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// Copyright 2007, Google Inc.
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// All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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//     * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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//     * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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//     * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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// Google Test - The Google C++ Testing and Mocking Framework
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//
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// This file implements a universal value printer that can print a
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// value of any type T:
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//
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//   void ::testing::internal::UniversalPrinter<T>::Print(value, ostream_ptr);
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//
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// A user can teach this function how to print a class type T by
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// defining either operator<<() or PrintTo() in the namespace that
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// defines T.  More specifically, the FIRST defined function in the
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// following list will be used (assuming T is defined in namespace
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// foo):
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//
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//   1. foo::PrintTo(const T&, ostream*)
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//   2. operator<<(ostream&, const T&) defined in either foo or the
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//      global namespace.
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// * Prefer AbslStringify(..) to operator<<(..), per https://abseil.io/tips/215.
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// * Define foo::PrintTo(..) if the type already has AbslStringify(..), but an
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//   alternative presentation in test results is of interest.
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//
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// However if T is an STL-style container then it is printed element-wise
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// unless foo::PrintTo(const T&, ostream*) is defined. Note that
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// operator<<() is ignored for container types.
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//
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// If none of the above is defined, it will print the debug string of
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// the value if it is a protocol buffer, or print the raw bytes in the
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// value otherwise.
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//
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// To aid debugging: when T is a reference type, the address of the
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// value is also printed; when T is a (const) char pointer, both the
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// pointer value and the NUL-terminated string it points to are
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// printed.
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//
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// We also provide some convenient wrappers:
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//
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//   // Prints a value to a string.  For a (const or not) char
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//   // pointer, the NUL-terminated string (but not the pointer) is
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//   // printed.
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//   std::string ::testing::PrintToString(const T& value);
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//
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//   // Prints a value tersely: for a reference type, the referenced
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//   // value (but not the address) is printed; for a (const or not) char
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//   // pointer, the NUL-terminated string (but not the pointer) is
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//   // printed.
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//   void ::testing::internal::UniversalTersePrint(const T& value, ostream*);
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//
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//   // Prints value using the type inferred by the compiler.  The difference
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//   // from UniversalTersePrint() is that this function prints both the
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//   // pointer and the NUL-terminated string for a (const or not) char pointer.
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//   void ::testing::internal::UniversalPrint(const T& value, ostream*);
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//
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//   // Prints the fields of a tuple tersely to a string vector, one
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//   // element for each field. Tuple support must be enabled in
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//   // gtest-port.h.
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//   std::vector<string> UniversalTersePrintTupleFieldsToStrings(
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//       const Tuple& value);
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//
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// Known limitation:
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//
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// The print primitives print the elements of an STL-style container
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// using the compiler-inferred type of *iter where iter is a
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// const_iterator of the container.  When const_iterator is an input
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// iterator but not a forward iterator, this inferred type may not
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// match value_type, and the print output may be incorrect.  In
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// practice, this is rarely a problem as for most containers
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// const_iterator is a forward iterator.  We'll fix this if there's an
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// actual need for it.  Note that this fix cannot rely on value_type
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// being defined as many user-defined container types don't have
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// value_type.
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// IWYU pragma: private, include "gtest/gtest.h"
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// IWYU pragma: friend gtest/.*
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// IWYU pragma: friend gmock/.*
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#ifndef GOOGLETEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
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#define GOOGLETEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
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#include <functional>
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#include <memory>
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#include <ostream>  // NOLINT
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#include <sstream>
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#include <string>
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#include <tuple>
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#include <type_traits>
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#include <typeinfo>
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#include <utility>
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#include <vector>
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#ifdef GTEST_HAS_ABSL
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#include "absl/strings/has_absl_stringify.h"
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#include "absl/strings/str_cat.h"
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#endif  // GTEST_HAS_ABSL
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#include "gtest/internal/gtest-internal.h"
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#include "gtest/internal/gtest-port.h"
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#if GTEST_INTERNAL_HAS_STD_SPAN
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#include <span>  // NOLINT
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#endif           // GTEST_INTERNAL_HAS_STD_SPAN
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#if GTEST_INTERNAL_HAS_COMPARE_LIB
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#include <compare>  // NOLINT
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#endif              // GTEST_INTERNAL_HAS_COMPARE_LIB
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namespace testing {
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// Definitions in the internal* namespaces are subject to change without notice.
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// DO NOT USE THEM IN USER CODE!
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namespace internal {
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template <typename T>
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void UniversalPrint(const T& value, ::std::ostream* os);
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template <typename T>
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struct IsStdSpan {
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  static constexpr bool value = false;
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};
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#if GTEST_INTERNAL_HAS_STD_SPAN
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template <typename E>
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struct IsStdSpan<std::span<E>> {
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  static constexpr bool value = true;
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};
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#endif  // GTEST_INTERNAL_HAS_STD_SPAN
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// Used to print an STL-style container when the user doesn't define
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// a PrintTo() for it.
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//
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// NOTE: Since std::span does not have const_iterator until C++23, it would
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// fail IsContainerTest before C++23. However, IsContainerTest only uses
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// the presence of const_iterator to avoid treating iterators as containers
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// because of iterator::iterator. Which means std::span satisfies the *intended*
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// condition of IsContainerTest.
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struct ContainerPrinter {
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  template <typename T,
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            typename = typename std::enable_if<
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                ((sizeof(IsContainerTest<T>(0)) == sizeof(IsContainer)) &&
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                 !IsRecursiveContainer<T>::value) ||
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                IsStdSpan<T>::value>::type>
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  static void PrintValue(const T& container, std::ostream* os) {
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    const size_t kMaxCount = 32;  // The maximum number of elements to print.
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    *os << '{';
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    size_t count = 0;
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    for (auto&& elem : container) {
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      if (count > 0) {
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        *os << ',';
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        if (count == kMaxCount) {  // Enough has been printed.
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          *os << " ...";
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          break;
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        }
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      }
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      *os << ' ';
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      // We cannot call PrintTo(elem, os) here as PrintTo() doesn't
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      // handle `elem` being a native array.
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      internal::UniversalPrint(elem, os);
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      ++count;
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    }
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    if (count > 0) {
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      *os << ' ';
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    }
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    *os << '}';
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  }
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};
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// Used to print a pointer that is neither a char pointer nor a member
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// pointer, when the user doesn't define PrintTo() for it.  (A member
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// variable pointer or member function pointer doesn't really point to
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// a location in the address space.  Their representation is
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// implementation-defined.  Therefore they will be printed as raw
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// bytes.)
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struct FunctionPointerPrinter {
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  template <typename T, typename = typename std::enable_if<
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                            std::is_function<T>::value>::type>
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  static void PrintValue(T* p, ::std::ostream* os) {
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    if (p == nullptr) {
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      *os << "NULL";
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    } else {
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      // T is a function type, so '*os << p' doesn't do what we want
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      // (it just prints p as bool).  We want to print p as a const
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      // void*.
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      *os << reinterpret_cast<const void*>(p);
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    }
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  }
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};
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struct PointerPrinter {
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  template <typename T>
