tests/testthat/test-date2week.R

In aweek: Convert Dates to Arbitrary Week Definitions

context("conversion to aweek tests")


dats <- sprintf("%d-01-01", 2001:2019)


dats <- as.Date(c(dats, NA_character_))

test_that("an error is thrown if something can't be converted to a date", {
                
  expect_error(date2week(iris), "iris could not be converted to a date")                
                
})

# test_that("an error will be thrown if a date is NULL", {

#   expect_error(date2week(NULL), "NULL could not be converted to a date.")

# })

test_that("an error will be thrown if the user tries to use factor without floor_day", {

  expect_error(date2week(dats[1], factor = TRUE, floor_day = FALSE), 
               "as of aweek 1.0, using factor without floor_day is not allowed.")
})


test_that("January first dates can be properly converted", {

  # ISO week
  datw    <- date2week(dats, 1)
  # Epi week
  datew   <- date2week(dats, 7, numeric = TRUE)
  # Floored
  datf    <- date2week(dats, 1, floor_day = TRUE)
  # Factors
  datffac <- date2week(dats, 1, floor_day = TRUE, factor = TRUE)

  datn    <- date2week(dats, 1, numeric = TRUE)

  datback <- as.Date(datw)
  # isoweeks
  weeknums <- c(1, 1, 1, 1, 53, 52, 1, 1, 1, 53, 52, 52, 1, 1, 1, 53, 52, 1, 1, NA) 
  # epiweeks
  epiweeks <- c(1, 1, 1, 53, 52, 1, 1, 1, 53, 52, 52, 1, 1, 1, 53, 52, 1, 1, 1, NA) 
  iw       <- c("2001-W01-1", "2002-W01-2", "2003-W01-3", "2004-W01-4",
                "2004-W53-6", "2005-W52-7", "2007-W01-1", "2008-W01-2",
                "2009-W01-4", "2009-W53-5", "2010-W52-6", "2011-W52-7",
                "2013-W01-2", "2014-W01-3", "2015-W01-4", "2015-W53-5",
                "2016-W52-7", "2018-W01-1", "2019-W01-2", NA)
  class(iw) <- "aweek"
  attr(iw, "week_start") <- 1L
  floored <- gsub("-\\d$", "", iw)

  # conversions are reversible
  expect_identical(as.character(dats), as.character(datback))

  # weeks print as expected
  expect_identical(datw, iw)

  # wee numbers display as expected
  expect_identical(datn, weeknums)

  expect_identical(datew, epiweeks)

  # floored weeks are handled as expected
  expect_identical(datf, floored)

  expect_identical(trunc(datw), floored)

  # Factors are handled as expected
  expect_identical(as.character(datffac), as.character(datf))

  # Factor levels are the sequence of dates
  expect_identical(seq.Date(min(dats, na.rm = TRUE), max(dats, na.rm = TRUE), by = 7), 
                   week2date(levels(datffac), 1))

})

test_that("dates can be co back and forth no matter the start day", {


  for (i in 1:7) {
    datw    <- date2week(dats, i)
    datback <- week2date(datw)

    expect_identical(as.character(dats), as.character(datback), 
                     info = sprintf("day: %d", i))
  }

})

test_that("invalid weekdays throw an error", {
  
  expect_error(week2date("2019-W20-8"), "Weekdays must be between 1 and 7")
  expect_error(date2week(Sys.Date(), week_start = 1:7), "week_start must be length 1")
  expect_error(date2week(Sys.Date(), week_start = 8), "Weekdays must be between 1 and 7")

})