1 files changed, 13 insertions, 4 deletions
diff --git a/ext/digest/lib/sha1.rb b/ext/digest/lib/sha1.rb
index c4ac6f66ea..4446e12e8d 100644
--- a/ext/digest/lib/sha1.rb
+++ b/ext/digest/lib/sha1.rb
@@ -5,10 +5,19 @@
 
 require 'digest/sha1'
 
-SHA1 = Digest::SHA1
+class SHA1 < Digest::SHA1
+  class << self
+    alias orig_new new
+    def new(str = nil)
+      if str
+        orig_new.update(str)
+      else
+        orig_new
+      end
+    end
 
-class SHA1
-  def self.sha1(*args)
-    new(*args)
+    def sha1(*args)
+      new(*args)
+    end
   end
 end