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  static void PrintValue(T* p, ::std::ostream* os) {
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    if (p == nullptr) {
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      *os << "NULL";
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    } else {
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      // T is not a function type.  We just call << to print p,
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      // relying on ADL to pick up user-defined << for their pointer
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      // types, if any.
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      *os << p;
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    }
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  }
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};
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namespace internal_stream_operator_without_lexical_name_lookup {
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// The presence of an operator<< here will terminate lexical scope lookup
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// straight away (even though it cannot be a match because of its argument
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// types). Thus, the two operator<< calls in StreamPrinter will find only ADL
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// candidates.
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struct LookupBlocker {};
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void operator<<(LookupBlocker, LookupBlocker);
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struct StreamPrinter {
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  template <typename T,
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            // Don't accept member pointers here. We'd print them via implicit
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            // conversion to bool, which isn't useful.
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            typename = typename std::enable_if<
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                !std::is_member_pointer<T>::value>::type>
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  // Only accept types for which we can find a streaming operator via
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  // ADL (possibly involving implicit conversions).
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  // (Use SFINAE via return type, because it seems GCC < 12 doesn't handle name
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  // lookup properly when we do it in the template parameter list.)
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  static auto PrintValue(const T& value,
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                         ::std::ostream* os) -> decltype((void)(*os << value)) {
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    // Call streaming operator found by ADL, possibly with implicit conversions
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    // of the arguments.
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    *os << value;
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  }
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};
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}  // namespace internal_stream_operator_without_lexical_name_lookup
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struct ProtobufPrinter {
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  // We print a protobuf using its ShortDebugString() when the string
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  // doesn't exceed this many characters; otherwise we print it using
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  // DebugString() for better readability.
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  static const size_t kProtobufOneLinerMaxLength = 50;
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  template <typename T,
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            typename = typename std::enable_if<
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                internal::HasDebugStringAndShortDebugString<T>::value>::type>
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  static void PrintValue(const T& value, ::std::ostream* os) {
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    std::string pretty_str = value.ShortDebugString();
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    if (pretty_str.length() > kProtobufOneLinerMaxLength) {
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      pretty_str = "\n" + value.DebugString();
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    }
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    *os << ("<" + pretty_str + ">");
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  }
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};
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struct ConvertibleToIntegerPrinter {
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  // Since T has no << operator or PrintTo() but can be implicitly
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  // converted to BiggestInt, we print it as a BiggestInt.
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  //
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  // Most likely T is an enum type (either named or unnamed), in which
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  // case printing it as an integer is the desired behavior.  In case
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  // T is not an enum, printing it as an integer is the best we can do
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  // given that it has no user-defined printer.
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  static void PrintValue(internal::BiggestInt value, ::std::ostream* os) {
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    *os << value;
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  }
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};
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struct ConvertibleToStringViewPrinter {
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#if GTEST_INTERNAL_HAS_STRING_VIEW
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  static void PrintValue(internal::StringView value, ::std::ostream* os) {
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    internal::UniversalPrint(value, os);
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  }
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#endif
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};
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#ifdef GTEST_HAS_ABSL
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struct ConvertibleToAbslStringifyPrinter {
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  template <typename T,
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            typename = typename std::enable_if<
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                absl::HasAbslStringify<T>::value>::type>  // NOLINT
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  static void PrintValue(const T& value, ::std::ostream* os) {
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    *os << absl::StrCat(value);
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  }
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};
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#endif  // GTEST_HAS_ABSL
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// Prints the given number of bytes in the given object to the given
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// ostream.
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GTEST_API_ void PrintBytesInObjectTo(const unsigned char* obj_bytes,
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                                     size_t count, ::std::ostream* os);
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struct RawBytesPrinter {
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  // SFINAE on `sizeof` to make sure we have a complete type.
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  template <typename T, size_t = sizeof(T)>
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  static void PrintValue(const T& value, ::std::ostream* os) {
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    PrintBytesInObjectTo(
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        static_cast<const unsigned char*>(
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            // Load bearing cast to void* to support iOS
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            reinterpret_cast<const void*>(std::addressof(value))),
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        sizeof(value), os);
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  }
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};
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struct FallbackPrinter {
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  template <typename T>
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  static void PrintValue(const T&, ::std::ostream* os) {
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    *os << "(incomplete type)";
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  }
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};
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// Try every printer in order and return the first one that works.
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template <typename T, typename E, typename Printer, typename... Printers>
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struct FindFirstPrinter : FindFirstPrinter<T, E, Printers...> {};
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template <typename T, typename Printer, typename... Printers>
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struct FindFirstPrinter<
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    T, decltype(Printer::PrintValue(std::declval<const T&>(), nullptr)),
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    Printer, Printers...> {
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  using type = Printer;
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};
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// Select the best printer in the following order:
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//  - Print containers (they have begin/end/etc).
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//  - Print function pointers.
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//  - Print object pointers.
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//  - Print protocol buffers.
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//  - Use the stream operator, if available.
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//  - Print types convertible to BiggestInt.
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//  - Print types convertible to StringView, if available.
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//  - Fallback to printing the raw bytes of the object.
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template <typename T>
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void PrintWithFallback(const T& value, ::std::ostream* os) {
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  using Printer = typename FindFirstPrinter<
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      T, void, ContainerPrinter, FunctionPointerPrinter, PointerPrinter,
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      ProtobufPrinter,
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#ifdef GTEST_HAS_ABSL
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      ConvertibleToAbslStringifyPrinter,
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#endif  // GTEST_HAS_ABSL
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      internal_stream_operator_without_lexical_name_lookup::StreamPrinter,
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      ConvertibleToIntegerPrinter, ConvertibleToStringViewPrinter,
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      RawBytesPrinter, FallbackPrinter>::type;
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  Printer::PrintValue(value, os);
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}
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// FormatForComparison<ToPrint, OtherOperand>::Format(value) formats a
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// value of type ToPrint that is an operand of a comparison assertion
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// (e.g. ASSERT_EQ).  OtherOperand is the type of the other operand in
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// the comparison, and is used to help determine the best way to
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// format the value.  In particular, when the value is a C string
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// (char pointer) and the other operand is an STL string object, we
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// want to format the C string as a string, since we know it is
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// compared by value with the string object.  If the value is a char
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// pointer but the other operand is not an STL string object, we don't
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// know whether the pointer is supposed to point to a NUL-terminated
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// string, and thus want to print it as a pointer to be safe.
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//
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// INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM.
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// The default case.
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template <typename ToPrint, typename OtherOperand>
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class FormatForComparison {
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 public:
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  static ::std::string Format(const ToPrint& value) {
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    return ::testing::PrintToString(value);
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  }
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};
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// Array.
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template <typename ToPrint, size_t N, typename OtherOperand>
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class FormatForComparison<ToPrint[N], OtherOperand> {
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 public:
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  static ::std::string Format(const ToPrint* value) {
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    return FormatForComparison<const ToPrint*, OtherOperand>::Format(value);
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  }
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};
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// By default, print C string as pointers to be safe, as we don't know
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// whether they actually point to a NUL-terminated string.
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#define GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(CharType)                \
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  template <typename OtherOperand>                                      \
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  class FormatForComparison<CharType*, OtherOperand> {                  \
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   public:                                                              \
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    static ::std::string Format(CharType* value) {                      \
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      return ::testing::PrintToString(static_cast<const void*>(value)); \
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    }                                                                   \
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  }
408

