1// Copyright 2007, Google Inc. 2// All rights reserved. 3// 4// Redistribution and use in source and binary forms, with or without 5// modification, are permitted provided that the following conditions are 6// met: 7// 8// * Redistributions of source code must retain the above copyright 9// notice, this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above 11// copyright notice, this list of conditions and the following disclaimer 12// in the documentation and/or other materials provided with the 13// distribution. 14// * Neither the name of Google Inc. nor the names of its 15// contributors may be used to endorse or promote products derived from 16// this software without specific prior written permission. 17// 18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 30 31// Google Test - The Google C++ Testing and Mocking Framework 32// 33// This file implements a universal value printer that can print a 34// value of any type T: 35// 36// void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr); 37// 38// A user can teach this function how to print a class type T by 39// defining either operator<<() or PrintTo() in the namespace that 40// defines T. More specifically, the FIRST defined function in the 41// following list will be used (assuming T is defined in namespace 42// foo): 43// 44// 1. foo::PrintTo(const T&, ostream*) 45// 2. operator<<(ostream&, const T&) defined in either foo or the 46// global namespace. 47// 48// However if T is an STL-style container then it is printed element-wise 49// unless foo::PrintTo(const T&, ostream*) is defined. Note that 50// operator<<() is ignored for container types. 51// 52// If none of the above is defined, it will print the debug string of 53// the value if it is a protocol buffer, or print the raw bytes in the 54// value otherwise. 55// 56// To aid debugging: when T is a reference type, the address of the 57// value is also printed; when T is a (const) char pointer, both the 58// pointer value and the NUL-terminated string it points to are 59// printed. 60// 61// We also provide some convenient wrappers: 62// 63// // Prints a value to a string. For a (const or not) char 64// // pointer, the NUL-terminated string (but not the pointer) is 65// // printed. 66// std::string ::testing::PrintToString(const T& value); 67// 68// // Prints a value tersely: for a reference type, the referenced 69// // value (but not the address) is printed; for a (const or not) char 70// // pointer, the NUL-terminated string (but not the pointer) is 71// // printed. 72// void ::testing::internal::UniversalTersePrint(const T& value, ostream*); 73// 74// // Prints value using the type inferred by the compiler. The difference 75// // from UniversalTersePrint() is that this function prints both the 76// // pointer and the NUL-terminated string for a (const or not) char pointer. 77// void ::testing::internal::UniversalPrint(const T& value, ostream*); 78// 79// // Prints the fields of a tuple tersely to a string vector, one 80// // element for each field. Tuple support must be enabled in 81// // gtest-port.h. 82// std::vector<string> UniversalTersePrintTupleFieldsToStrings( 83// const Tuple& value); 84// 85// Known limitation: 86// 87// The print primitives print the elements of an STL-style container 88// using the compiler-inferred type of *iter where iter is a 89// const_iterator of the container. When const_iterator is an input 90// iterator but not a forward iterator, this inferred type may not 91// match value_type, and the print output may be incorrect. In 92// practice, this is rarely a problem as for most containers 93// const_iterator is a forward iterator. We'll fix this if there's an 94// actual need for it. Note that this fix cannot rely on value_type 95// being defined as many user-defined container types don't have 96// value_type. 97 98// GOOGLETEST_CM0001 DO NOT DELETE 99 100#ifndef GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_ 101#define GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_ 102 103#include <ostream> // NOLINT 104#include <sstream> 105#include <string> 106#include <utility> 107#include <vector> 108#include "gtest/internal/gtest-port.h" 109#include "gtest/internal/gtest-internal.h" 110 111#if GTEST_HAS_STD_TUPLE_ 112# include <tuple> 113#endif 114 115#if GTEST_HAS_ABSL 116#include "absl/strings/string_view.h" 117#include "absl/types/optional.h" 118#include "absl/types/variant.h" 119#endif // GTEST_HAS_ABSL 120 121namespace testing { 122 123// Definitions in the 'internal' and 'internal2' name spaces are 124// subject to change without notice. DO NOT USE THEM IN USER CODE! 125namespace internal2 { 126 127// Prints the given number of bytes in the given object to the given 128// ostream. 129GTEST_API_ void PrintBytesInObjectTo(const unsigned char* obj_bytes, 130 size_t count, 131 ::std::ostream* os); 132 133// For selecting which printer to use when a given type has neither << 134// nor PrintTo(). 