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|
// __ _____ _____ _____
// __| | __| | | | JSON for Modern C++ (supporting code)
// | | |__ | | | | | | version 3.12.0
// |_____|_____|_____|_|___| https://github.com/nlohmann/json
//
// SPDX-FileCopyrightText: 2013-2026 Niels Lohmann <https://nlohmann.me>
// SPDX-License-Identifier: MIT
// XXX:
// Only compile these tests if 'float' and 'double' are IEEE-754 single- and
// double-precision numbers, resp.
#include "doctest_compatibility.h"
#include <nlohmann/json.hpp>
using nlohmann::detail::dtoa_impl::reinterpret_bits;
namespace
{
float make_float(uint32_t sign_bit, uint32_t biased_exponent, uint32_t significand)
{
assert(sign_bit == 0 || sign_bit == 1);
assert(biased_exponent <= 0xFF);
assert(significand <= 0x007FFFFF);
uint32_t bits = 0;
bits |= sign_bit << 31;
bits |= biased_exponent << 23;
bits |= significand;
return reinterpret_bits<float>(bits);
}
// ldexp -- convert f * 2^e to IEEE single precision
float make_float(uint64_t f, int e)
{
constexpr uint64_t kHiddenBit = 0x00800000;
constexpr uint64_t kSignificandMask = 0x007FFFFF;
constexpr int kPhysicalSignificandSize = 23; // Excludes the hidden bit.
constexpr int kExponentBias = 0x7F + kPhysicalSignificandSize;
constexpr int kDenormalExponent = 1 - kExponentBias;
constexpr int kMaxExponent = 0xFF - kExponentBias;
while (f > kHiddenBit + kSignificandMask)
{
f >>= 1;
e++;
}
if (e >= kMaxExponent)
{
return std::numeric_limits<float>::infinity();
}
if (e < kDenormalExponent)
{
return 0.0;
}
while (e > kDenormalExponent && (f & kHiddenBit) == 0)
{
f <<= 1;
e--;
}
const uint64_t biased_exponent = (e == kDenormalExponent && (f & kHiddenBit) == 0)
? 0
: static_cast<uint64_t>(e + kExponentBias);
const uint64_t bits = (f & kSignificandMask) | (biased_exponent << kPhysicalSignificandSize);
return reinterpret_bits<float>(static_cast<uint32_t>(bits));
}
double make_double(uint64_t sign_bit, uint64_t biased_exponent, uint64_t significand)
{
assert(sign_bit == 0 || sign_bit == 1);
assert(biased_exponent <= 0x7FF);
assert(significand <= 0x000FFFFFFFFFFFFF);
uint64_t bits = 0;
bits |= sign_bit << 63;
bits |= biased_exponent << 52;
bits |= significand;
return reinterpret_bits<double>(bits);
}
// ldexp -- convert f * 2^e to IEEE double precision
double make_double(uint64_t f, int e)
{
constexpr uint64_t kHiddenBit = 0x0010000000000000;
constexpr uint64_t kSignificandMask = 0x000FFFFFFFFFFFFF;
constexpr int kPhysicalSignificandSize = 52; // Excludes the hidden bit.