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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(wchar_t);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const wchar_t);
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#ifdef __cpp_lib_char8_t
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char8_t);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char8_t);
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#endif
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char16_t);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char16_t);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(char32_t);
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GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_(const char32_t);
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#undef GTEST_IMPL_FORMAT_C_STRING_AS_POINTER_
423

424
// If a C string is compared with an STL string object, we know it's meant
425
// to point to a NUL-terminated string, and thus can print it as a string.
426

427
#define GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(CharType, OtherStringType) \
428
  template <>                                                            \
429
  class FormatForComparison<CharType*, OtherStringType> {                \
430
   public:                                                               \
431
    static ::std::string Format(CharType* value) {                       \
432
      return ::testing::PrintToString(value);                            \
433
    }                                                                    \
434
  }
435

436
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char, ::std::string);
437
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char, ::std::string);
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#ifdef __cpp_lib_char8_t
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GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char8_t, ::std::u8string);
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GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char8_t, ::std::u8string);
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#endif
442
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char16_t, ::std::u16string);
443
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char16_t, ::std::u16string);
444
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(char32_t, ::std::u32string);
445
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const char32_t, ::std::u32string);
446

447
#if GTEST_HAS_STD_WSTRING
448
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(wchar_t, ::std::wstring);
449
GTEST_IMPL_FORMAT_C_STRING_AS_STRING_(const wchar_t, ::std::wstring);
450
#endif
451

452
#undef GTEST_IMPL_FORMAT_C_STRING_AS_STRING_
453

454
// Formats a comparison assertion (e.g. ASSERT_EQ, EXPECT_LT, and etc)
455
// operand to be used in a failure message.  The type (but not value)
456
// of the other operand may affect the format.  This allows us to
457
// print a char* as a raw pointer when it is compared against another
458
// char* or void*, and print it as a C string when it is compared
459
// against an std::string object, for example.
460
//
461
// INTERNAL IMPLEMENTATION - DO NOT USE IN A USER PROGRAM.
462
template <typename T1, typename T2>
463
std::string FormatForComparisonFailureMessage(const T1& value,
464
                                              const T2& /* other_operand */) {
465
  return FormatForComparison<T1, T2>::Format(value);
466
}
467

468
// UniversalPrinter<T>::Print(value, ostream_ptr) prints the given
469
// value to the given ostream.  The caller must ensure that
470
// 'ostream_ptr' is not NULL, or the behavior is undefined.
471
//
472
// We define UniversalPrinter as a class template (as opposed to a
473
// function template), as we need to partially specialize it for
474
// reference types, which cannot be done with function templates.
475
template <typename T>
476
class UniversalPrinter;
477

478
// Prints the given value using the << operator if it has one;
479
// otherwise prints the bytes in it.  This is what
480
// UniversalPrinter<T>::Print() does when PrintTo() is not specialized
481
// or overloaded for type T.
482
//
483
// A user can override this behavior for a class type Foo by defining
484
// an overload of PrintTo() in the namespace where Foo is defined.  We
485
// give the user this option as sometimes defining a << operator for
486
// Foo is not desirable (e.g. the coding style may prevent doing it,
487
// or there is already a << operator but it doesn't do what the user
488
// wants).
489
template <typename T>
490
void PrintTo(const T& value, ::std::ostream* os) {
491
  internal::PrintWithFallback(value, os);
492
}
493

494
// The following list of PrintTo() overloads tells
495
// UniversalPrinter<T>::Print() how to print standard types (built-in
496
// types, strings, plain arrays, and pointers).
497

