Fixes #23964

  - Adds #each_chunk to ActionDispatch::Response. it's a method which
    will be called by ActionDispatch::Response#each.
  - Make Response#each a proper method instead of delegating to @stream
  - In Live, instead of overriding #each, override #each_chunk.
  - `#each` should just spit out @str_body if it's already set
  - Adds #test_set_header_after_read_body_during_action
    to prove this fixes #23964
  - Adds #test_each_isnt_called_if_str_body_is_written to
    ensure #each_chunk is not called when @str_body is available
  - Call `@response.sent!` in AC::TestCase's #perform so a test response
    acts a bit more like a real response. Makes test that call  `#assert_stream_closed`
    pass again.
  - Additionally assert `#committed?` in `#assert_stream_closed`
  - Make test that was calling @response.stream.each pass again by
    calling @response.each instead.

1 files changed, 2 insertions, 1 deletions

diff --git a/actionpack/test/controller/live_stream_test.rb b/actionpack/test/controller/live_stream_test.rb
index 0c3884cd38..298e12722b 100644
--- a/actionpack/test/controller/live_stream_test.rb
+++ b/actionpack/test/controller/live_stream_test.rb
@@ -246,7 +246,8 @@ module ActionController
 
     def assert_stream_closed
       assert response.stream.closed?, 'stream should be closed'
-      assert response.sent?, 'stream should be sent'
+      assert response.committed?,     'response should be committed'
+      assert response.sent?,          'response should be sent'
     end
 
     def capture_log_output