Add comment that gemspec is generated automatically

1 files changed, 4 insertions, 1 deletions

diff --git a/Rakefile b/Rakefile
index 12938c7..fed7f8e 100644
--- a/Rakefile
+++ b/Rakefile
@@ -106,7 +106,10 @@ if defined?(Gem) and defined?(Gem::PackageTask)
   desc 'Creates a json_pure.gemspec file'
   task :gemspec_pure => :version do
     File.open('json_pure.gemspec', 'w') do |gemspec|
-      gemspec.write spec_pure.to_ruby
+      src = spec_pure.to_ruby
+      src.gsub!(/# stub:.*/, "# This gemspec is generated automatically using `rake gemspec`.\n" \
+                             "# Do not modify directly.")
+      gemspec.write src
     end
   end