diff --git a/Gemfile b/Gemfile
index 64e14fd..7f49d7e 100644
--- a/Gemfile
+++ b/Gemfile
@@ -6,7 +6,7 @@ source "https://rubygems.org"
 # `dev` uses no gems
 
 group :development, :test do
-  gem "rubocop", "~> 1.13.0"
+  gem "rubocop", "~> 1.50.2"
   gem "rubocop-performance"
   gem "rubocop-minitest"
   gem "rubocop-rake"
diff --git a/Gemfile.lock b/Gemfile.lock
index 0bfbbba..b45bc6a 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -4,6 +4,7 @@ GEM
     ansi (1.5.0)
     ast (2.4.2)
     builder (3.2.4)
+    json (2.7.2)
     minitest (5.17.0)
     minitest-reporters (1.6.1)
       ansi
@@ -12,24 +13,28 @@ GEM
       ruby-progressbar
     mocha (2.0.2)
       ruby2_keywords (>= 0.0.5)
-    parallel (1.22.1)
-    parser (3.2.0.0)
+    parallel (1.24.0)
+    parser (3.3.1.0)
       ast (~> 2.4.1)
+      racc
+    racc (1.7.3)
     rainbow (3.1.1)
     rake (13.2.1)
-    regexp_parser (2.7.0)
-    rexml (3.2.5)
-    rubocop (1.13.0)
+    regexp_parser (2.9.2)
+    rexml (3.2.8)
+      strscan (>= 3.0.9)
+    rubocop (1.50.2)
+      json (~> 2.3)
       parallel (~> 1.10)
-      parser (>= 3.0.0.0)
+      parser (>= 3.2.0.0)
       rainbow (>= 2.2.2, < 4.0)
       regexp_parser (>= 1.8, < 3.0)
-      rexml
-      rubocop-ast (>= 1.2.0, < 2.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.28.0, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 1.4.0, < 3.0)
-    rubocop-ast (1.24.1)
-      parser (>= 3.1.1.0)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.30.0)
+      parser (>= 3.2.1.0)
     rubocop-minitest (0.27.0)
       rubocop (>= 0.90, < 2.0)
     rubocop-performance (1.16.0)
@@ -41,7 +46,8 @@ GEM
       rubocop (~> 1.11)
     ruby-progressbar (1.13.0)
     ruby2_keywords (0.0.5)
-    unicode-display_width (2.4.2)
+    strscan (3.1.0)
+    unicode-display_width (2.5.0)
 
 PLATFORMS
   ruby
@@ -51,7 +57,7 @@ DEPENDENCIES
   minitest-reporters
   mocha
   rake
-  rubocop (~> 1.13.0)
+  rubocop (~> 1.50.2)
   rubocop-minitest
   rubocop-performance
   rubocop-rake