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17//
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28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30// Google Test - The Google C++ Testing and Mocking Framework
31//
32// This file implements a universal value printer that can print a
33// value of any type T:
34//
35// void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr);
36//
37// A user can teach this function how to print a class type T by
38// defining either operator<<() or PrintTo() in the namespace that
39// defines T. More specifically, the FIRST defined function in the
40// following list will be used (assuming T is defined in namespace
41// foo):
42//
43// 1. foo::PrintTo(const T&, ostream*)
44// 2. operator<<(ostream&, const T&) defined in either foo or the
45// global namespace.
46// * Prefer AbslStringify(..) to operator<<(..), per https://abseil.io/tips/215.
47// * Define foo::PrintTo(..) if the type already has AbslStringify(..), but an
48// alternative presentation in test results is of interest.
49//
50// However if T is an STL-style container then it is printed element-wise
51// unless foo::PrintTo(const T&, ostream*) is defined. Note that
52// operator<<() is ignored for container types.
53//
54// If none of the above is defined, it will print the debug string of
55// the value if it is a protocol buffer, or print the raw bytes in the
56// value otherwise.
57//
58// To aid debugging: when T is a reference type, the address of the
59// value is also printed; when T is a (const) char pointer, both the
60// pointer value and the NUL-terminated string it points to are
61// printed.
62//
63// We also provide some convenient wrappers:
64//
65// // Prints a value to a string. For a (const or not) char
66// // pointer, the NUL-terminated string (but not the pointer) is
67// // printed.
68// std::string ::testing::PrintToString(const T& value);
69//
70// // Prints a value tersely: for a reference type, the referenced
71// // value (but not the address) is printed; for a (const or not) char
72// // pointer, the NUL-terminated string (but not the pointer) is
73// // printed.
74// void ::testing::internal::UniversalTersePrint(const T& value, ostream*);
75//
76// // Prints value using the type inferred by the compiler. The difference
77// // from UniversalTersePrint() is that this function prints both the
78// // pointer and the NUL-terminated string for a (const or not) char pointer.
79// void ::testing::internal::UniversalPrint(const T& value, ostream*);
80//
81// // Prints the fields of a tuple tersely to a string vector, one
82// // element for each field. Tuple support must be enabled in
83// // gtest-port.h.
84// std::vector<string> UniversalTersePrintTupleFieldsToStrings(
85// const Tuple& value);
86//
87// Known limitation:
88//
89// The print primitives print the elements of an STL-style container
90// using the compiler-inferred type of *iter where iter is a
91// const_iterator of the container. When const_iterator is an input
92// iterator but not a forward iterator, this inferred type may not
93// match value_type, and the print output may be incorrect. In
94// practice, this is rarely a problem as for most containers
95// const_iterator is a forward iterator. We'll fix this if there's an
96// actual need for it. Note that this fix cannot rely on value_type
97// being defined as many user-defined container types don't have
98// value_type.
99
100// IWYU pragma: private, include "gtest/gtest.h"
101// IWYU pragma: friend gtest/.*
102// IWYU pragma: friend gmock/.*
103
104#ifndef GOOGLETEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
105#define GOOGLETEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
106
107#include <functional>
108#include <memory>
109#include <ostream> // NOLINT
110#include <sstream>
111#include <string>
112#include <tuple>
113#include <type_traits>
114#include <typeinfo>
115#include <utility>
116#include <vector>
117
118#ifdef GTEST_HAS_ABSL
119#include "absl/strings/internal/has_absl_stringify.h"
120#include "absl/strings/str_cat.h"
121#endif // GTEST_HAS_ABSL
122#include "gtest/internal/gtest-internal.h"
123#include "gtest/internal/gtest-port.h"
124
125namespace testing {
126
127// Definitions in the internal* namespaces are subject to change without notice.
128// DO NOT USE THEM IN USER CODE!
129namespace internal {
130
131template <typename T>
132void UniversalPrint(const T& value, ::std::ostream* os);
133
134// Used to print an STL-style container when the user doesn't define
135// a PrintTo() for it.
136struct ContainerPrinter {
137 template <typename T,
138 typename = typename std::enable_if<
139 (sizeof(IsContainerTest<T>(0)) == sizeof(IsContainer)) &&
140 !IsRecursiveContainer<T>::value>::type>
141 static void PrintValue(const T& container, std::ostream* os) {
142 const size_t kMaxCount = 32; // The maximum number of elements to print.
143 *os << '{';
144 size_t count = 0;
145 for (auto&& elem : container) {
146 if (count > 0) {
147 *os << ',';
148 if (count == kMaxCount) { // Enough has been printed.
149 *os << " ...";
150 break;
151 }
152 }
153 *os << ' ';
154 // We cannot call PrintTo(elem, os) here as PrintTo() doesn't
155 // handle `elem` being a native array.
156 internal::UniversalPrint(elem, os);
157 ++count;
158 }
159
160 if (count > 0) {
161 *os << ' ';
162 }
163 *os << '}';
164 }
165};
166
167// Used to print a pointer that is neither a char pointer nor a member
168// pointer, when the user doesn't define PrintTo() for it. (A member
169// variable pointer or member function pointer doesn't really point to
170// a location in the address space. Their representation is
171// implementation-defined. Therefore they will be printed as raw
172// bytes.)
