gtest dependency (#2163)

Allow gtest to be external dependency, see also #1731

CMakeLists.txt

@@ -238,6 +238,7 @@ install(FILES mechanisms/BuildModules.cmake DESTINATION ${ARB_INSTALL_DATADIR})
 
 cmake_dependent_option(ARB_USE_BUNDLED_FMT "Use bundled FMT lib." ON "ARB_USE_BUNDLED_LIBS" OFF)
 cmake_dependent_option(ARB_USE_BUNDLED_PUGIXML "Use bundled XML lib." ON "ARB_USE_BUNDLED_LIBS" OFF)
+cmake_dependent_option(ARB_USE_BUNDLED_GTEST "Use bundled GoogleTest." ON "ARB_USE_BUNDLED_LIBS" OFF)
 
 cmake_dependent_option(ARB_USE_BUNDLED_JSON "Use bundled Niels Lohmann's json library." ON "ARB_USE_BUNDLED_LIBS" OFF)
 if(NOT ARB_USE_BUNDLED_JSON)

ext/CMakeLists.txt

@@ -92,18 +92,29 @@ add_external_cmake_project(
 
 # Google Test framework:
 
-# Set up google test as an external project.
-add_external_cmake_project(
- NAME googletest
- INTERFACE_NAME ext-gtest
- LIB libgtest.a
- CMAKE_ARGS
- "-DCMAKE_BUILD_TYPE=release"
- "-DBUILD_SHARED_LIBS=OFF"
- "-DBUILD_GMOCK=OFF")
-
-# on some systems we need link explicitly against threads
-if (TARGET ext-gtest)
- find_package (Threads)
- target_link_libraries(ext-gtest INTERFACE Threads::Threads)
+if (ARB_USE_BUNDLED_GTEST)
+ # Set up google test as an external project.
+ add_external_cmake_project(
+ NAME googletest
+ INTERFACE_NAME ext-gtest
+ LIB libgtest.a
+ CMAKE_ARGS
+ "-DCMAKE_BUILD_TYPE=release"
+ "-DBUILD_SHARED_LIBS=OFF"
+ "-DBUILD_GMOCK=OFF")
+
+ # on some systems we need link explicitly against threads
+ if (TARGET ext-gtest)
+ find_package (Threads)
+ target_link_libraries(ext-gtest INTERFACE Threads::Threads)
+ endif()
+else()
+ # Use system provided google test
+ find_package(GTest)
+ add_library(ext-gtest INTERFACE)
+ if (${CMAKE_VERSION} VERSION_LESS "3.20.0")
+ target_link_libraries(ext-gtest INTERFACE GTest::GTest GTest::Main)
+ else()
+ target_link_libraries(ext-gtest INTERFACE GTest::gtest GTest::gtest_main)
+ endif()
 endif()

spack/package.py

@@ -82,7 +82,7 @@ class Arbor(CMakePackage, CudaPackage):
  # misc dependencies
  depends_on("[email protected]:", when="@0.5.3:") # required by the modcc compiler
  depends_on("[email protected]:", when="@0.7.1:")
- depends_on("[email protected]", type="test", when="@0.7.1:")
+ depends_on("[email protected]", when="@0.7.1:")
  depends_on("[email protected]:", when="@0.7.1:")
  depends_on("nlohmann-json")
  depends_on("random123")