summaryrefslogtreecommitdiff
path: root/absl/strings/internal/str_format/convert_test.cc
blob: 5f198059fe5f6fcde1f17582ce22bf610d78122c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <cctype>
#include <cmath>
#include <string>

#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/base/internal/raw_logging.h"
#include "absl/strings/internal/str_format/bind.h"

namespace absl {
namespace str_format_internal {
namespace {

template <typename T, size_t N>
size_t ArraySize(T (&)[N]) {
  return N;
}

std::string LengthModFor(float) { return ""; }
std::string LengthModFor(double) { return ""; }
std::string LengthModFor(long double) { return "L"; }
std::string LengthModFor(char) { return "hh"; }
std::string LengthModFor(signed char) { return "hh"; }
std::string LengthModFor(unsigned char) { return "hh"; }
std::string LengthModFor(short) { return "h"; }           // NOLINT
std::string LengthModFor(unsigned short) { return "h"; }  // NOLINT
std::string LengthModFor(int) { return ""; }
std::string LengthModFor(unsigned) { return ""; }
std::string LengthModFor(long) { return "l"; }                 // NOLINT
std::string LengthModFor(unsigned long) { return "l"; }        // NOLINT
std::string LengthModFor(long long) { return "ll"; }           // NOLINT
std::string LengthModFor(unsigned long long) { return "ll"; }  // NOLINT

std::string EscCharImpl(int v) {
  if (std::isprint(static_cast<unsigned char>(v))) {
    return std::string(1, static_cast<char>(v));
  }
  char buf[64];
  int n = snprintf(buf, sizeof(buf), "\\%#.2x",
                   static_cast<unsigned>(v & 0xff));
  assert(n > 0 && n < sizeof(buf));
  return std::string(buf, n);
}

std::string Esc(char v) { return EscCharImpl(v); }
std::string Esc(signed char v) { return EscCharImpl(v); }
std::string Esc(unsigned char v) { return EscCharImpl(v); }

template <typename T>
std::string Esc(const T &v) {
  std::ostringstream oss;
  oss << v;
  return oss.str();
}

void StrAppend(std::string *dst, const char *format, va_list ap) {
  // First try with a small fixed size buffer
  static const int kSpaceLength = 1024;
  char space[kSpaceLength];

  // It's possible for methods that use a va_list to invalidate
  // the data in it upon use.  The fix is to make a copy
  // of the structure before using it and use that copy instead.
  va_list backup_ap;
  va_copy(backup_ap, ap);
  int result = vsnprintf(space, kSpaceLength, format, backup_ap);
  va_end(backup_ap);
  if (result < kSpaceLength) {
    if (result >= 0) {
      // Normal case -- everything fit.
      dst->append(space, result);
      return;
    }
    if (result < 0) {
      // Just an error.
      return;
    }
  }

  // Increase the buffer size to the size requested by vsnprintf,
  // plus one for the closing \0.
  int length = result + 1;
  char *buf = new char[length];

  // Restore the va_list before we use it again
  va_copy(backup_ap, ap);
  result = vsnprintf(buf, length, format, backup_ap);
  va_end(backup_ap);

  if (result >= 0 && result < length) {
    // It fit
    dst->append(buf, result);
  }
  delete[] buf;
}

std::string StrPrint(const char *format, ...) {
  va_list ap;
  va_start(ap, format);
  std::string result;
  StrAppend(&result, format, ap);
  va_end(ap);
  return result;
}

class FormatConvertTest : public ::testing::Test { };

template <typename T>
void TestStringConvert(const T& str) {
  const FormatArgImpl args[] = {FormatArgImpl(str)};
  struct Expectation {
    const char *out;
    const char *fmt;
  };
  const Expectation kExpect[] = {
    {"hello",  "%1$s"      },
    {"",       "%1$.s"     },
    {"",       "%1$.0s"    },
    {"h",      "%1$.1s"    },
    {"he",     "%1$.2s"    },
    {"hello",  "%1$.10s"   },
    {" hello", "%1$6s"     },
    {"   he",  "%1$5.2s"   },
    {"he   ",  "%1$-5.2s"  },
    {"hello ", "%1$-6.10s" },
  };
  for (const Expectation &e : kExpect) {
    UntypedFormatSpecImpl format(e.fmt);
    EXPECT_EQ(e.out, FormatPack(format, absl::MakeSpan(args)));
  }
}

