diff --git a/Gemfile b/Gemfile
index fe054b6..8c88ed4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,7 +1,7 @@
 source "https://rubygems.org"
 
 gem "rake", "~> 10.3.2"
-gem "minitest", "~> 5.3.5"
+gem "minitest", "~> 5.12.0"
 gem "i18n", "~> 1.8.5"
 
 gemspec
diff --git a/Gemfile.lock b/Gemfile.lock
index 1131493..00ad35c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -9,7 +9,7 @@ GEM
     concurrent-ruby (1.1.7)
     i18n (1.8.5)
       concurrent-ruby (~> 1.0)
-    minitest (5.3.5)
+    minitest (5.12.0)
     rake (10.3.2)
 
 PLATFORMS
@@ -18,7 +18,7 @@ PLATFORMS
 DEPENDENCIES
   gemoji!
   i18n (~> 1.8.5)
-  minitest (~> 5.3.5)
+  minitest (~> 5.12.0)
   rake (~> 10.3.2)
 
 BUNDLED WITH