135enum TypeKind { 136 kProtobuf, // a protobuf type 137 kConvertibleToInteger, // a type implicitly convertible to BiggestInt 138 // (e.g. a named or unnamed enum type) 139#if GTEST_HAS_ABSL 140 kConvertibleToStringView, // a type implicitly convertible to 141 // absl::string_view 142#endif 143 kOtherType // anything else 144}; 145 146// TypeWithoutFormatter<T, kTypeKind>::PrintValue(value, os) is called 147// by the universal printer to print a value of type T when neither 148// operator<< nor PrintTo() is defined for T, where kTypeKind is the 149// "kind" of T as defined by enum TypeKind. 150template <typename T, TypeKind kTypeKind> 151class TypeWithoutFormatter { 152 public: 153 // This default version is called when kTypeKind is kOtherType. 154 static void PrintValue(const T& value, ::std::ostream* os) { 155 PrintBytesInObjectTo(static_cast<const unsigned char*>( 156 reinterpret_cast<const void*>(&value)), 157 sizeof(value), os); 158 } 159}; 160 161// We print a protobuf using its ShortDebugString() when the string 162// doesn't exceed this many characters; otherwise we print it using 163// DebugString() for better readability. 164const size_t kProtobufOneLinerMaxLength = 50; 165 166template <typename T> 167class TypeWithoutFormatter<T, kProtobuf> { 168 public: 169 static void PrintValue(const T& value, ::std::ostream* os) { 170 std::string pretty_str = value.ShortDebugString(); 171 if (pretty_str.length() > kProtobufOneLinerMaxLength) { 172 pretty_str = "\n" + value.DebugString(); 173 } 174 *os << ("<" + pretty_str + ">"); 175 } 176}; 177 178template <typename T> 179class TypeWithoutFormatter<T, kConvertibleToInteger> { 180 public: 181 // Since T has no << operator or PrintTo() but can be implicitly 182 // converted to BiggestInt, we print it as a BiggestInt. 183 // 184 // Most likely T is an enum type (either named or unnamed), in which 185 // case printing it as an integer is the desired behavior. In case 186 // T is not an enum, printing it as an integer is the best we can do 187 // given that it has no user-defined printer. 188 static void PrintValue(const T& value, ::std::ostream* os) { 189 const internal::BiggestInt kBigInt = value; 190 *os << kBigInt; 191 } 192}; 193 194#if GTEST_HAS_ABSL 195template <typename T> 196class TypeWithoutFormatter<T, kConvertibleToStringView> { 197 public: 198 // Since T has neither operator<< nor PrintTo() but can be implicitly 199 // converted to absl::string_view, we print it as a absl::string_view. 200 // 201 // Note: the implementation is further below, as it depends on 202 // internal::PrintTo symbol which is defined later in the file. 203 static void PrintValue(const T& value, ::std::ostream* os); 204}; 205#endif 206 207// Prints the given value to the given ostream. If the value is a 208// protocol message, its debug string is printed; if it's an enum or 209// of a type implicitly convertible to BiggestInt, it's printed as an 210// integer; otherwise the bytes in the value are printed. This is 211// what UniversalPrinter<T>::Print() does when it knows nothing about 212// type T and T has neither << operator nor PrintTo(). 213// 214// A user can override this behavior for a class type Foo by defining 215// a << operator in the namespace where Foo is defined. 216// 217// We put this operator in namespace 'internal2' instead of 'internal' 218// to simplify the implementation, as much code in 'internal' needs to 219// use << in STL, which would conflict with our own << were it defined 220// in 'internal'. 221// 222// Note that this operator<< takes a generic std::basic_ostream<Char, 223// CharTraits> type instead of the more restricted std::ostream. If 224// we define it to take an std::ostream instead, we'll get an 225// "ambiguous overloads" compiler error when trying to print a type 226// Foo that supports streaming to std::basic_ostream<Char, 227// CharTraits>, as the compiler cannot tell whether 228// operator<<(std::ostream&, const T&) or 229// operator<<(std::basic_stream<Char, CharTraits>, const Foo&) is more 230// specific. 231template <typename Char, typename CharTraits, typename T> 232::std::basic_ostream<Char, CharTraits>& operator<<( 233 ::std::basic_ostream<Char, CharTraits>& os, const T& x) { 234 TypeWithoutFormatter<T, (internal::IsAProtocolMessage<T>::value 235 ? kProtobuf 236 : internal::ImplicitlyConvertible< 237 const T&, internal::BiggestInt>::value 238 ? kConvertibleToInteger 239 : 240#if GTEST_HAS_ABSL 241 internal::ImplicitlyConvertible< 242 const T&, absl::string_view>::value 243 ? kConvertibleToStringView 244 : 245#endif 246 kOtherType)>::PrintValue(x, &os); 247 return os; 248} 249 250} // namespace internal2 251} // namespace testing 252 253// This namespace MUST NOT BE NESTED IN ::testing, or the name look-up 254// magic needed for implementing UniversalPrinter won't work. 255namespace testing_internal { 256 257// Used to print a value that is not an STL-style container when the 258// user doesn't define PrintTo() for it. 259template <typename T> 260void DefaultPrintNonContainerTo(const T& value, ::std::ostream* os) { 261 // With the following statement, during unqualified name lookup, 262 // testing::internal2::operator<< appears as if it was declared in 263 // the nearest enclosing namespace that contains both 264 // ::testing_internal and ::testing::internal2, i.e. the global 265 // namespace. For more details, refer to the C++ Standard section 266 // 7.3.4-1 [namespace.udir]. This allows us to fall back onto 267 // testing::internal2::operator<< in case T doesn't come with a << 268 // operator. 