TEST_F(FormatConvertTest, BasicString) {
  TestStringConvert("hello");  // As char array.
  TestStringConvert(static_cast<const char*>("hello"));
  TestStringConvert(std::string("hello"));
  TestStringConvert(string_view("hello"));
}

TEST_F(FormatConvertTest, NullString) {
  const char* p = nullptr;
  UntypedFormatSpecImpl format("%s");
  EXPECT_EQ("", FormatPack(format, {FormatArgImpl(p)}));
}

TEST_F(FormatConvertTest, StringPrecision) {
  // We cap at the precision.
  char c = 'a';
  const char* p = &c;
  UntypedFormatSpecImpl format("%.1s");
  EXPECT_EQ("a", FormatPack(format, {FormatArgImpl(p)}));

  // We cap at the nul terminator.
  p = "ABC";
  UntypedFormatSpecImpl format2("%.10s");
  EXPECT_EQ("ABC", FormatPack(format2, {FormatArgImpl(p)}));
}

// Pointer formatting is implementation defined. This checks that the argument
// can be matched to `ptr`.
MATCHER_P(MatchesPointerString, ptr, "") {
  if (ptr == nullptr && arg == "(nil)") {
    return true;
  }
  void* parsed = nullptr;
  if (sscanf(arg.c_str(), "%p", &parsed) != 1) {
    ABSL_RAW_LOG(FATAL, "Could not parse %s", arg.c_str());
  }
  return ptr == parsed;
}

TEST_F(FormatConvertTest, Pointer) {
  static int x = 0;
  const int *xp = &x;
  char c = 'h';
  char *mcp = &c;
  const char *cp = "hi";
  const char *cnil = nullptr;
  const int *inil = nullptr;
  using VoidF = void (*)();
  VoidF fp = [] {}, fnil = nullptr;
  volatile char vc;
  volatile char *vcp = &vc;
  volatile char *vcnil = nullptr;
  const FormatArgImpl args_array[] = {
      FormatArgImpl(xp),   FormatArgImpl(cp),  FormatArgImpl(inil),
      FormatArgImpl(cnil), FormatArgImpl(mcp), FormatArgImpl(fp),
      FormatArgImpl(fnil), FormatArgImpl(vcp), FormatArgImpl(vcnil),
  };
  auto args = absl::MakeConstSpan(args_array);

  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%20p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%.1p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%.20p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%30.20p"), args),
              MatchesPointerString(&x));

  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%-p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%-20p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%-.1p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%.20p"), args),
              MatchesPointerString(&x));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%-30.20p"), args),
              MatchesPointerString(&x));

  // const char*
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%2$p"), args),
              MatchesPointerString(cp));
  // null const int*
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%3$p"), args),
              MatchesPointerString(nullptr));
  // null const char*
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%4$p"), args),
              MatchesPointerString(nullptr));
  // nonconst char*
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%5$p"), args),
              MatchesPointerString(mcp));

  // function pointers
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%6$p"), args),
              MatchesPointerString(reinterpret_cast<const void*>(fp)));
  EXPECT_THAT(
      FormatPack(UntypedFormatSpecImpl("%8$p"), args),
      MatchesPointerString(reinterpret_cast<volatile const void *>(vcp)));

  // null function pointers
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%7$p"), args),
              MatchesPointerString(nullptr));
  EXPECT_THAT(FormatPack(UntypedFormatSpecImpl("%9$p"), args),
              MatchesPointerString(nullptr));
}

struct Cardinal {
  enum Pos { k1 = 1, k2 = 2, k3 = 3 };
  enum Neg { kM1 = -1, kM2 = -2, kM3 = -3 };
};

