* lib/rubygems: Update to RubyGems 2.4.5.

* test/rubygems:  ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48729 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/rubygems/request_set/lockfile.rb

@@ -200,6 +200,8 @@ class Gem::RequestSet::Lockfile
 
     platforms = @requests.map { |request| request.spec.platform }.uniq
 
+    platforms = platforms.sort_by { |platform| platform.to_s }
+
     platforms.sort.each do |platform|
       out << "  #{platform}"
     end
@@ -277,14 +279,7 @@ class Gem::RequestSet::Lockfile
       when :bang then
         get :bang
 
-        spec = @set.sets.select { |set|
-          Gem::Resolver::GitSet    === set or
-          Gem::Resolver::VendorSet === set
-        }.map { |set|
-          set.specs[name]
-        }.compact.first
-
-        requirements << spec.version
+        requirements << pinned_requirement(name)
       when :l_paren then
         get :l_paren
 
@@ -300,6 +295,13 @@ class Gem::RequestSet::Lockfile
         end
 
         get :r_paren
+
+        if peek[0] == :bang then
+          requirements.clear
+          requirements << pinned_requirement(name)
+
+          get :bang
+        end
       end
 
       @set.gem name, *requirements
@@ -507,6 +509,17 @@ class Gem::RequestSet::Lockfile
     @tokens.first || [:EOF]
   end
 
+  def pinned_requirement name # :nodoc:
+    spec = @set.sets.select { |set|
+      Gem::Resolver::GitSet    === set or
+        Gem::Resolver::VendorSet === set
+    }.map { |set|
+      set.specs[name]
+    }.compact.first
+
+    spec.version
+  end
+
   def skip type # :nodoc:
     get while not @tokens.empty? and peek.first == type
   end