diff --git a/src/main/rb/eca.rb b/src/main/rb/eca.rb
index d39dd2967bc8d0987b9b54cbd56ab78c20a33fd6..d5207e8d7241b407418af7a06f92d3d206ea7923 100644
--- a/src/main/rb/eca.rb
+++ b/src/main/rb/eca.rb
@@ -126,7 +126,7 @@ end
 
 ## Get all new commits for branch, relative to itself for existing branch, relative to tree for new
 diff_git_commits_raw = ''
-if (previous_head_commit =~ /\0+/) then
+if (previous_head_commit.to_s =~ /^0+$/) then
   ## This isn't perfect as its relative to fork, but should be huge improvement
   diff_git_commits_raw = `git rev-list #{new_head_commit}  --not --branches=*`
 else