TEST_F(FormatConvertTest, Enum) {
  const Cardinal::Pos k3 = Cardinal::k3;
  const Cardinal::Neg km3 = Cardinal::kM3;
  const FormatArgImpl args[] = {FormatArgImpl(k3), FormatArgImpl(km3)};
  UntypedFormatSpecImpl format("%1$d");
  UntypedFormatSpecImpl format2("%2$d");
  EXPECT_EQ("3", FormatPack(format, absl::MakeSpan(args)));
  EXPECT_EQ("-3", FormatPack(format2, absl::MakeSpan(args)));
}

template <typename T>
class TypedFormatConvertTest : public FormatConvertTest { };

TYPED_TEST_SUITE_P(TypedFormatConvertTest);

std::vector<std::string> AllFlagCombinations() {
  const char kFlags[] = {'-', '#', '0', '+', ' '};
  std::vector<std::string> result;
  for (size_t fsi = 0; fsi < (1ull << ArraySize(kFlags)); ++fsi) {
    std::string flag_set;
    for (size_t fi = 0; fi < ArraySize(kFlags); ++fi)
      if (fsi & (1ull << fi))
        flag_set += kFlags[fi];
    result.push_back(flag_set);
  }
  return result;
}

TYPED_TEST_P(TypedFormatConvertTest, AllIntsWithFlags) {
  typedef TypeParam T;
  typedef typename std::make_unsigned<T>::type UnsignedT;
  using remove_volatile_t = typename std::remove_volatile<T>::type;
  const T kMin = std::numeric_limits<remove_volatile_t>::min();
  const T kMax = std::numeric_limits<remove_volatile_t>::max();
  const T kVals[] = {
      remove_volatile_t(1),
      remove_volatile_t(2),
      remove_volatile_t(3),
      remove_volatile_t(123),
      remove_volatile_t(-1),
      remove_volatile_t(-2),
      remove_volatile_t(-3),
      remove_volatile_t(-123),
      remove_volatile_t(0),
      kMax - remove_volatile_t(1),
      kMax,
      kMin + remove_volatile_t(1),
      kMin,
  };
  const char kConvChars[] = {'d', 'i', 'u', 'o', 'x', 'X'};
  const std::string kWid[] = {"", "4", "10"};
  const std::string kPrec[] = {"", ".", ".0", ".4", ".10"};

  const std::vector<std::string> flag_sets = AllFlagCombinations();

  for (size_t vi = 0; vi < ArraySize(kVals); ++vi) {
    const T val = kVals[vi];
    SCOPED_TRACE(Esc(val));
    const FormatArgImpl args[] = {FormatArgImpl(val)};
    for (size_t ci = 0; ci < ArraySize(kConvChars); ++ci) {
      const char conv_char = kConvChars[ci];
      for (size_t fsi = 0; fsi < flag_sets.size(); ++fsi) {
        const std::string &flag_set = flag_sets[fsi];
        for (size_t wi = 0; wi < ArraySize(kWid); ++wi) {
          const std::string &wid = kWid[wi];
          for (size_t pi = 0; pi < ArraySize(kPrec); ++pi) {
            const std::string &prec = kPrec[pi];

            const bool is_signed_conv = (conv_char == 'd' || conv_char == 'i');
            const bool is_unsigned_to_signed =
                !std::is_signed<T>::value && is_signed_conv;
            // Don't consider sign-related flags '+' and ' ' when doing
            // unsigned to signed conversions.
            if (is_unsigned_to_signed &&
                flag_set.find_first_of("+ ") != std::string::npos) {
              continue;
            }

            std::string new_fmt("%");
            new_fmt += flag_set;
            new_fmt += wid;
            new_fmt += prec;
            // old and new always agree up to here.
            std::string old_fmt = new_fmt;
            new_fmt += conv_char;
            std::string old_result;
            if (is_unsigned_to_signed) {
              // don't expect agreement on unsigned formatted as signed,
              // as printf can't do that conversion properly. For those
              // cases, we do expect agreement with printf with a "%u"
              // and the unsigned equivalent of 'val'.
              UnsignedT uval = val;
              old_fmt += LengthModFor(uval);
              old_fmt += "u";
              old_result = StrPrint(old_fmt.c_str(), uval);
            } else {
              old_fmt += LengthModFor(val);
              old_fmt += conv_char;
              old_result = StrPrint(old_fmt.c_str(), val);
            }