173struct FunctionPointerPrinter {
174 template <typename T, typename = typename std::enable_if<
175 std::is_function<T>::value>::type>
176 static void PrintValue(T* p, ::std::ostream* os) {
177 if (p == nullptr) {
178 *os << "NULL";
179 } else {
180 // T is a function type, so '*os << p' doesn't do what we want
181 // (it just prints p as bool). We want to print p as a const
182 // void*.
183 *os << reinterpret_cast<const void*>(p);
184 }
185 }
186};
187
188struct PointerPrinter {
189 template <typename T>
190 static void PrintValue(T* p, ::std::ostream* os) {
191 if (p == nullptr) {
192 *os << "NULL";
193 } else {
194 // T is not a function type. We just call << to print p,
195 // relying on ADL to pick up user-defined << for their pointer
196 // types, if any.
197 *os << p;
198 }
199 }
200};
201
202namespace internal_stream_operator_without_lexical_name_lookup {
203
204// The presence of an operator<< here will terminate lexical scope lookup
205// straight away (even though it cannot be a match because of its argument
206// types). Thus, the two operator<< calls in StreamPrinter will find only ADL
207// candidates.
208struct LookupBlocker {};
209void operator<<(LookupBlocker, LookupBlocker);
210
211struct StreamPrinter {
212 template <typename T,
213 // Don't accept member pointers here. We'd print them via implicit
214 // conversion to bool, which isn't useful.
215 typename = typename std::enable_if<
216 !std::is_member_pointer<T>::value>::type>
217 // Only accept types for which we can find a streaming operator via
218 // ADL (possibly involving implicit conversions).
219 // (Use SFINAE via return type, because it seems GCC < 12 doesn't handle name
220 // lookup properly when we do it in the template parameter list.)
221 static auto PrintValue(const T& value, ::std::ostream* os)
222 -> decltype((void)(*os << value)) {
223 // Call streaming operator found by ADL, possibly with implicit conversions
224 // of the arguments.
225 *os << value;
226 }
227};
228
229} // namespace internal_stream_operator_without_lexical_name_lookup
230
231struct ProtobufPrinter {
232 // We print a protobuf using its ShortDebugString() when the string
233 // doesn't exceed this many characters; otherwise we print it using
234 // DebugString() for better readability.
235 static const size_t kProtobufOneLinerMaxLength = 50;
236
237 template <typename T,
238 typename = typename std::enable_if<
239 internal::HasDebugStringAndShortDebugString<T>::value>::type>
240 static void PrintValue(const T& value, ::std::ostream* os) {
241 std::string pretty_str = value.ShortDebugString();
242 if (pretty_str.length() > kProtobufOneLinerMaxLength) {
243 pretty_str = "\n" + value.DebugString();
244 }
245 *os << ("<" + pretty_str + ">");
246 }
247};
248
249struct ConvertibleToIntegerPrinter {
250 // Since T has no << operator or PrintTo() but can be implicitly
251 // converted to BiggestInt, we print it as a BiggestInt.
252 //
253 // Most likely T is an enum type (either named or unnamed), in which
254 // case printing it as an integer is the desired behavior. In case
255 // T is not an enum, printing it as an integer is the best we can do
256 // given that it has no user-defined printer.
257 static void PrintValue(internal::BiggestInt value, ::std::ostream* os) {
258 *os << value;
259 }
260};
261
262struct ConvertibleToStringViewPrinter {
263#if GTEST_INTERNAL_HAS_STRING_VIEW
264 static void PrintValue(internal::StringView value, ::std::ostream* os) {
265 internal::UniversalPrint(value, os);
266 }
267#endif
268};
269
270#ifdef GTEST_HAS_ABSL
271struct ConvertibleToAbslStringifyPrinter {
272 template <
273 typename T,
274 typename = typename std::enable_if<
275 absl::strings_internal::HasAbslStringify<T>::value>::type> // NOLINT
276 static void PrintValue(const T& value, ::std::ostream* os) {
277 *os << absl::StrCat(value);
278 }
279};
280#endif // GTEST_HAS_ABSL
281
282// Prints the given number of bytes in the given object to the given
283// ostream.
284GTEST_API_ void PrintBytesInObjectTo(const unsigned char* obj_bytes,
285 size_t count, ::std::ostream* os);
286struct RawBytesPrinter {
287 // SFINAE on `sizeof` to make sure we have a complete type.
288 template <typename T, size_t = sizeof(T)>
289 static void PrintValue(const T& value, ::std::ostream* os) {
290 PrintBytesInObjectTo(
291 obj_bytes: static_cast<const unsigned char*>(
292 // Load bearing cast to void* to support iOS
293 reinterpret_cast<const void*>(std::addressof(value))),
294 count: sizeof(value), os);
295 }
296};
297
298struct FallbackPrinter {
299 template <typename T>
300 static void PrintValue(const T&, ::std::ostream* os) {
301 *os << "(incomplete type)";
302 }
303};
304
305// Try every printer in order and return the first one that works.
306template <typename T, typename E, typename Printer, typename... Printers>
307struct FindFirstPrinter : FindFirstPrinter<T, E, Printers...> {};
308
309template <typename T, typename Printer, typename... Printers>
310struct FindFirstPrinter<
311 T, decltype(Printer::PrintValue(std::declval<const T&>(), nullptr)),
312 Printer, Printers...> {
313 using type = Printer;
314};
315
316// Select the best printer in the following order:
317// - Print containers (they have begin/end/etc).
