libcxx/test/std/utilities/charconv/charconv.msvc/float_to_chars_test_cases.hpp

   1 // Copyright (c) Microsoft Corporation.
   2 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   3
   4
   5 // Copyright 2018 Ulf Adams
   6 // Copyright (c) Microsoft Corporation. All rights reserved.
   7
   8 // Boost Software License - Version 1.0 - August 17th, 2003
   9
  10 // Permission is hereby granted, free of charge, to any person or organization
  11 // obtaining a copy of the software and accompanying documentation covered by
  12 // this license (the "Software") to use, reproduce, display, distribute,
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  14 // Software, and to permit third-parties to whom the Software is furnished to
  15 // do so, all subject to the following:
  16
  17 // The copyright notices in the Software and this entire statement, including
  18 // the above license grant, this restriction and the following disclaimer,
  19 // must be included in all copies of the Software, in whole or in part, and
  20 // all derivative works of the Software, unless such copies or derivative
  21 // works are solely in the form of machine-executable object code generated by
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  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  25 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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  31
  32
  33 // This file contains test cases derived from:
  34 // https://github.com/ulfjack/ryu
  35 // See xcharconv_ryu.h for the exact commit.
  36 // (Keep the cgmanifest.json commitHash in sync.)
  37
  38
  39 #ifndef FLOAT_TO_CHARS_TEST_CASES_HPP
  40 #define FLOAT_TO_CHARS_TEST_CASES_HPP
  41
  42 #include <charconv>
  43
  44 #include "test.hpp"
  45 using namespace std;
  46
  47 inline constexpr FloatToCharsTestCase float_to_chars_test_cases[] = {
  48     // Test special cases (zero, inf, nan) and an ordinary case. Also test negative signs.
  49     {0.0f, chars_format::scientific, "0e+00"},
  50     {-0.0f, chars_format::scientific, "-0e+00"},
  51     {float_inf, chars_format::scientific, "inf"},
  52     {-float_inf, chars_format::scientific, "-inf"},
  53     {float_nan, chars_format::scientific, "nan"},
  54     {-float_nan, chars_format::scientific, "-nan(ind)"},
  55     {float_nan_payload, chars_format::scientific, "nan"},
  56     {-float_nan_payload, chars_format::scientific, "-nan"},
  57     {2.018f, chars_format::scientific, "2.018e+00"},
  58     {-2.018f, chars_format::scientific, "-2.018e+00"},
  59
  60     // Ditto for fixed, which doesn't emit exponents.
  61     {0.0f, chars_format::fixed, "0"},
  62     {-0.0f, chars_format::fixed, "-0"},
  63     {float_inf, chars_format::fixed, "inf"},
  64     {-float_inf, chars_format::fixed, "-inf"},
  65     {float_nan, chars_format::fixed, "nan"},
  66     {-float_nan, chars_format::fixed, "-nan(ind)"},
  67     {float_nan_payload, chars_format::fixed, "nan"},
  68     {-float_nan_payload, chars_format::fixed, "-nan"},
  69     {2.018f, chars_format::fixed, "2.018"},
  70     {-2.018f, chars_format::fixed, "-2.018"},
  71
  72     // Ditto for general, which selects fixed for the scientific exponent 0.
  73     {0.0f, chars_format::general, "0"},
  74     {-0.0f, chars_format::general, "-0"},
  75     {float_inf, chars_format::general, "inf"},
  76     {-float_inf, chars_format::general, "-inf"},
  77     {float_nan, chars_format::general, "nan"},
  78     {-float_nan, chars_format::general, "-nan(ind)"},
  79     {float_nan_payload, chars_format::general, "nan"},
  80     {-float_nan_payload, chars_format::general, "-nan"},
  81     {2.018f, chars_format::general, "2.018"},
  82     {-2.018f, chars_format::general, "-2.018"},
  83
  84     // Ditto for plain, which selects fixed because it's shorter for these values.
  85     {0.0f, chars_format{}, "0"},
  86     {-0.0f, chars_format{}, "-0"},
  87     {float_inf, chars_format{}, "inf"},
  88     {-float_inf, chars_format{}, "-inf"},
  89     {float_nan, chars_format{}, "nan"},
  90     {-float_nan, chars_format{}, "-nan(ind)"},
  91     {float_nan_payload, chars_format{}, "nan"},
  92     {-float_nan_payload, chars_format{}, "-nan"},
  93     {2.018f, chars_format{}, "2.018"},
  94     {-2.018f, chars_format{}, "-2.018"},
  95
  96     // Ditto for hex.
