Add ability to parse weeks

Author: aleksanderbl29

R/dst_date_parse.R

@@ -1,7 +1,13 @@
 #' Helper function to parse the dates from the statbank.
 #'
+#' @description
+#' The weeks are returned to be the first day of the week. It does happen that
+#' the first day of week 1 is a day in december of the year before. This is
+#' intended and a weird artefact of the system we have.
+#'
+#'
 #' @param dst_date A vector of length one or more with date formats like
-#'   1982M12D09, 1982M12, 1982Q4 or 1982
+#'   1982M12D09, 2004U27, 1982M12, 1982Q4 or 1982
 #' @returns Returns the input date formatted to be Europe/Copenhagen
 #' @noRd
 dst_date_parse <- function(dst_date) {
@@ -22,6 +28,29 @@ dst_date_parse <- function(dst_date) {
       ),
       tz = tz
     )
+  } else if (
+    # nolint start
+      all(stringr::str_detect(dst_date, "^[0-9]{4}U(0[1-9]|[1-4][0-9]|5[0-2])$")) &&
+      all(stringr::str_length(string = dst_date) == 7)
+    # nolint end
+    ) {
+    # Weekly format
+    # Find year and and week
+    year <- lubridate::ymd(paste0(
+      stringr::str_sub(dst_date, start = 1L, end = 4L),
+      "-01-01"))
+
+    week <- stringr::str_sub(dst_date, start = -2L)
+
+    # Get the first day of the week that is 7 (days) times weeks minus one to
+    # account for weird date-numbers. Also ensure the week starts on a monday
+    dst_date <- lubridate::floor_date(
+      year + lubridate::days(7 * (as.numeric(week) - 1)),
+      unit = "week",
+      week_start = 1
+    )
+
+    dst_date <- lubridate::ymd(dst_date, tz = tz)
   } else if (
     # nolint start
     all(stringr::str_detect(

tests/testthat/test-dst_date_parse.R

@@ -6,6 +6,10 @@ test_that("dst_date_parse gives the correct class.", {
   expect_equal(class(dst_date_parse(dst_date = "2000M01D01")), exp_dates)
   expect_equal(class(dst_date_parse(dst_date = c("2000M01D20", "2000M02D21", "2000M03D23", "2000M04D24"))), exp_dates)
 
+  # Weekly
+  expect_equal(class(dst_date_parse(dst_date = "2000U01")), exp_dates)
+  expect_equal(class(dst_date_parse(dst_date = c("2000U01", "2000U03", "2023U47", "2005U11"))), exp_dates)
+
   # Monthly
   expect_equal(class(dst_date_parse(dst_date = "2000M01")), exp_dates)
   expect_equal(class(dst_date_parse(dst_date = c("2000M01", "2000M02", "2000M03", "2000M04", "2000M10", "2000M11"))), exp_dates)
@@ -33,6 +37,10 @@ test_that("Test that dst_date_parse stops when the input is bad.", {
   expect_error(dst_date_parse(dst_date = "2000M01D35"))
   expect_error(dst_date_parse(dst_date = "2000M10D40"))
 
+  # Daily
+  expect_error(dst_date_parse(dst_date = "2000U57"))
+  expect_error(dst_date_parse(dst_date = "20000U40"))
+
   # Monthly
   expect_error(dst_date_parse(dst_date = "20000M01"))
   expect_error(dst_date_parse(dst_date = "2000M101"))