318// - Print function pointers.
319// - Print object pointers.
320// - Print protocol buffers.
321// - Use the stream operator, if available.
322// - Print types convertible to BiggestInt.
323// - Print types convertible to StringView, if available.
324// - Fallback to printing the raw bytes of the object.
325template <typename T>
326void PrintWithFallback(const T& value, ::std::ostream* os) {
327 using Printer = typename FindFirstPrinter<
328 T, void, ContainerPrinter, FunctionPointerPrinter, PointerPrinter,
329 ProtobufPrinter,
330#ifdef GTEST_HAS_ABSL
331 ConvertibleToAbslStringifyPrinter,
332#endif // GTEST_HAS_ABSL
333 internal_stream_operator_without_lexical_name_lookup::StreamPrinter,
334 ConvertibleToIntegerPrinter, ConvertibleToStringViewPrinter,
335 RawBytesPrinter, FallbackPrinter>::type;
336 Printer::PrintValue(value, os);
337}
338
339// FormatForComparison<ToPrint, OtherOperand>::Format(value) formats a
340// value of type ToPrint that is an operand of a comparison assertion
341// (e.g. ASSERT_EQ). OtherOperand is the type of the other operand in
342// the comparison, and is used to help determine the best way to
343// format the value. In particular, when the value is a C string
344// (char pointer) and the other operand is an STL string object, we
345// want to format the C string as a string, since we know it is
346// compared by value with the string object. If the value is a char
347// pointer but the other operand is not an STL string object, we don't
348// know whether the pointer is supposed to point to a NUL-terminated
349// string, and thus want to print it as a pointer to be safe.
350//
351// INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM.
352
353// The default case.
354template <typename ToPrint, typename OtherOperand>
355class FormatForComparison {
356 public:
357 static ::std::string Format(const ToPrint& value) {
358 return ::testing::PrintToString(value);
359 }
360};
361
362// Array.
363template <typename ToPrint, size_t N, typename OtherOperand>
364class FormatForComparison<ToPrint[N], OtherOperand> {
365 public:
366 static ::std::string Format(const ToPrint* value) {
367 return FormatForComparison<const ToPrint*, OtherOperand>::Format(value);
368 }
369};
370
371// By default, print C string as pointers to be safe, as we don't know
372// whether they actually point to a NUL-terminated string.
373
374#define GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(CharType) \
375 template <typename OtherOperand> \
376 class FormatForComparison<CharType*, OtherOperand> { \
377 public: \
378 static ::std::string Format(CharType* value) { \
379 return ::testing::PrintToString(static_cast<const void*>(value)); \
380 } \
381 }
382
383GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char);
384GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char);
385GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(wchar_t);
386GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const wchar_t);
387#ifdef __cpp_lib_char8_t
388GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char8_t);
389GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char8_t);
390#endif
391GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char16_t);
392GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char16_t);
393GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char32_t);
394GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char32_t);
395
396#undef GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_
397
398// If a C string is compared with an STL string object, we know it's meant
399// to point to a NUL-terminated string, and thus can print it as a string.
400
401#define GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(CharType, OtherStringType) \
402 template <> \
403 class FormatForComparison<CharType*, OtherStringType> { \
404 public: \
405 static ::std::string Format(CharType* value) { \
406 return ::testing::PrintToString(value); \
407 } \
408 }
409
410GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char, ::std::string);
411GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char, ::std::string);
412#ifdef __cpp_lib_char8_t
413GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char8_t, ::std::u8string);
414GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char8_t, ::std::u8string);
415#endif
416GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char16_t, ::std::u16string);
417GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char16_t, ::std::u16string);
418GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char32_t, ::std::u32string);
419GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char32_t, ::std::u32string);
420
421#if GTEST_HAS_STD_WSTRING
422GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(wchar_t, ::std::wstring);
423GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const wchar_t, ::std::wstring);
424#endif
425
426#undef GTEST_IMPL_FORMAT_C_STRING_AS_STRING_
427
428// Formats a comparison assertion (e.g. ASSERT_EQ, EXPECT_LT, and etc)
429// operand to be used in a failure message. The type (but not value)
430// of the other operand may affect the format. This allows us to
431// print a char* as a raw pointer when it is compared against another
432// char* or void*, and print it as a C string when it is compared
433// against an std::string object, for example.
434//
435// INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM.
436template <typename T1, typename T2>
437std::string FormatForComparisonFailureMessage(const T1& value,
438 const T2& /* other_operand */) {
439 return FormatForComparison<T1, T2>::Format(value);
440}
441
442// UniversalPrinter<T>::Print(value, ostream_ptr) prints the given
443// value to the given ostream. The caller must ensure that
444// 'ostream_ptr' is not NULL, or the behavior is undefined.
445//
446// We define UniversalPrinter as a class template (as opposed to a
447// function template), as we need to partially specialize it for
448// reference types, which cannot be done with function templates.
449template <typename T>
450class UniversalPrinter;
451
452// Prints the given value using the << operator if it has one;
453// otherwise prints the bytes in it. This is what
454// UniversalPrinter<T>::Print() does when PrintTo() is not specialized
455// or overloaded for type T.
456//
457// A user can override this behavior for a class type Foo by defining
458// an overload of PrintTo() in the namespace where Foo is defined. We
459// give the user this option as sometimes defining a << operator for
460// Foo is not desirable (e.g. the coding style may prevent doing it,
461// or there is already a << operator but it doesn't do what the user
462// wants).