498
// Overloads for various char types.
499
GTEST_API_ void PrintTo(unsigned char c, ::std::ostream* os);
500
GTEST_API_ void PrintTo(signed char c, ::std::ostream* os);
501
inline void PrintTo(char c, ::std::ostream* os) {
502
  // When printing a plain char, we always treat it as unsigned.  This
503
  // way, the output won't be affected by whether the compiler thinks
504
  // char is signed or not.
505
  PrintTo(static_cast<unsigned char>(c), os);
506
}
507

508
// Overloads for other simple built-in types.
509
inline void PrintTo(bool x, ::std::ostream* os) {
510
  *os << (x ? "true" : "false");
511
}
512

513
// Overload for wchar_t type.
514
// Prints a wchar_t as a symbol if it is printable or as its internal
515
// code otherwise and also as its decimal code (except for L'\0').
516
// The L'\0' char is printed as "L'\\0'". The decimal code is printed
517
// as signed integer when wchar_t is implemented by the compiler
518
// as a signed type and is printed as an unsigned integer when wchar_t
519
// is implemented as an unsigned type.
520
GTEST_API_ void PrintTo(wchar_t wc, ::std::ostream* os);
521

522
GTEST_API_ void PrintTo(char32_t c, ::std::ostream* os);
523
inline void PrintTo(char16_t c, ::std::ostream* os) {
524
  PrintTo(ImplicitCast_<char32_t>(c), os);
525
}
526
#ifdef __cpp_lib_char8_t
527
inline void PrintTo(char8_t c, ::std::ostream* os) {
528
  PrintTo(ImplicitCast_<char32_t>(c), os);
529
}
530
#endif
531

532
// gcc/clang __{u,}int128_t
533
#if defined(__SIZEOF_INT128__)
534
GTEST_API_ void PrintTo(__uint128_t v, ::std::ostream* os);
535
GTEST_API_ void PrintTo(__int128_t v, ::std::ostream* os);
536
#endif  // __SIZEOF_INT128__
537

538
// The default resolution used to print floating-point values uses only
539
// 6 digits, which can be confusing if a test compares two values whose
540
// difference lies in the 7th digit.  So we'd like to print out numbers
541
// in full precision.
542
// However if the value is something simple like 1.1, full will print a
543
// long string like 1.100000001 due to floating-point numbers not using
544
// a base of 10.  This routiune returns an appropriate resolution for a
545
// given floating-point number, that is, 6 if it will be accurate, or a
546
// max_digits10 value (full precision) if it won't,  for values between
547
// 0.0001 and one million.
548
// It does this by computing what those digits would be (by multiplying
549
// by an appropriate power of 10), then dividing by that power again to
550
// see if gets the original value back.
551
// A similar algorithm applies for values larger than one million; note
552
// that for those values, we must divide to get a six-digit number, and
553
// then multiply to possibly get the original value again.
554
template <typename FloatType>
555
int AppropriateResolution(FloatType val) {
556
  int full = std::numeric_limits<FloatType>::max_digits10;
557
  if (val < 0) val = -val;
558

559
#ifdef __GNUC__
560
#pragma GCC diagnostic push
561
#pragma GCC diagnostic ignored "-Wfloat-equal"
562
#endif
563
  if (val < 1000000) {
564
    FloatType mulfor6 = 1e10;
565
    // Without these static casts, the template instantiation for float would
566
    // fail to compile when -Wdouble-promotion is enabled, as the arithmetic and
567
    // comparison logic would promote floats to doubles.
568
    if (val >= static_cast<FloatType>(100000.0)) {  // 100,000 to 999,999
569
      mulfor6 = 1.0;
570
    } else if (val >= static_cast<FloatType>(10000.0)) {
571
      mulfor6 = 1e1;
572
    } else if (val >= static_cast<FloatType>(1000.0)) {
573
      mulfor6 = 1e2;
574
    } else if (val >= static_cast<FloatType>(100.0)) {
575
      mulfor6 = 1e3;
576
    } else if (val >= static_cast<FloatType>(10.0)) {
577
      mulfor6 = 1e4;
578
    } else if (val >= static_cast<FloatType>(1.0)) {
579
      mulfor6 = 1e5;
580
    } else if (val >= static_cast<FloatType>(0.1)) {
581
      mulfor6 = 1e6;
582
    } else if (val >= static_cast<FloatType>(0.01)) {
583
      mulfor6 = 1e7;
584
    } else if (val >= static_cast<FloatType>(0.001)) {
585
      mulfor6 = 1e8;
586
    } else if (val >= static_cast<FloatType>(0.0001)) {
587
      mulfor6 = 1e9;
588
    }
589
    if (static_cast<FloatType>(static_cast<int32_t>(
590
            val * mulfor6 + (static_cast<FloatType>(0.5)))) /
591
            mulfor6 ==
592
        val)
593
      return 6;
594
  } else if (val < static_cast<FloatType>(1e10)) {
595
    FloatType divfor6 = static_cast<FloatType>(1.0);
596
    if (val >= static_cast<FloatType>(1e9)) {  // 1,000,000,000 to 9,999,999,999
597
      divfor6 = 10000;
598
    } else if (val >=
599
               static_cast<FloatType>(1e8)) {  // 100,000,000 to 999,999,999
600
      divfor6 = 1000;
601
    } else if (val >=
602
               static_cast<FloatType>(1e7)) {  // 10,000,000 to 99,999,999
603
      divfor6 = 100;
604
    } else if (val >= static_cast<FloatType>(1e6)) {  // 1,000,000 to 9,999,999
605
      divfor6 = 10;
606
    }
607
    if (static_cast<FloatType>(static_cast<int32_t>(
608
            val / divfor6 + (static_cast<FloatType>(0.5)))) *
609
            divfor6 ==
610
        val)
611
      return 6;
612
  }
613
#ifdef __GNUC__
614
#pragma GCC diagnostic pop
615
#endif
616
  return full;
617
}
618

619
inline void PrintTo(float f, ::std::ostream* os) {
620
  auto old_precision = os->precision();
621
  os->precision(AppropriateResolution(f));
622
  *os << f;
623
  os->precision(old_precision);
624
}
625

