Make Bundler::RemoteSpecification comparable.

Uses a comparison strategy borrowed from RubyGems 2.23 for maximum 
compatibility with Gem::Specification et. al.

1 files changed, 18 insertions, 2 deletions

diff --git a/lib/bundler/remote_specification.rb b/lib/bundler/remote_specification.rb
index d8bd5c331f..36f62af7e4 100644
--- a/lib/bundler/remote_specification.rb
+++ b/lib/bundler/remote_specification.rb
@@ -34,9 +34,12 @@ module Bundler
       end
     end
 
+    # Compare this specification against another object. Using sort_obj
+    # is compatible with Gem::Specification and other Bundler or RubyGems
+    # objects. Otherwise, use the default Object comparison.
     def <=>(other)
-      if other.respond_to?(:full_name)
-        full_name <=> other.full_name
+      if other.respond_to?(:sort_obj)
+        sort_obj <=> other.sort_obj
       else
         super
       end
@@ -51,6 +54,19 @@ module Bundler
 
   private
 
+    # Create a delegate used for sorting. This strategy is copied from
+    # RubyGems 2.23 and ensures that Bundler's specifications can be
+    # compared and sorted with RubyGems' own specifications.
+    #
+    # @see #<=>
+    # @see Gem::Specification#sort_obj
+    #
+    # @return [Array] an object you can use to compare and sort this
+    #   specification against other specifications
+    def sort_obj
+      [@name, @version, @platform == Gem::Platform::RUBY ? -1 : 1]
+    end
+
     def _remote_specification
       @_remote_specification ||= @spec_fetcher.fetch_spec([@name, @version, @platform])
     end