1 files changed, 4 insertions, 1 deletions
diff --git a/Library/Homebrew/resource.rb b/Library/Homebrew/resource.rb
index f6b417fc5..573a7bcb1 100644
--- a/Library/Homebrew/resource.rb
+++ b/Library/Homebrew/resource.rb
@@ -72,8 +72,11 @@ class Resource
     downloader.clear_cache
   end
 
-  # Fetch, verify, and unpack the resource
   def stage(target=nil, &block)
+    unless target || block
+      raise ArgumentError, "target directory or block is required"
+    end
+
     verify_download_integrity(fetch)
     unpack(target, &block)
   end