269 // 270 // We cannot write 'using ::testing::internal2::operator<<;', which 271 // gcc 3.3 fails to compile due to a compiler bug. 272 using namespace ::testing::internal2; // NOLINT 273 274 // Assuming T is defined in namespace foo, in the next statement, 275 // the compiler will consider all of: 276 // 277 // 1. foo::operator<< (thanks to Koenig look-up), 278 // 2. ::operator<< (as the current namespace is enclosed in ::), 279 // 3. testing::internal2::operator<< (thanks to the using statement above). 280 // 281 // The operator<< whose type matches T best will be picked. 282 // 283 // We deliberately allow #2 to be a candidate, as sometimes it's 284 // impossible to define #1 (e.g. when foo is ::std, defining 285 // anything in it is undefined behavior unless you are a compiler 286 // vendor.). 287 *os << value; 288} 289 290} // namespace testing_internal 291 292namespace testing { 293namespace internal { 294 295// FormatForComparison<ToPrint, OtherOperand>::Format(value) formats a 296// value of type ToPrint that is an operand of a comparison assertion 297// (e.g. ASSERT_EQ). OtherOperand is the type of the other operand in 298// the comparison, and is used to help determine the best way to 299// format the value. In particular, when the value is a C string 300// (char pointer) and the other operand is an STL string object, we 301// want to format the C string as a string, since we know it is 302// compared by value with the string object. If the value is a char 303// pointer but the other operand is not an STL string object, we don't 304// know whether the pointer is supposed to point to a NUL-terminated 305// string, and thus want to print it as a pointer to be safe. 306// 307// INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM. 308 309// The default case. 310template <typename ToPrint, typename OtherOperand> 311class FormatForComparison { 312 public: 313 static ::std::string Format(const ToPrint& value) { 314 return ::testing::PrintToString(value); 315 } 316}; 317 318// Array. 319template <typename ToPrint, size_t N, typename OtherOperand> 320class FormatForComparison<ToPrint[N], OtherOperand> { 321 public: 322 static ::std::string Format(const ToPrint* value) { 323 return FormatForComparison<const ToPrint*, OtherOperand>::Format(value); 324 } 325}; 326 327// By default, print C string as pointers to be safe, as we don't know 328// whether they actually point to a NUL-terminated string. 329 330#define GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(CharType) \ 331 template <typename OtherOperand> \ 332 class FormatForComparison<CharType*, OtherOperand> { \ 333 public: \ 334 static ::std::string Format(CharType* value) { \ 335 return ::testing::PrintToString(static_cast<const void*>(value)); \ 336 } \ 337 } 338 339GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char); 340GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char); 341GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(wchar_t); 342GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const wchar_t); 343 344#undef GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_ 345 346// If a C string is compared with an STL string object, we know it's meant 347// to point to a NUL-terminated string, and thus can print it as a string. 348 349#define GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(CharType, OtherStringType) \ 350 template <> \ 351 class FormatForComparison<CharType*, OtherStringType> { \ 352 public: \ 353 static ::std::string Format(CharType* value) { \ 354 return ::testing::PrintToString(value); \ 355 } \ 356 } 357 358GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char, ::std::string); 359GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char, ::std::string); 360 361#if GTEST_HAS_GLOBAL_STRING 362GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char, ::string); 363GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char, ::string); 364#endif 365 366#if GTEST_HAS_GLOBAL_WSTRING 367GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(wchar_t, ::wstring); 368GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const wchar_t, ::wstring); 369#endif 370 371#if GTEST_HAS_STD_WSTRING 372GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(wchar_t, ::std::wstring); 373GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const wchar_t, ::std::wstring); 374#endif 375 376#undef GTEST_IMPL_FORMAT_C_STRING_AS_STRING_ 377 378// Formats a comparison assertion (e.g. ASSERT_EQ, EXPECT_LT, and etc) 379// operand to be used in a failure message. The type (but not value) 380// of the other operand may affect the format. This allows us to 381// print a char* as a raw pointer when it is compared against another 382// char* or void*, and print it as a C string when it is compared 383// against an std::string object, for example. 