  97     {0.0f, chars_format::hex, "0p+0"},
  98     {-0.0f, chars_format::hex, "-0p+0"},
  99     {float_inf, chars_format::hex, "inf"},
 100     {-float_inf, chars_format::hex, "-inf"},
 101     {float_nan, chars_format::hex, "nan"},
 102     {-float_nan, chars_format::hex, "-nan(ind)"},
 103     {float_nan_payload, chars_format::hex, "nan"},
 104     {-float_nan_payload, chars_format::hex, "-nan"},
 105     {0x1.729p+0f, chars_format::hex, "1.729p+0"},
 106     {-0x1.729p+0f, chars_format::hex, "-1.729p+0"},
 107
 108     // Ryu f2s_test.cc SwitchToSubnormal
 109     {1.1754944e-38f, chars_format::scientific, "1.1754944e-38"},
 110
 111     // Ryu f2s_test.cc MinAndMax
 112     {0x1.fffffep+127f, chars_format::scientific, "3.4028235e+38"},
 113     {0x1.000000p-149f, chars_format::scientific, "1e-45"},
 114
 115     // Ryu f2s_test.cc BoundaryRoundEven
 116     {3.355445e7f, chars_format::scientific, "3.355445e+07"},
 117     {8.999999e9f, chars_format::scientific, "9e+09"},
 118     {3.4366717e10f, chars_format::scientific, "3.436672e+10"},
 119
 120     // Ryu f2s_test.cc ExactValueRoundEven
 121     {3.0540412e5f, chars_format::scientific, "3.0540412e+05"},
 122     {8.0990312e3f, chars_format::scientific, "8.0990312e+03"},
 123
 124     // Ryu f2s_test.cc LotsOfTrailingZeros
 125     {2.4414062e-4f, chars_format::scientific, "2.4414062e-04"},
 126     {2.4414062e-3f, chars_format::scientific, "2.4414062e-03"},
 127     {4.3945312e-3f, chars_format::scientific, "4.3945312e-03"},
 128     {6.3476562e-3f, chars_format::scientific, "6.3476562e-03"},
 129
 130     // Ryu f2s_test.cc Regression
 131     {4.7223665e21f, chars_format::scientific, "4.7223665e+21"},
 132     {8388608.0f, chars_format::scientific, "8.388608e+06"},
 133     {1.6777216e7f, chars_format::scientific, "1.6777216e+07"},
 134     {3.3554436e7f, chars_format::scientific, "3.3554436e+07"},
 135     {6.7131496e7f, chars_format::scientific, "6.7131496e+07"},
 136     {1.9310392e-38f, chars_format::scientific, "1.9310392e-38"},
 137     {-2.47e-43f, chars_format::scientific, "-2.47e-43"},
 138     {1.993244e-38f, chars_format::scientific, "1.993244e-38"},
 139     {4103.9003f, chars_format::scientific, "4.1039004e+03"},
 140     {5.3399997e9f, chars_format::scientific, "5.3399997e+09"},
 141     {6.0898e-39f, chars_format::scientific, "6.0898e-39"},
 142     {0.0010310042f, chars_format::scientific, "1.0310042e-03"},
 143     {2.8823261e17f, chars_format::scientific, "2.882326e+17"},
 144     {0x1.5c87fap-84f, chars_format::scientific, "7.038531e-26"}, // TRANSITION, VSO-629490, should be 7.038531e-26f
 145     {9.2234038e17f, chars_format::scientific, "9.223404e+17"},
 146     {6.7108872e7f, chars_format::scientific, "6.710887e+07"},
 147     {1.0e-44f, chars_format::scientific, "1e-44"},
 148     {2.816025e14f, chars_format::scientific, "2.816025e+14"},
 149     {9.223372e18f, chars_format::scientific, "9.223372e+18"},
 150     {1.5846085e29f, chars_format::scientific, "1.5846086e+29"},
 151     {1.1811161e19f, chars_format::scientific, "1.1811161e+19"},
 152     {5.368709e18f, chars_format::scientific, "5.368709e+18"},
 153     {4.6143165e18f, chars_format::scientific, "4.6143166e+18"},
