expect_output_file() behaves identically to expect_known_output().

expect_output_file(
  object,
  file,
  update = TRUE,
  ...,
  info = NULL,
  label = NULL,
  print = FALSE,
  width = 80
)

3rd edition

Deprecated lifecycle

expect_output_file() is deprecated in the 3rd edition; please use expect_snapshot_output() and friends instead.