ARROW-14442: [R] fix behaviour when converting timestamps with "" as …

…tzone Closes apache#12240 from dragosmg/timestampts_missing_timezone Authored-by: Dragoș Moldovan-Grünfeld <[email protected]> Signed-off-by: Jonathan Keane <[email protected]>
rafael-telles · Apr 19, 2022 · 7889c0c · 7889c0c
1 parent 9c86a9e
commit 7889c0c
Show file tree

Hide file tree

Showing 3 changed files with 28 additions and 9 deletions.
diff --git a/r/src/type_infer.cpp b/r/src/type_infer.cpp
@@ -72,7 +72,8 @@ std::shared_ptr<arrow::DataType> InferArrowTypeFromVector<INTSXP>(SEXP x) {
   } else if (Rf_inherits(x, "POSIXct")) {
     auto tzone_sexp = Rf_getAttrib(x, symbols::tzone);
     if (Rf_isNull(tzone_sexp)) {
-      return timestamp(TimeUnit::MICRO);
+      auto systzone_sexp = cpp11::package("base")["Sys.timezone"];
+      return timestamp(TimeUnit::MICRO, CHAR(STRING_ELT(systzone_sexp(), 0)));
     } else {
       return timestamp(TimeUnit::MICRO, CHAR(STRING_ELT(tzone_sexp, 0)));
     }
@@ -88,7 +89,8 @@ std::shared_ptr<arrow::DataType> InferArrowTypeFromVector<REALSXP>(SEXP x) {
   if (Rf_inherits(x, "POSIXct")) {
     auto tzone_sexp = Rf_getAttrib(x, symbols::tzone);
     if (Rf_isNull(tzone_sexp)) {
-      return timestamp(TimeUnit::MICRO);
+      auto systzone_sexp = cpp11::package("base")["Sys.timezone"];
+      return timestamp(TimeUnit::MICRO, CHAR(STRING_ELT(systzone_sexp(), 0)));
     } else {
       return timestamp(TimeUnit::MICRO, CHAR(STRING_ELT(tzone_sexp, 0)));
     }

diff --git a/r/tests/testthat/test-Array.R b/r/tests/testthat/test-Array.R
@@ -260,18 +260,39 @@ test_that("array supports POSIXct (ARROW-3340)", {
   expect_array_roundtrip(times2, timestamp("us", "US/Eastern"))
 })
 
-test_that("array supports POSIXct without timezone", {
-  # Make sure timezone is not set
+test_that("array uses local timezone for POSIXct without timezone", {
   withr::with_envvar(c(TZ = ""), {
     times <- strptime("2019-02-03 12:34:56", format = "%Y-%m-%d %H:%M:%S") + 1:10
-    expect_array_roundtrip(times, timestamp("us", ""))
+    expect_equal(attr(times, "tzone"), NULL)
+    expect_array_roundtrip(times, timestamp("us", Sys.timezone()))
 
     # Also test the INTSXP code path
     skip("Ingest_POSIXct only implemented for REALSXP")
     times_int <- as.integer(times)
     attributes(times_int) <- attributes(times)
     expect_array_roundtrip(times_int, timestamp("us", ""))
   })
+
+  # If there is a timezone set, we record that
+  withr::with_timezone("Pacific/Marquesas", {
+    times <- strptime("2019-02-03 12:34:56", format = "%Y-%m-%d %H:%M:%S") + 1:10
+    expect_equal(attr(times, "tzone"), "Pacific/Marquesas")
+    expect_array_roundtrip(times, timestamp("us", "Pacific/Marquesas"))
+
+    times_with_tz <- strptime(
+      "2019-02-03 12:34:56",
+      format = "%Y-%m-%d %H:%M:%S",
+      tz = "Asia/Katmandu") + 1:10
+    expect_equal(attr(times, "tzone"), "Asia/Katmandu")
+    expect_array_roundtrip(times, timestamp("us", "Asia/Katmandu"))
+  })
+
+  # and although the TZ is NULL in R, we set it to the Sys.timezone()
+  withr::with_timezone(NA, {
+    times <- strptime("2019-02-03 12:34:56", format = "%Y-%m-%d %H:%M:%S") + 1:10
+    expect_equal(attr(times, "tzone"), NULL)
+    expect_array_roundtrip(times, timestamp("us", Sys.timezone()))
+  })
 })
 
 test_that("Timezone handling in Arrow roundtrip (ARROW-3543)", {

diff --git a/r/tests/testthat/test-dplyr-funcs-datetime.R b/r/tests/testthat/test-dplyr-funcs-datetime.R
@@ -693,7 +693,6 @@ test_that("extract yday from date", {
 })
 
 test_that("leap_year mirror lubridate", {
-
   compare_dplyr_binding(
     .input %>%
       mutate(x = leap_year(date)) %>%
@@ -721,7 +720,6 @@ test_that("leap_year mirror lubridate", {
       ))
     )
   )
-
 })
 
 test_that("am/pm mirror lubridate", {
@@ -741,10 +739,8 @@ test_that("am/pm mirror lubridate", {
         ),
         format = "%Y-%m-%d %H:%M:%S"
       )
-
     )
   )
-
 })
 
 test_that("extract tz", {