 154     {0.007812537f, chars_format::scientific, "7.812537e-03"},
 155     {1.4e-45f, chars_format::scientific, "1e-45"},
 156     {1.18697724e20f, chars_format::scientific, "1.18697725e+20"},
 157     {1.00014165e-36f, chars_format::scientific, "1.00014165e-36"},
 158     {200.0f, chars_format::scientific, "2e+02"},
 159     {3.3554432e7f, chars_format::scientific, "3.3554432e+07"},
 160
 161     // Ryu f2s_test.cc LooksLikePow5
 162     {0x1.2a05f2p+59f, chars_format::scientific, "6.7108864e+17"},
 163     {0x1.2a05f2p+60f, chars_format::scientific, "1.3421773e+18"},
 164     {0x1.2a05f2p+61f, chars_format::scientific, "2.6843546e+18"},
 165
 166     // Ryu f2s_test.cc OutputLength
 167     {1.0f, chars_format::scientific, "1e+00"},
 168     {1.2f, chars_format::scientific, "1.2e+00"},
 169     {1.23f, chars_format::scientific, "1.23e+00"},
 170     {1.234f, chars_format::scientific, "1.234e+00"},
 171     {1.2345f, chars_format::scientific, "1.2345e+00"},
 172     {1.23456f, chars_format::scientific, "1.23456e+00"},
 173     {1.234567f, chars_format::scientific, "1.234567e+00"},
 174     {1.2345678f, chars_format::scientific, "1.2345678e+00"},
 175     {1.23456735e-36f, chars_format::scientific, "1.23456735e-36"},
 176
 177     // Test all exponents.
 178     {1.729e-45f, chars_format::scientific, "1e-45"},
 179     {1.729e-44f, chars_format::scientific, "1.7e-44"},
 180     {1.729e-43f, chars_format::scientific, "1.72e-43"},
 181     {1.729e-42f, chars_format::scientific, "1.729e-42"},
 182     {1.729e-41f, chars_format::scientific, "1.729e-41"},
 183     {1.729e-40f, chars_format::scientific, "1.729e-40"},
 184     {1.729e-39f, chars_format::scientific, "1.729e-39"},
 185     {1.729e-38f, chars_format::scientific, "1.729e-38"},
 186     {1.729e-37f, chars_format::scientific, "1.729e-37"},
 187     {1.729e-36f, chars_format::scientific, "1.729e-36"},
 188     {1.729e-35f, chars_format::scientific, "1.729e-35"},
 189     {1.729e-34f, chars_format::scientific, "1.729e-34"},
 190     {1.729e-33f, chars_format::scientific, "1.729e-33"},
 191     {1.729e-32f, chars_format::scientific, "1.729e-32"},
 192     {1.729e-31f, chars_format::scientific, "1.729e-31"},
 193     {1.729e-30f, chars_format::scientific, "1.729e-30"},
 194     {1.729e-29f, chars_format::scientific, "1.729e-29"},
 195     {1.729e-28f, chars_format::scientific, "1.729e-28"},
 196     {1.729e-27f, chars_format::scientific, "1.729e-27"},
 197     {1.729e-26f, chars_format::scientific, "1.729e-26"},
 198     {1.729e-25f, chars_format::scientific, "1.729e-25"},
 199     {1.729e-24f, chars_format::scientific, "1.729e-24"},
 200     {1.729e-23f, chars_format::scientific, "1.729e-23"},
 201     {1.729e-22f, chars_format::scientific, "1.729e-22"},
 202     {1.729e-21f, chars_format::scientific, "1.729e-21"},
 203     {1.729e-20f, chars_format::scientific, "1.729e-20"},
 204     {1.729e-19f, chars_format::scientific, "1.729e-19"},
 205     {1.729e-18f, chars_format::scientific, "1.729e-18"},
 206     {1.729e-17f, chars_format::scientific, "1.729e-17"},
 207     {1.729e-16f, chars_format::scientific, "1.729e-16"},
 208     {1.729e-15f, chars_format::scientific, "1.729e-15"},
 209     {1.729e-14f, chars_format::scientific, "1.729e-14"},
