lib/bundler/definition.rb in bundler-1.10.4 vs lib/bundler/definition.rb in bundler-1.10.5

@@ -246,24 +246,25 @@
 
       # Convert to \r\n if the existing lock has them
       # i.e., Windows with `git config core.autocrlf=true`
       contents.gsub!(/\n/, "\r\n") if @lockfile_contents.match("\r\n")
 
-      return if lockfiles_equal?(@lockfile_contents, contents, preserve_bundled_with)
-
-      if Bundler.settings[:frozen]
-        Bundler.ui.error "Cannot write a changed lockfile while frozen."
-        return
-      end
-
       if @locked_bundler_version
         locked_major = @locked_bundler_version.segments.first
         current_major = Gem::Version.create(Bundler::VERSION).segments.first
 
-        if locked_major < current_major
-          Bundler.ui.warn "Warning: the lockfile is being updated to Bundler #{Bundler::VERSION.split('.').first}, " \
+        if updating_major = locked_major < current_major
+          Bundler.ui.warn "Warning: the lockfile is being updated to Bundler #{current_major}, " \
                           "after which you will be unable to return to Bundler #{@locked_bundler_version.segments.first}."
         end
+      end
+
+      preserve_bundled_with ||= !updating_major && (Bundler.settings[:frozen] || !@unlocking)
+      return if lockfiles_equal?(@lockfile_contents, contents, preserve_bundled_with)
+
+      if Bundler.settings[:frozen]
+        Bundler.ui.error "Cannot write a changed lockfile while frozen."
+        return
       end
 
       File.open(file, 'wb'){|f| f.puts(contents) }
     rescue Errno::EACCES
       raise Bundler::InstallError,