463template <typename T>
464void PrintTo(const T& value, ::std::ostream* os) {
465 internal::PrintWithFallback(value, os);
466}
467
468// The following list of PrintTo() overloads tells
469// UniversalPrinter<T>::Print() how to print standard types (built-in
470// types, strings, plain arrays, and pointers).
471
472// Overloads for various char types.
473GTEST_API_ void PrintTo(unsigned char c, ::std::ostream* os);
474GTEST_API_ void PrintTo(signed char c, ::std::ostream* os);
475inline void PrintTo(char c, ::std::ostream* os) {
476 // When printing a plain char, we always treat it as unsigned. This
477 // way, the output won't be affected by whether the compiler thinks
478 // char is signed or not.
479 PrintTo(c: static_cast<unsigned char>(c), os);
480}
481
482// Overloads for other simple built-in types.
483inline void PrintTo(bool x, ::std::ostream* os) {
484 *os << (x ? "true" : "false");
485}
486
487// Overload for wchar_t type.
488// Prints a wchar_t as a symbol if it is printable or as its internal
489// code otherwise and also as its decimal code (except for L'\0').
490// The L'\0' char is printed as "L'\\0'". The decimal code is printed
491// as signed integer when wchar_t is implemented by the compiler
492// as a signed type and is printed as an unsigned integer when wchar_t
493// is implemented as an unsigned type.
494GTEST_API_ void PrintTo(wchar_t wc, ::std::ostream* os);
495
496GTEST_API_ void PrintTo(char32_t c, ::std::ostream* os);
497inline void PrintTo(char16_t c, ::std::ostream* os) {
498 PrintTo(c: ImplicitCast_<char32_t>(x: c), os);
499}
500#ifdef __cpp_lib_char8_t
501inline void PrintTo(char8_t c, ::std::ostream* os) {
502 PrintTo(ImplicitCast_<char32_t>(c), os);
503}
504#endif
505
506// gcc/clang __{u,}int128_t
507#if defined(__SIZEOF_INT128__)
508GTEST_API_ void PrintTo(__uint128_t v, ::std::ostream* os);
509GTEST_API_ void PrintTo(__int128_t v, ::std::ostream* os);
510#endif // __SIZEOF_INT128__
511
512// The default resolution used to print floating-point values uses only
513// 6 digits, which can be confusing if a test compares two values whose
514// difference lies in the 7th digit. So we'd like to print out numbers
515// in full precision.
516// However if the value is something simple like 1.1, full will print a
517// long string like 1.100000001 due to floating-point numbers not using
518// a base of 10. This routiune returns an appropriate resolution for a
519// given floating-point number, that is, 6 if it will be accurate, or a
520// max_digits10 value (full precision) if it won't, for values between
521// 0.0001 and one million.
522// It does this by computing what those digits would be (by multiplying
523// by an appropriate power of 10), then dividing by that power again to
524// see if gets the original value back.
525// A similar algorithm applies for values larger than one million; note
526// that for those values, we must divide to get a six-digit number, and
527// then multiply to possibly get the original value again.
528template <typename FloatType>
529int AppropriateResolution(FloatType val) {
530 int full = std::numeric_limits<FloatType>::max_digits10;
531 if (val < 0) val = -val;
532
533 if (val < 1000000) {
534 FloatType mulfor6 = 1e10;
535 if (val >= 100000.0) { // 100,000 to 999,999
536 mulfor6 = 1.0;
537 } else if (val >= 10000.0) {
538 mulfor6 = 1e1;
539 } else if (val >= 1000.0) {
540 mulfor6 = 1e2;
541 } else if (val >= 100.0) {
542 mulfor6 = 1e3;
543 } else if (val >= 10.0) {
544 mulfor6 = 1e4;
545 } else if (val >= 1.0) {
546 mulfor6 = 1e5;
547 } else if (val >= 0.1) {
548 mulfor6 = 1e6;
549 } else if (val >= 0.01) {
550 mulfor6 = 1e7;
551 } else if (val >= 0.001) {
552 mulfor6 = 1e8;
553 } else if (val >= 0.0001) {
554 mulfor6 = 1e9;
555 }
556 if (static_cast<FloatType>(static_cast<int32_t>(val * mulfor6 + 0.5)) /
557 mulfor6 ==
558 val)
559 return 6;
560 } else if (val < 1e10) {
561 FloatType divfor6 = 1.0;
562 if (val >= 1e9) { // 1,000,000,000 to 9,999,999,999
563 divfor6 = 10000;
564 } else if (val >= 1e8) { // 100,000,000 to 999,999,999
565 divfor6 = 1000;
566 } else if (val >= 1e7) { // 10,000,000 to 99,999,999
567 divfor6 = 100;
568 } else if (val >= 1e6) { // 1,000,000 to 9,999,999
569 divfor6 = 10;
570 }
571 if (static_cast<FloatType>(static_cast<int32_t>(val / divfor6 + 0.5)) *
572 divfor6 ==
573 val)
574 return 6;
575 }
576 return full;
577}
578
579inline void PrintTo(float f, ::std::ostream* os) {
580 auto old_precision = os->precision();
581 os->precision(prec: AppropriateResolution(val: f));
582 *os << f;
583 os->precision(prec: old_precision);
584}
585
586inline void PrintTo(double d, ::std::ostream* os) {
587 auto old_precision = os->precision();
588 os->precision(prec: AppropriateResolution(val: d));
589 *os << d;
590 os->precision(prec: old_precision);
591}
592
593// Overloads for C strings.
