[R-pkg-devel] Surprised by as.Date() and lubridate::today()

[Pedro J. Aphalo]

Hello,

I was surprised first by the behaviour of lubridate::today(), and when I 
investigated further, by the behaviour of as.Date.POSIXlt(). Some 
examples follow:

library(lubridate)
# today() does not behave as I expected
tz(now(tzone = "EET"))
tz(today(tzone = "EET")) # UTC!!
today("America/New_York") == today("Asia/Tokyo") # FALSE with no warning 
(lack of warning is wrong?).
tz(today("America/New_York")) # UTC!
tz(today("Asia/Tokyo")) # UTC!
ymd("2017-06-19", tz = "America/New_York") == ymd("2017-06-20", tz = 
"Asia/Tokyo") # FALSE with warning.
tz(ymd("2017-06-19", tz = "America/New_York")) # OK
tz(ymd("2017-06-20", tz = "Asia/Tokyo")) # OK

# nothing unusual here
tz(as.POSIXlt(now(), tz = "EET"))
tz(as.POSIXlt(now(tzone = "EET")))
tz(as.POSIXlt(now(tzone = "EET"), tz = "EET"))
# but the unexpected seems to be the behaviour of as.Date.POSIXlt() as 
all returned values have tz set to "UTC"
tz(as.Date(as.POSIXlt(now())))  # UTC!!
tz(as.Date(as.POSIXlt(now(tzone = "EET"), tz = "EET"), tz = "EET"))  # UTC!!
tz(as.Date(as.POSIXlt(now(), tz = "EET"), tz = "EET"))  # UTC!!
tz(as.Date(as.POSIXlt(now()), tz = "EET"))  # UTC!!

Is this as expected? (R 3.4.0 Windows 10 64, and R 3.3.3, with lubridate 
1.6.0)

Thanks in advance for any insight.

Best regards,

Pedro.

-- 
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Pedro J. Aphalo
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