Merge pull request #17771 from agis-/issue-17373

Local vars should exist in partials for falsy `:object:` values too

actionview/CHANGELOG.md

+*   Local variable in a partial is now available even if a falsy value is
+    passed to `:object` when rendering a partial.
+
+    Fixes #17373.
+
+    *Agis Anastasopoulos*
+
 *   Add support for `:enforce_utf8` option in `form_for`.
 
     This is the same option that was added in 06388b0 to `form_tag` and allows

actionview/lib/action_view/renderer/partial_renderer.rb

@@ -366,7 +366,7 @@ def setup(context, options, block)
       partial = options[:partial]
 
       if String === partial
-        @object     = options[:object]
+        @object     = options[:object] if options.has_key?(:object)
         @collection = collection_from_options
         @path       = partial
       else
@@ -506,7 +506,7 @@ def merge_prefix_into_object_path(prefix, object_path)
 
     def retrieve_template_keys
       keys = @locals.keys
-      keys << @variable if @object || @collection
+      keys << @variable if defined?(@object) || @collection
       if @collection
         keys << @variable_counter
         keys << @variable_iteration