gtest.cmake

# SPDX-License-Identifier: Apache-2.0
#
# Copyright (C) 2023 The Falco Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
# in compliance with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software distributed under the License
# is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
# or implied. See the License for the specific language governing permissions and limitations under
# the License.
#

option(USE_BUNDLED_GTEST "Enable building of the bundled gtest" ${USE_BUNDLED_DEPS})

if(GTEST_INCLUDE_DIR)
	# we already have gtest
elseif(NOT USE_BUNDLED_GTEST)
	find_path(
		GTEST_INCLUDE_DIR
		PATH_SUFFIXES gtest
		NAMES gtest.h
	)
	find_library(GTEST_LIB NAMES gtest)
	find_library(GTEST_MAIN_LIB NAMES gtest_main)
	if(GTEST_INCLUDE_DIR
	   AND GTEST_LIB
	   AND GTEST_MAIN_LIB
	)
		message(
			STATUS
				"Found gtest: include: ${GTEST_INCLUDE_DIR}, lib: ${GTEST_LIB}, main lib: ${GTEST_MAIN_LIB}"
		)
	else()
		message(FATAL_ERROR "Couldn't find system gtest")
	endif()
else()
	# https://github.com/google/googletest/tree/main/googletest#incorporating-into-an-existing-cmake-project
	# Download and unpack googletest at configure time
	configure_file(
		CMakeListsGtestInclude.cmake ${PROJECT_BINARY_DIR}/googletest-download/CMakeLists.txt
	)
	execute_process(
		COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
		RESULT_VARIABLE result
		WORKING_DIRECTORY ${PROJECT_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 ${PROJECT_BINARY_DIR}/googletest-download
	)
	if(result)
		message(FATAL_ERROR "Build step for googletest failed: ${result}")
	endif()

	# Add googletest directly to our build. This defines the gtest and gtest_main targets.
	add_subdirectory(
		${PROJECT_BINARY_DIR}/googletest-src ${PROJECT_BINARY_DIR}/googletest-build
		EXCLUDE_FROM_ALL
	)

	set(GTEST_INCLUDE_DIR "${gtest_SOURCE_DIR}/include")
	set(GTEST_MAIN_LIB "gtest_main")
	install(
		DIRECTORY "${GTEST_INCLUDE_DIR}"
		DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/${LIBS_PACKAGE_NAME}"
		COMPONENT "libs-deps"
	)
endif()

if(NOT TARGET gtest)
	add_custom_target(gtest)
endif()

include_directories("${GTEST_INCLUDE_DIR}")