384// 385// INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM. 386template <typename T1, typename T2> 387std::string FormatForComparisonFailureMessage( 388 const T1& value, const T2& /* other_operand */) { 389 return FormatForComparison<T1, T2>::Format(value); 390} 391 392// UniversalPrinter<T>::Print(value, ostream_ptr) prints the given 393// value to the given ostream. The caller must ensure that 394// 'ostream_ptr' is not NULL, or the behavior is undefined. 395// 396// We define UniversalPrinter as a class template (as opposed to a 397// function template), as we need to partially specialize it for 398// reference types, which cannot be done with function templates. 399template <typename T> 400class UniversalPrinter; 401 402template <typename T> 403void UniversalPrint(const T& value, ::std::ostream* os); 404 405enum DefaultPrinterType { 406 kPrintContainer, 407 kPrintPointer, 408 kPrintFunctionPointer, 409 kPrintOther, 410}; 411template <DefaultPrinterType type> struct WrapPrinterType {}; 412 413// Used to print an STL-style container when the user doesn't define 414// a PrintTo() for it. 415template <typename C> 416void DefaultPrintTo(WrapPrinterType<kPrintContainer> /* dummy */, 417 const C& container, ::std::ostream* os) { 418 const size_t kMaxCount = 32; // The maximum number of elements to print. 419 *os << '{'; 420 size_t count = 0; 421 for (typename C::const_iterator it = container.begin(); 422 it != container.end(); ++it, ++count) { 423 if (count > 0) { 424 *os << ','; 425 if (count == kMaxCount) { // Enough has been printed. 426 *os << " ..."; 427 break; 428 } 429 } 430 *os << ' '; 431 // We cannot call PrintTo(*it, os) here as PrintTo() doesn't 432 // handle *it being a native array. 433 internal::UniversalPrint(*it, os); 434 } 435 436 if (count > 0) { 437 *os << ' '; 438 } 439 *os << '}'; 440} 441 442// Used to print a pointer that is neither a char pointer nor a member 443// pointer, when the user doesn't define PrintTo() for it. (A member 444// variable pointer or member function pointer doesn't really point to 445// a location in the address space. Their representation is 446// implementation-defined. Therefore they will be printed as raw 447// bytes.) 448template <typename T> 449void DefaultPrintTo(WrapPrinterType<kPrintPointer> /* dummy */, 450 T* p, ::std::ostream* os) { 451 if (p == NULL) { 452 *os << "NULL"; 453 } else { 454 // T is not a function type. We just call << to print p, 455 // relying on ADL to pick up user-defined << for their pointer 456 // types, if any. 457 *os << p; 458 } 459} 460template <typename T> 461void DefaultPrintTo(WrapPrinterType<kPrintFunctionPointer> /* dummy */, 462 T* p, ::std::ostream* os) { 463 if (p == NULL) { 464 *os << "NULL"; 465 } else { 466 // T is a function type, so '*os << p' doesn't do what we want 467 // (it just prints p as bool). We want to print p as a const 468 // void*. 469 *os << reinterpret_cast<const void*>(p); 470 } 471} 472 473// Used to print a non-container, non-pointer value when the user 474// doesn't define PrintTo() for it. 475template <typename T> 476void DefaultPrintTo(WrapPrinterType<kPrintOther> /* dummy */, 477 const T& value, ::std::ostream* os) { 478 ::testing_internal::DefaultPrintNonContainerTo(value, os); 479} 480 481// Prints the given value using the << operator if it has one; 482// otherwise prints the bytes in it. This is what 483// UniversalPrinter<T>::Print() does when PrintTo() is not specialized 484// or overloaded for type T. 485// 486// A user can override this behavior for a class type Foo by defining 487// an overload of PrintTo() in the namespace where Foo is defined. We 488// give the user this option as sometimes defining a << operator for 489// Foo is not desirable (e.g. the coding style may prevent doing it, 490// or there is already a << operator but it doesn't do what the user 491// wants). 492template <typename T> 493void PrintTo(const T& value, ::std::ostream* os) { 494 // DefaultPrintTo() is overloaded. The type of its first argument 495 // determines which version will be picked. 496 // 497 // Note that we check for container types here, prior to we check 498 // for protocol message types in our operator<<. The rationale is: 499 // 500 // For protocol messages, we want to give people a chance to 501 // override Google Mock's format by defining a PrintTo() or 502 // operator<<. For STL containers, other formats can be 503 // incompatible with Google Mock's format for the container 504 // elements; therefore we check for container types here to ensure 505 // that our format is used. 506 // 507 // Note that MSVC and clang-cl do allow an implicit conversion from 508 // pointer-to-function to pointer-to-object, but clang-cl warns on it. 509 // So don't use ImplicitlyConvertible if it can be helped since it will 510 // cause this warning, and use a separate overload of DefaultPrintTo for 511 // function pointers so that the `*os << p` in the object pointer overload 512 // doesn't cause that warning either. 