Move Rubocop development dependency into gemspec

Now that Bundler no longer supports Ruby <2.3, the Ruby minimum version
requirement that prevented Rubocop from being specified as a development
dependency in the gemspec no longer applies.

Having Rubocop in the gemspec is useful for tools like RubyGems.org or
Bundix that use it as the source of truth for dependencies.

2 files changed, 4 insertions, 8 deletions

diff --git a/Rakefile b/Rakefile
index 746d110f86..21b11b9e59 100644
--- a/Rakefile
+++ b/Rakefile
@@ -43,7 +43,6 @@ namespace :spec do
     deps = Hash[bundler_spec.development_dependencies.map do |d|
       [d.name, d.requirement.to_s]
     end]
-    deps["rubocop"] ||= "= 0.50.0" if RUBY_VERSION >= "2.0.0" # can't go in the gemspec because of the ruby version requirement
 
     # JRuby can't build ronn or rdiscount, so we skip that
     if defined?(RUBY_ENGINE) && RUBY_ENGINE == "jruby"
@@ -95,13 +94,9 @@ begin
   RSpec::Core::RakeTask.new
   task :spec => "man:build"
 
-  if RUBY_VERSION >= "2.0.0"
-    # can't go in the gemspec because of the ruby version requirement
-    gem "rubocop", "= 0.50.0"
-    require "rubocop/rake_task"
-    rubocop = RuboCop::RakeTask.new
-    rubocop.options = ["--parallel"]
-  end
+  require "rubocop/rake_task"
+  rubocop = RuboCop::RakeTask.new
+  rubocop.options = ["--parallel"]
 
   namespace :spec do
     task :clean do
diff --git a/bundler.gemspec b/bundler.gemspec
index 12b1b59b98..3a87b8713c 100644
--- a/bundler.gemspec
+++ b/bundler.gemspec
@@ -46,6 +46,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rdiscount",  "~> 2.2"
   s.add_development_dependency "ronn",       "~> 0.7.3"
   s.add_development_dependency "rspec",      "~> 3.6"
+  s.add_development_dependency "rubocop",    "= 0.50.0"
 
   base_dir = File.dirname(__FILE__).gsub(%r{([^A-Za-z0-9_\-.,:\/@\n])}, "\\\\\\1")
   s.files = IO.popen("git -C #{base_dir} ls-files -z", &:read).split("\x0").select {|f| f.match(%r{^(lib|exe)/}) }