constexpr int kExponentBias = 0x3FF + kPhysicalSignificandSize;
constexpr int kDenormalExponent = 1 - kExponentBias;
constexpr int kMaxExponent = 0x7FF - kExponentBias;
while (f > kHiddenBit + kSignificandMask)
{
f >>= 1;
e++;
}
if (e >= kMaxExponent)
{
return std::numeric_limits<double>::infinity();
}
if (e < kDenormalExponent)
{
return 0.0;
}
while (e > kDenormalExponent && (f & kHiddenBit) == 0)
{
f <<= 1;
e--;
}
const uint64_t biased_exponent = (e == kDenormalExponent && (f & kHiddenBit) == 0)
? 0
: static_cast<uint64_t>(e + kExponentBias);
const uint64_t bits = (f & kSignificandMask) | (biased_exponent << kPhysicalSignificandSize);
return reinterpret_bits<double>(bits);
}
} // namespace
TEST_CASE("digit gen")
{
SECTION("single precision")
{
auto check_float = [](float number, const std::string & digits, int expected_exponent)
{
CAPTURE(number)
CAPTURE(digits)
CAPTURE(expected_exponent)
std::array<char, 32> buf{};
int len = 0;
int exponent = 0;
nlohmann::detail::dtoa_impl::grisu2(buf.data(), len, exponent, number);
CHECK(digits == std::string(buf.data(), buf.data() + len));
CHECK(expected_exponent == exponent);
};
check_float(make_float(0, 0, 0x00000001), "1", -45); // min denormal
check_float(make_float(0, 0, 0x007FFFFF), "11754942", -45); // max denormal
check_float(make_float(0, 1, 0x00000000), "11754944", -45); // min normal
check_float(make_float(0, 1, 0x00000001), "11754945", -45);
check_float(make_float(0, 1, 0x007FFFFF), "23509886", -45);
check_float(make_float(0, 2, 0x00000000), "23509887", -45);
check_float(make_float(0, 2, 0x00000001), "2350989", -44);
check_float(make_float(0, 24, 0x00000000), "98607613", -39); // fail if no special case in normalized boundaries
check_float(make_float(0, 30, 0x00000000), "63108872", -37); // fail if no special case in normalized boundaries
check_float(make_float(0, 31, 0x00000000), "12621775", -36); // fail if no special case in normalized boundaries
check_float(make_float(0, 57, 0x00000000), "84703295", -29); // fail if no special case in normalized boundaries
check_float(make_float(0, 254, 0x007FFFFE), "34028233", 31);
check_float(make_float(0, 254, 0x007FFFFF), "34028235", 31); // max normal
// V. Paxson and W. Kahan, "A Program for Testing IEEE Binary-Decimal Conversion", manuscript, May 1991,
// ftp://ftp.ee.lbl.gov/testbase-report.ps.Z (report)
// ftp://ftp.ee.lbl.gov/testbase.tar.Z (program)
// Table 16: Stress Inputs for Converting 24-bit Binary to Decimal, < 1/2 ULP
check_float(make_float(12676506, -102), "25", -25);
check_float(make_float(12676506, -103), "125", -26);
check_float(make_float(15445013, 86), "1195", 30);
check_float(make_float(13734123, -138), "39415", -39);
check_float(make_float(12428269, -130), "913085", -38);
check_float(make_float(15334037, -146), "1719005", -43);
check_float(make_float(11518287, -41), "52379105", -13);
check_float(make_float(12584953, -145), "2821644", -43);
check_float(make_float(15961084, -125), "37524328", -38);
check_float(make_float(14915817, -146), "16721209", -44);
check_float(make_float(10845484, -102), "21388946", -31);
check_float(make_float(16431059, -61), "7125836", -18);
// Table 17: Stress Inputs for Converting 24-bit Binary to Decimal, > 1/2 ULP
check_float(make_float(16093626, 69), "95", 26);
check_float(make_float( 9983778, 25), "335", 12);
check_float(make_float(12745034, 104), "2585", 35);
check_float(make_float(12706553, 72), "60005", 24);
check_float(make_float(11005028, 45), "387205", 15);
check_float(make_float(15059547, 71), "3555835", 22);
check_float(make_float(16015691, -99), "25268305", -30);