 210     {1.729e-13f, chars_format::scientific, "1.729e-13"},
 211     {1.729e-12f, chars_format::scientific, "1.729e-12"},
 212     {1.729e-11f, chars_format::scientific, "1.729e-11"},
 213     {1.729e-10f, chars_format::scientific, "1.729e-10"},
 214     {1.729e-9f, chars_format::scientific, "1.729e-09"},
 215     {1.729e-8f, chars_format::scientific, "1.729e-08"},
 216     {1.729e-7f, chars_format::scientific, "1.729e-07"},
 217     {1.729e-6f, chars_format::scientific, "1.729e-06"},
 218     {1.729e-5f, chars_format::scientific, "1.729e-05"},
 219     {1.729e-4f, chars_format::scientific, "1.729e-04"},
 220     {1.729e-3f, chars_format::scientific, "1.729e-03"},
 221     {1.729e-2f, chars_format::scientific, "1.729e-02"},
 222     {1.729e-1f, chars_format::scientific, "1.729e-01"},
 223     {1.729e0f, chars_format::scientific, "1.729e+00"},
 224     {1.729e1f, chars_format::scientific, "1.729e+01"},
 225     {1.729e2f, chars_format::scientific, "1.729e+02"},
 226     {1.729e3f, chars_format::scientific, "1.729e+03"},
 227     {1.729e4f, chars_format::scientific, "1.729e+04"},
 228     {1.729e5f, chars_format::scientific, "1.729e+05"},
 229     {1.729e6f, chars_format::scientific, "1.729e+06"},
 230     {1.729e7f, chars_format::scientific, "1.729e+07"},
 231     {1.729e8f, chars_format::scientific, "1.729e+08"},
 232     {1.729e9f, chars_format::scientific, "1.729e+09"},
 233     {1.729e10f, chars_format::scientific, "1.729e+10"},
 234     {1.729e11f, chars_format::scientific, "1.729e+11"},
 235     {1.729e12f, chars_format::scientific, "1.729e+12"},
 236     {1.729e13f, chars_format::scientific, "1.729e+13"},
 237     {1.729e14f, chars_format::scientific, "1.729e+14"},
 238     {1.729e15f, chars_format::scientific, "1.729e+15"},
 239     {1.729e16f, chars_format::scientific, "1.729e+16"},
 240     {1.729e17f, chars_format::scientific, "1.729e+17"},
 241     {1.729e18f, chars_format::scientific, "1.729e+18"},
 242     {1.729e19f, chars_format::scientific, "1.729e+19"},
 243     {1.729e20f, chars_format::scientific, "1.729e+20"},
 244     {1.729e21f, chars_format::scientific, "1.729e+21"},
 245     {1.729e22f, chars_format::scientific, "1.729e+22"},
 246     {1.729e23f, chars_format::scientific, "1.729e+23"},
 247     {1.729e24f, chars_format::scientific, "1.729e+24"},
 248     {1.729e25f, chars_format::scientific, "1.729e+25"},
 249     {1.729e26f, chars_format::scientific, "1.729e+26"},
 250     {1.729e27f, chars_format::scientific, "1.729e+27"},
 251     {1.729e28f, chars_format::scientific, "1.729e+28"},
 252     {1.729e29f, chars_format::scientific, "1.729e+29"},
 253     {1.729e30f, chars_format::scientific, "1.729e+30"},
 254     {1.729e31f, chars_format::scientific, "1.729e+31"},
 255     {1.729e32f, chars_format::scientific, "1.729e+32"},
 256     {1.729e33f, chars_format::scientific, "1.729e+33"},
 257     {1.729e34f, chars_format::scientific, "1.729e+34"},
 258     {1.729e35f, chars_format::scientific, "1.729e+35"},
 259     {1.729e36f, chars_format::scientific, "1.729e+36"},
 260     {1.729e37f, chars_format::scientific, "1.729e+37"},
 261     {1.729e38f, chars_format::scientific, "1.729e+38"},
 262
 263     // Test all of the cases for fixed notation, including the non-Ryu fallback for large integers.