            SCOPED_TRACE(std::string() + " old_fmt: \"" + old_fmt +
                         "\"'"
                         " new_fmt: \"" +
                         new_fmt + "\"");
            UntypedFormatSpecImpl format(new_fmt);
            EXPECT_EQ(old_result, FormatPack(format, absl::MakeSpan(args)));
          }
        }
      }
    }
  }
}

TYPED_TEST_P(TypedFormatConvertTest, Char) {
  typedef TypeParam T;
  using remove_volatile_t = typename std::remove_volatile<T>::type;
  static const T kMin = std::numeric_limits<remove_volatile_t>::min();
  static const T kMax = std::numeric_limits<remove_volatile_t>::max();
  T kVals[] = {
    remove_volatile_t(1), remove_volatile_t(2), remove_volatile_t(10),
    remove_volatile_t(-1), remove_volatile_t(-2), remove_volatile_t(-10),
    remove_volatile_t(0),
    kMin + remove_volatile_t(1), kMin,
    kMax - remove_volatile_t(1), kMax
  };
  for (const T &c : kVals) {
    const FormatArgImpl args[] = {FormatArgImpl(c)};
    UntypedFormatSpecImpl format("%c");
    EXPECT_EQ(StrPrint("%c", c), FormatPack(format, absl::MakeSpan(args)));
  }
}

REGISTER_TYPED_TEST_CASE_P(TypedFormatConvertTest, AllIntsWithFlags, Char);

typedef ::testing::Types<
    int, unsigned, volatile int,
    short, unsigned short,
    long, unsigned long,
    long long, unsigned long long,
    signed char, unsigned char, char>
    AllIntTypes;
INSTANTIATE_TYPED_TEST_CASE_P(TypedFormatConvertTestWithAllIntTypes,
                              TypedFormatConvertTest, AllIntTypes);
TEST_F(FormatConvertTest, VectorBool) {
  // Make sure vector<bool>'s values behave as bools.
  std::vector<bool> v = {true, false};
  const std::vector<bool> cv = {true, false};
  EXPECT_EQ("1,0,1,0",
            FormatPack(UntypedFormatSpecImpl("%d,%d,%d,%d"),
                       absl::Span<const FormatArgImpl>(
                           {FormatArgImpl(v[0]), FormatArgImpl(v[1]),
                            FormatArgImpl(cv[0]), FormatArgImpl(cv[1])})));
}


TEST_F(FormatConvertTest, Int128) {
  absl::int128 positive = static_cast<absl::int128>(0x1234567890abcdef) * 1979;
  absl::int128 negative = -positive;
  absl::int128 max = absl::Int128Max(), min = absl::Int128Min();
  const FormatArgImpl args[] = {FormatArgImpl(positive),
                                FormatArgImpl(negative), FormatArgImpl(max),
                                FormatArgImpl(min)};

  struct Case {
    const char* format;
    const char* expected;
  } cases[] = {
      {"%1$d", "2595989796776606496405"},
      {"%1$30d", "        2595989796776606496405"},
      {"%1$-30d", "2595989796776606496405        "},
      {"%1$u", "2595989796776606496405"},
      {"%1$x", "8cba9876066020f695"},
      {"%2$d", "-2595989796776606496405"},
      {"%2$30d", "       -2595989796776606496405"},
      {"%2$-30d", "-2595989796776606496405       "},
      {"%2$u", "340282366920938460867384810655161715051"},
      {"%2$x", "ffffffffffffff73456789f99fdf096b"},
      {"%3$d", "170141183460469231731687303715884105727"},
      {"%3$u", "170141183460469231731687303715884105727"},
      {"%3$x", "7fffffffffffffffffffffffffffffff"},
      {"%4$d", "-170141183460469231731687303715884105728"},
      {"%4$x", "80000000000000000000000000000000"},
  };

  for (auto c : cases) {
    UntypedFormatSpecImpl format(c.format);
    EXPECT_EQ(c.expected, FormatPack(format, absl::MakeSpan(args)));
  }
}