check_float(make_float( 8667859, 56), "6245851", 17);
check_float(make_float(14855922, -82), "30721327", -25);
check_float(make_float(14855922, -83), "15360663", -25);
check_float(make_float(10144164, -110), "781478", -32);
check_float(make_float(13248074, 95), "52481028", 28);
}
SECTION("double precision")
{
auto check_double = [](double number, const std::string & digits, int expected_exponent)
{
CAPTURE(number)
CAPTURE(digits)
CAPTURE(expected_exponent)
std::array<char, 32> buf{};
int len = 0;
int exponent = 0;
nlohmann::detail::dtoa_impl::grisu2(buf.data(), len, exponent, number);
CHECK(digits == std::string(buf.data(), buf.data() + len));
CHECK(expected_exponent == exponent);
};
check_double(make_double(0, 0, 0x0000000000000001), "5", -324); // min denormal
check_double(make_double(0, 0, 0x000FFFFFFFFFFFFF), "2225073858507201", -323); // max denormal
check_double(make_double(0, 1, 0x0000000000000000), "22250738585072014", -324); // min normal
check_double(make_double(0, 1, 0x0000000000000001), "2225073858507202", -323);
check_double(make_double(0, 1, 0x000FFFFFFFFFFFFF), "44501477170144023", -324);
check_double(make_double(0, 2, 0x0000000000000000), "4450147717014403", -323);
check_double(make_double(0, 2, 0x0000000000000001), "4450147717014404", -323);
check_double(make_double(0, 4, 0x0000000000000000), "17800590868057611", -323); // fail if no special case in normalized boundaries
check_double(make_double(0, 5, 0x0000000000000000), "35601181736115222", -323); // fail if no special case in normalized boundaries
check_double(make_double(0, 6, 0x0000000000000000), "7120236347223045", -322); // fail if no special case in normalized boundaries
check_double(make_double(0, 10, 0x0000000000000000), "11392378155556871", -321); // fail if no special case in normalized boundaries
check_double(make_double(0, 2046, 0x000FFFFFFFFFFFFE), "17976931348623155", 292);
check_double(make_double(0, 2046, 0x000FFFFFFFFFFFFF), "17976931348623157", 292); // max normal
// Test different paths in DigitGen
check_double( 10000, "1", 4);
check_double( 1200000, "12", 5);
check_double(4.9406564584124654e-324, "5", -324); // exit integral loop
check_double(2.2250738585072009e-308, "2225073858507201", -323); // exit fractional loop
check_double( 1.82877982605164e-99, "182877982605164", -113);
check_double( 1.1505466208671903e-09, "11505466208671903", -25);
check_double( 5.5645893133766722e+20, "5564589313376672", 5);
check_double( 53.034830388866226, "53034830388866226", -15);
check_double( 0.0021066531670178605, "21066531670178605", -19);
// V. Paxson and W. Kahan, "A Program for Testing IEEE Binary-Decimal Conversion", manuscript, May 1991,
// ftp://ftp.ee.lbl.gov/testbase-report.ps.Z (report)
// ftp://ftp.ee.lbl.gov/testbase.tar.Z (program)
// Table 3: Stress Inputs for Converting 53-bit Binary to Decimal, < 1/2 ULP
check_double(make_double(8511030020275656, -342) /* 9.5e-088 */, "95", -89);
check_double(make_double(5201988407066741, -824) /* 4.65e-233 */, "465", -235);
check_double(make_double(6406892948269899, +237) /* 1.415e+087 */, "1415", 84);
check_double(make_double(8431154198732492, +72) /* 3.9815e+037 */, "39815", 33);
check_double(make_double(6475049196144587, +99) /* 4.10405e+045 */, "410405", 40);
check_double(make_double(8274307542972842, +726) /* 2.920845e+234 */, "2920845", 228);
check_double(make_double(5381065484265332, -456) /* 2.8919465e-122 */, "28919465", -129);
check_double(make_double(6761728585499734, -1057) /* 4.37877185e-303 */, "437877185", -311);
check_double(make_double(7976538478610756, +376) /* 1.227701635e+129 */, "1227701635", 120);