 264     {1.729e-4f, chars_format::fixed, "0.0001729"},
 265     {1.729e-3f, chars_format::fixed, "0.001729"},
 266     {1.729e-2f, chars_format::fixed, "0.01729"},
 267     {1.729e-1f, chars_format::fixed, "0.1729"},
 268     {1.729e0f, chars_format::fixed, "1.729"},
 269     {1.729e1f, chars_format::fixed, "17.29"},
 270     {1.729e2f, chars_format::fixed, "172.9"},
 271     {1.729e3f, chars_format::fixed, "1729"},
 272     {1.729e4f, chars_format::fixed, "17290"},
 273     {1.729e5f, chars_format::fixed, "172900"},
 274     {1.729e6f, chars_format::fixed, "1729000"},
 275     {1.729e7f, chars_format::fixed, "17290000"},
 276     {1.729e8f, chars_format::fixed, "172900000"},
 277     {1.729e9f, chars_format::fixed, "1728999936"},
 278     {1.729e10f, chars_format::fixed, "17290000384"},
 279     {1.729e11f, chars_format::fixed, "172900007936"},
 280     {1.729e12f, chars_format::fixed, "1728999981056"},
 281     {1.729e13f, chars_format::fixed, "17290000072704"},
 282     {1.729e14f, chars_format::fixed, "172899998629888"},
 283     {1.729e15f, chars_format::fixed, "1729000019853312"},
 284     {1.729e16f, chars_format::fixed, "17289999661662208"},
 285     {1.729e17f, chars_format::fixed, "172900007354040320"},
 286     {1.729e18f, chars_format::fixed, "1729000039180664832"},
 287     {1.729e19f, chars_format::fixed, "17289999567172927488"},
 288     {1.729e20f, chars_format::fixed, "172899997870752530432"},
 289     {1.729e21f, chars_format::fixed, "1729000013891897393152"},
 290     {1.729e22f, chars_format::fixed, "17290000138918973931520"},
 291     {1.729e23f, chars_format::fixed, "172899999137389925629952"},
 292     {1.729e24f, chars_format::fixed, "1729000063431493294227456"},
 293     {1.729e25f, chars_format::fixed, "17289999481393428335427584"},
 294     {1.729e26f, chars_format::fixed, "172900004037306320209051648"},
 295     {1.729e27f, chars_format::fixed, "1729000040373063202090516480"},
 296     {1.729e28f, chars_format::fixed, "17290000403730632020905164800"},
 297     {1.729e29f, chars_format::fixed, "172900004037306320209051648000"},
 298     {1.729e30f, chars_format::fixed, "1728999964815199476176193060864"},
 299     {1.729e31f, chars_format::fixed, "17290000252614904569076517961728"},
 300     {1.729e32f, chars_format::fixed, "172899990436890849544473432555520"},
 301     {1.729e33f, chars_format::fixed, "1729000059111413406117268687945728"},
 302     {1.729e34f, chars_format::fixed, "17290000281629124239827618154676224"},
 303     {1.729e35f, chars_format::fixed, "172899995388651006685994532152016896"},
 304     {1.729e36f, chars_format::fixed, "1728999993500591323992114118292144128"},
 305     {1.729e37f, chars_format::fixed, "17289999935005913239921141182921441280"},
 306     {1.729e38f, chars_format::fixed, "172899996814757931942752608835808002048"},
 307
 308     // Also test one-digit cases, where the decimal point can't appear between digits like "17.29".
 309     {7e-3f, chars_format::fixed, "0.007"},
 310     {7e-2f, chars_format::fixed, "0.07"},
 311     {7e-1f, chars_format::fixed, "0.7"},
 312     {7e0f, chars_format::fixed, "7"},
 313     {7e1f, chars_format::fixed, "70"},
 314     {7e2f, chars_format::fixed, "700"},
 315     {7e3f, chars_format::fixed, "7000"},
 316
 317     // Test the maximum value in fixed notation.
 318     {0x1.fffffep+127f, chars_format::fixed, "340282346638528859811704183484516925440"},
 319
 320     // Test highly-trimmed powers of 2.
 321     {0x1p118f, chars_format::fixed, "332306998946228968225951765070086144"},
 322     {0x1p118f, chars_format::scientific, "3.32307e+35"},
 323     {0x1p119f, chars_format::fixed, "664613997892457936451903530140172288"},
 324     {0x1p119f, chars_format::scientific, "6.64614e+35"},
 325
 326     // Test powers of 10 that are exactly representable.
 327     {1e0f, chars_format::fixed, "1"},
 328     {1e1f, chars_format::fixed, "10"},
 329     {1e2f, chars_format::fixed, "100"},
 330     {1e3f, chars_format::fixed, "1000"},
 331     {1e4f, chars_format::fixed, "10000"},
 332     {1e5f, chars_format::fixed, "100000"},
 333     {1e6f, chars_format::fixed, "1000000"},
 334     {1e7f, chars_format::fixed, "10000000"},
 335     {1e8f, chars_format::fixed, "100000000"},
 336     {1e9f, chars_format::fixed, "1000000000"},
 337     {1e10f, chars_format::fixed, "10000000000"},
 338
 339     // Test powers of 10 that aren't exactly representable.
 340     // This exercises the "adjustment" code.