594GTEST_API_ void PrintTo(const char* s, ::std::ostream* os);
595inline void PrintTo(char* s, ::std::ostream* os) {
596 PrintTo(s: ImplicitCast_<const char*>(x: s), os);
597}
598
599// signed/unsigned char is often used for representing binary data, so
600// we print pointers to it as void* to be safe.
601inline void PrintTo(const signed char* s, ::std::ostream* os) {
602 PrintTo(value: ImplicitCast_<const void*>(x: s), os);
603}
604inline void PrintTo(signed char* s, ::std::ostream* os) {
605 PrintTo(value: ImplicitCast_<const void*>(x: s), os);
606}
607inline void PrintTo(const unsigned char* s, ::std::ostream* os) {
608 PrintTo(value: ImplicitCast_<const void*>(x: s), os);
609}
610inline void PrintTo(unsigned char* s, ::std::ostream* os) {
611 PrintTo(value: ImplicitCast_<const void*>(x: s), os);
612}
613#ifdef __cpp_lib_char8_t
614// Overloads for u8 strings.
615GTEST_API_ void PrintTo(const char8_t* s, ::std::ostream* os);
616inline void PrintTo(char8_t* s, ::std::ostream* os) {
617 PrintTo(ImplicitCast_<const char8_t*>(s), os);
618}
619#endif
620// Overloads for u16 strings.
621GTEST_API_ void PrintTo(const char16_t* s, ::std::ostream* os);
622inline void PrintTo(char16_t* s, ::std::ostream* os) {
623 PrintTo(s: ImplicitCast_<const char16_t*>(x: s), os);
624}
625// Overloads for u32 strings.
626GTEST_API_ void PrintTo(const char32_t* s, ::std::ostream* os);
627inline void PrintTo(char32_t* s, ::std::ostream* os) {
628 PrintTo(s: ImplicitCast_<const char32_t*>(x: s), os);
629}
630
631// MSVC can be configured to define wchar_t as a typedef of unsigned
632// short. It defines _NATIVE_WCHAR_T_DEFINED when wchar_t is a native
633// type. When wchar_t is a typedef, defining an overload for const
634// wchar_t* would cause unsigned short* be printed as a wide string,
635// possibly causing invalid memory accesses.
636#if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
637// Overloads for wide C strings
638GTEST_API_ void PrintTo(const wchar_t* s, ::std::ostream* os);
639inline void PrintTo(wchar_t* s, ::std::ostream* os) {
640 PrintTo(s: ImplicitCast_<const wchar_t*>(x: s), os);
641}
642#endif
643
644// Overload for C arrays. Multi-dimensional arrays are printed
645// properly.
646
647// Prints the given number of elements in an array, without printing
648// the curly braces.
649template <typename T>
650void PrintRawArrayTo(const T a[], size_t count, ::std::ostream* os) {
651 UniversalPrint(a[0], os);
652 for (size_t i = 1; i != count; i++) {
653 *os << ", ";
654 UniversalPrint(a[i], os);
655 }
656}
657
658// Overloads for ::std::string.
659GTEST_API_ void PrintStringTo(const ::std::string& s, ::std::ostream* os);
660inline void PrintTo(const ::std::string& s, ::std::ostream* os) {
661 PrintStringTo(s, os);
662}
663
664// Overloads for ::std::u8string
665#ifdef __cpp_lib_char8_t
666GTEST_API_ void PrintU8StringTo(const ::std::u8string& s, ::std::ostream* os);
667inline void PrintTo(const ::std::u8string& s, ::std::ostream* os) {
668 PrintU8StringTo(s, os);
669}
670#endif
671
672// Overloads for ::std::u16string
673GTEST_API_ void PrintU16StringTo(const ::std::u16string& s, ::std::ostream* os);
674inline void PrintTo(const ::std::u16string& s, ::std::ostream* os) {
675 PrintU16StringTo(s, os);
676}
677
678// Overloads for ::std::u32string
679GTEST_API_ void PrintU32StringTo(const ::std::u32string& s, ::std::ostream* os);
680inline void PrintTo(const ::std::u32string& s, ::std::ostream* os) {
681 PrintU32StringTo(s, os);
682}
683
684// Overloads for ::std::wstring.
685#if GTEST_HAS_STD_WSTRING
686GTEST_API_ void PrintWideStringTo(const ::std::wstring& s, ::std::ostream* os);
687inline void PrintTo(const ::std::wstring& s, ::std::ostream* os) {
688 PrintWideStringTo(s, os);
689}
690#endif // GTEST_HAS_STD_WSTRING
691
692#if GTEST_INTERNAL_HAS_STRING_VIEW
693// Overload for internal::StringView.