check_double(make_double(5982403858958067, +377) /* 1.8415524525e+129 */, "18415524525", 119);
check_double(make_double(5536995190630837, +93) /* 5.48357443505e+043 */, "548357443505", 32);
check_double(make_double(7225450889282194, +710) /* 3.891901811465e+229 */, "3891901811465", 217);
check_double(make_double(7225450889282194, +709) /* 1.9459509057325e+229 */, "19459509057325", 216);
check_double(make_double(8703372741147379, +117) /* 1.44609583816055e+051 */, "144609583816055", 37);
check_double(make_double(8944262675275217, -1001) /* 4.173677474585315e-286 */, "4173677474585315", -301);
check_double(make_double(7459803696087692, -707) /* 1.1079507728788885e-197 */, "11079507728788885", -213);
check_double(make_double(6080469016670379, -381) /* 1.234550136632744e-099 */, "1234550136632744", -114);
check_double(make_double(8385515147034757, +721) /* 9.2503171196036502e+232 */, "925031711960365", 218);
check_double(make_double(7514216811389786, -828) /* 4.1980471502848898e-234 */, "419804715028489", -248);
check_double(make_double(8397297803260511, -345) /* 1.1716315319786511e-088 */, "11716315319786511", -104);
check_double(make_double(6733459239310543, +202) /* 4.3281007284461249e+076 */, "4328100728446125", 61);
check_double(make_double(8091450587292794, -473) /* 3.3177101181600311e-127 */, "3317710118160031", -142);
// Table 4: Stress Inputs for Converting 53-bit Binary to Decimal, > 1/2 ULP
check_double(make_double(6567258882077402, +952) /* 2.5e+302 */, "25", 301);
check_double(make_double(6712731423444934, +535) /* 7.55e+176 */, "755", 174);
check_double(make_double(6712731423444934, +534) /* 3.775e+176 */, "3775", 173);
check_double(make_double(5298405411573037, -957) /* 4.3495e-273 */, "43495", -277);
check_double(make_double(5137311167659507, -144) /* 2.30365e-028 */, "230365", -33);
check_double(make_double(6722280709661868, +363) /* 1.263005e+125 */, "1263005", 119);
check_double(make_double(5344436398034927, -169) /* 7.1422105e-036 */, "71422105", -43);
check_double(make_double(8369123604277281, -853) /* 1.39345735e-241 */, "139345735", -249);
check_double(make_double(8995822108487663, -780) /* 1.414634485e-219 */, "1414634485", -228);
check_double(make_double(8942832835564782, -383) /* 4.5392779195e-100 */, "45392779195", -110);
check_double(make_double(8942832835564782, -384) /* 2.26963895975e-100 */, "226963895975", -111);
check_double(make_double(8942832835564782, -385) /* 1.134819479875e-100 */, "1134819479875", -112);
check_double(make_double(6965949469487146, -249) /* 7.7003665618895e-060 */, "77003665618895", -73);
check_double(make_double(6965949469487146, -250) /* 3.85018328094475e-060 */, "385018328094475", -74);
check_double(make_double(6965949469487146, -251) /* 1.925091640472375e-060 */, "1925091640472375", -75);
check_double(make_double(7487252720986826, +548) /* 6.8985865317742005e+180 */, "68985865317742005", 164);
check_double(make_double(5592117679628511, +164) /* 1.3076622631878654e+065 */, "13076622631878654", 49);
check_double(make_double(8887055249355788, +665) /* 1.3605202075612124e+216 */, "13605202075612124", 200);
check_double(make_double(6994187472632449, +690) /* 3.5928102174759597e+223 */, "35928102174759597", 207);
check_double(make_double(8797576579012143, +588) /* 8.9125197712484552e+192 */, "8912519771248455", 177);
check_double(make_double(7363326733505337, +272) /* 5.5876975736230114e+097 */, "55876975736230114", 81);
check_double(make_double(8549497411294502, -448) /* 1.1762578307285404e-119 */, "11762578307285404", -135);
