Use FetchContent to build googletest

CMakeLists.txt

@@ -331,34 +331,14 @@ set(ZSTD_LIBRARY_DEBUG
 
 if(WITH_TESTS)
   if(NOT PREFER_SYSTEM_GTEST)
-    # Download and unpack googletest at configure time
-    configure_file(CMakeLists.txt.gtest googletest-download/CMakeLists.txt)
-    execute_process(
-      COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
-      RESULT_VARIABLE result
-      WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/googletest-download)
-    if(result)
-      message(FATAL_ERROR "CMake step for googletest failed: ${result}")
-    endif()
-    execute_process(
-      COMMAND ${CMAKE_COMMAND} --build .
-      RESULT_VARIABLE result
-      WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/googletest-download)
-    if(result)
-      message(FATAL_ERROR "Build step for googletest failed: ${result}")
-    endif()
-
-    # Prevent overriding the parent project's compiler/linker settings on
-    # Windows
-    set(gtest_force_shared_crt
-        ON
-        CACHE BOOL "" FORCE)
-
-    # Add googletest directly to our build. This defines the gtest and
-    # gtest_main targets.
-    add_subdirectory(
-      ${CMAKE_CURRENT_BINARY_DIR}/googletest-src
-      ${CMAKE_CURRENT_BINARY_DIR}/googletest-build EXCLUDE_FROM_ALL SYSTEM)
+    include(FetchContent)
+    FetchContent_Declare(
+      googletest
+      URL https://github.com/google/googletest/archive/refs/tags/v1.13.0.zip
+    )
+    # For Windows: Prevent overriding the parent project's compiler/linker settings
+    set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
+    FetchContent_MakeAvailable(googletest)
   endif()
 
   enable_testing()

CMakeLists.txt.gtest

@@ -1,21 +0,0 @@
-cmake_minimum_required(VERSION 2.8.11)
-
-project(googletest-download NONE)
-
-include(ExternalProject)
-
-ExternalProject_Add(
-  googletest
-  GIT_REPOSITORY    ${GOOGLETEST_GIT_REPO}
-  GIT_TAG           main
-  PREFIX            "${CMAKE_CURRENT_BINARY_DIR}/googletest"
-  SOURCE_DIR        "${CMAKE_CURRENT_BINARY_DIR}/googletest-src"
-  BINARY_DIR        "${CMAKE_CURRENT_BINARY_DIR}/googletest-build"
-  CMAKE_ARGS        -DCMAKE_C_COMPILER_LAUNCHER=${CMAKE_C_COMPILER_LAUNCHER}
-                    -DCMAKE_CXX_COMPILER_LAUNCHER=${CMAKE_CXX_COMPILER_LAUNCHER}
-                    -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
-  CONFIGURE_COMMAND ""
-  BUILD_COMMAND     ""
-  INSTALL_COMMAND   ""
-  TEST_COMMAND      ""
-)