 341     {1e11f, chars_format::fixed, "99999997952"},
 342     {1e12f, chars_format::fixed, "999999995904"},
 343     {1e13f, chars_format::fixed, "9999999827968"},
 344     {1e14f, chars_format::fixed, "100000000376832"},
 345     {1e15f, chars_format::fixed, "999999986991104"},
 346     {1e16f, chars_format::fixed, "10000000272564224"},
 347     {1e17f, chars_format::fixed, "99999998430674944"},
 348     {1e18f, chars_format::fixed, "999999984306749440"},
 349     {1e19f, chars_format::fixed, "9999999980506447872"},
 350     {1e20f, chars_format::fixed, "100000002004087734272"},
 351     {1e21f, chars_format::fixed, "1000000020040877342720"},
 352     {1e22f, chars_format::fixed, "9999999778196308361216"},
 353     {1e23f, chars_format::fixed, "99999997781963083612160"},
 354     {1e24f, chars_format::fixed, "1000000013848427855085568"},
 355     {1e25f, chars_format::fixed, "9999999562023526247432192"},
 356     {1e26f, chars_format::fixed, "100000002537764290115403776"},
 357     {1e27f, chars_format::fixed, "999999988484154753734934528"},
 358     {1e28f, chars_format::fixed, "9999999442119689768320106496"},
 359     {1e29f, chars_format::fixed, "100000001504746621987668885504"},
 360     {1e30f, chars_format::fixed, "1000000015047466219876688855040"},
 361     {1e31f, chars_format::fixed, "9999999848243207295109594873856"},
 362     {1e32f, chars_format::fixed, "100000003318135351409612647563264"},
 363     {1e33f, chars_format::fixed, "999999994495727286427992885035008"},
 364     {1e34f, chars_format::fixed, "9999999790214767953607394487959552"},
 365     {1e35f, chars_format::fixed, "100000004091847875962975319375216640"},
 366     {1e36f, chars_format::fixed, "999999961690316245365415600208216064"},
 367     {1e37f, chars_format::fixed, "9999999933815812510711506376257961984"},
 368     {1e38f, chars_format::fixed, "99999996802856924650656260769173209088"},
 369
 370     // These numbers have odd mantissas (unaffected by shifting)
 371     // that are barely within the "max shifted mantissa" limit.
 372     // They're exactly-representable multiples of powers of 10, and can use Ryu with zero-filling.
 373     {3355443e1f, chars_format::fixed, "33554430"},
 374     {671087e2f, chars_format::fixed, "67108700"},
 375     {134217e3f, chars_format::fixed, "134217000"},
 376     {26843e4f, chars_format::fixed, "268430000"},
 377     {5367e5f, chars_format::fixed, "536700000"},
 378     {1073e6f, chars_format::fixed, "1073000000"},
 379     {213e7f, chars_format::fixed, "2130000000"},
 380     {41e8f, chars_format::fixed, "4100000000"},
 381     {7e9f, chars_format::fixed, "7000000000"},
 382     {1e10f, chars_format::fixed, "10000000000"},
 383
 384     // These numbers have odd mantissas (unaffected by shifting)
 385     // that are barely above the "max shifted mantissa" limit.
 386     // This activates the non-Ryu fallback for large integers.
 387     {3355445e1f, chars_format::fixed, "33554448"},
 388     {671089e2f, chars_format::fixed, "67108896"},
 389     {134219e3f, chars_format::fixed, "134219008"},
 390     {26845e4f, chars_format::fixed, "268449984"},
 391     {5369e5f, chars_format::fixed, "536899968"},
 392     {1075e6f, chars_format::fixed, "1075000064"},
 393     {215e7f, chars_format::fixed, "2150000128"},
 394     {43e8f, chars_format::fixed, "4300000256"},
 395     {9e9f, chars_format::fixed, "8999999488"},
 396     {3e10f, chars_format::fixed, "30000001024"},
 397
 398     // Test the mantissa shifting logic.
 399     {5495808e5f, chars_format::fixed, "549580800000"}, // 5367 * 2^10
 400     {5497856e5f, chars_format::fixed, "549785567232"}, // 5369 * 2^10
 401
 402     // Inspect all of those numbers in scientific notation.
 403     // For the within-limit numbers, this verifies that Ryu is actually being used with zero-filling above.
 404     // For the above-limit numbers, this tests Ryu's trimming.
