wrong return type in `ceiling_date` when unit = "week"

[shrektan]

Hi, @vspinu, I tried the CRAN version of lubridate and found a bug related to ceiling_date when the unit = "week". It should return a date object instead of a datetime.

Here's the reproducible example:

library(lubridate)

# ceiling date returns a time
ceiling_date(ymd("20160927"), "week")
## [1] "2016-10-02 08:00:00 CST"

# while the floor_date returns a date
floor_date(ymd("20160927"), "week")
## [1] "2016-09-25"

[shrektan]

I've filed a PR.

[vspinu]

It should return a date object instead of a datetime.

Why do you think so?

If it returns date for week, shouldn't it return date for "day", "month" and "year" as well?

[shrektan]

It's true that day month and year returns a date. Isn't it?

[shrektan]

@vspinu Here's is what's returned in lubridate version 1.6.0. As you can see, only unit = "week" behaves differently.

ceiling_date(ymd("20160927"), "year")
## [1] "2017-01-01"
ceiling_date(ymd("20160927"), "month")
## [1] "2016-10-01"
ceiling_date(ymd("20160927"), "week")
## [1] "2016-10-02 08:00:00 CST"
ceiling_date(ymd("20160927"), "day")
## [1] "2016-09-28"

[vspinu]

Yes. You are right. I got confused for a second due to recent re-designing of rounding API.

[shrektan]

It's a very powerful and useful package. Certainly it takes lots of effort to improve. 🍺

[Henrik-P]

Seems like this issue is alive again in lubridate_1.6.0:

ceiling_date(ymd("20160927"), "year")
# [1] "2017-01-01"

ceiling_date(ymd("20160927"), "month")
# [1] "2016-10-01"

ceiling_date(ymd("20160927"), "week")
# [1] "2016-10-02 02:00:00 CEST"

ceiling_date(ymd("20160927"), "day")
# [1] "2016-09-28"

[cderv]

It is ok in current development version of lubridate 1.6.0.9009.

library(lubridate)
ceiling_date(ymd("20160927"), "year")
#> [1] "2017-01-01"
ceiling_date(ymd("20160927"), "month")
#> [1] "2016-10-01"
ceiling_date(ymd("20160927"), "week")
#> [1] "2016-10-02"
ceiling_date(ymd("20160927"), "day")
#> [1] "2016-09-28"