Merge upstream revision of rubygems/rubygems.

  This commits includes tiny bugfix and new features listed here:
    * Add --re-sign flag to cert command by bronzdoc: https://github.com/rubygems/rubygems/pull/2391
    * Download gems with threads. by indirect: https://github.com/rubygems/rubygems/pull/1898

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64769 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 27 insertions, 0 deletions

diff --git a/lib/rubygems/request_set.rb b/lib/rubygems/request_set.rb
index ed99d29295..c68e40ee9e 100644
--- a/lib/rubygems/request_set.rb
+++ b/lib/rubygems/request_set.rb
@@ -152,7 +152,34 @@ class Gem::RequestSet
     @prerelease = options[:prerelease]
 
     requests = []
+    download_queue = Queue.new
 
+    # Create a thread-safe list of gems to download
+    sorted_requests.each do |req|
+      download_queue << req
+    end
+
+    # Create N threads in a pool, have them download all the gems
+    threads = Gem.configuration.concurrent_downloads.times.map do
+      # When a thread pops this item, it knows to stop running. The symbol
+      # is queued here so that there will be one symbol per thread.
+      download_queue << :stop
+
+      Thread.new do
+        # The pop method will block waiting for items, so the only way
+        # to stop a thread from running is to provide a final item that
+        # means the thread should stop.
+        while req = download_queue.pop
+          break if req == :stop
+          req.spec.download options unless req.installed?
+        end
+      end
+    end
+
+    # Wait for all the downloads to finish before continuing
+    threads.each(&:value)
+
+    # Install requested gems after they have been downloaded
     sorted_requests.each do |req|
       if req.installed? then
         req.spec.spec.build_extensions