diff options
Diffstat (limited to 'absl/time/duration_test.cc')
| -rw-r--r-- | absl/time/duration_test.cc | 124 |
1 files changed, 108 insertions, 16 deletions
diff --git a/absl/time/duration_test.cc b/absl/time/duration_test.cc index 704684edb3..7ae25dc68f 100644 --- a/absl/time/duration_test.cc +++ b/absl/time/duration_test.cc @@ -16,7 +16,9 @@ #include <cmath> #include <cstdint> #include <ctime> +#include <iomanip> #include <limits> +#include <random> #include <string> #include "gmock/gmock.h" @@ -105,22 +107,22 @@ TEST(Duration, Factories) { } TEST(Duration, ToConversion) { -#define TEST_DURATION_CONVERSION(UNIT) \ - do { \ - const absl::Duration d = absl::UNIT(1.5); \ - const absl::Duration z = absl::ZeroDuration(); \ - const absl::Duration inf = absl::InfiniteDuration(); \ - const double dbl_inf = std::numeric_limits<double>::infinity(); \ - EXPECT_EQ(kint64min, absl::ToInt64##UNIT(-inf)); \ - EXPECT_EQ(-1, absl::ToInt64##UNIT(-d)); \ - EXPECT_EQ(0, absl::ToInt64##UNIT(z)); \ - EXPECT_EQ(1, absl::ToInt64##UNIT(d)); \ - EXPECT_EQ(kint64max, absl::ToInt64##UNIT(inf)); \ - EXPECT_EQ(-dbl_inf, absl::ToDouble##UNIT(-inf)); \ - EXPECT_EQ(-1.5, absl::ToDouble##UNIT(-d)); \ - EXPECT_EQ(0, absl::ToDouble##UNIT(z)); \ - EXPECT_EQ(1.5, absl::ToDouble##UNIT(d)); \ - EXPECT_EQ(dbl_inf, absl::ToDouble##UNIT(inf)); \ +#define TEST_DURATION_CONVERSION(UNIT) \ + do { \ + const absl::Duration d = absl::UNIT(1.5); \ + constexpr absl::Duration z = absl::ZeroDuration(); \ + constexpr absl::Duration inf = absl::InfiniteDuration(); \ + constexpr double dbl_inf = std::numeric_limits<double>::infinity(); \ + EXPECT_EQ(kint64min, absl::ToInt64##UNIT(-inf)); \ + EXPECT_EQ(-1, absl::ToInt64##UNIT(-d)); \ + EXPECT_EQ(0, absl::ToInt64##UNIT(z)); \ + EXPECT_EQ(1, absl::ToInt64##UNIT(d)); \ + EXPECT_EQ(kint64max, absl::ToInt64##UNIT(inf)); \ + EXPECT_EQ(-dbl_inf, absl::ToDouble##UNIT(-inf)); \ + EXPECT_EQ(-1.5, absl::ToDouble##UNIT(-d)); \ + EXPECT_EQ(0, absl::ToDouble##UNIT(z)); \ + EXPECT_EQ(1.5, absl::ToDouble##UNIT(d)); \ + EXPECT_EQ(dbl_inf, absl::ToDouble##UNIT(inf)); \ } while (0) TEST_DURATION_CONVERSION(Nanoseconds); @@ -1284,6 +1286,16 @@ TEST(Duration, SmallConversions) { EXPECT_EQ(absl::Nanoseconds(1), absl::Seconds(0.875e-9)); EXPECT_EQ(absl::Nanoseconds(1), absl::Seconds(1.000e-9)); + EXPECT_EQ(absl::ZeroDuration(), absl::Seconds(-0.124999999e-9)); + EXPECT_EQ(-absl::Nanoseconds(1) / 4, absl::Seconds(-0.125e-9)); + EXPECT_EQ(-absl::Nanoseconds(1) / 4, absl::Seconds(-0.250e-9)); + EXPECT_EQ(-absl::Nanoseconds(1) / 2, absl::Seconds(-0.375e-9)); + EXPECT_EQ(-absl::Nanoseconds(1) / 2, absl::Seconds(-0.500e-9)); + EXPECT_EQ(-absl::Nanoseconds(3) / 4, absl::Seconds(-0.625e-9)); + EXPECT_EQ(-absl::Nanoseconds(3) / 4, absl::Seconds(-0.750e-9)); + EXPECT_EQ(-absl::Nanoseconds(1), absl::Seconds(-0.875e-9)); + EXPECT_EQ(-absl::Nanoseconds(1), absl::Seconds(-1.000e-9)); + timespec ts; ts.tv_sec = 0; ts.tv_nsec = 0; @@ -1313,6 +1325,86 @@ TEST(Duration, SmallConversions) { EXPECT_THAT(ToTimeval(absl::Nanoseconds(2000)), TimevalMatcher(tv)); } +void VerifySameAsMul(double time_as_seconds, int* const