626
inline void PrintTo(double d, ::std::ostream* os) {
627
  auto old_precision = os->precision();
628
  os->precision(AppropriateResolution(d));
629
  *os << d;
630
  os->precision(old_precision);
631
}
632

633
// Overloads for C strings.
634
GTEST_API_ void PrintTo(const char* s, ::std::ostream* os);
635
inline void PrintTo(char* s, ::std::ostream* os) {
636
  PrintTo(ImplicitCast_<const char*>(s), os);
637
}
638

639
// signed/unsigned char is often used for representing binary data, so
640
// we print pointers to it as void* to be safe.
641
inline void PrintTo(const signed char* s, ::std::ostream* os) {
642
  PrintTo(ImplicitCast_<const void*>(s), os);
643
}
644
inline void PrintTo(signed char* s, ::std::ostream* os) {
645
  PrintTo(ImplicitCast_<const void*>(s), os);
646
}
647
inline void PrintTo(const unsigned char* s, ::std::ostream* os) {
648
  PrintTo(ImplicitCast_<const void*>(s), os);
649
}
650
inline void PrintTo(unsigned char* s, ::std::ostream* os) {
651
  PrintTo(ImplicitCast_<const void*>(s), os);
652
}
653
#ifdef __cpp_lib_char8_t
654
// Overloads for u8 strings.
655
GTEST_API_ void PrintTo(const char8_t* s, ::std::ostream* os);
656
inline void PrintTo(char8_t* s, ::std::ostream* os) {
657
  PrintTo(ImplicitCast_<const char8_t*>(s), os);
658
}
659
#endif
660
// Overloads for u16 strings.
661
GTEST_API_ void PrintTo(const char16_t* s, ::std::ostream* os);
662
inline void PrintTo(char16_t* s, ::std::ostream* os) {
663
  PrintTo(ImplicitCast_<const char16_t*>(s), os);
664
}
665
// Overloads for u32 strings.
666
GTEST_API_ void PrintTo(const char32_t* s, ::std::ostream* os);
667
inline void PrintTo(char32_t* s, ::std::ostream* os) {
668
  PrintTo(ImplicitCast_<const char32_t*>(s), os);
669
}
670

671
// MSVC can be configured to define wchar_t as a typedef of unsigned
672
// short.  It defines _NATIVE_WCHAR_T_DEFINED when wchar_t is a native
673
// type.  When wchar_t is a typedef, defining an overload for const
674
// wchar_t* would cause unsigned short* be printed as a wide string,
675
// possibly causing invalid memory accesses.
676
#if !defined(_MSC_VER) || defined(_NATIVE_WCHAR_T_DEFINED)
677
// Overloads for wide C strings
678
GTEST_API_ void PrintTo(const wchar_t* s, ::std::ostream* os);
679
inline void PrintTo(wchar_t* s, ::std::ostream* os) {
680
  PrintTo(ImplicitCast_<const wchar_t*>(s), os);
681
}
682
#endif
683

684
// Overload for C arrays.  Multi-dimensional arrays are printed
685
// properly.
686

687
// Prints the given number of elements in an array, without printing
688
// the curly braces.
689
template <typename T>
690
void PrintRawArrayTo(const T a[], size_t count, ::std::ostream* os) {
691
  UniversalPrint(a[0], os);
692
  for (size_t i = 1; i != count; i++) {
693
    *os << ", ";
694
    UniversalPrint(a[i], os);
695
  }
696
}
697

698
// Overloads for ::std::string.
699
GTEST_API_ void PrintStringTo(const ::std::string& s, ::std::ostream* os);
700
inline void PrintTo(const ::std::string& s, ::std::ostream* os) {
701
  PrintStringTo(s, os);
702
}
703

704
// Overloads for ::std::u8string
705
#ifdef __cpp_lib_char8_t
706
GTEST_API_ void PrintU8StringTo(const ::std::u8string& s, ::std::ostream* os);
707
inline void PrintTo(const ::std::u8string& s, ::std::ostream* os) {
708
  PrintU8StringTo(s, os);
709
}
710
#endif
711

712
// Overloads for ::std::u16string
713
GTEST_API_ void PrintU16StringTo(const ::std::u16string& s, ::std::ostream* os);
714
inline void PrintTo(const ::std::u16string& s, ::std::ostream* os) {
715
  PrintU16StringTo(s, os);
716
}
717

718
// Overloads for ::std::u32string
719
GTEST_API_ void PrintU32StringTo(const ::std::u32string& s, ::std::ostream* os);
720
inline void PrintTo(const ::std::u32string& s, ::std::ostream* os) {
721
  PrintU32StringTo(s, os);
722
}
723

724
// Overloads for ::std::wstring.
725
#if GTEST_HAS_STD_WSTRING
726
GTEST_API_ void PrintWideStringTo(const ::std::wstring& s, ::std::ostream* os);
727
inline void PrintTo(const ::std::wstring& s, ::std::ostream* os) {
728
  PrintWideStringTo(s, os);
729
}
730
#endif  // GTEST_HAS_STD_WSTRING
731

732
#if GTEST_INTERNAL_HAS_STRING_VIEW
733
// Overload for internal::StringView.
734
inline void PrintTo(internal::StringView sp, ::std::ostream* os) {
735
  PrintTo(::std::string(sp), os);
736
}
737
#endif  // GTEST_INTERNAL_HAS_STRING_VIEW
738

739
inline void PrintTo(std::nullptr_t, ::std::ostream* os) { *os << "(nullptr)"; }
740

741
#if GTEST_HAS_RTTI
742
inline void PrintTo(const std::type_info& info, std::ostream* os) {
743
  *os << internal::GetTypeName(info);
744
}
745
#endif  // GTEST_HAS_RTTI
746

747
template <typename T>
748
void PrintTo(std::reference_wrapper<T> ref, ::std::ostream* os) {
749
  UniversalPrinter<T&>::Print(ref.get(), os);
750
}
751

752
inline const void* VoidifyPointer(const void* p) { return p; }
753
inline const void* VoidifyPointer(volatile const void* p) {
754
  return const_cast<const void*>(p);
755
}
756

