159 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// REQUIRES: std-at-least-c++2010// UNSUPPORTED: no-filesystem, no-localization, no-tzdb11 12// XFAIL: libcpp-has-no-experimental-tzdb13// XFAIL: availability-tzdb-missing14 15// <chrono>16//17// class gps_clock;18 19// static gps_time<common_type_t<_Duration, seconds>>20// from_utc(const utc<_Duration>& __time) noexcept;21 22#include <chrono>23#include <cassert>24#include <source_location>25 26#include "test_macros.h"27#include "assert_macros.h"28#include "concat_macros.h"29 30static void test_known_values() {31 namespace cr = std::chrono;32 using namespace std::literals::chrono_literals;33 34 // [time.clock.gps.overview]/135 // The clock gps_clock measures seconds since the first Sunday of January,36 // 1980 00:00:00 UTC.37 // The first Sunday is 1980-1-6 (so January sixth)38 // ... 1980-01-06 00:00:00 GPS is equivalent to 1980-01-06 00:00:00 UTC39 40 assert(cr::gps_clock::from_utc(cr::utc_clock::from_sys(cr::sys_days{cr::January / 6 / 1980})) == cr::gps_seconds{0s});41}42 43template <class Duration>44static void test_leap_seconds(std::chrono::utc_time<Duration> utc,45 std::chrono::gps_time<Duration> expected,46 std::source_location loc = std::source_location::current()) {47 auto gps = std::chrono::gps_clock::from_utc(utc);48 TEST_REQUIRE(gps == expected,49 TEST_WRITE_CONCATENATED(loc, "\nExpected output ", expected, "\nActual output ", gps, '\n'));50}51 52// Tests set if existing database entries at the time of writing.53static void test_transitions() {54 using namespace std::literals::chrono_literals;55 namespace cr = std::chrono;56 57 // "sys" is the time of the transition to the next leap second.58 // "elapsed" is the number of leap seconds before the transition.59 auto test_transition = [](cr::sys_days sys, cr::seconds elapsed) {60 constexpr auto unix_to_gps_epoch_offset =61 cr::sys_days{cr::January / 1 / 1970} - cr::sys_days{cr::January / 6 / 1980};62 cr::gps_seconds gps{sys.time_since_epoch() + unix_to_gps_epoch_offset + elapsed};63 64 test_leap_seconds(cr::utc_clock::from_sys(sys - 1ns), gps - 1ns);65 test_leap_seconds(cr::utc_clock::from_sys(sys), gps + 1s);66 test_leap_seconds(cr::utc_clock::from_sys(sys) + 1ns, gps + 1s + 1ns);67 };68 69 // Transitions from the start of UTC.70 test_transition(cr::sys_days{cr::July / 1 / 1972}, -9s);71 test_transition(cr::sys_days{cr::January / 1 / 1973}, -8s);72 test_transition(cr::sys_days{cr::January / 1 / 1974}, -7s);73 test_transition(cr::sys_days{cr::January / 1 / 1975}, -6s);74 test_transition(cr::sys_days{cr::January / 1 / 1976}, -5s);75 test_transition(cr::sys_days{cr::January / 1 / 1977}, -4s);76 test_transition(cr::sys_days{cr::January / 1 / 1978}, -3s);77 test_transition(cr::sys_days{cr::January / 1 / 1979}, -2s);78 test_transition(cr::sys_days{cr::January / 1 / 1980}, -1s);79 test_transition(cr::sys_days{cr::July / 1 / 1981}, 0s);80 test_transition(cr::sys_days{cr::July / 1 / 1982}, 1s);81 test_transition(cr::sys_days{cr::July / 1 / 1983}, 2s);82 test_transition(cr::sys_days{cr::July / 1 / 1985}, 3s);83 test_transition(cr::sys_days{cr::January / 1 / 1988}, 4s);84 test_transition(cr::sys_days{cr::January / 1 / 1990}, 5s);85 test_transition(cr::sys_days{cr::January / 1 / 1991}, 6s);86 test_transition(cr::sys_days{cr::July / 1 / 1992}, 7s);87 test_transition(cr::sys_days{cr::July / 1 / 1993}, 8s);88 test_transition(cr::sys_days{cr::July / 1 / 1994}, 9s);89 test_transition(cr::sys_days{cr::January / 1 / 1996}, 10s);90 test_transition(cr::sys_days{cr::July / 1 / 1997}, 11s);91 test_transition(cr::sys_days{cr::January / 1 / 1999}, 12s);92 test_transition(cr::sys_days{cr::January / 1 / 2006}, 13s);93 test_transition(cr::sys_days{cr::January / 1 / 2009}, 14s);94 test_transition(cr::sys_days{cr::July / 1 / 2012}, 15s);95 test_transition(cr::sys_days{cr::July / 1 / 2015}, 16s);96 test_transition(cr::sys_days{cr::January / 1 / 2017}, 17s);97}98 99// Tests whether the return type is the expected type.100static void test_return_type() {101 using namespace std::literals::chrono_literals;102 namespace cr = std::chrono;103 104 {105 [[maybe_unused]] std::same_as<cr::gps_time<cr::nanoseconds>> decltype(auto) _ =106 cr::gps_clock::from_utc(cr::utc_time<cr::nanoseconds>{0ns});107 }108 {109 [[maybe_unused]] std::same_as<cr::gps_time<cr::microseconds>> decltype(auto) _ =110 cr::gps_clock::from_utc(cr::utc_time<cr::microseconds>{0us});111 }112 {113 [[maybe_unused]] std::same_as<cr::gps_time<cr::milliseconds>> decltype(auto) _ =114 cr::gps_clock::from_utc(cr::utc_time<cr::milliseconds>{0ms});115 }116 117 {118 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =119 cr::gps_clock::from_utc(cr::utc_time<cr::seconds>{cr::seconds{0}});120 }121 122 {123 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =124 cr::gps_clock::from_utc(cr::utc_time<cr::minutes>{cr::minutes{0}});125 }126 {127 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =128 cr::gps_clock::from_utc(cr::utc_time<cr::hours>{cr::hours{0}});129 }130 {131 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =132 cr::gps_clock::from_utc(cr::utc_time<cr::days>{cr::days{0}});133 }134 {135 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =136 cr::gps_clock::from_utc(cr::utc_time<cr::weeks>{cr::weeks{0}});137 }138 {139 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =140 cr::gps_clock::from_utc(cr::utc_time<cr::months>{cr::months{0}});141 }142 {143 [[maybe_unused]] std::same_as<cr::gps_time<cr::seconds>> decltype(auto) _ =144 cr::gps_clock::from_utc(cr::utc_time<cr::years>{cr::years{0}});145 }146}147 148int main(int, const char**) {149 using namespace std::literals::chrono_literals;150 std::chrono::utc_seconds time = std::chrono::utc_seconds{0s};151 static_assert(noexcept(std::chrono::gps_clock::from_utc(time)));152 153 test_known_values();154 test_transitions();155 test_return_type();156 157 return 0;158}159