 405     {3355443e1f, chars_format::scientific, "3.355443e+07"},
 406     {671087e2f, chars_format::scientific, "6.71087e+07"},
 407     {134217e3f, chars_format::scientific, "1.34217e+08"},
 408     {26843e4f, chars_format::scientific, "2.6843e+08"},
 409     {5367e5f, chars_format::scientific, "5.367e+08"},
 410     {1073e6f, chars_format::scientific, "1.073e+09"},
 411     {213e7f, chars_format::scientific, "2.13e+09"},
 412     {41e8f, chars_format::scientific, "4.1e+09"},
 413     {7e9f, chars_format::scientific, "7e+09"},
 414     {1e10f, chars_format::scientific, "1e+10"},
 415     {3355445e1f, chars_format::scientific, "3.355445e+07"},
 416     {671089e2f, chars_format::scientific, "6.71089e+07"},
 417     {134219e3f, chars_format::scientific, "1.34219e+08"},
 418     {26845e4f, chars_format::scientific, "2.6845e+08"},
 419     {5369e5f, chars_format::scientific, "5.369e+08"},
 420     {1075e6f, chars_format::scientific, "1.075e+09"},
 421     {215e7f, chars_format::scientific, "2.15e+09"},
 422     {43e8f, chars_format::scientific, "4.3e+09"},
 423     {9e9f, chars_format::scientific, "9e+09"},
 424     {3e10f, chars_format::scientific, "3e+10"},
 425     {5495808e5f, chars_format::scientific, "5.495808e+11"},
 426     {5497856e5f, chars_format::scientific, "5.497856e+11"},
 427
 428     // Test the switching logic of chars_format::general.
 429     // C11 7.21.6.1 "The fprintf function"/8:
 430     // "Let P equal [...] 6 if the precision is omitted [...].
 431     // Then, if a conversion with style E would have an exponent of X:
 432     // - if P > X >= -4, the conversion is with style f [...].
 433     // - otherwise, the conversion is with style e [...]."
 434     {1e-6f, chars_format::general, "1e-06"},
 435     {1e-5f, chars_format::general, "1e-05"},
 436     {1e-4f, chars_format::general, "0.0001"},
 437     {1e-3f, chars_format::general, "0.001"},
 438     {1e-2f, chars_format::general, "0.01"},
 439     {1e-1f, chars_format::general, "0.1"},
 440     {1e0f, chars_format::general, "1"},
 441     {1e1f, chars_format::general, "10"},
 442     {1e2f, chars_format::general, "100"},
 443     {1e3f, chars_format::general, "1000"},
 444     {1e4f, chars_format::general, "10000"},
 445     {1e5f, chars_format::general, "100000"},
 446     {1e6f, chars_format::general, "1e+06"},
 447     {1e7f, chars_format::general, "1e+07"},
 448     {1.234e-6f, chars_format::general, "1.234e-06"},
 449     {1.234e-5f, chars_format::general, "1.234e-05"},
 450     {1.234e-4f, chars_format::general, "0.0001234"},
 451     {1.234e-3f, chars_format::general, "0.001234"},
 452     {1.234e-2f, chars_format::general, "0.01234"},
 453     {1.234e-1f, chars_format::general, "0.1234"},
 454     {1.234e0f, chars_format::general, "1.234"},
 455     {1.234e1f, chars_format::general, "12.34"},
 456     {1.234e2f, chars_format::general, "123.4"},
 457     {1.234e3f, chars_format::general, "1234"},
 458     {1.234e4f, chars_format::general, "12340"},
 459     {1.234e5f, chars_format::general, "123400"},
 460     {1.234e6f, chars_format::general, "1.234e+06"},
 461     {1.234e7f, chars_format::general, "1.234e+07"},
 462     {1.234e8f, chars_format::general, "1.234e+08"},
 463     {1.234e9f, chars_format::general, "1.234e+09"},
 464     {1.234e10f, chars_format::general, "1.234e+10"},
 465
 466     // Test the switching logic of the plain overload.
 467     // N4762 19.19.2 [charconv.to.chars]/8:
 468     // "The conversion specifier is f or e, chosen according to the requirement
 469     // for a shortest representation (see above); a tie is resolved in favor of f."