misses) { + auto direct_seconds = absl::Seconds(time_as_seconds); + auto mul_by_one_second = time_as_seconds * absl::Seconds(1); + if (direct_seconds != mul_by_one_second) { + if (*misses > 10) return; + ASSERT_LE(++(*misses), 10) << "Too many errors, not reporting more."; + EXPECT_EQ(direct_seconds, mul_by_one_second) + << "given double time_as_seconds = " << std::setprecision(17) + << time_as_seconds; + } +} + +// For a variety of interesting durations, we find the exact point +// where one double converts to that duration, and the very next double +// converts to the next duration. For both of those points, verify that +// Seconds(point) returns the same duration as point * Seconds(1.0) +TEST(Duration, ToDoubleSecondsCheckEdgeCases) { + constexpr uint32_t kTicksPerSecond = absl::time_internal::kTicksPerSecond; + constexpr auto duration_tick = absl::time_internal::MakeDuration(0, 1u); + int misses = 0; + for (int64_t seconds = 0; seconds < 99; ++seconds) { + uint32_t tick_vals[] = {0, +999, +999999, +999999999, kTicksPerSecond - 1, + 0, 1000, 1000000, 1000000000, kTicksPerSecond, + 1, 1001, 1000001, 1000000001, kTicksPerSecond + 1, + 2, 1002, 1000002, 1000000002, kTicksPerSecond + 2, + 3, 1003, 1000003, 1000000003, kTicksPerSecond + 3, + 4, 1004, 1000004, 1000000004, kTicksPerSecond + 4, + 5, 6, 7, 8, 9}; + for (uint32_t ticks : tick_vals) { + absl::Duration s_plus_t = absl::Seconds(seconds) + ticks * duration_tick; + for (absl::Duration d : {s_plus_t, -s_plus_t}) { + absl::Duration after_d = d + duration_tick; + EXPECT_NE(d, after_d); + EXPECT_EQ(after_d - d, duration_tick); + + double low_edge = ToDoubleSeconds(d); + EXPECT_EQ(d, absl::Seconds(low_edge)); + + double high_edge = ToDoubleSeconds(after_d); + EXPECT_EQ(after_d, absl::Seconds(high_edge)); + + for (;;) { + double midpoint = low_edge + (high_edge - low_edge) / 2; + if (midpoint == low_edge || midpoint == high_edge) break; + absl::Duration mid_duration = absl::Seconds(midpoint); + if (mid_duration == d) { + low_edge = midpoint; + } else { + EXPECT_EQ(mid_duration, after_d); + high_edge = midpoint; + } + } + // Now low_edge is the highest double that converts to Duration d, + // and high_edge is the lowest double that converts to Duration after_d. + VerifySameAsMul(low_edge, &misses); + VerifySameAsMul(high_edge, &misses); + } + } + } +} + +TEST(Duration, ToDoubleSecondsCheckRandom) { + std::random_device rd; + std::seed_seq seed({rd(), rd(), rd(), rd(), rd(), rd(), rd(), rd()}); + std::mt19937_64 gen(seed); + // We want doubles distributed from 1/8ns up to 2^63, where + // as many values are tested from 1ns to 2ns as from 1sec to 2sec, + // so even distribute along a log-scale of those values, and + // exponentiate before using them. (9.223377e+18 is just slightly + // out of bounds for absl::Duration.) + std::uniform_real_distribution<double> uniform(std::log(0.125e-9), + std::log(9.223377e+18)); + int misses = 0; + for (int i = 0; i < 1000000; ++i) { + double d = std::exp(uniform(gen)); + VerifySameAsMul(d, &misses); + VerifySameAsMul(-d, &misses); + } +} + TEST(Duration, ConversionSaturation) { absl::Duration d; |