Turn lookup context in to a stack, push and pop if formats change

This commit keeps a stack of lookup contexts on the ActionView::Base
instance.  If a format is passed to render, we instantiate a new lookup
context and push it on the stack, that way any child calls to "render"
will use the same format information as the parent.  This also isolates
"sibling" calls to render (multiple calls to render in the same
template).

Fixes #35222 #34138

2 files changed, 6 insertions, 4 deletions

diff --git a/actionview/test/template/log_subscriber_test.rb b/actionview/test/template/log_subscriber_test.rb
index 83bb651ea3..85735139c1 100644
--- a/actionview/test/template/log_subscriber_test.rb
+++ b/actionview/test/template/log_subscriber_test.rb
@@ -16,8 +16,7 @@ class AVLogSubscriberTest < ActiveSupport::TestCase
     view_paths = ActionController::Base.view_paths
 
     lookup_context = ActionView::LookupContext.new(view_paths, {}, ["test"])
-    renderer       = ActionView::Renderer.new(lookup_context)
-    @view          = ActionView::Base.with_empty_template_cache.new(renderer, {})
+    @view          = ActionView::Base.with_empty_template_cache.new(lookup_context, {})
 
     ActionView::LogSubscriber.attach_to :action_view
 
diff --git a/actionview/test/template/render_test.rb b/actionview/test/template/render_test.rb
index e36babfd25..88047fd920 100644
--- a/actionview/test/template/render_test.rb
+++ b/actionview/test/template/render_test.rb
@@ -20,7 +20,10 @@ module RenderTestCases
 
     controller = TestController.new
 
-    @controller_view = controller.view_context_class.with_empty_template_cache.new(controller.view_renderer, controller.view_assigns, controller)
+    @controller_view = controller.view_context_class.with_empty_template_cache.new(
+      controller.lookup_context,
+      controller.view_assigns,
+      controller)
 
     # Reload and register danish language for testing
     I18n.backend.store_translations "da", {}
@@ -83,7 +86,7 @@ module RenderTestCases
 
   def test_render_partial_use_last_prepended_format_for_partials_with_the_same_names
     @view.lookup_context.formats = [:html]
-    assert_equal "\nHTML Template, but JSON partial", @view.render(template: "test/change_priority")
+    assert_equal "\nHTML Template, but HTML partial", @view.render(template: "test/change_priority")
   end
 
   def test_render_template_with_a_missing_partial_of_another_format