Googletest export

Merge b8ca465e73ac0954a0c9eec2a84bdd8913d5763b into 90a443f9c2437ca8a682a1ac625eba64e1d74a8a

Closes #2396

COPYBARA_INTEGRATE_REVIEW=https://github.com/google/googletest/pull/2396 from kuzkry:custom-type-traits-true/false_type-and-bool_constant b8ca465e73ac0954a0c9eec2a84bdd8913d5763b
PiperOrigin-RevId: 265064856

5 files changed, 29 insertions, 50 deletions

diff --git a/googlemock/include/gmock/gmock-matchers.h b/googlemock/include/gmock/gmock-matchers.h
index 5fe38205..b1c0dc04 100644
--- a/googlemock/include/gmock/gmock-matchers.h
+++ b/googlemock/include/gmock/gmock-matchers.h
@@ -132,19 +132,16 @@ class MatcherCastImpl {
     // polymorphic_matcher_or_value to Matcher<T> because it won't trigger
     // a user-defined conversion from M to T if one exists (assuming M is
     // a value).
-    return CastImpl(
-        polymorphic_matcher_or_value,
-        BooleanConstant<
-            std::is_convertible<M, Matcher<T> >::value>(),
-        BooleanConstant<
-            std::is_convertible<M, T>::value>());
+    return CastImpl(polymorphic_matcher_or_value,
+                    bool_constant<std::is_convertible<M, Matcher<T>>::value>(),
+                    bool_constant<std::is_convertible<M, T>::value>());
   }
 
  private:
   template <bool Ignore>
   static Matcher<T> CastImpl(const M& polymorphic_matcher_or_value,
-                             BooleanConstant<true> /* convertible_to_matcher */,
-                             BooleanConstant<Ignore>) {
+                             bool_constant<true> /* convertible_to_matcher */,
+                             bool_constant<Ignore>) {
     // M is implicitly convertible to Matcher<T>, which means that either
     // M is a polymorphic matcher or Matcher<T> has an implicit constructor
     // from M.  In both cases using the implicit conversion will produce a
@@ -159,9 +156,9 @@ class MatcherCastImpl {
   // M can't be implicitly converted to Matcher<T>, so M isn't a polymorphic
   // matcher. It's a value of a type implicitly convertible to T. Use direct
   // initialization to create a matcher.
-  static Matcher<T> CastImpl(
-      const M& value, BooleanConstant<false> /* convertible_to_matcher */,
-      BooleanConstant<true> /* convertible_to_T */) {
+  static Matcher<T> CastImpl(const M& value,
+                             bool_constant<false> /* convertible_to_matcher */,
+                             bool_constant<true> /* convertible_to_T */) {
     return Matcher<T>(ImplicitCast_<T>(value));
   }
 
@@ -175,9 +172,9 @@ class MatcherCastImpl {
   // (e.g. std::pair<const int, int> vs. std::pair<int, int>).
   //
   // We don't define this method inline as we need the declaration of Eq().
-  static Matcher<T> CastImpl(
-      const M& value, BooleanConstant<false> /* convertible_to_matcher */,
-      BooleanConstant<false> /* convertible_to_T */);
+  static Matcher<T> CastImpl(const M& value,
+                             bool_constant<false> /* convertible_to_matcher */,
+                             bool_constant<false> /* convertible_to_T */);
 };
 
 // This more specialized version is used when MatcherCast()'s argument
@@ -3603,9 +3600,8 @@ inline Matcher<T> An() { return A<T>(); }
 
 template <typename T, typename M>
 Matcher<T> internal::MatcherCastImpl<T, M>::CastImpl(
-    const M& value,
-    internal::BooleanConstant<false> /* convertible_to_matcher */,
-    internal::BooleanConstant<false> /* convertible_to_T */) {
+    const M& value, internal::bool_constant<false> /* convertible_to_matcher */,
+    internal::bool_constant<false> /* convertible_to_T */) {
   return Eq(value);
 }
 
diff --git a/googlemock/include/gmock/internal/gmock-internal-utils.h b/googlemock/include/gmock/internal/gmock-internal-utils.h
index 5386f48f..cea8ef6e 100644
--- a/googlemock/include/gmock/internal/gmock-internal-utils.h
+++ b/googlemock/include/gmock/internal/gmock-internal-utils.h
@@ -170,27 +170,27 @@ GMOCK_DECLARE_KIND_(long double, kFloatingPoint);
 // From, and kToKind is the kind of To; the value is
 // implementation-defined when the above pre-condition is violated.
 template <TypeKind kFromKind, typename From, TypeKind kToKind, typename To>
-struct LosslessArithmeticConvertibleImpl : public false_type {};
+struct LosslessArithmeticConvertibleImpl : public std::false_type {};
 
 // Converting bool to bool is lossless.
 template <>
 struct LosslessArithmeticConvertibleImpl<kBool, bool, kBool, bool>
-    : public true_type {};  // NOLINT
+    : public std::true_type {};
 
 // Converting bool to any integer type is lossless.
 template <typename To>
 struct LosslessArithmeticConvertibleImpl<kBool, bool, kInteger, To>
-    : public true_type {};  // NOLINT
+    : public std::true_type {};
 