694inline void PrintTo(internal::StringView sp, ::std::ostream* os) {
695 PrintTo(s: ::std::string(sp), os);
696}
697#endif // GTEST_INTERNAL_HAS_STRING_VIEW
698
699inline void PrintTo(std::nullptr_t, ::std::ostream* os) { *os << "(nullptr)"; }
700
701#if GTEST_HAS_RTTI
702inline void PrintTo(const std::type_info& info, std::ostream* os) {
703 *os << internal::GetTypeName(type: info);
704}
705#endif // GTEST_HAS_RTTI
706
707template <typename T>
708void PrintTo(std::reference_wrapper<T> ref, ::std::ostream* os) {
709 UniversalPrinter<T&>::Print(ref.get(), os);
710}
711
712inline const void* VoidifyPointer(const void* p) { return p; }
713inline const void* VoidifyPointer(volatile const void* p) {
714 return const_cast<const void*>(p);
715}
716
717template <typename T, typename Ptr>
718void PrintSmartPointer(const Ptr& ptr, std::ostream* os, char) {
719 if (ptr == nullptr) {
720 *os << "(nullptr)";
721 } else {
722 // We can't print the value. Just print the pointer..
723 *os << "(" << (VoidifyPointer)(ptr.get()) << ")";
724 }
725}
726template <typename T, typename Ptr,
727 typename = typename std::enable_if<!std::is_void<T>::value &&
728 !std::is_array<T>::value>::type>
729void PrintSmartPointer(const Ptr& ptr, std::ostream* os, int) {
730 if (ptr == nullptr) {
731 *os << "(nullptr)";
732 } else {
733 *os << "(ptr = " << (VoidifyPointer)(ptr.get()) << ", value = ";
734 UniversalPrinter<T>::Print(*ptr, os);
735 *os << ")";
736 }
737}
738
739template <typename T, typename D>
740void PrintTo(const std::unique_ptr<T, D>& ptr, std::ostream* os) {
741 (PrintSmartPointer<T>)(ptr, os, 0);
742}
743
744template <typename T>
745void PrintTo(const std::shared_ptr<T>& ptr, std::ostream* os) {
746 (PrintSmartPointer<T>)(ptr, os, 0);
747}
748
749// Helper function for printing a tuple. T must be instantiated with
750// a tuple type.
751template <typename T>
752void PrintTupleTo(const T&, std::integral_constant<size_t, 0>,
753 ::std::ostream*) {}
754
755template <typename T, size_t I>
756void PrintTupleTo(const T& t, std::integral_constant<size_t, I>,
757 ::std::ostream* os) {
758 PrintTupleTo(t, std::integral_constant<size_t, I - 1>(), os);
759 GTEST_INTENTIONAL_CONST_COND_PUSH_()
760 if (I > 1) {
761 GTEST_INTENTIONAL_CONST_COND_POP_()
762 *os << ", ";
763 }
764 UniversalPrinter<typename std::tuple_element<I - 1, T>::type>::Print(
765 std::get<I - 1>(t), os);
766}
767
768template <typename... Types>
769void PrintTo(const ::std::tuple<Types...>& t, ::std::ostream* os) {
770 *os << "(";
771 PrintTupleTo(t, std::integral_constant<size_t, sizeof...(Types)>(), os);
772 *os << ")";
773}
774
775// Overload for std::pair.
776template <typename T1, typename T2>
777void PrintTo(const ::std::pair<T1, T2>& value, ::std::ostream* os) {
778 *os << '(';
779 // We cannot use UniversalPrint(value.first, os) here, as T1 may be
780 // a reference type. The same for printing value.second.
781 UniversalPrinter<T1>::Print(value.first, os);
782 *os << ", ";
783 UniversalPrinter<T2>::Print(value.second, os);
784 *os << ')';
785}
786
787// Implements printing a non-reference type T by letting the compiler
788// pick the right overload of PrintTo() for T.
789template <typename T>
790class UniversalPrinter {
791 public:
792 // MSVC warns about adding const to a function type, so we want to
793 // disable the warning.
794 GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180)
795
796 // Note: we deliberately don't call this PrintTo(), as that name
797 // conflicts with ::testing::internal::PrintTo in the body of the
798 // function.
799 static void Print(const T& value, ::std::ostream* os) {
800 // By default, ::testing::internal::PrintTo() is used for printing
801 // the value.
802 //
803 // Thanks to Koenig look-up, if T is a class and has its own
804 // PrintTo() function defined in its namespace, that function will
805 // be visible here. Since it is more specific than the generic ones
806 // in ::testing::internal, it will be picked by the compiler in the
807 // following statement - exactly what we want.
808 PrintTo(value, os);
809 }
810
811 GTEST_DISABLE_MSC_WARNINGS_POP_()
812};
813
814// Remove any const-qualifiers before passing a type to UniversalPrinter.