757
template <typename T, typename Ptr>
758
void PrintSmartPointer(const Ptr& ptr, std::ostream* os, char) {
759
  if (ptr == nullptr) {
760
    *os << "(nullptr)";
761
  } else {
762
    // We can't print the value. Just print the pointer..
763
    *os << "(" << (VoidifyPointer)(ptr.get()) << ")";
764
  }
765
}
766
template <typename T, typename Ptr,
767
          typename = typename std::enable_if<!std::is_void<T>::value &&
768
                                             !std::is_array<T>::value>::type>
769
void PrintSmartPointer(const Ptr& ptr, std::ostream* os, int) {
770
  if (ptr == nullptr) {
771
    *os << "(nullptr)";
772
  } else {
773
    *os << "(ptr = " << (VoidifyPointer)(ptr.get()) << ", value = ";
774
    UniversalPrinter<T>::Print(*ptr, os);
775
    *os << ")";
776
  }
777
}
778

779
template <typename T, typename D>
780
void PrintTo(const std::unique_ptr<T, D>& ptr, std::ostream* os) {
781
  (PrintSmartPointer<T>)(ptr, os, 0);
782
}
783

784
template <typename T>
785
void PrintTo(const std::shared_ptr<T>& ptr, std::ostream* os) {
786
  (PrintSmartPointer<T>)(ptr, os, 0);
787
}
788

789
#if GTEST_INTERNAL_HAS_COMPARE_LIB
790
template <typename T>
791
void PrintOrderingHelper(T ordering, std::ostream* os) {
792
  if (ordering == T::less) {
793
    *os << "(less)";
794
  } else if (ordering == T::greater) {
795
    *os << "(greater)";
796
  } else if (ordering == T::equivalent) {
797
    *os << "(equivalent)";
798
  } else {
799
    *os << "(unknown ordering)";
800
  }
801
}
802

803
inline void PrintTo(std::strong_ordering ordering, std::ostream* os) {
804
  if (ordering == std::strong_ordering::equal) {
805
    *os << "(equal)";
806
  } else {
807
    PrintOrderingHelper(ordering, os);
808
  }
809
}
810

811
inline void PrintTo(std::partial_ordering ordering, std::ostream* os) {
812
  if (ordering == std::partial_ordering::unordered) {
813
    *os << "(unordered)";
814
  } else {
815
    PrintOrderingHelper(ordering, os);
816
  }
817
}
818

819
inline void PrintTo(std::weak_ordering ordering, std::ostream* os) {
820
  PrintOrderingHelper(ordering, os);
821
}
822
#endif
823

824
// Helper function for printing a tuple.  T must be instantiated with
825
// a tuple type.
826
template <typename T>
827
void PrintTupleTo(const T&, std::integral_constant<size_t, 0>,
828
                  ::std::ostream*) {}
829

830
template <typename T, size_t I>
831
void PrintTupleTo(const T& t, std::integral_constant<size_t, I>,
832
                  ::std::ostream* os) {
833
  PrintTupleTo(t, std::integral_constant<size_t, I - 1>(), os);
834
  GTEST_INTENTIONAL_CONST_COND_PUSH_()
835
  if (I > 1) {
836
    GTEST_INTENTIONAL_CONST_COND_POP_()
837
    *os << ", ";
838
  }
839
  UniversalPrinter<typename std::tuple_element<I - 1, T>::type>::Print(
840
      std::get<I - 1>(t), os);
841
}
842

843
template <typename... Types>
844
void PrintTo(const ::std::tuple<Types...>& t, ::std::ostream* os) {
845
  *os << "(";
846
  PrintTupleTo(t, std::integral_constant<size_t, sizeof...(Types)>(), os);
847
  *os << ")";
848
}
849

850
// Overload for std::pair.
851
template <typename T1, typename T2>
852
void PrintTo(const ::std::pair<T1, T2>& value, ::std::ostream* os) {
853
  *os << '(';
854
  // We cannot use UniversalPrint(value.first, os) here, as T1 may be
855
  // a reference type.  The same for printing value.second.
856
  UniversalPrinter<T1>::Print(value.first, os);
857
  *os << ", ";
858
  UniversalPrinter<T2>::Print(value.second, os);
859
  *os << ')';
860
}
861

862
// Implements printing a non-reference type T by letting the compiler
863
// pick the right overload of PrintTo() for T.
864
template <typename T>
865
class UniversalPrinter {
866
 public:
867
  // MSVC warns about adding const to a function type, so we want to
868
  // disable the warning.
869
  GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180)
870

871
  // Note: we deliberately don't call this PrintTo(), as that name
872
  // conflicts with ::testing::internal::PrintTo in the body of the
873
  // function.
874
  static void Print(const T& value, ::std::ostream* os) {
875
    // By default, ::testing::internal::PrintTo() is used for printing
876
    // the value.
877
    //
878
    // Thanks to Koenig look-up, if T is a class and has its own
879
    // PrintTo() function defined in its namespace, that function will
880
    // be visible here.  Since it is more specific than the generic ones
881
    // in ::testing::internal, it will be picked by the compiler in the
882
    // following statement - exactly what we want.
883
    PrintTo(value, os);
884
  }
885

886
  GTEST_DISABLE_MSC_WARNINGS_POP_()
887
};
888

889
// Remove any const-qualifiers before passing a type to UniversalPrinter.
890
template <typename T>
891
class UniversalPrinter<const T> : public UniversalPrinter<T> {};
892

893
#if GTEST_INTERNAL_HAS_ANY
894

895
// Printer for std::any / absl::any
896

897
template <>
898
class UniversalPrinter<Any> {
899
 public:
900
  static void Print(const Any& value, ::std::ostream* os) {
901
    if (value.has_value()) {
902
      *os << "value of type " << GetTypeName(value);
903
    } else {
904
      *os << "no value";
905
    }
906
  }
907

