[ruby/English] Exclude unused files from gem

ruby/English@6bea25038b

Author: nobu

lib/English.gemspec

@@ -15,8 +15,13 @@ Gem::Specification.new do |spec|
 
   # Specify which files should be added to the gem when it is released.
   # The `git ls-files -z` loads the files in the RubyGem that have been added into git.
-  spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
-    `git ls-files -z 2>#{IO::NULL}`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
+  excludes = %W[
+    :^/test :^/spec :^/feature :^/bin
+    :^/Rakefile :^/Gemfile\* :^/.git*
+    :^/#{File.basename(__FILE__)}
+  ]
+  spec.files = IO.popen(%W[git ls-files -z --] + excludes, err: IO::NULL) do |f|
+    f.readlines("\x0", chomp: true)
   end
   spec.require_paths = ["lib"]
 end