513 DefaultPrintTo( 514 WrapPrinterType < 515 (sizeof(IsContainerTest<T>(0)) == sizeof(IsContainer)) && 516 !IsRecursiveContainer<T>::value 517 ? kPrintContainer 518 : !is_pointer<T>::value 519 ? kPrintOther 520#if GTEST_LANG_CXX11 521 : std::is_function<typename std::remove_pointer<T>::type>::value 522#else 523 : !internal::ImplicitlyConvertible<T, const void*>::value 524#endif 525 ? kPrintFunctionPointer 526 : kPrintPointer > (), 527 value, os); 528} 529 530// The following list of PrintTo() overloads tells 531// UniversalPrinter<T>::Print() how to print standard types (built-in 532// types, strings, plain arrays, and pointers). 533 534// Overloads for various char types. 535GTEST_API_ void PrintTo(unsigned char c, ::std::ostream* os); 536GTEST_API_ void PrintTo(signed char c, ::std::ostream* os); 537inline void PrintTo(char c, ::std::ostream* os) { 538 // When printing a plain char, we always treat it as unsigned. This 539 // way, the output won't be affected by whether the compiler thinks 540 // char is signed or not. 541 PrintTo(static_cast<unsigned char>(c), os); 542} 543 544// Overloads for other simple built-in types. 545inline void PrintTo(bool x, ::std::ostream* os) { 546 *os << (x ? "true" : "false"); 547} 548 549// Overload for wchar_t type. 550// Prints a wchar_t as a symbol if it is printable or as its internal 551// code otherwise and also as its decimal code (except for L'\0'). 552// The L'\0' char is printed as "L'\\0'". The decimal code is printed 553// as signed integer when wchar_t is implemented by the compiler 554// as a signed type and is printed as an unsigned integer when wchar_t 555// is implemented as an unsigned type. 556GTEST_API_ void PrintTo(wchar_t wc, ::std::ostream* os); 557 558// Overloads for C strings. 559GTEST_API_ void PrintTo(const char* s, ::std::ostream* os); 560inline void PrintTo(char* s, ::std::ostream* os) { 561 PrintTo(ImplicitCast_<const char*>(s), os); 562} 563 564// signed/unsigned char is often used for representing binary data, so 565// we print pointers to it as void* to be safe. 566inline void PrintTo(const signed char* s, ::std::ostream* os) { 567 PrintTo(ImplicitCast_<const void*>(s), os); 568} 569inline void PrintTo(signed char* s, ::std::ostream* os) { 570 PrintTo(ImplicitCast_<const void*>(s), os); 571} 572inline void PrintTo(const unsigned char* s, ::std::ostream* os) { 573 PrintTo(ImplicitCast_<const void*>(s), os); 574} 575inline void PrintTo(unsigned char* s, ::std::ostream* os) { 576 PrintTo(ImplicitCast_<const void*>(s), os); 577} 578 579// MSVC can be configured to define wchar_t as a typedef of unsigned 580// short. It defines _NATIVE_WCHAR_T_DEFINED when wchar_t is a native 581// type. When wchar_t is a typedef, defining an overload for const 582// wchar_t* would cause unsigned short* be printed as a wide string, 583// possibly causing invalid memory accesses. 584#if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED) 585// Overloads for wide C strings 586GTEST_API_ void PrintTo(const wchar_t* s, ::std::ostream* os); 587inline void PrintTo(wchar_t* s, ::std::ostream* os) { 588 PrintTo(ImplicitCast_<const wchar_t*>(s), os); 589} 590#endif 591 592// Overload for C arrays. Multi-dimensional arrays are printed 593// properly. 594 595// Prints the given number of elements in an array, without printing 596// the curly braces. 597template <typename T> 598void PrintRawArrayTo(const T a[], size_t count, ::std::ostream* os) { 599 UniversalPrint(a[0], os); 600 for (size_t i = 1; i != count; i++) { 601 *os << ", "; 602 UniversalPrint(a[i], os); 603 } 604} 605 606// Overloads for ::string and ::std::string. 607#if GTEST_HAS_GLOBAL_STRING 608GTEST_API_ void PrintStringTo(const ::string&s, ::std::ostream* os); 609inline void PrintTo(const ::string& s, ::std::ostream* os) { 610 PrintStringTo(s, os); 611} 612#endif // GTEST_HAS_GLOBAL_STRING 613 614GTEST_API_ void PrintStringTo(const ::std::string&s, ::std::ostream* os); 615inline void PrintTo(const ::std::string& s, ::std::ostream* os) { 616 PrintStringTo(s, os); 617} 618 619// Overloads for ::wstring and ::std::wstring. 620#if GTEST_HAS_GLOBAL_WSTRING 621GTEST_API_ void PrintWideStringTo(const ::wstring&s, ::std::ostream* os); 622inline void PrintTo(const ::wstring& s, ::std::ostream* os) { 623 PrintWideStringTo(s, os); 624} 625#endif // GTEST_HAS_GLOBAL_WSTRING 626 627#if GTEST_HAS_STD_WSTRING 628GTEST_API_ void PrintWideStringTo(const ::std::wstring&s, ::std::ostream* os); 629inline void PrintTo(const ::std::wstring& s, ::std::ostream* os) { 630 PrintWideStringTo(s, os); 631} 632#endif // GTEST_HAS_STD_WSTRING 633 634#if GTEST_HAS_ABSL 635// Overload for absl::string_view. 636inline void PrintTo(absl::string_view sp, ::std::ostream* os) { 637 PrintTo(::std::string(sp), os); 638} 639#endif // GTEST_HAS_ABSL 640 641#if GTEST_LANG_CXX11 642inline void PrintTo(std::nullptr_t, ::std::ostream* os) { *os << "(nullptr)"; } 643#endif // GTEST_LANG_CXX11 644 645#if GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_ 646// Helper function for printing a tuple. T must be instantiated with 647// a tuple type. 648template <typename T> 649void PrintTupleTo(const T& t, ::std::ostream* os); 650#endif // GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_ 651 652#if GTEST_HAS_TR1_TUPLE 653// Overload for ::std::tr1::tuple. Needed for printing function arguments, 654// which are packed as tuples. 