TEST_F(FormatConvertTest, Uint128) {
  absl::uint128 v = static_cast<absl::uint128>(0x1234567890abcdef) * 1979;
  absl::uint128 max = absl::Uint128Max();
  const FormatArgImpl args[] = {FormatArgImpl(v), FormatArgImpl(max)};

  struct Case {
    const char* format;
    const char* expected;
  } cases[] = {
      {"%1$d", "2595989796776606496405"},
      {"%1$30d", "        2595989796776606496405"},
      {"%1$-30d", "2595989796776606496405        "},
      {"%1$u", "2595989796776606496405"},
      {"%1$x", "8cba9876066020f695"},
      {"%2$d", "340282366920938463463374607431768211455"},
      {"%2$u", "340282366920938463463374607431768211455"},
      {"%2$x", "ffffffffffffffffffffffffffffffff"},
  };

  for (auto c : cases) {
    UntypedFormatSpecImpl format(c.format);
    EXPECT_EQ(c.expected, FormatPack(format, absl::MakeSpan(args)));
  }
}

TEST_F(FormatConvertTest, Float) {
#ifdef _MSC_VER
  // MSVC has a different rounding policy than us so we can't test our
  // implementation against the native one there.
  return;
#endif  // _MSC_VER

  const char *const kFormats[] = {
      "%",  "%.3",  "%8.5",   "%9",   "%.60", "%.30",   "%03",    "%+",
      "% ", "%-10", "%#15.3", "%#.0", "%.0",  "%1$*2$", "%1$.*2$"};

  std::vector<double> doubles = {0.0,
                                 -0.0,
                                 .99999999999999,
                                 99999999999999.,
                                 std::numeric_limits<double>::max(),
                                 -std::numeric_limits<double>::max(),
                                 std::numeric_limits<double>::min(),
                                 -std::numeric_limits<double>::min(),
                                 std::numeric_limits<double>::lowest(),
                                 -std::numeric_limits<double>::lowest(),
                                 std::numeric_limits<double>::epsilon(),
                                 std::numeric_limits<double>::epsilon() + 1,
                                 std::numeric_limits<double>::infinity(),
                                 -std::numeric_limits<double>::infinity()};

#ifndef __APPLE__
  // Apple formats NaN differently (+nan) vs. (nan)
  doubles.push_back(std::nan(""));
#endif

  // Some regression tests.
  doubles.push_back(0.99999999999999989);

  if (std::numeric_limits<double>::has_denorm != std::denorm_absent) {
    doubles.push_back(std::numeric_limits<double>::denorm_min());
    doubles.push_back(-std::numeric_limits<double>::denorm_min());
  }

  for (double base :
       {1., 12., 123., 1234., 12345., 123456., 1234567., 12345678., 123456789.,
        1234567890., 12345678901., 123456789012., 1234567890123.}) {
    for (int exp = -123; exp <= 123; ++exp) {
      for (int sign : {1, -1}) {
        doubles.push_back(sign * std::ldexp(base, exp));
      }
    }
  }

  for (const char *fmt : kFormats) {
    for (char f : {'f', 'F',  //
                   'g', 'G',  //
                   'a', 'A',  //
                   'e', 'E'}) {
      std::string fmt_str = std::string(fmt) + f;
      for (double d : doubles) {
        int i = -10;
        FormatArgImpl args[2] = {FormatArgImpl(d), FormatArgImpl(i)};
        UntypedFormatSpecImpl format(fmt_str);
        // We use ASSERT_EQ here because failures are usually correlated and a
        // bug would print way too many failed expectations causing the test to
        // time out.
        ASSERT_EQ(StrPrint(fmt_str.c_str(), d, i),
                  FormatPack(format, absl::MakeSpan(args)))
            << fmt_str << " " << StrPrint("%.18g", d) << " "
            << StrPrint("%.999f", d);
      }
    }
  }
}

TEST_F(FormatConvertTest, LongDouble) {
  const char *const kFormats[] = {"%",    "%.3", "%8.5", "%9",
                                  "%.60", "%+",  "% ",   "%-10"};

