[CompactIndexClient] Synchronize access to the list of fetched endpoints

1 files changed, 6 insertions, 1 deletions

diff --git a/lib/bundler/compact_index_client.rb b/lib/bundler/compact_index_client.rb
index c3a1b69c6f..3ed05ca484 100644
--- a/lib/bundler/compact_index_client.rb
+++ b/lib/bundler/compact_index_client.rb
@@ -29,6 +29,7 @@ module Bundler
       @endpoints = Set.new
       @info_checksums_by_name = {}
       @parsed_checksums = false
+      @mutex = Mutex.new
       @in_parallel = lambda do |inputs, &blk|
         inputs.map(&blk)
       end
@@ -73,7 +74,7 @@ module Bundler
 
     def update(local_path, remote_path)
       Bundler::CompactIndexClient.debug { "update(#{local_path}, #{remote_path})" }
-      unless @endpoints.add?(remote_path)
+      unless synchronize { @endpoints.add?(remote_path) }
         Bundler::CompactIndexClient.debug { "already fetched #{remote_path}" }
         return
       end
@@ -99,5 +100,9 @@ module Bundler
     def url(path)
       path
     end
+
+    def synchronize
+      @mutex.synchronize { yield }
+    end
   end
 end