jorisvandenbossche commented on a change in pull request #10176: URL: https://github.com/apache/arrow/pull/10176#discussion_r643921943
########## File path: cpp/src/arrow/compute/kernels/scalar_temporal_test.cc ########## @@ -0,0 +1,107 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License. + +#include <gtest/gtest.h> +#include "arrow/compute/api_scalar.h" +#include "arrow/compute/kernels/test_util.h" +#include "arrow/util/checked_cast.h" +#include "arrow/util/formatting.h" + +namespace arrow { + +using internal::StringFormatter; + +class ScalarTemporalTest : public ::testing::Test {}; + +namespace compute { + +TEST(ScalarTemporalTest, TestSimpleTemporalComponentExtraction) { + const char* times = + R"(["1970-01-01T00:00:59.123456789","2000-02-29T23:23:23.999999999", + "1899-01-01T00:59:20.001001001","2033-05-18T03:33:20.000000000", null])"; + auto unit = timestamp(TimeUnit::NANO); + auto timestamps = ArrayFromJSON(unit, times); + auto iso_calendar_type = + struct_({field("iso_year", int64()), field("iso_week", int64()), + field("weekday", int64())}); + + auto year = "[1970, 2000, 1899, 2033, null]"; + auto month = "[1, 2, 1, 5, null]"; + auto day = "[1, 29, 1, 18, null]"; + auto day_of_week = "[4, 2, 7, 3, null]"; + auto day_of_year = "[1, 60, 1, 138, null]"; + auto iso_year = "[1970, 2000, 1899, 2033, null]"; + auto iso_week = "[1, 9, 52, 20, null]"; + auto iso_calendar = ArrayFromJSON(iso_calendar_type, + R"([{"iso_year": 1970, "iso_week": 1, "weekday": 4}, + {"iso_year": 2000, "iso_week": 9, "weekday": 2}, + {"iso_year": 1899, "iso_week": 52, "weekday": 7}, + {"iso_year": 2033, "iso_week": 20, "weekday": 3}, null])"); + auto quarter = "[1, 1, 1, 2, null]"; + auto hour = "[0, 23, 0, 3, null]"; + auto minute = "[0, 23, 59, 33, null]"; + auto second = "[59.123456789, 23.999999999, 20.001001001, 20.0, null]"; + auto millisecond = "[123, 999, 1, 0, null]"; + auto microsecond = "[456, 999, 1, 0, null]"; + auto nanosecond = "[789, 999, 1, 0, null]"; + auto subsecond = "[123456789, 999999999, 1001001, 0, null]"; + + CheckScalarUnary("year", unit, times, int64(), year); + CheckScalarUnary("month", unit, times, int64(), month); + CheckScalarUnary("day", unit, times, int64(), day); + CheckScalarUnary("day_of_week", unit, times, int64(), day_of_week); + CheckScalarUnary("day_of_year", unit, times, int64(), day_of_year); + CheckScalarUnary("iso_year", unit, times, int64(), iso_year); + CheckScalarUnary("iso_week", unit, times, int64(), iso_week); + CheckScalarUnary("iso_calendar", timestamps, iso_calendar); + CheckScalarUnary("quarter", unit, times, int64(), quarter); + CheckScalarUnary("hour", unit, times, int64(), hour); + CheckScalarUnary("minute", unit, times, int64(), minute); + CheckScalarUnary("second", unit, times, float64(), second); + CheckScalarUnary("millisecond", unit, times, int64(), millisecond); + CheckScalarUnary("microsecond", unit, times, int64(), microsecond); + CheckScalarUnary("nanosecond", unit, times, int64(), nanosecond); + CheckScalarUnary("subsecond", unit, times, int64(), subsecond); +} + +TEST(ScalarTemporalTest, TestZonedTemporalComponentExtraction) { + std::string timezone = "Etc/UTC-2"; + const char* times = + R"(["1970-01-01T00:00:59.123456789","2000-02-29T23:23:23.999999999", + "1899-01-01T00:59:20.001001001","2033-05-18T03:33:20.000000000", null])"; + auto unit = timestamp(TimeUnit::NANO, timezone); + auto timestamps = ArrayFromJSON(unit, times); + + ASSERT_RAISES(Invalid, Year(timestamps)); + ASSERT_RAISES(Invalid, Month(timestamps)); + ASSERT_RAISES(Invalid, Day(timestamps)); + ASSERT_RAISES(Invalid, DayOfWeek(timestamps)); + ASSERT_RAISES(Invalid, DayOfYear(timestamps)); + ASSERT_RAISES(Invalid, ISOYear(timestamps)); + ASSERT_RAISES(Invalid, ISOWeek(timestamps)); + ASSERT_RAISES(Invalid, ISOCalendar(timestamps)); + ASSERT_RAISES(Invalid, Quarter(timestamps)); + ASSERT_RAISES(Invalid, Hour(timestamps)); + ASSERT_RAISES(Invalid, Minute(timestamps)); + ASSERT_RAISES(Invalid, Second(timestamps)); + ASSERT_RAISES(Invalid, Millisecond(timestamps)); + ASSERT_RAISES(Invalid, Microsecond(timestamps)); + ASSERT_RAISES(Invalid, Nanosecond(timestamps)); + ASSERT_RAISES(Invalid, Subsecond(timestamps)); Review comment: Indeed, the storage model of timezone-aware data is different compared to stdlib python, we are always storing the UTC timestamp (and not the localized timestamp). > In any case, this is mostly a documentation issue. If the timestamp value is always in UTC, then "year" and friends will return the year expressed in the UTC timezone. I don't think there is any reason to forbid the operation, just document it properly. I personally disagree with this. If you have a timezone-aware timestamp, as a user I would expect to get the result in *local*time. If I want to have the UTC version, I can easily first convert to UTC (which is a no-op). For "year" it most of the time doesn't change much (only the hours around New Year), but if I have a timestamp "2021-06-01 09:00:00+02:00" (CEST), and I ask for "hour", I expect to get 9 and not 7. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
