diff --git a/middleman-core/spec/middleman-core/binary_spec.rb b/middleman-core/spec/middleman-core/binary_spec.rb
index 1643bd93..79944331 100644
--- a/middleman-core/spec/middleman-core/binary_spec.rb
+++ b/middleman-core/spec/middleman-core/binary_spec.rb
@@ -3,13 +3,13 @@ require 'middleman-core/util'
 describe "Middleman::Util#binary?" do
   %w(plain.txt unicode.txt unicode).each do |file|
     it "recognizes #{file} as not binary" do
-      Middleman::Util.binary?(File.join(File.dirname(__FILE__), "binary_spec/#{file}")).should be_false
+      expect(Middleman::Util.binary?(File.join(File.dirname(__FILE__), "binary_spec/#{file}"))).to be_false
     end
   end
 
   %w(middleman.png middleman stars.svgz).each do |file|
     it "recognizes #{file} as binary" do
-      Middleman::Util.binary?(File.join(File.dirname(__FILE__), "binary_spec/#{file}")).should be_true
+      expect(Middleman::Util.binary?(File.join(File.dirname(__FILE__), "binary_spec/#{file}"))).to be_true
     end
   end
 end