// Table 20: Stress Inputs for Converting 56-bit Binary to Decimal, < 1/2 ULP
check_double(make_double(50883641005312716, -172) /* 8.4999999999999993e-036 */, "8499999999999999", -51);
check_double(make_double(38162730753984537, -170) /* 2.5499999999999999e-035 */, "255", -37);
check_double(make_double(50832789069151999, -101) /* 2.0049999999999997e-014 */, "20049999999999997", -30);
check_double(make_double(51822367833714164, -109) /* 7.9844999999999994e-017 */, "7984499999999999", -32);
check_double(make_double(66840152193508133, -172) /* 1.1165499999999999e-035 */, "11165499999999999", -51);
check_double(make_double(55111239245584393, -138) /* 1.581615e-025 */, "1581615", -31);
check_double(make_double(71704866733321482, -112) /* 1.3809855e-017 */, "13809855", -24);
check_double(make_double(67160949328233173, -142) /* 1.2046404499999999e-026 */, "12046404499999999", -42);
check_double(make_double(53237141308040189, -152) /* 9.3251405449999991e-030 */, "9325140544999999", -45);
check_double(make_double(62785329394975786, -112) /* 1.2092014595e-017 */, "12092014595", -27);
check_double(make_double(48367680154689523, -77) /* 3.2007045838499998e-007 */, "320070458385", -18);
check_double(make_double(42552223180606797, -102) /* 8.391946324354999e-015 */, "8391946324354999", -30);
check_double(make_double(63626356173011241, -112) /* 1.2253990460585e-017 */, "12253990460585", -30);
check_double(make_double(43566388595783643, -99) /* 6.8735641489760495e-014 */, "687356414897605", -28);
check_double(make_double(54512669636675272, -159) /* 7.459816430480385e-032 */, "7459816430480385", -47);
check_double(make_double(52306490527514614, -167) /* 2.7960588398142552e-034 */, "2796058839814255", -49);
check_double(make_double(52306490527514614, -168) /* 1.3980294199071276e-034 */, "13980294199071276", -50);
check_double(make_double(41024721590449423, -89) /* 6.6279012373057359e-011 */, "6627901237305736", -26);
check_double(make_double(37664020415894738, -132) /* 6.9177880043968072e-024 */, "6917788004396807", -39);
check_double(make_double(37549883692866294, -93) /* 3.7915693108349708e-012 */, "3791569310834971", -27);
check_double(make_double(69124110374399839, -104) /* 3.4080817676591365e-015 */, "34080817676591365", -31);
check_double(make_double(69124110374399839, -105) /* 1.7040408838295683e-015 */, "17040408838295683", -31);
// Table 21: Stress Inputs for Converting 56-bit Binary to Decimal, > 1/2 ULP
check_double(make_double(49517601571415211, -94) /* 2.4999999999999998e-012 */, "25", -13);
check_double(make_double(49517601571415211, -95) /* 1.2499999999999999e-012 */, "125", -14);
check_double(make_double(54390733528642804, -133) /* 4.9949999999999996e-024 */, "49949999999999996", -40); // shortest: 4995e-27
check_double(make_double(71805402319113924, -157) /* 3.9304999999999998e-031 */, "39304999999999998", -47); // shortest: 39305e-35
check_double(make_double(40435277969631694, -179) /* 5.2770499999999992e-038 */, "5277049999999999", -53);
check_double(make_double(57241991568619049, -165) /* 1.223955e-033 */, "1223955", -39);
check_double(make_double(65224162876242886, +58) /* 1.8799584999999998e+034 */, "18799584999999998", 18);
check_double(make_double(70173376848895368, -138) /* 2.01387715e-025 */, "201387715", -33);
check_double(make_double(37072848117383207, -99) /* 5.8490641049999989e-014 */, "5849064104999999", -29);
check_double(make_double(56845051585389697, -176) /* 5.9349003054999999e-037 */, "59349003055", -47);
check_double(make_double(54791673366936431, -145) /* 1.2284718039499998e-027 */, "12284718039499998", -43);
