diff --git a/Gemfile.lock b/Gemfile.lock
index 2dce4cf..554365d 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,39 +2,41 @@ GEM
   remote: https://rubygems.org/
   specs:
     base64 (0.3.0)
-    date (3.4.1)
+    date (3.5.1)
     diff-lcs (1.6.2)
     docile (1.4.1)
-    erb (5.0.2)
-    psych (5.2.6)
+    erb (6.0.1)
+    psych (5.3.1)
       date
       stringio
-    rake (13.3.0)
-    rdoc (6.14.2)
+    rake (13.3.1)
+    rdoc (7.1.0)
       erb
       psych (>= 4.0.0)
+      tsort
     redcarpet (3.6.1)
-    rspec (3.13.1)
+    rspec (3.13.2)
       rspec-core (~> 3.13.0)
       rspec-expectations (~> 3.13.0)
       rspec-mocks (~> 3.13.0)
-    rspec-core (3.13.5)
+    rspec-core (3.13.6)
       rspec-support (~> 3.13.0)
     rspec-expectations (3.13.5)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-mocks (3.13.5)
+    rspec-mocks (3.13.7)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-support (3.13.4)
+    rspec-support (3.13.6)
     simplecov (0.22.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
     simplecov-html (0.13.2)
     simplecov_json_formatter (0.1.4)
-    stringio (3.1.7)
+    stringio (3.2.0)
     syntax (1.2.2)
+    tsort (0.2.0)
 
 PLATFORMS
   ruby