From f8fddac56b65ff8fd2f3e9b7b2ff25072cd13e92 Mon Sep 17 00:00:00 2001
From: Jeongseok Lee <jslee02@gmail.com>
Date: Sun, 7 Jul 2024 17:46:49 -0700
Subject: [PATCH] [build] Add DART_USE_SYSTEM_GOOGLETEST option

---
 CHANGELOG.md         |  3 +++
 CMakeLists.txt       |  1 +
 tests/CMakeLists.txt | 28 ++++++++++++++++------------
 3 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3265976c2718c..c08d6ec438bd5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,9 @@
   * macOS 14 / Clang 15 / arm64
   * Windows / MSVC 19.40 / x86_64
 
+* Build
+  * Added DART_USE_SYSTEM_GOOGLETEST option
+
 ### [DART 6.14.4 (TBD)](https://github.com/dartsim/dart/milestone/81?closed=1)
 
 * Tested Platforms
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 84c9c1c7b0fee..b0efc701fe04a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -99,6 +99,7 @@ dart_option(DART_FAST_DEBUG "Add -O1 option for DEBUG mode build" OFF)
 dart_option(DART_FORCE_COLORED_OUTPUT
   "Always produce ANSI-colored output (GNU/Clang only)." OFF)
 dart_option(DART_USE_SYSTEM_IMGUI "Use system ImGui" OFF)
+dart_option(DART_USE_SYSTEM_GOOGLETEST "Use system GoogleTest" OFF)
 
 #===============================================================================
 # Print intro
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 3e8bf1d65de7f..9cb838943e7ee 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -31,17 +31,21 @@
 #
 
 # Set up GoogleTest
-include(FetchContent)
-FetchContent_Declare(
-  googletest
-  GIT_REPOSITORY https://github.com/google/googletest
-  GIT_TAG v1.14.0
-)
-set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
-set(gtest_disable_pthreads ON CACHE BOOL "" FORCE)
-set(BUILD_GMOCK ON CACHE BOOL "" FORCE)
-set(INSTALL_GTEST OFF CACHE BOOL "" FORCE)
-FetchContent_MakeAvailable(googletest)
+if(DART_USE_SYSTEM_GOOGLETEST)
+  find_package(GTest MODULE REQUIRED)
+else()
+  include(FetchContent)
+  FetchContent_Declare(
+    googletest
+    GIT_REPOSITORY https://github.com/google/googletest
+    GIT_TAG v1.14.0
+  )
+  set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
+  set(gtest_disable_pthreads ON CACHE BOOL "" FORCE)
+  set(BUILD_GMOCK ON CACHE BOOL "" FORCE)
+  set(INSTALL_GTEST OFF CACHE BOOL "" FORCE)
+  FetchContent_MakeAvailable(googletest)
+end()
 
 #===============================================================================
 # This function uses following global properties:
@@ -65,7 +69,7 @@ function(dart_add_test test_type target_name) # ARGN for source files
 
   add_executable(${target_name} ${sources})
   add_test(${target_name} ${target_name})
-  target_link_libraries(${target_name} dart gtest gtest_main)
+  target_link_libraries(${target_name} dart GTest::gtest GTest::gtest_main)
 
   dart_format_add(${sources})