1 files changed, 28 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/digest.rb b/activesupport/lib/active_support/digest.rb
new file mode 100644
index 0000000000..4dac32d420
--- /dev/null
+++ b/activesupport/lib/active_support/digest.rb
@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module ActiveSupport
+  class Digest #:nodoc:
+    class <<self
+      def hash_digest_class
+        @hash_digest_class || ::Digest::MD5
+      end
+
+      def hash_digest_class=(klass)
+        raise ArgumentError, "#{klass} is expected to implement hexdigest class method" unless klass.respond_to?(:hexdigest)
+        @hash_digest_class = klass
+      end
+
+      def hexdigest(arg)
+        new.hexdigest(arg)
+      end
+    end
+
+    def initialize(digest_class: nil)
+      @digest_class = digest_class || self.class.hash_digest_class
+    end
+
+    def hexdigest(arg)
+      @digest_class.hexdigest(arg).truncate(32)
+    end
+  end
+end