readr::write_csv(tibble::tibble(x1 = 1, x2 = 1), "a.csv")
readr::write_csv(tibble::tibble(x1 = 1, x2 = 1), "b.csv")

targets::tar_script({
  targets::tar_option_set(format = "auto")
  library("targets")
  library("tarchetypes")
  library("readr")
  library("tibble")
  library("dplyr")
  list(
    tarchetypes::tar_files(paths, c("a.csv", "b.csv")),
    targets::tar_target(
      data,
      readr::read_csv(paths, col_types = "dd"),
      pattern = map(paths)
    ),
    targets::tar_target(
      new_data,
      {
        data |> dplyr::mutate(x3 = 3)
      }
    )
  )
})

# pipeline fails
targets::tar_make()
targets::tar_meta(fields = any_of("error"), complete_only = TRUE)$error
[1] "could not load dependency data of target new_data. no applicable method for store_read_path applied to an object of class ctar_auto, tar_store"