 // Converting bool to any floating-point type is lossless.
 template <typename To>
 struct LosslessArithmeticConvertibleImpl<kBool, bool, kFloatingPoint, To>
-    : public true_type {};  // NOLINT
+    : public std::true_type {};
 
 // Converting an integer to bool is lossy.
 template <typename From>
 struct LosslessArithmeticConvertibleImpl<kInteger, From, kBool, bool>
-    : public false_type {};  // NOLINT
+    : public std::false_type {};
 
 // Converting an integer to another non-bool integer is lossless if
 // the target type's range encloses the source type's range.
@@ -211,17 +211,17 @@ struct LosslessArithmeticConvertibleImpl<kInteger, From, kInteger, To>
 // the format of a floating-point number is implementation-defined.
 template <typename From, typename To>
 struct LosslessArithmeticConvertibleImpl<kInteger, From, kFloatingPoint, To>
-    : public false_type {};  // NOLINT
+    : public std::false_type {};
 
 // Converting a floating-point to bool is lossy.
 template <typename From>
 struct LosslessArithmeticConvertibleImpl<kFloatingPoint, From, kBool, bool>
-    : public false_type {};  // NOLINT
+    : public std::false_type {};
 
 // Converting a floating-point to an integer is lossy.
 template <typename From, typename To>
 struct LosslessArithmeticConvertibleImpl<kFloatingPoint, From, kInteger, To>
-    : public false_type {};  // NOLINT
+    : public std::false_type {};
 
 // Converting a floating-point to another floating-point is lossless
 // if the target type is at least as big as the source type.
@@ -470,11 +470,6 @@ struct RemoveConstFromKey<std::pair<const K, V> > {
   typedef std::pair<K, V> type;
 };
 
-// Mapping from booleans to types. Similar to boost::bool_<kValue> and
-// std::integral_constant<bool, kValue>.
-template <bool kValue>
-struct BooleanConstant {};
-
 // Emit an assertion failure due to incorrect DoDefault() usage. Out-of-lined to
 // reduce code size.
 GTEST_API_ void IllegalDoDefault(const char* file, int line);
diff --git a/googlemock/test/gmock-internal-utils_test.cc b/googlemock/test/gmock-internal-utils_test.cc
index 67865c23..67b7077f 100644
--- a/googlemock/test/gmock-internal-utils_test.cc
+++ b/googlemock/test/gmock-internal-utils_test.cc
@@ -33,17 +33,20 @@
 // This file tests the internal utilities.
 
 #include "gmock/internal/gmock-internal-utils.h"
+
 #include <stdlib.h>
+
 #include <map>
 #include <memory>
-#include <string>
 #include <sstream>
+#include <string>
 #include <type_traits>
 #include <vector>
+
 #include "gmock/gmock.h"
 #include "gmock/internal/gmock-port.h"
-#include "gtest/gtest.h"
 #include "gtest/gtest-spi.h"
+#include "gtest/gtest.h"
 
 // Indicates that this translation unit is part of Google Test's
 // implementation.  It must come before gtest-internal-inl.h is
@@ -505,14 +508,6 @@ TEST(LogTest, OnlyWarningsArePrintedWhenVerbosityIsInvalid) {
 
 #endif  // GTEST_HAS_STREAM_REDIRECTION
 
-TEST(TypeTraitsTest, true_type) {
-  EXPECT_TRUE(true_type::value);
-}
-
-TEST(TypeTraitsTest, false_type) {
-  EXPECT_FALSE(false_type::value);
-}
-
 TEST(TypeTraitsTest, remove_reference) {
   EXPECT_TRUE((std::is_same<char, remove_reference<char&>::type>::value));
   EXPECT_TRUE(
diff --git a/googletest/include/gtest/internal/gtest-internal.h b/googletest/include/gtest/internal/gtest-internal.h
index 33134455..37daf214 100644
--- a/googletest/include/gtest/internal/gtest-internal.h
+++ b/googletest/include/gtest/internal/gtest-internal.h
@@ -946,7 +946,7 @@ template <typename C,
 struct IsRecursiveContainerImpl;
 
 template <typename C>
-struct IsRecursiveContainerImpl<C, false> : public false_type {};
+struct IsRecursiveContainerImpl<C, false> : public std::false_type {};
 
 // Since the IsRecursiveContainerImpl depends on the IsContainerTest we need to
 // obey the same inconsistencies as the IsContainerTest, namely check if
diff --git a/googletest/include/gtest/internal/gtest-port.h b/googletest/include/gtest/internal/gtest-port.h
index eaa19706..a637602c 100644
--- a/googletest/include/gtest/internal/gtest-port.h
+++ b/googletest/include/gtest/internal/gtest-port.h
@@ -1898,15 +1898,8 @@ class GTEST_API_ ThreadLocal {
 // we cannot detect it.
 GTEST_API_ size_t GetThreadCount();
 
-template <bool bool_value>
-struct bool_constant {
-  typedef bool_constant<bool_value> type;
-  static const bool value = bool_value;
-};
-template <bool bool_value> const bool bool_constant<bool_value>::value;
-
-typedef bool_constant<false> false_type;
-typedef bool_constant<true> true_type;
+template <bool B>
+using bool_constant = std::integral_constant<bool, B>;
 
 template <typename Iterator>
 struct IteratorTraits {