908
 private:
909
  static std::string GetTypeName(const Any& value) {
910
#if GTEST_HAS_RTTI
911
    return internal::GetTypeName(value.type());
912
#else
913
    static_cast<void>(value);  // possibly unused
914
    return "<unknown_type>";
915
#endif  // GTEST_HAS_RTTI
916
  }
917
};
918

919
#endif  // GTEST_INTERNAL_HAS_ANY
920

921
#if GTEST_INTERNAL_HAS_OPTIONAL
922

923
// Printer for std::optional / absl::optional
924

925
template <typename T>
926
class UniversalPrinter<Optional<T>> {
927
 public:
928
  static void Print(const Optional<T>& value, ::std::ostream* os) {
929
    *os << '(';
930
    if (!value) {
931
      *os << "nullopt";
932
    } else {
933
      UniversalPrint(*value, os);
934
    }
935
    *os << ')';
936
  }
937
};
938

939
template <>
940
class UniversalPrinter<decltype(Nullopt())> {
941
 public:
942
  static void Print(decltype(Nullopt()), ::std::ostream* os) {
943
    *os << "(nullopt)";
944
  }
945
};
946

947
#endif  // GTEST_INTERNAL_HAS_OPTIONAL
948

949
#if GTEST_INTERNAL_HAS_VARIANT
950

951
// Printer for std::variant / absl::variant
952

953
template <typename... T>
954
class UniversalPrinter<Variant<T...>> {
955
 public:
956
  static void Print(const Variant<T...>& value, ::std::ostream* os) {
957
    *os << '(';
958
#ifdef GTEST_HAS_ABSL
959
    absl::visit(Visitor{os, value.index()}, value);
960
#else
961
    std::visit(Visitor{os, value.index()}, value);
962
#endif  // GTEST_HAS_ABSL
963
    *os << ')';
964
  }
965

966
 private:
967
  struct Visitor {
968
    template <typename U>
969
    void operator()(const U& u) const {
970
      *os << "'" << GetTypeName<U>() << "(index = " << index
971
          << ")' with value ";
972
      UniversalPrint(u, os);
973
    }
974
    ::std::ostream* os;
975
    std::size_t index;
976
  };
977
};
978

979
#endif  // GTEST_INTERNAL_HAS_VARIANT
980

981
// UniversalPrintArray(begin, len, os) prints an array of 'len'
982
// elements, starting at address 'begin'.
983
template <typename T>
984
void UniversalPrintArray(const T* begin, size_t len, ::std::ostream* os) {
985
  if (len == 0) {
986
    *os << "{}";
987
  } else {
988
    *os << "{ ";
989
    const size_t kThreshold = 18;
990
    const size_t kChunkSize = 8;
991
    // If the array has more than kThreshold elements, we'll have to
992
    // omit some details by printing only the first and the last
993
    // kChunkSize elements.
994
    if (len <= kThreshold) {
995
      PrintRawArrayTo(begin, len, os);
996
    } else {
997
      PrintRawArrayTo(begin, kChunkSize, os);
998
      *os << ", ..., ";
999
      PrintRawArrayTo(begin + len - kChunkSize, kChunkSize, os);
1000
    }
1001
    *os << " }";
1002
  }
1003
}
1004
// This overload prints a (const) char array compactly.
1005
GTEST_API_ void UniversalPrintArray(const char* begin, size_t len,
1006
                                    ::std::ostream* os);
1007

1008
#ifdef __cpp_lib_char8_t
1009
// This overload prints a (const) char8_t array compactly.
1010
GTEST_API_ void UniversalPrintArray(const char8_t* begin, size_t len,
1011
                                    ::std::ostream* os);
1012
#endif
1013

1014
// This overload prints a (const) char16_t array compactly.
1015
GTEST_API_ void UniversalPrintArray(const char16_t* begin, size_t len,
1016
                                    ::std::ostream* os);
1017

1018
// This overload prints a (const) char32_t array compactly.
1019
GTEST_API_ void UniversalPrintArray(const char32_t* begin, size_t len,
1020
                                    ::std::ostream* os);
1021

1022
// This overload prints a (const) wchar_t array compactly.
1023
GTEST_API_ void UniversalPrintArray(const wchar_t* begin, size_t len,
1024
                                    ::std::ostream* os);
1025

1026
// Implements printing an array type T[N].
1027
template <typename T, size_t N>
1028
class UniversalPrinter<T[N]> {
1029
 public:
1030
  // Prints the given array, omitting some elements when there are too
1031
  // many.
1032
  static void Print(const T (&a)[N], ::std::ostream* os) {
1033
    UniversalPrintArray(a, N, os);
1034
  }
1035
};
1036

1037
// Implements printing a reference type T&.
1038
template <typename T>
1039
class UniversalPrinter<T&> {
1040
 public:
1041
  // MSVC warns about adding const to a function type, so we want to
1042
  // disable the warning.
1043
  GTEST_DISABLE_MSC_WARNINGS_PUSH_(4180)
1044

1045
  static void Print(const T& value, ::std::ostream* os) {
1046
    // Prints the address of the value.  We use reinterpret_cast here
1047
    // as static_cast doesn't compile when T is a function type.
1048
    *os << "@" << reinterpret_cast<const void*>(&value) << " ";
1049

1050
    // Then prints the value itself.
1051
    UniversalPrint(value, os);
1052
  }
1053

1054
  GTEST_DISABLE_MSC_WARNINGS_POP_()
1055
};
1056

1057
// Prints a value tersely: for a reference type, the referenced value
1058
// (but not the address) is printed; for a (const) char pointer, the
1059
// NUL-terminated string (but not the pointer) is printed.
1060