815template <typename T>
816class UniversalPrinter<const T> : public UniversalPrinter<T> {};
817
818#if GTEST_INTERNAL_HAS_ANY
819
820// Printer for std::any / absl::any
821
822template <>
823class UniversalPrinter<Any> {
824 public:
825 static void Print(const Any& value, ::std::ostream* os) {
826 if (value.has_value()) {
827 *os << "value of type " << GetTypeName(value);
828 } else {
829 *os << "no value";
830 }
831 }
832
833 private:
834 static std::string GetTypeName(const Any& value) {
835#if GTEST_HAS_RTTI
836 return internal::GetTypeName(type: value.type());
837#else
838 static_cast<void>(value); // possibly unused
839 return "<unknown_type>";
840#endif // GTEST_HAS_RTTI
841 }
842};
843
844#endif // GTEST_INTERNAL_HAS_ANY
845
846#if GTEST_INTERNAL_HAS_OPTIONAL
847
848// Printer for std::optional / absl::optional
849
850template <typename T>
851class UniversalPrinter<Optional<T>> {
852 public:
853 static void Print(const Optional<T>& value, ::std::ostream* os) {
854 *os << '(';
855 if (!value) {
856 *os << "nullopt";
857 } else {
858 UniversalPrint(*value, os);
859 }
860 *os << ')';
861 }
862};
863
864template <>
865class UniversalPrinter<decltype(Nullopt())> {
866 public:
867 static void Print(decltype(Nullopt()), ::std::ostream* os) {
868 *os << "(nullopt)";
869 }
870};
871
872#endif // GTEST_INTERNAL_HAS_OPTIONAL
873
874#if GTEST_INTERNAL_HAS_VARIANT
875
876// Printer for std::variant / absl::variant
877
878template <typename... T>
879class UniversalPrinter<Variant<T...>> {
880 public:
881 static void Print(const Variant<T...>& value, ::std::ostream* os) {
882 *os << '(';
883#ifdef GTEST_HAS_ABSL
884 absl::visit(Visitor{os, value.index()}, value);
885#else
886 std::visit(Visitor{os, value.index()}, value);
887#endif // GTEST_HAS_ABSL
888 *os << ')';
889 }
890
891 private:
892 struct Visitor {
893 template <typename U>
894 void operator()(const U& u) const {
895 *os << "'" << GetTypeName<U>() << "(index = " << index
896 << ")' with value ";
897 UniversalPrint(u, os);
898 }
899 ::std::ostream* os;
900 std::size_t index;
901 };
902};
903
904#endif // GTEST_INTERNAL_HAS_VARIANT
905
906// UniversalPrintArray(begin, len, os) prints an array of 'len'
907// elements, starting at address 'begin'.
908template <typename T>
909void UniversalPrintArray(const T* begin, size_t len, ::std::ostream* os) {
910 if (len == 0) {
911 *os << "{}";
912 } else {
913 *os << "{ ";
914 const size_t kThreshold = 18;
915 const size_t kChunkSize = 8;
916 // If the array has more than kThreshold elements, we'll have to
917 // omit some details by printing only the first and the last
918 // kChunkSize elements.
919 if (len <= kThreshold) {
920 PrintRawArrayTo(begin, len, os);
921 } else {
922 PrintRawArrayTo(begin, kChunkSize, os);
923 *os << ", ..., ";
924 PrintRawArrayTo(begin + len - kChunkSize, kChunkSize, os);
925 }
926 *os << " }";
927 }
928}
929// This overload prints a (const) char array compactly.
930GTEST_API_ void UniversalPrintArray(const char* begin, size_t len,
931 ::std::ostream* os);
932
933#ifdef __cpp_lib_char8_t
934// This overload prints a (const) char8_t array compactly.
935GTEST_API_ void UniversalPrintArray(const char8_t* begin, size_t len,
936 ::std::ostream* os);
937#endif
938
939// This overload prints a (const) char16_t array compactly.
940GTEST_API_ void UniversalPrintArray(const char16_t* begin, size_t len,
941 ::std::ostream* os);
942
943// This overload prints a (const) char32_t array compactly.
944GTEST_API_ void UniversalPrintArray(const char32_t* begin, size_t len,
945 ::std::ostream* os);
946
947// This overload prints a (const) wchar_t array compactly.
948GTEST_API_ void UniversalPrintArray(const wchar_t* begin, size_t len,
949 ::std::ostream* os);
950
951// Implements printing an array type T[N].
952template <typename T, size_t N>
953class UniversalPrinter<T[N]> {
954 public:
955 // Prints the given array, omitting some elements when there are too
956 // many.
957 static void Print(const T (&a)[N], ::std::ostream* os) {
958 UniversalPrintArray(a, N, os);
959 }
960};
961
962// Implements printing a reference type T&.
963template <typename T>
964class UniversalPrinter<T&> {
965 public:
966 // MSVC warns about adding const to a function type, so we want to
967 // disable the warning.
968 GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180)
969
970 static void Print(const T& value, ::std::ostream* os) {
971 // Prints the address of the value. We use reinterpret_cast here
972 // as static_cast doesn't compile when T is a function type.
973 *os << "@" << reinterpret_cast<const void*>(&value) << " ";
974
975 // Then prints the value itself.
976 UniversalPrint(value, os);
977 }
978
979 GTEST_DISABLE_MSC_WARNINGS_POP_()
980};
981
982// Prints a value tersely: for a reference type, the referenced value
983// (but not the address) is printed; for a (const) char pointer, the
984// NUL-terminated string (but not the pointer) is printed.
