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https://issues.apache.org/jira/browse/ARROW-14124?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Neal Richardson resolved ARROW-14124.
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Fix Version/s: 6.0.0
Resolution: Fixed
Issue resolved by pull request 11250
[https://github.com/apache/arrow/pull/11250]
> [R] Timezone support in R <= 3.4
> --------------------------------
>
> Key: ARROW-14124
> URL: https://issues.apache.org/jira/browse/ARROW-14124
> Project: Apache Arrow
> Issue Type: Bug
> Components: R
> Reporter: Jonathan Keane
> Assignee: Jonathan Keane
> Priority: Major
> Labels: pull-request-available
> Fix For: 6.0.0
>
> Time Spent: 1h
> Remaining Estimate: 0h
>
> The error is:
> https://github.com/ursacomputing/crossbow/runs/3696604088#step:7:15209
> {code}
> Timezone not present, cannot convert to string with timezone: %Y-%m-%d%z
> {code}
> Ok, I think I’ve got close to the source of the issue (though let me tell you
> neither the source nor the docs for R are accurate [1] on this…)
> 3.4 (and earlier):
> {code:r}
> > attributes(c(lubridate::ymd_hms("2018-10-07 19:04:05", tz = "Etc/GMT+6"),
> > NA))
> $class
> [1] "POSIXct" "POSIXt"
> {code}
> 3.5 (and later):
> {code:r}
> > attributes(c(lubridate::ymd_hms("2018-10-07 19:04:05", tz = "Etc/GMT+6"),
> > NA))
> $class
> [1] "POSIXct" "POSIXt"
> $tzone
> [1] "Etc/GMT+6"
> {code}
> So R itself is dropping the {{tzone}} attribute when we use {{c()}}, that is
> being passed to Arrow as such, and then when Arrow goes to print a timezone
> it (rightfully!) complains that there is no timezone to be formatted into the
> string.
> This behavior actually sounds right (given the inputs), so I propose that we
> catch the error R <=3.4 (or skip the test in r<=3.4)
> [1] - The documented behavior is current, but it didn't change at the same
> time as the actual behavior.
> The docs starting in 4.1.0 state:
> Using \code{\link{c}} on \code{"POSIXlt"} objects converts them to the
> current time zone, and on \code{"POSIXct"} objects drops any
> \code{"tzone"} attributes, unless they are all marked with the same
> time zone.
> https://github.com/wch/r-source/blob/tags/R-4-1-0/src/library/base/man/DateTimeClasses.Rd#L180-L183
> The docs before that state:
> Using \code{\link{c}} on \code{"POSIXlt"} objects converts them to the
> current time zone, and on \code{"POSIXct"} objects drops any
> \code{"tzone"} attributes (even if they are all marked with the same
> time zone).
> https://github.com/wch/r-source/blob/tags/R-4-0-5/src/library/base/man/DateTimeClasses.Rd
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