1061
template <typename T>
1062
class UniversalTersePrinter {
1063
 public:
1064
  static void Print(const T& value, ::std::ostream* os) {
1065
    UniversalPrint(value, os);
1066
  }
1067
};
1068
template <typename T>
1069
class UniversalTersePrinter<T&> {
1070
 public:
1071
  static void Print(const T& value, ::std::ostream* os) {
1072
    UniversalPrint(value, os);
1073
  }
1074
};
1075
template <typename T>
1076
class UniversalTersePrinter<std::reference_wrapper<T>> {
1077
 public:
1078
  static void Print(std::reference_wrapper<T> value, ::std::ostream* os) {
1079
    UniversalTersePrinter<T>::Print(value.get(), os);
1080
  }
1081
};
1082
template <typename T, size_t N>
1083
class UniversalTersePrinter<T[N]> {
1084
 public:
1085
  static void Print(const T (&value)[N], ::std::ostream* os) {
1086
    UniversalPrinter<T[N]>::Print(value, os);
1087
  }
1088
};
1089
template <>
1090
class UniversalTersePrinter<const char*> {
1091
 public:
1092
  static void Print(const char* str, ::std::ostream* os) {
1093
    if (str == nullptr) {
1094
      *os << "NULL";
1095
    } else {
1096
      UniversalPrint(std::string(str), os);
1097
    }
1098
  }
1099
};
1100
template <>
1101
class UniversalTersePrinter<char*> : public UniversalTersePrinter<const char*> {
1102
};
1103

1104
#ifdef __cpp_lib_char8_t
1105
template <>
1106
class UniversalTersePrinter<const char8_t*> {
1107
 public:
1108
  static void Print(const char8_t* str, ::std::ostream* os) {
1109
    if (str == nullptr) {
1110
      *os << "NULL";
1111
    } else {
1112
      UniversalPrint(::std::u8string(str), os);
1113
    }
1114
  }
1115
};
1116
template <>
1117
class UniversalTersePrinter<char8_t*>
1118
    : public UniversalTersePrinter<const char8_t*> {};
1119
#endif
1120

1121
template <>
1122
class UniversalTersePrinter<const char16_t*> {
1123
 public:
1124
  static void Print(const char16_t* str, ::std::ostream* os) {
1125
    if (str == nullptr) {
1126
      *os << "NULL";
1127
    } else {
1128
      UniversalPrint(::std::u16string(str), os);
1129
    }
1130
  }
1131
};
1132
template <>
1133
class UniversalTersePrinter<char16_t*>
1134
    : public UniversalTersePrinter<const char16_t*> {};
1135

1136
template <>
1137
class UniversalTersePrinter<const char32_t*> {
1138
 public:
1139
  static void Print(const char32_t* str, ::std::ostream* os) {
1140
    if (str == nullptr) {
1141
      *os << "NULL";
1142
    } else {
1143
      UniversalPrint(::std::u32string(str), os);
1144
    }
1145
  }
1146
};
1147
template <>
1148
class UniversalTersePrinter<char32_t*>
1149
    : public UniversalTersePrinter<const char32_t*> {};
1150

1151
#if GTEST_HAS_STD_WSTRING
1152
template <>
1153
class UniversalTersePrinter<const wchar_t*> {
1154
 public:
1155
  static void Print(const wchar_t* str, ::std::ostream* os) {
1156
    if (str == nullptr) {
1157
      *os << "NULL";
1158
    } else {
1159
      UniversalPrint(::std::wstring(str), os);
1160
    }
1161
  }
1162
};
1163
#endif
1164

1165
template <>
1166
class UniversalTersePrinter<wchar_t*> {
1167
 public:
1168
  static void Print(wchar_t* str, ::std::ostream* os) {
1169
    UniversalTersePrinter<const wchar_t*>::Print(str, os);
1170
  }
1171
};
1172

1173
template <typename T>
1174
void UniversalTersePrint(const T& value, ::std::ostream* os) {
1175
  UniversalTersePrinter<T>::Print(value, os);
1176
}
1177

1178
// Prints a value using the type inferred by the compiler.  The
1179
// difference between this and UniversalTersePrint() is that for a
1180
// (const) char pointer, this prints both the pointer and the
1181
// NUL-terminated string.
1182
template <typename T>
1183
void UniversalPrint(const T& value, ::std::ostream* os) {
1184
  // A workarond for the bug in VC++ 7.1 that prevents us from instantiating
1185
  // UniversalPrinter with T directly.
1186
  typedef T T1;
1187
  UniversalPrinter<T1>::Print(value, os);
1188
}
1189

1190
typedef ::std::vector<::std::string> Strings;
1191

1192
// Tersely prints the first N fields of a tuple to a string vector,
1193
// one element for each field.
1194
template <typename Tuple>
1195
void TersePrintPrefixToStrings(const Tuple&, std::integral_constant<size_t, 0>,
1196
                               Strings*) {}
1197
template <typename Tuple, size_t I>
1198
void TersePrintPrefixToStrings(const Tuple& t,
1199
                               std::integral_constant<size_t, I>,
1200
                               Strings* strings) {
1201
  TersePrintPrefixToStrings(t, std::integral_constant<size_t, I - 1>(),
1202
                            strings);
1203
  ::std::stringstream ss;
1204
  UniversalTersePrint(std::get<I - 1>(t), &ss);
1205
  strings->push_back(ss.str());
1206
}
1207

1208
// Prints the fields of a tuple tersely to a string vector, one
1209
// element for each field.  See the comment before
1210
// UniversalTersePrint() for how we define "tersely".
1211
template <typename Tuple>
1212
Strings UniversalTersePrintTupleFieldsToStrings(const Tuple& value) {
1213
  Strings result;
1214
  TersePrintPrefixToStrings(
1215
      value, std::integral_constant<size_t, std::tuple_size<Tuple>::value>(),
1216
      &result);
1217
  return result;
1218
}
1219

1220
}  // namespace internal
1221

1222
template <typename T>
1223
::std::string PrintToString(const T& value) {
1224
  ::std::stringstream ss;
1225
  internal::UniversalTersePrinter<T>::Print(value, &ss);
1226
  return ss.str();
1227
}
1228

1229
}  // namespace testing
1230

1231
// Include any custom printer added by the local installation.
1232
// We must include this header at the end to make sure it can use the
1233
// declarations from this file.
1234
#include "gtest/internal/custom/gtest-printers.h"
1235

1236
#endif  // GOOGLETEST_INCLUDE_GTEST_GTEST_PRINTERS_H_
1237

1238