Should `use_tz` adjust the input time?

Prework

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Description

I was expecting that use_tz would translate the input time into the timezone provided to use_tz, but it seems to not be having an effect.

Reproducible example

dt <- withr::with_timezone("UTC", Sys.time())
attr(dt, "tzone") <- "UTC"

strftime(dt, "%F %T", tz = "UTC")
#> [1] "2023-03-22 13:55:52"
strftime(dt, "%F %T", tz = "America/New_York")
#> [1] "2023-03-22 09:55:52"

bigD::fdt(dt)
#> [1] "2023-03-22T13:55:52Z"
bigD::fdt(dt, use_tz = "America/New_York")
#> [1] "2023-03-22T13:55:52Z"

Expected result

I was expecting the output of fdt() to use the America/New_York timezone without me having to adjust the input time object.

attr(dt, "tzone") <- "America/New_York"
bigD::fdt(dt)
#> [1] "2023-03-22T09:55:52-04:00"

Session info

``` r sessioninfo::session_info() #> ─ Session info ─────────────────────────────────────────────────────────────── #> setting value #> version R version 4.2.2 (2022-10-31) #> os macOS Big Sur ... 10.16 #> system x86_64, darwin17.0 #> ui X11 #> language (EN) #> collate en_US.UTF-8 #> ctype en_US.UTF-8 #> tz America/New_York #> date 2023-03-22 #> pandoc 2.19.2 @ /Applications/RStudio.app/Contents/Resources/app/quarto/bin/tools/ (via rmarkdown) #> #> ─ Packages ─────────────────────────────────────────────────────────────────── #> package * version date (UTC) lib source #> bigD 0.2.0.9000 2023-03-22 [1] Github (rstudio/bigd@8fba5c6) #> cli 3.6.0 2023-01-09 [1] CRAN (R 4.2.0) #> digest 0.6.31 2022-12-11 [1] CRAN (R 4.2.0) #> evaluate 0.19 2022-12-13 [1] CRAN (R 4.2.0) #> fansi 1.0.3 2022-03-24 [1] CRAN (R 4.2.0) #> fastmap 1.1.0 2021-01-25 [1] CRAN (R 4.2.0) #> fs 1.5.2 2021-12-08 [1] CRAN (R 4.2.0) #> glue 1.6.2 2022-02-24 [1] CRAN (R 4.2.0) #> htmltools 0.5.4 2022-12-07 [1] CRAN (R 4.2.0) #> knitr 1.42 2023-01-25 [1] CRAN (R 4.2.0) #> lifecycle 1.0.3 2022-10-07 [1] CRAN (R 4.2.0) #> magrittr 2.0.3 2022-03-30 [1] CRAN (R 4.2.0) #> pillar 1.8.1 2022-08-19 [1] CRAN (R 4.2.1) #> pkgconfig 2.0.3 2019-09-22 [1] CRAN (R 4.2.0) #> purrr 1.0.1 2023-01-10 [1] CRAN (R 4.2.0) #> R.cache 0.15.0 2021-04-30 [1] CRAN (R 4.2.0) #> R.methodsS3 1.8.1 2020-08-26 [1] CRAN (R 4.2.0) #> R.oo 1.24.0 2020-08-26 [1] CRAN (R 4.2.0) #> R.utils 2.11.0 2021-09-26 [1] CRAN (R 4.2.0) #> reprex 2.0.2 2022-08-17 [1] CRAN (R 4.2.0) #> rlang 1.0.6 2022-09-24 [1] CRAN (R 4.2.0) #> rmarkdown 2.20 2023-01-19 [1] CRAN (R 4.2.0) #> rstudioapi 0.14 2022-08-22 [1] CRAN (R 4.2.0) #> sessioninfo 1.2.2 2021-12-06 [1] CRAN (R 4.2.0) #> styler 1.7.0 2022-03-13 [1] CRAN (R 4.2.0) #> tibble 3.1.8 2022-07-22 [1] CRAN (R 4.2.0) #> utf8 1.2.2 2021-07-24 [1] CRAN (R 4.2.0) #> vctrs 0.5.1 2022-11-16 [1] CRAN (R 4.2.0) #> withr 2.5.0 2022-03-03 [1] CRAN (R 4.2.0) #> xfun 0.36 2022-12-21 [1] CRAN (R 4.2.0) #> yaml 2.3.6 2022-10-18 [1] CRAN (R 4.2.0) #> #> [1] /Users/garrick/Library/R/x86_64/4.2/library #> [2] /Library/Frameworks/R.framework/Versions/4.2/Resources/library #> #> ────────────────────────────────────────────────────────────────────────────── ```

rstudio / bigD