655 656// Overloaded PrintTo() for tuples of various arities. We support 657// tuples of up-to 10 fields. The following implementation works 658// regardless of whether tr1::tuple is implemented using the 659// non-standard variadic template feature or not. 660 661inline void PrintTo(const ::std::tr1::tuple<>& t, ::std::ostream* os) { 662 PrintTupleTo(t, os); 663} 664 665template <typename T1> 666void PrintTo(const ::std::tr1::tuple<T1>& t, ::std::ostream* os) { 667 PrintTupleTo(t, os); 668} 669 670template <typename T1, typename T2> 671void PrintTo(const ::std::tr1::tuple<T1, T2>& t, ::std::ostream* os) { 672 PrintTupleTo(t, os); 673} 674 675template <typename T1, typename T2, typename T3> 676void PrintTo(const ::std::tr1::tuple<T1, T2, T3>& t, ::std::ostream* os) { 677 PrintTupleTo(t, os); 678} 679 680template <typename T1, typename T2, typename T3, typename T4> 681void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4>& t, ::std::ostream* os) { 682 PrintTupleTo(t, os); 683} 684 685template <typename T1, typename T2, typename T3, typename T4, typename T5> 686void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5>& t, 687 ::std::ostream* os) { 688 PrintTupleTo(t, os); 689} 690 691template <typename T1, typename T2, typename T3, typename T4, typename T5, 692 typename T6> 693void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6>& t, 694 ::std::ostream* os) { 695 PrintTupleTo(t, os); 696} 697 698template <typename T1, typename T2, typename T3, typename T4, typename T5, 699 typename T6, typename T7> 700void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7>& t, 701 ::std::ostream* os) { 702 PrintTupleTo(t, os); 703} 704 705template <typename T1, typename T2, typename T3, typename T4, typename T5, 706 typename T6, typename T7, typename T8> 707void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8>& t, 708 ::std::ostream* os) { 709 PrintTupleTo(t, os); 710} 711 712template <typename T1, typename T2, typename T3, typename T4, typename T5, 713 typename T6, typename T7, typename T8, typename T9> 714void PrintTo(const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8, T9>& t, 715 ::std::ostream* os) { 716 PrintTupleTo(t, os); 717} 718 719template <typename T1, typename T2, typename T3, typename T4, typename T5, 720 typename T6, typename T7, typename T8, typename T9, typename T10> 721void PrintTo( 722 const ::std::tr1::tuple<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>& t, 723 ::std::ostream* os) { 724 PrintTupleTo(t, os); 725} 726#endif // GTEST_HAS_TR1_TUPLE 727 728#if GTEST_HAS_STD_TUPLE_ 729template <typename... Types> 730void PrintTo(const ::std::tuple<Types...>& t, ::std::ostream* os) { 731 PrintTupleTo(t, os); 732} 733#endif // GTEST_HAS_STD_TUPLE_ 734 735// Overload for std::pair. 736template <typename T1, typename T2> 737void PrintTo(const ::std::pair<T1, T2>& value, ::std::ostream* os) { 738 *os << '('; 739 // We cannot use UniversalPrint(value.first, os) here, as T1 may be 740 // a reference type. The same for printing value.second. 741 UniversalPrinter<T1>::Print(value.first, os); 742 *os << ", "; 743 UniversalPrinter<T2>::Print(value.second, os); 744 *os << ')'; 745} 746 747// Implements printing a non-reference type T by letting the compiler 748// pick the right overload of PrintTo() for T. 749template <typename T> 750class UniversalPrinter { 751 public: 752 // MSVC warns about adding const to a function type, so we want to 753 // disable the warning. 754 GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180) 755 756 // Note: we deliberately don't call this PrintTo(), as that name 757 // conflicts with ::testing::internal::PrintTo in the body of the 758 // function. 759 static void Print(const T& value, ::std::ostream* os) { 760 // By default, ::testing::internal::PrintTo() is used for printing 761 // the value. 762 // 763 // Thanks to Koenig look-up, if T is a class and has its own 764 // PrintTo() function defined in its namespace, that function will 765 // be visible here. Since it is more specific than the generic ones 766 // in ::testing::internal, it will be picked by the compiler in the 767 // following statement - exactly what we want. 768 PrintTo(value, os); 769 } 770 771 GTEST_DISABLE_MSC_WARNINGS_POP_() 772}; 773 774#if GTEST_HAS_ABSL 775 776// Printer for absl::optional 777 778template <typename T> 779class UniversalPrinter<::absl::optional<T>> { 780 public: 781 static void Print(const ::absl::optional<T>& value, ::std::ostream* os) { 782 *os << '('; 783 if (!value) { 784 *os << "nullopt"; 785 } else { 786 UniversalPrint(*value, os); 787 } 788 *os << ')'; 789 } 790}; 791 792// Printer for absl::variant 793 794template <typename... T> 795class UniversalPrinter<::absl::variant<T...