Date coercion

NAMESPACE

@@ -97,6 +97,7 @@ export(as.difftime)
 export(as.duration)
 export(as.interval)
 export(as.period)
+export(as_date)
 export(ceiling_date)
 export(date)
 export(date_decimal)
@@ -267,6 +268,7 @@ exportMethods(as.character)
 exportMethods(as.difftime)
 exportMethods(as.interval)
 exportMethods(as.numeric)
+exportMethods(as_date)
 exportMethods(c)
 exportMethods(intersect)
 exportMethods(reclass_timespan)

NEWS.md

@@ -7,6 +7,10 @@ Version 1.5.0.9000 (development)
 * [#373](https://github.com/hadley/lubridate/issues/373) New `date` and `date<-` additions to the `year`, `month` etc family of accessors. 
 * [#365](https://github.com/hadley/lubridate/issues/365) New very fast datetime constructor `make_datetime` (dropin replacement of `ISOdatetime`).
 * [#344](https://github.com/hadley/lubridate/issues/344) `force_tz` and `with_tz` can handle data.frames component-wise
+* [#355](https://github.com/hadley/lubridate/issues/355) `as_date` methods with 
+sensible defaults including POSIXt objects being converted to Date objects by 
+effectively ignoring sub-day time units in the time-zone of the POSIXt object.
+
 
 ### CHANGES
 

tests/testthat/test-Dates.R

@@ -4,17 +4,28 @@ test_that("is.Date works as expected",{
   expect_that(is.Date(234), is_false())
   expect_that(is.Date(as.POSIXct("2008-08-03 13:01:59", tz = "UTC")),
     is_false())
-  expect_that(is.Date(as.POSIXlt("2008-08-03 13:01:59", tz = "UTC")), 
+  expect_that(is.Date(as.POSIXlt("2008-08-03 13:01:59", tz = "UTC")),
     is_false())
   expect_that(is.Date(Sys.Date()), is_true())
   expect_that(is.Date(minutes(1)), is_false())
   expect_that(is.Date(dminutes(1)), is_false())
   expect_that(is.Date(interval(
-    as.POSIXct("2008-08-03 13:01:59", tz = "UTC"), 
+    as.POSIXct("2008-08-03 13:01:59", tz = "UTC"),
     as.POSIXct("2009-08-03 13:01:59", tz = "UTC") )), is_false())
 })
 
 test_that("is.Date handles vectors",{
   expect_that(is.Date(c(Sys.Date(), as.Date("2009-10-31"))),
     is_true())
 })
+
+test_that("as_date works", {
+  dt1 <- as.POSIXct("2010-08-03 00:59:59.23")
+  dt2 <- as.POSIXct("2010-08-03 00:59:59.23", tz="Europe/London")
+  dt3 <- as.POSIXct("2010-11-03 00:59:59.23")
+  dt4 <- as.POSIXct("2010-11-03 00:59:59.23", tz="Europe/London")
+  expect_equal(as_date(dt1), as.Date("2010-08-03"))
+  expect_equal(as_date(dt2), as.Date("2010-08-03"))
+  expect_equal(as_date(dt3), as.Date("2010-11-03"))
+  expect_equal(as_date(dt4), as.Date("2010-11-03"))
+})