  // This value is not representable in double, but it is in long double that
  // uses the extended format.
  // This is to verify that we are not truncating the value mistakenly through a
  // double.
  long double very_precise = 10000000000000000.25L;

  std::vector<long double> doubles = {
      0.0,
      -0.0,
      very_precise,
      1 / very_precise,
      std::numeric_limits<long double>::max(),
      -std::numeric_limits<long double>::max(),
      std::numeric_limits<long double>::min(),
      -std::numeric_limits<long double>::min(),
      std::numeric_limits<long double>::infinity(),
      -std::numeric_limits<long double>::infinity()};

  for (const char *fmt : kFormats) {
    for (char f : {'f', 'F',  //
                   'g', 'G',  //
                   'a', 'A',  //
                   'e', 'E'}) {
      std::string fmt_str = std::string(fmt) + 'L' + f;
      for (auto d : doubles) {
        FormatArgImpl arg(d);
        UntypedFormatSpecImpl format(fmt_str);
        // We use ASSERT_EQ here because failures are usually correlated and a
        // bug would print way too many failed expectations causing the test to
        // time out.
        ASSERT_EQ(StrPrint(fmt_str.c_str(), d),
                  FormatPack(format, {&arg, 1}))
            << fmt_str << " " << StrPrint("%.18Lg", d) << " "
            << StrPrint("%.999Lf", d);
      }
    }
  }
}

TEST_F(FormatConvertTest, IntAsFloat) {
  const int kMin = std::numeric_limits<int>::min();
  const int kMax = std::numeric_limits<int>::max();
  const int ia[] = {
    1, 2, 3, 123,
    -1, -2, -3, -123,
    0, kMax - 1, kMax, kMin + 1, kMin };
  for (const int fx : ia) {
    SCOPED_TRACE(fx);
    const FormatArgImpl args[] = {FormatArgImpl(fx)};
    struct Expectation {
      int line;
      std::string out;
      const char *fmt;
    };
    const double dx = static_cast<double>(fx);
    const Expectation kExpect[] = {
      { __LINE__, StrPrint("%f", dx), "%f" },
      { __LINE__, StrPrint("%12f", dx), "%12f" },
      { __LINE__, StrPrint("%.12f", dx), "%.12f" },
      { __LINE__, StrPrint("%12a", dx), "%12a" },
      { __LINE__, StrPrint("%.12a", dx), "%.12a" },
    };
    for (const Expectation &e : kExpect) {
      SCOPED_TRACE(e.line);
      SCOPED_TRACE(e.fmt);
      UntypedFormatSpecImpl format(e.fmt);
      EXPECT_EQ(e.out, FormatPack(format, absl::MakeSpan(args)));
    }
  }
}

template <typename T>
bool FormatFails(const char* test_format, T value) {
  std::string format_string = std::string("<<") + test_format + ">>";
  UntypedFormatSpecImpl format(format_string);

  int one = 1;
  const FormatArgImpl args[] = {FormatArgImpl(value), FormatArgImpl(one)};
  EXPECT_EQ(FormatPack(format, absl::MakeSpan(args)), "")
      << "format=" << test_format << " value=" << value;
  return FormatPack(format, absl::MakeSpan(args)).empty();
}

TEST_F(FormatConvertTest, ExpectedFailures) {
  // Int input
  EXPECT_TRUE(FormatFails("%p", 1));
  EXPECT_TRUE(FormatFails("%s", 1));
  EXPECT_TRUE(FormatFails("%n", 1));

  // Double input
  EXPECT_TRUE(FormatFails("%p", 1.));
  EXPECT_TRUE(FormatFails("%s", 1.));
  EXPECT_TRUE(FormatFails("%n", 1.));
  EXPECT_TRUE(FormatFails("%c", 1.));
  EXPECT_TRUE(FormatFails("%d", 1.));
  EXPECT_TRUE(FormatFails("%x", 1.));
  EXPECT_TRUE(FormatFails("%*d", 1.));

  // String input
  EXPECT_TRUE(FormatFails("%n", ""));
  EXPECT_TRUE(FormatFails("%c", ""));
  EXPECT_TRUE(FormatFails("%d", ""));
  EXPECT_TRUE(FormatFails("%x", ""));
  EXPECT_TRUE(FormatFails("%f", ""));
  EXPECT_TRUE(FormatFails("%*d", ""));
}

}  // namespace
}  // namespace str_format_internal
}  // namespace absl