985
986template <typename T>
987class UniversalTersePrinter {
988 public:
989 static void Print(const T& value, ::std::ostream* os) {
990 UniversalPrint(value, os);
991 }
992};
993template <typename T>
994class UniversalTersePrinter<T&> {
995 public:
996 static void Print(const T& value, ::std::ostream* os) {
997 UniversalPrint(value, os);
998 }
999};
1000template <typename T>
1001class UniversalTersePrinter<std::reference_wrapper<T>> {
1002 public:
1003 static void Print(std::reference_wrapper<T> value, ::std::ostream* os) {
1004 UniversalTersePrinter<T>::Print(value.get(), os);
1005 }
1006};
1007template <typename T, size_t N>
1008class UniversalTersePrinter<T[N]> {
1009 public:
1010 static void Print(const T (&value)[N], ::std::ostream* os) {
1011 UniversalPrinter<T[N]>::Print(value, os);
1012 }
1013};
1014template <>
1015class UniversalTersePrinter<const char*> {
1016 public:
1017 static void Print(const char* str, ::std::ostream* os) {
1018 if (str == nullptr) {
1019 *os << "NULL";
1020 } else {
1021 UniversalPrint(value: std::string(str), os);
1022 }
1023 }
1024};
1025template <>
1026class UniversalTersePrinter<char*> : public UniversalTersePrinter<const char*> {
1027};
1028
1029#ifdef __cpp_lib_char8_t
1030template <>
1031class UniversalTersePrinter<const char8_t*> {
1032 public:
1033 static void Print(const char8_t* str, ::std::ostream* os) {
1034 if (str == nullptr) {
1035 *os << "NULL";
1036 } else {
1037 UniversalPrint(::std::u8string(str), os);
1038 }
1039 }
1040};
1041template <>
1042class UniversalTersePrinter<char8_t*>
1043 : public UniversalTersePrinter<const char8_t*> {};
1044#endif
1045
1046template <>
1047class UniversalTersePrinter<const char16_t*> {
1048 public:
1049 static void Print(const char16_t* str, ::std::ostream* os) {
1050 if (str == nullptr) {
1051 *os << "NULL";
1052 } else {
1053 UniversalPrint(value: ::std::u16string(str), os);
1054 }
1055 }
1056};
1057template <>
1058class UniversalTersePrinter<char16_t*>
1059 : public UniversalTersePrinter<const char16_t*> {};
1060
1061template <>
1062class UniversalTersePrinter<const char32_t*> {
1063 public:
1064 static void Print(const char32_t* str, ::std::ostream* os) {
1065 if (str == nullptr) {
1066 *os << "NULL";
1067 } else {
1068 UniversalPrint(value: ::std::u32string(str), os);
1069 }
1070 }
1071};
1072template <>
1073class UniversalTersePrinter<char32_t*>
1074 : public UniversalTersePrinter<const char32_t*> {};
1075
1076#if GTEST_HAS_STD_WSTRING
1077template <>
1078class UniversalTersePrinter<const wchar_t*> {
1079 public:
1080 static void Print(const wchar_t* str, ::std::ostream* os) {
1081 if (str == nullptr) {
1082 *os << "NULL";
1083 } else {
1084 UniversalPrint(value: ::std::wstring(str), os);
1085 }
1086 }
1087};
1088#endif
1089
1090template <>
1091class UniversalTersePrinter<wchar_t*> {
1092 public:
1093 static void Print(wchar_t* str, ::std::ostream* os) {
1094 UniversalTersePrinter<const wchar_t*>::Print(str, os);
1095 }
1096};
1097
1098template <typename T>
1099void UniversalTersePrint(const T& value, ::std::ostream* os) {
1100 UniversalTersePrinter<T>::Print(value, os);
1101}
1102
1103// Prints a value using the type inferred by the compiler. The
1104// difference between this and UniversalTersePrint() is that for a
1105// (const) char pointer, this prints both the pointer and the
1106// NUL-terminated string.
1107template <typename T>
1108void UniversalPrint(const T& value, ::std::ostream* os) {
1109 // A workarond for the bug in VC++ 7.1 that prevents us from instantiating
1110 // UniversalPrinter with T directly.
1111 typedef T T1;
1112 UniversalPrinter<T1>::Print(value, os);
1113}
1114
1115typedef ::std::vector<::std::string> Strings;
1116
1117// Tersely prints the first N fields of a tuple to a string vector,
1118// one element for each field.
1119template <typename Tuple>
1120void TersePrintPrefixToStrings(const Tuple&, std::integral_constant<size_t, 0>,
1121 Strings*) {}
1122template <typename Tuple, size_t I>
1123void TersePrintPrefixToStrings(const Tuple& t,
1124 std::integral_constant<size_t, I>,
1125 Strings* strings) {
1126 TersePrintPrefixToStrings(t, std::integral_constant<size_t, I - 1>(),
1127 strings);
1128 ::std::stringstream ss;
1129 UniversalTersePrint(std::get<I - 1>(t), &ss);
1130 strings->push_back(x: ss.str());
1131}
1132
1133// Prints the fields of a tuple tersely to a string vector, one
1134// element for each field. See the comment before
1135// UniversalTersePrint() for how we define "tersely".
1136template <typename Tuple>
1137Strings UniversalTersePrintTupleFieldsToStrings(const Tuple& value) {
1138 Strings result;
1139 TersePrintPrefixToStrings(
1140 value, std::integral_constant<size_t, std::tuple_size<Tuple>::value>(),
1141 &result);
1142 return result;
1143}
1144
1145} // namespace internal
1146
1147template <typename T>
1148::std::string PrintToString(const T& value) {
1149 ::std::stringstream ss;
1150 internal::UniversalTersePrinter<T>::Print(value, &ss);
1151 return ss.str();
1152}
1153
1154} // namespace testing
1155
1156// Include any custom printer added by the local installation.
1157// We must include this header at the end to make sure it can use the
1158// declarations from this file.
1159#include "gtest/internal/custom/gtest-printers.h"
1160
1161#endif // GOOGLETEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
1162