check_double(make_double(66800318669106231, -169) /* 8.9270767180849991e-035 */, "8927076718084999", -50);
check_double(make_double(66800318669106231, -170) /* 4.4635383590424995e-035 */, "44635383590424995", -51);
check_double(make_double(66574323440112438, -119) /* 1.0016990862549499e-019 */, "10016990862549499", -35);
check_double(make_double(65645179969330963, -173) /* 5.4829412628024647e-036 */, "5482941262802465", -51);
check_double(make_double(61847254334681076, -109) /* 9.5290783281036439e-017 */, "9529078328103644", -32);
check_double(make_double(39990712921393606, -145) /* 8.9662279366405553e-028 */, "8966227936640555", -43);
check_double(make_double(59292318184400283, -149) /* 8.3086234418058538e-029 */, "8308623441805854", -44);
check_double(make_double(69116558615326153, -143) /* 6.1985873566126555e-027 */, "61985873566126555", -43);
check_double(make_double(69116558615326153, -144) /* 3.0992936783063277e-027 */, "30992936783063277", -43);
check_double(make_double(39462549494468513, -152) /* 6.9123512506176015e-030 */, "6912351250617602", -45);
check_double(make_double(39462549494468513, -153) /* 3.4561756253088008e-030 */, "3456175625308801", -45);
}
}
TEST_CASE("formatting")
{
SECTION("single precision")
{
auto check_float = [](float number, const std::string & expected)
{
std::array<char, 33> buf{};
char* end = nlohmann::detail::to_chars(buf.data(), buf.data() + 32, number); // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
const std::string actual(buf.data(), end);
CHECK(actual == expected);
};
// %.9g
check_float( -1.2345e-22f, "-1.2345e-22" ); // -1.23450004e-22
check_float( -1.2345e-21f, "-1.2345e-21" ); // -1.23450002e-21
check_float( -1.2345e-20f, "-1.2345e-20" ); // -1.23450002e-20
check_float( -1.2345e-19f, "-1.2345e-19" ); // -1.23449999e-19
check_float( -1.2345e-18f, "-1.2345e-18" ); // -1.23449996e-18
check_float( -1.2345e-17f, "-1.2345e-17" ); // -1.23449998e-17
check_float( -1.2345e-16f, "-1.2345e-16" ); // -1.23449996e-16
check_float( -1.2345e-15f, "-1.2345e-15" ); // -1.23450002e-15
check_float( -1.2345e-14f, "-1.2345e-14" ); // -1.23450004e-14
check_float( -1.2345e-13f, "-1.2345e-13" ); // -1.23449997e-13
check_float( -1.2345e-12f, "-1.2345e-12" ); // -1.23450002e-12
check_float( -1.2345e-11f, "-1.2345e-11" ); // -1.2345e-11
check_float( -1.2345e-10f, "-1.2345e-10" ); // -1.2345e-10
check_float( -1.2345e-9f, "-1.2345e-09" ); // -1.23449995e-09
check_float( -1.2345e-8f, "-1.2345e-08" ); // -1.23449997e-08
check_float( -1.2345e-7f, "-1.2345e-07" ); // -1.23449993e-07
check_float( -1.2345e-6f, "-1.2345e-06" ); // -1.23450002e-06
check_float( -1.2345e-5f, "-1.2345e-05" ); // -1.2345e-05
check_float( -1.2345e-4f, "-0.00012345" ); // -0.000123449994
check_float( -1.2345e-3f, "-0.0012345" ); // -0.00123449997
check_float( -1.2345e-2f, "-0.012345" ); // -0.0123450002
check_float( -1.2345e-1f, "-0.12345" ); // -0.123450004
check_float( -0.0f, "-0.0" ); // -0
check_float( 0.0f, "0.0" ); // 0
check_float( 1.2345e+0f, "1.2345" ); // 1.23450005
check_float( 1.2345e+1f, "12.345" ); // 12.3450003
check_float( 1.2345e+2f, "123.45" ); // 123.449997
check_float( 1.2345e+3f, "1234.5" ); // 1234.5
check_float( 1.2345e+4f, "12345.0" ); // 12345
check_float( 1.2345e+5f, "123450.0" ); // 123450
check_float( 1.2345e+6f, "1.2345e+06" ); // 1234500
check_float( 1.2345e+7f, "1.2345e+07" ); // 12345000
check_float( 1.2345e+8f, "1.2345e+08" ); // 123450000
check_float( 1.2345e+9f, "1.2345e+09" ); // 1.23449997e+09
check_float( 1.2345e+10f, "1.2345e+10" ); // 1.23449999e+10
check_float( 1.2345e+11f, "1.2345e+11" ); // 1.23449999e+11
