diff --git a/Library/Homebrew/utils/pypi.rb b/Library/Homebrew/utils/pypi.rb
index c33b8db1b8..d29582c9ad 100644
--- a/Library/Homebrew/utils/pypi.rb
+++ b/Library/Homebrew/utils/pypi.rb
@@ -86,7 +86,10 @@ module PyPI
         end
       end
 
-      return if dist.nil?
+      if dist.nil?
+        onoe "#{name} exists on PyPI but lacks a suitable source distribution"
+        return
+      end
 
       @pypi_info = [
         PyPI.normalize_python_package(json["info"]["name"]), dist["url"],