Implement date_now() and date_today() (#210)

Author: DavisVaughan

NAMESPACE

@@ -563,6 +563,7 @@ export(date_format)
 export(date_group)
 export(date_leap_year)
 export(date_month_factor)
+export(date_now)
 export(date_parse)
 export(date_round)
 export(date_set_zone)
@@ -571,6 +572,7 @@ export(date_time_build)
 export(date_time_parse)
 export(date_time_parse_abbrev)
 export(date_time_parse_complete)
+export(date_today)
 export(date_weekday_factor)
 export(date_zone)
 export(duration_cast)

NEWS.md

@@ -27,6 +27,12 @@
     a direct conversion impossible, `nonexistent` and `ambiguous` can be used
     to resolve any issues.
 
+* Added two new convenient helpers (#197):
+
+  * `date_today()` for getting the current date (Date)
+  
+  * `date_now()` for getting the current date-time (POSIXct)
+
 * Fixed a bug where converting from a time point to a Date or POSIXct could
   round incorrectly (#205).
 

R/date.R

@@ -1086,3 +1086,45 @@ date_build <- function(year, month = 1L, day = 1L, ..., invalid = NULL) {
   x <- invalid_resolve(x, invalid = invalid)
   as.Date(x)
 }
+
+# ------------------------------------------------------------------------------
+
+#' Current date and date-time
+#'
+#' @description
+#' - `date_today()` returns the current date in the specified `zone` as a Date.
+#'
+#' - `date_now()` returns the current date-time in the specified `zone` as a
+#' POSIXct.
+#'
+#' @details
+#' clock assumes that Date is a _naive_ type, like naive-time. This means that
+#' `date_today()` first looks up the current date-time in the specified `zone`,
+#' then converts that to a Date, retaining the printed time while dropping any
+#' information about that time zone.
+#'
+#' @inheritParams zoned_time_now
+#'
+#' @return
+#' - `date_today()` a single Date.
+#'
+#' - `date_now()` a single POSIXct.
+#'
+#' @name date-today
+#'
+#' @examples
+#' # Current date in the local time zone
+#' date_today("")
+#'
+#' # Current date in a specified time zone
+#' date_today("Europe/London")
+#'
+#' # Current date-time in that same time zone
+#' date_now("Europe/London")
+NULL
+
+#' @rdname date-today
+#' @export
+date_today <- function(zone) {
+  as.Date(zoned_time_now(zone))
+}

R/posixt.R

@@ -1276,3 +1276,11 @@ date_time_build <- function(year,
   x <- invalid_resolve(x, invalid = invalid)
   as.POSIXct(x, tz = zone, nonexistent = nonexistent, ambiguous = ambiguous)
 }
+
+# ------------------------------------------------------------------------------
+
+#' @rdname date-today
+#' @export
+date_now <- function(zone) {
+  as.POSIXct(zoned_time_now(zone))
+}

_pkgdown.yml

@@ -13,6 +13,7 @@ reference:
   contents:
   - date_build
   - date_time_build
+  - date-today
   - date_group
   - date-and-date-time-rounding
   - date-and-date-time-shifting

man/date-today.Rd

@@ -311,6 +311,15 @@ test_that("can handle invalid dates", {
   )
 })
 
+# ------------------------------------------------------------------------------
+# date_today()
+
+test_that("can get the current date", {
+  x <- date_today("America/New_York")
+  expect_length(x, 1)
+  expect_s3_class(x, "Date")
+})
+
 # ------------------------------------------------------------------------------
 # date_zone()
 

tests/testthat/test-date.R

@@ -389,6 +389,15 @@ test_that("can handle ambiguous times", {
   )
 })
 
+# ------------------------------------------------------------------------------
+# date_now()
+
+test_that("can get the current date-time", {
+  x <- date_now("America/New_York")
+  expect_length(x, 1)
+  expect_s3_class(x, "POSIXct")
+})
+
 # ------------------------------------------------------------------------------
 # vec_arith()