 470     {1e-6f, chars_format{}, "1e-06"},
 471     {1e-5f, chars_format{}, "1e-05"},
 472     {1e-4f, chars_format{}, "1e-04"},
 473     {1e-3f, chars_format{}, "0.001"},
 474     {1e-2f, chars_format{}, "0.01"},
 475     {1e-1f, chars_format{}, "0.1"},
 476     {1e0f, chars_format{}, "1"},
 477     {1e1f, chars_format{}, "10"},
 478     {1e2f, chars_format{}, "100"},
 479     {1e3f, chars_format{}, "1000"},
 480     {1e4f, chars_format{}, "10000"},
 481     {1e5f, chars_format{}, "1e+05"},
 482     {1e6f, chars_format{}, "1e+06"},
 483     {1e7f, chars_format{}, "1e+07"},
 484     {1.234e-6f, chars_format{}, "1.234e-06"},
 485     {1.234e-5f, chars_format{}, "1.234e-05"},
 486     {1.234e-4f, chars_format{}, "0.0001234"},
 487     {1.234e-3f, chars_format{}, "0.001234"},
 488     {1.234e-2f, chars_format{}, "0.01234"},
 489     {1.234e-1f, chars_format{}, "0.1234"},
 490     {1.234e0f, chars_format{}, "1.234"},
 491     {1.234e1f, chars_format{}, "12.34"},
 492     {1.234e2f, chars_format{}, "123.4"},
 493     {1.234e3f, chars_format{}, "1234"},
 494     {1.234e4f, chars_format{}, "12340"},
 495     {1.234e5f, chars_format{}, "123400"},
 496     {1.234e6f, chars_format{}, "1234000"},
 497     {1.234e7f, chars_format{}, "12340000"},
 498     {1.234e8f, chars_format{}, "123400000"},
 499     {1.234e9f, chars_format{}, "1.234e+09"},
 500     {1.234e10f, chars_format{}, "1.234e+10"},
 501
 502     // Test hexfloat corner cases.
 503     {0x1.728p+0f, chars_format::hex, "1.728p+0"}, // instead of "2.e5p-1"
 504     {0x0.000002p-126f, chars_format::hex, "0.000002p-126"}, // instead of "1p-149", min subnormal
 505     {0x0.fffffep-126f, chars_format::hex, "0.fffffep-126"}, // max subnormal
 506     {0x1p-126f, chars_format::hex, "1p-126"}, // min normal
 507     {0x1.fffffep+127f, chars_format::hex, "1.fffffep+127"}, // max normal
 508
 509     // Test hexfloat exponents.
 510     {0x1p-109f, chars_format::hex, "1p-109"},
 511     {0x1p-99f, chars_format::hex, "1p-99"},
 512     {0x1p-9f, chars_format::hex, "1p-9"},
 513     {0x1p+0f, chars_format::hex, "1p+0"},
 514     {0x1p+9f, chars_format::hex, "1p+9"},
 515     {0x1p+99f, chars_format::hex, "1p+99"},
 516     {0x1p+109f, chars_format::hex, "1p+109"},
 517
 518     // Test hexfloat hexits.
 519     {0x1.0123p+0f, chars_format::hex, "1.0123p+0"},
 520     {0x1.4567p+0f, chars_format::hex, "1.4567p+0"},
 521     {0x1.89abp+0f, chars_format::hex, "1.89abp+0"},
 522     {0x1.cdefp+0f, chars_format::hex, "1.cdefp+0"},
 523
 524     // Test hexfloat trimming.
 525     {0x1.00000ap+0f, chars_format::hex, "1.00000ap+0"},
 526     {0x1.0000ap+0f, chars_format::hex, "1.0000ap+0"},
 527     {0x1.000ap+0f, chars_format::hex, "1.000ap+0"},
 528     {0x1.00ap+0f, chars_format::hex, "1.00ap+0"},
 529     {0x1.0ap+0f, chars_format::hex, "1.0ap+0"},
 530     {0x1.ap+0f, chars_format::hex, "1.ap+0"},
 531     {0x1p+0f, chars_format::hex, "1p+0"},
 532
 533     // https://www.exploringbinary.com/the-shortest-decimal-string-that-round-trips-may-not-be-the-nearest/
 534     // This is an exhaustive list of anomalous values.
 535     // (See double_to_chars_test_cases.hpp for more details.)
 536     {0x1p90f, chars_format::scientific, "1.2379401e+27"},
 537     {0x1p87f, chars_format::scientific, "1.5474251e+26"},
 538     {0x1p-96f, chars_format::scientific, "1.2621775e-29"},
 539 };
 540
 541 #endif // FLOAT_TO_CHARS_TEST_CASES_HPP