>> { 796 public: 797 static void Print(const ::absl::variant<T...>& value, ::std::ostream* os) { 798 *os << '('; 799 absl::visit(Visitor{os}, value); 800 *os << ')'; 801 } 802 803 private: 804 struct Visitor { 805 template <typename U> 806 void operator()(const U& u) const { 807 *os << "'" << GetTypeName<U>() << "' with value "; 808 UniversalPrint(u, os); 809 } 810 ::std::ostream* os; 811 }; 812}; 813 814#endif // GTEST_HAS_ABSL 815 816// UniversalPrintArray(begin, len, os) prints an array of 'len' 817// elements, starting at address 'begin'. 818template <typename T> 819void UniversalPrintArray(const T* begin, size_t len, ::std::ostream* os) { 820 if (len == 0) { 821 *os << "{}"; 822 } else { 823 *os << "{ "; 824 const size_t kThreshold = 18; 825 const size_t kChunkSize = 8; 826 // If the array has more than kThreshold elements, we'll have to 827 // omit some details by printing only the first and the last 828 // kChunkSize elements. 829 // FIXME: let the user control the threshold using a flag. 830 if (len <= kThreshold) { 831 PrintRawArrayTo(begin, len, os); 832 } else { 833 PrintRawArrayTo(begin, kChunkSize, os); 834 *os << ", ..., "; 835 PrintRawArrayTo(begin + len - kChunkSize, kChunkSize, os); 836 } 837 *os << " }"; 838 } 839} 840// This overload prints a (const) char array compactly. 841GTEST_API_ void UniversalPrintArray( 842 const char* begin, size_t len, ::std::ostream* os); 843 844// This overload prints a (const) wchar_t array compactly. 845GTEST_API_ void UniversalPrintArray( 846 const wchar_t* begin, size_t len, ::std::ostream* os); 847 848// Implements printing an array type T[N]. 849template <typename T, size_t N> 850class UniversalPrinter<T[N]> { 851 public: 852 // Prints the given array, omitting some elements when there are too 853 // many. 854 static void Print(const T (&a)[N], ::std::ostream* os) { 855 UniversalPrintArray(a, N, os); 856 } 857}; 858 859// Implements printing a reference type T&. 860template <typename T> 861class UniversalPrinter<T&> { 862 public: 863 // MSVC warns about adding const to a function type, so we want to 864 // disable the warning. 865 GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180) 866 867 static void Print(const T& value, ::std::ostream* os) { 868 // Prints the address of the value. We use reinterpret_cast here 869 // as static_cast doesn't compile when T is a function type. 870 *os << "@" << reinterpret_cast<const void*>(&value) << " "; 871 872 // Then prints the value itself. 873 UniversalPrint(value, os); 874 } 875 876 GTEST_DISABLE_MSC_WARNINGS_POP_() 877}; 878 879// Prints a value tersely: for a reference type, the referenced value 880// (but not the address) is printed; for a (const) char pointer, the 881// NUL-terminated string (but not the pointer) is printed. 882 883template <typename T> 884class UniversalTersePrinter { 885 public: 886 static void Print(const T& value, ::std::ostream* os) { 887 UniversalPrint(value, os); 888 } 889}; 890template <typename T> 891class UniversalTersePrinter<T&> { 892 public: 893 static void Print(const T& value, ::std::ostream* os) { 894 UniversalPrint(value, os); 895 } 896}; 897template <typename T, size_t N> 898class UniversalTersePrinter<T[N]> { 899 public: 900 static void Print(const T (&value)[N], ::std::ostream* os) { 901 UniversalPrinter<T[N]>::Print(value, os); 902 } 903}; 904template <> 905class UniversalTersePrinter<const char*> { 906 public: 907 static void Print(const char* str, ::std::ostream* os) { 908 if (str == NULL) { 909 *os << "NULL"; 910 } else { 911 UniversalPrint(std::string(str), os); 912 } 913 } 914}; 915template <> 916class UniversalTersePrinter<char*> { 917 public: 918 static void Print(char* str, ::std::ostream* os) { 919 UniversalTersePrinter<const char*>::Print(str, os); 920 } 921}; 922 923#if GTEST_HAS_STD_WSTRING 924template <> 925class UniversalTersePrinter<const wchar_t*> { 926 public: 927 static void Print(const wchar_t* str, ::std::ostream* os) { 928 if (str == NULL) { 929 *os << "NULL"; 930 } else { 931 UniversalPrint(::std::wstring(str), os); 932 } 933 } 934}; 935#endif 936 937template <> 938class UniversalTersePrinter<wchar_t*> { 939 public: 940 static void Print(wchar_t* str, ::std::ostream* os) { 941 UniversalTersePrinter<const wchar_t*>::Print(str, os); 942 } 943}; 944 945template <typename T> 946void UniversalTersePrint(const T& value, ::std::ostream* os) { 947 UniversalTersePrinter<T>::Print(value, os); 948} 949 950// Prints a value using the type inferred by the compiler. The 951// difference between this and UniversalTersePrint() is that for a 952// (const) char pointer, this prints both the pointer and the 953// NUL-terminated string. 954template <typename T> 955void UniversalPrint(const T& value, ::std::ostream* os) { 956 // A workarond for the bug in VC++ 7.1 that prevents us from instantiating 957 // UniversalPrinter with T directly. 