check_float( 1.2345e+12f, "1.2345e+12" ); // 1.23450006e+12
check_float( 1.2345e+13f, "1.2345e+13" ); // 1.23449995e+13
check_float( 1.2345e+14f, "1.2345e+14" ); // 1.23450002e+14
check_float( 1.2345e+15f, "1.2345e+15" ); // 1.23450003e+15
check_float( 1.2345e+16f, "1.2345e+16" ); // 1.23449998e+16
check_float( 1.2345e+17f, "1.2345e+17" ); // 1.23449996e+17
check_float( 1.2345e+18f, "1.2345e+18" ); // 1.23450004e+18
check_float( 1.2345e+19f, "1.2345e+19" ); // 1.23449999e+19
check_float( 1.2345e+20f, "1.2345e+20" ); // 1.23449999e+20
check_float( 1.2345e+21f, "1.2345e+21" ); // 1.23449999e+21
check_float( 1.2345e+22f, "1.2345e+22" ); // 1.23450005e+22
}
SECTION("double precision")
{
auto check_double = [](double number, const std::string & expected)
{
std::array<char, 33> buf{};
char* end = nlohmann::detail::to_chars(buf.data(), buf.data() + 32, number); // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
const std::string actual(buf.data(), end);
CHECK(actual == expected);
};
// dtoa %.15g %.17g shortest
check_double( -1.2345e-22, "-1.2345e-22" ); // -1.2345e-22 -1.2345000000000001e-22 -1.2345e-22
check_double( -1.2345e-21, "-1.2345e-21" ); // -1.2345e-21 -1.2345000000000001e-21 -1.2345e-21
check_double( -1.2345e-20, "-1.2345e-20" ); // -1.2345e-20 -1.2345e-20 -1.2345e-20
check_double( -1.2345e-19, "-1.2345e-19" ); // -1.2345e-19 -1.2345000000000001e-19 -1.2345e-19
check_double( -1.2345e-18, "-1.2345e-18" ); // -1.2345e-18 -1.2345000000000001e-18 -1.2345e-18
check_double( -1.2345e-17, "-1.2345e-17" ); // -1.2345e-17 -1.2345e-17 -1.2345e-17
check_double( -1.2345e-16, "-1.2345e-16" ); // -1.2345e-16 -1.2344999999999999e-16 -1.2345e-16
check_double( -1.2345e-15, "-1.2345e-15" ); // -1.2345e-15 -1.2345e-15 -1.2345e-15
check_double( -1.2345e-14, "-1.2345e-14" ); // -1.2345e-14 -1.2345e-14 -1.2345e-14
check_double( -1.2345e-13, "-1.2345e-13" ); // -1.2345e-13 -1.2344999999999999e-13 -1.2345e-13
check_double( -1.2345e-12, "-1.2345e-12" ); // -1.2345e-12 -1.2345e-12 -1.2345e-12
check_double( -1.2345e-11, "-1.2345e-11" ); // -1.2345e-11 -1.2345e-11 -1.2345e-11
check_double( -1.2345e-10, "-1.2345e-10" ); // -1.2345e-10 -1.2345e-10 -1.2345e-10
check_double( -1.2345e-9, "-1.2345e-09" ); // -1.2345e-09 -1.2345e-09 -1.2345e-9
check_double( -1.2345e-8, "-1.2345e-08" ); // -1.2345e-08 -1.2345000000000001e-08 -1.2345e-8
check_double( -1.2345e-7, "-1.2345e-07" ); // -1.2345e-07 -1.2345000000000001e-07 -1.2345e-7
check_double( -1.2345e-6, "-1.2345e-06" ); // -1.2345e-06 -1.2345e-06 -1.2345e-6
check_double( -1.2345e-5, "-1.2345e-05" ); // -1.2345e-05 -1.2345e-05 -1.2345e-5
check_double( -1.2345e-4, "-0.00012345" ); // -0.00012345 -0.00012344999999999999 -0.00012345
check_double( -1.2345e-3, "-0.0012345" ); // -0.0012345 -0.0012344999999999999 -0.0012345
check_double( -1.2345e-2, "-0.012345" ); // -0.012345 -0.012345 -0.012345
check_double( -1.2345e-1, "-0.12345" ); // -0.12345 -0.12345 -0.12345
check_double( -0.0, "-0.0" ); // -0 -0 -0
check_double( 0.0, "0.0" ); // 0 0 0
check_double( 1.2345e+0, "1.2345" ); // 1.2345 1.2344999999999999 1.2345
check_double( 1.2345e+1, "12.345" ); // 12.345 12.345000000000001 12.345
check_double( 1.2345e+2, "123.45" ); // 123.45 123.45 123.45
check_double( 1.2345e+3, "1234.5" ); // 1234.5 1234.5 1234.5
check_double( 1.2345e+4, "12345.0" ); // 12345 12345 12345
check_double( 1.2345e+5, "123450.0" ); // 123450 123450 123450
check_double( 1.2345e+6, "1234500.0" ); // 1234500 1234500 1234500
check_double( 1.2345e+7, "12345000.0" ); // 12345000 12345000 12345000
