+  rspec.spec_files = %r{^#{rspec.spec_dir}/.+_spec\.rb$}
+  rspec.lib_files = %r{^lib/(.+)\.rb$}
+
+  watch(rspec.spec_files)
+  watch(rspec.lib_files)   { |m| rspec.spec.(m[1]) }
+  watch(rspec.spec_helper) { rspec.spec_dir }
 end