input_ae <- tibble::tribble(
  ~STUDYID,   ~USUBJID,   ~AESEQ, ~AESTDTC,
  "my_study", "subject1", 1,      "2020-01-02",
  "my_study", "subject1", 2,      "2020-08-31",
  "my_study", "subject1", 3,      "2020-10-10",
  "my_study", "subject2", 1,      "2019-05-15",
  "my_study", "subject2", 2,      "2020-02-20",
  "my_study", "subject3", 1,      "2020-03-02",
  "my_study", "subject4", 1,      "2020-11-02"
) %>%
  mutate(
    AESTDT = ymd(AESTDTC)
  )

input_ex <- tibble::tribble(
  ~STUDYID, ~USUBJID, ~EXSTDTC, ~EXENDTC, ~EXSEQ, ~EXDOSE, ~EXTRT,
  "my_study", "subject1", "2020-01-01", "2020-01-01", 1, 10, "treatment",
  "my_study", "subject1", "2020-08-29", "2020-08-29", 2, 10, "treatment",
  "my_study", "subject1", "2020-09-02", "2020-09-02", 3, 10, "treatment",
  "my_study", "subject1", "2020-10-20", "2020-10-20", 4, 10, "treatment",
  "my_study", "subject2", "2019-05-25", "2019-05-25", 1, 0, "placebo",
  "my_study", "subject2", "2020-01-20", "2020-01-20", 2, 0, "placebo",
  "my_study", "subject3", "2020-03-15", "2020-03-15", 1, 10, "treatment"
) %>%
  mutate(
    EXSTDT = as.Date(EXSTDTC),
    EXENDT = as.Date(EXENDTC)
  )

# derive_var_last_dose_amt ----
## Test 1: works as expected and returns an error message----
test_that("derive_var_last_dose_amt Test 1: works as expected and returns an error message", {
  expected_output <- mutate(
    input_ae,
    LDOSE = c(10, 10, 10, NA, 0, NA, NA)
  )
  expect_error(
    derive_var_last_dose_amt(
      input_ae,
      input_ex,
      filter_ex = (EXDOSE > 0) | (EXDOSE == 0 & EXTRT == "placebo"),
      by_vars = exprs(STUDYID, USUBJID),
      dose_date = EXENDT,
      analysis_date = AESTDT,
      new_var = LDOSE,
      dose_var = EXDOSE,
      single_dose_condition = (EXSTDTC == EXENDTC),
      traceability_vars = NULL
    ),
    class = "lifecycle_error_deprecated"
  )
})