check_double( 1.2345e+8, "123450000.0" ); // 123450000 123450000 123450000
check_double( 1.2345e+9, "1234500000.0" ); // 1234500000 1234500000 1234500000
check_double( 1.2345e+10, "12345000000.0" ); // 12345000000 12345000000 12345000000
check_double( 1.2345e+11, "123450000000.0" ); // 123450000000 123450000000 123450000000
check_double( 1.2345e+12, "1234500000000.0" ); // 1234500000000 1234500000000 1234500000000
check_double( 1.2345e+13, "12345000000000.0" ); // 12345000000000 12345000000000 12345000000000
check_double( 1.2345e+14, "123450000000000.0" ); // 123450000000000 123450000000000 123450000000000
check_double( 1.2345e+15, "1.2345e+15" ); // 1.2345e+15 1234500000000000 1.2345e15
check_double( 1.2345e+16, "1.2345e+16" ); // 1.2345e+16 12345000000000000 1.2345e16
check_double( 1.2345e+17, "1.2345e+17" ); // 1.2345e+17 1.2345e+17 1.2345e17
check_double( 1.2345e+18, "1.2345e+18" ); // 1.2345e+18 1.2345e+18 1.2345e18
check_double( 1.2345e+19, "1.2345e+19" ); // 1.2345e+19 1.2345e+19 1.2345e19
check_double( 1.2345e+20, "1.2345e+20" ); // 1.2345e+20 1.2345e+20 1.2345e20
check_double( 1.2345e+21, "1.2344999999999999e+21" ); // 1.2345e+21 1.2344999999999999e+21 1.2345e21
check_double( 1.2345e+22, "1.2345e+22" ); // 1.2345e+22 1.2345e+22 1.2345e22
}
SECTION("integer")
{
auto check_integer = [](std::int64_t number, const std::string & expected)
{
const nlohmann::json j = number;
CHECK(j.dump() == expected);
};
// edge cases
check_integer(INT64_MIN, "-9223372036854775808");
check_integer(INT64_MAX, "9223372036854775807");
// few random big integers
check_integer(-3456789012345678901LL, "-3456789012345678901");
check_integer(3456789012345678901LL, "3456789012345678901");
check_integer(-5678901234567890123LL, "-5678901234567890123");
check_integer(5678901234567890123LL, "5678901234567890123");
// integers with various digit counts
check_integer(-1000000000000000000LL, "-1000000000000000000");
check_integer(-100000000000000000LL, "-100000000000000000");
check_integer(-10000000000000000LL, "-10000000000000000");
check_integer(-1000000000000000LL, "-1000000000000000");
check_integer(-100000000000000LL, "-100000000000000");
check_integer(-10000000000000LL, "-10000000000000");
check_integer(-1000000000000LL, "-1000000000000");
check_integer(-100000000000LL, "-100000000000");
check_integer(-10000000000LL, "-10000000000");
check_integer(-1000000000LL, "-1000000000");
check_integer(-100000000LL, "-100000000");
check_integer(-10000000LL, "-10000000");
check_integer(-1000000LL, "-1000000");
check_integer(-100000LL, "-100000");
check_integer(-10000LL, "-10000");
check_integer(-1000LL, "-1000");
check_integer(-100LL, "-100");
check_integer(-10LL, "-10");
check_integer(-1LL, "-1");
check_integer(0, "0");
check_integer(1LL, "1");
check_integer(10LL, "10");
check_integer(100LL, "100");
check_integer(1000LL, "1000");
check_integer(10000LL, "10000");
check_integer(100000LL, "100000");
check_integer(1000000LL, "1000000");
check_integer(10000000LL, "10000000");
check_integer(100000000LL, "100000000");
check_integer(1000000000LL, "1000000000");
check_integer(10000000000LL, "10000000000");
check_integer(100000000000LL, "100000000000");
check_integer(1000000000000LL, "1000000000000");
check_integer(10000000000000LL, "10000000000000");
check_integer(100000000000000LL, "100000000000000");
check_integer(1000000000000000LL, "1000000000000000");
check_integer(10000000000000000LL, "10000000000000000");
check_integer(100000000000000000LL, "100000000000000000");
check_integer(1000000000000000000LL, "1000000000000000000");
}
}
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