958 typedef T T1; 959 UniversalPrinter<T1>::Print(value, os); 960} 961 962typedef ::std::vector< ::std::string> Strings; 963 964// TuplePolicy<TupleT> must provide: 965// - tuple_size 966// size of tuple TupleT. 967// - get<size_t I>(const TupleT& t) 968// static function extracting element I of tuple TupleT. 969// - tuple_element<size_t I>::type 970// type of element I of tuple TupleT. 971template <typename TupleT> 972struct TuplePolicy; 973 974#if GTEST_HAS_TR1_TUPLE 975template <typename TupleT> 976struct TuplePolicy { 977 typedef TupleT Tuple; 978 static const size_t tuple_size = ::std::tr1::tuple_size<Tuple>::value; 979 980 template <size_t I> 981 struct tuple_element : ::std::tr1::tuple_element<static_cast<int>(I), Tuple> { 982 }; 983 984 template <size_t I> 985 static typename AddReference<const typename ::std::tr1::tuple_element< 986 static_cast<int>(I), Tuple>::type>::type 987 get(const Tuple& tuple) { 988 return ::std::tr1::get<I>(tuple); 989 } 990}; 991template <typename TupleT> 992const size_t TuplePolicy<TupleT>::tuple_size; 993#endif // GTEST_HAS_TR1_TUPLE 994 995#if GTEST_HAS_STD_TUPLE_ 996template <typename... Types> 997struct TuplePolicy< ::std::tuple<Types...> > { 998 typedef ::std::tuple<Types...> Tuple; 999 static const size_t tuple_size = ::std::tuple_size<Tuple>::value; 1000 1001 template <size_t I> 1002 struct tuple_element : ::std::tuple_element<I, Tuple> {}; 1003 1004 template <size_t I> 1005 static const typename ::std::tuple_element<I, Tuple>::type& get( 1006 const Tuple& tuple) { 1007 return ::std::get<I>(tuple); 1008 } 1009}; 1010template <typename... Types> 1011const size_t TuplePolicy< ::std::tuple<Types...> >::tuple_size; 1012#endif // GTEST_HAS_STD_TUPLE_ 1013 1014#if GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_ 1015// This helper template allows PrintTo() for tuples and 1016// UniversalTersePrintTupleFieldsToStrings() to be defined by 1017// induction on the number of tuple fields. The idea is that 1018// TuplePrefixPrinter<N>::PrintPrefixTo(t, os) prints the first N 1019// fields in tuple t, and can be defined in terms of 1020// TuplePrefixPrinter<N - 1>. 1021// 1022// The inductive case. 1023template <size_t N> 1024struct TuplePrefixPrinter { 1025 // Prints the first N fields of a tuple. 1026 template <typename Tuple> 1027 static void PrintPrefixTo(const Tuple& t, ::std::ostream* os) { 1028 TuplePrefixPrinter<N - 1>::PrintPrefixTo(t, os); 1029 GTEST_INTENTIONAL_CONST_COND_PUSH_() 1030 if (N > 1) { 1031 GTEST_INTENTIONAL_CONST_COND_POP_() 1032 *os << ", "; 1033 } 1034 UniversalPrinter< 1035 typename TuplePolicy<Tuple>::template tuple_element<N - 1>::type> 1036 ::Print(TuplePolicy<Tuple>::template get<N - 1>(t), os); 1037 } 1038 1039 // Tersely prints the first N fields of a tuple to a string vector, 1040 // one element for each field. 1041 template <typename Tuple> 1042 static void TersePrintPrefixToStrings(const Tuple& t, Strings* strings) { 1043 TuplePrefixPrinter<N - 1>::TersePrintPrefixToStrings(t, strings); 1044 ::std::stringstream ss; 1045 UniversalTersePrint(TuplePolicy<Tuple>::template get<N - 1>(t), &ss); 1046 strings->push_back(ss.str()); 1047 } 1048}; 1049 1050// Base case. 1051template <> 1052struct TuplePrefixPrinter<0> { 1053 template <typename Tuple> 1054 static void PrintPrefixTo(const Tuple&, ::std::ostream*) {} 1055 1056 template <typename Tuple> 1057 static void TersePrintPrefixToStrings(const Tuple&, Strings*) {} 1058}; 1059 1060// Helper function for printing a tuple. 1061// Tuple must be either std::tr1::tuple or std::tuple type. 1062template <typename Tuple> 1063void PrintTupleTo(const Tuple& t, ::std::ostream* os) { 1064 *os << "("; 1065 TuplePrefixPrinter<TuplePolicy<Tuple>::tuple_size>::PrintPrefixTo(t, os); 1066 *os << ")"; 1067} 1068 1069// Prints the fields of a tuple tersely to a string vector, one 1070// element for each field. See the comment before 1071// UniversalTersePrint() for how we define "tersely". 1072template <typename Tuple> 1073Strings UniversalTersePrintTupleFieldsToStrings(const Tuple& value) { 1074 Strings result; 1075 TuplePrefixPrinter<TuplePolicy<Tuple>::tuple_size>:: 1076 TersePrintPrefixToStrings(value, &result); 1077 return result; 1078} 1079#endif // GTEST_HAS_TR1_TUPLE || GTEST_HAS_STD_TUPLE_ 1080 1081} // namespace internal 1082 1083#if GTEST_HAS_ABSL 1084namespace internal2 { 1085template <typename T> 1086void TypeWithoutFormatter<T, kConvertibleToStringView>::PrintValue( 1087 const T& value, ::std::ostream* os) { 1088 internal::PrintTo(absl::string_view(value), os); 1089} 1090} // namespace internal2 1091#endif 1092 1093template <typename T> 1094::std::string PrintToString(const T& value) { 1095 ::std::stringstream ss; 1096 internal::UniversalTersePrinter<T>::Print(value, &ss); 1097 return ss.str(); 1098} 1099 1100} // namespace testing 1101 1102// Include any custom printer added by the local installation. 1103// We must include this header at the end to make sure it can use the 1104// declarations from this file. 1105#include "gtest/internal/custom/gtest-printers.h" 1106 1107#endif // GTEST_INCLUDE_GTEST_GTEST_PRINTERS_H_ 1108