diff --git a/lib/gitlab/git.rb b/lib/gitlab/git.rb
index f065cc5e9e9962c70407370403881452dab5c795..a33daeb119f72ab0c2d0927bbd37f017ac3a27eb 100644
--- a/lib/gitlab/git.rb
+++ b/lib/gitlab/git.rb
@@ -1,8 +1,9 @@
 module Gitlab
   module Git
-    BLANK_SHA = '0' * 40
-    TAG_REF_PREFIX = "refs/tags/"
-    BRANCH_REF_PREFIX = "refs/heads/"
+    # '0' * 40 -- this was easyer to freeze
+    BLANK_SHA = "0000000000000000000000000000000000000000".freeze
+    TAG_REF_PREFIX = "refs/tags/".freeze
+    BRANCH_REF_PREFIX = "refs/heads/".freeze
 
     class << self
       def ref_name(ref)
diff --git a/spec/lib/gitlab/git_spec.rb b/spec/lib/gitlab/git_spec.rb
new file mode 100644
index 0000000000000000000000000000000000000000..3b4052fa5492156c691eb3cb5d83fc7fa347932d
--- /dev/null
+++ b/spec/lib/gitlab/git_spec.rb
@@ -0,0 +1,9 @@
+require 'spec_helper'
+
+describe Gitlab::Git do
+  describe "BLANK_SHA" do
+    it "is a string of 40 zero's" do
+      expect(Gitlab::Git::BLANK_SHA).to eq('0' * 40)
+    end
+  end
+end