From 91533caf29a2c5b10b4912fd352e7af82c787598 Mon Sep 17 00:00:00 2001
From: Aina Niemetz <aina.niemetz@gmail.com>
Date: Wed, 16 Jun 2021 16:17:27 -0700
Subject: [PATCH] Configure google test as external project.

---
 CMakeLists.txt                  |  7 ----
 cmake/FindGoogleTest.cmake      | 60 +++++++++++++++++++++++++++++++++
 cmake/googletest-download.cmake | 28 ---------------
 cmake/googletest.cmake          | 41 ----------------------
 test/CMakeLists.txt             |  5 ++-
 5 files changed, 64 insertions(+), 77 deletions(-)
 create mode 100644 cmake/FindGoogleTest.cmake
 delete mode 100644 cmake/googletest-download.cmake
 delete mode 100644 cmake/googletest.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 38056ede6..d30475bcd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -440,13 +440,6 @@ configure_file(
 #-----------------------------------------------------------------------------#
 # Regression tests
 
-# Get and configure google test
-include(cmake/googletest.cmake)
-fetch_googletest(
-    ${PROJECT_SOURCE_DIR}/cmake
-    ${PROJECT_BINARY_DIR}/googletest
-    )
-
 enable_testing()
 
 #-----------------------------------------------------------------------------#
diff --git a/cmake/FindGoogleTest.cmake b/cmake/FindGoogleTest.cmake
new file mode 100644
index 000000000..c6eecd179
--- /dev/null
+++ b/cmake/FindGoogleTest.cmake
@@ -0,0 +1,60 @@
+# Boolector: Satisfiablity Modulo Theories (SMT) solver.
+#
+# Copyright (C) 2007-2021 by the authors listed in the AUTHORS file.
+#
+# This file is part of Boolector.
+# See COPYING for more information on using this software.
+#
+
+# Find GTest
+#
+# GTest_FOUND - Found GTest
+# GTest::GTest - GTest library
+
+find_package(GTest 1.10.0)
+
+if(NOT GTest_FOUND)
+  include(ExternalProject)
+
+  set(GTest_VERSION "1.10.0")
+
+  ExternalProject_Add(
+    GTest-EP
+    PREFIX "${CMAKE_BINARY_DIR}/deps"
+    URL https://github.com/google/googletest/archive/refs/tags/release-${GTest_VERSION}.tar.gz
+    URL_HASH SHA1=9c89be7df9c5e8cb0bc20b3c4b39bf7e82686770
+    DOWNLOAD_NAME gtest.tar.gz
+    CMAKE_ARGS
+      -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
+    BUILD_COMMAND ${CMAKE_COMMAND} --build .
+    BUILD_BYPRODUCTS
+        <INSTALL_DIR>/lib/libgtest.a
+        <INSTALL_DIR>/lib/libgtest_main.a
+    LOG_DOWNLOAD ON
+    LOG_UPDATE ON
+    LOG_CONFIGURE ON
+    LOG_BUILD ON
+    LOG_INSTALL ON
+    LOG_OUTPUT_ON_FAILURE TRUE
+  )
+
+  set(GTest_INCLUDE_DIR "${CMAKE_BINARY_DIR}/deps/include/")
+  set(GTest_MAIN_LIBRARY "${CMAKE_BINARY_DIR}/deps/lib/libgtest_main.a")
+  set(GTest_LIBRARY "${CMAKE_BINARY_DIR}/deps/lib/libgtest.a")
+  file(MAKE_DIRECTORY "${GTest_INCLUDE_DIR}")
+
+  add_library(GTest::gtest_main STATIC IMPORTED GLOBAL)
+  set_target_properties(GTest::gtest_main
+    PROPERTIES
+      IMPORTED_LOCATION "${GTest_MAIN_LIBRARY}"
+      INTERFACE_INCLUDE_DIRECTORIES "${GTest_INCLUDE_DIR}"
+      INTERFACE_LINK_LIBRARIES "${GTest_LIBRARY}"
+  )
+  set(GTest_FOUND TRUE)
+  add_dependencies(GTest::gtest_main GTest-EP)
+  message(STATUS "Building GTest ${GTest_VERSION}: ${GTest_MAIN_LIBRARY}")
+
+  mark_as_advanced(GTest_FOUND)
+  mark_as_advanced(GTest_INCLUDE_DIR)
+  mark_as_advanced(GTest_LIBRARIES)
+endif()
diff --git a/cmake/googletest-download.cmake b/cmake/googletest-download.cmake
deleted file mode 100644
index 8dca59539..000000000
--- a/cmake/googletest-download.cmake
+++ /dev/null
@@ -1,28 +0,0 @@
-# Boolector: Satisfiablity Modulo Theories (SMT) solver.
-#
-# Copyright (C) 2007-2021 by the authors listed in the AUTHORS file.
-#
-# This file is part of Boolector.
-# See COPYING for more information on using this software.
-#
-
-# code copied from https://crascit.com/2015/07/25/cmake-gtest/
-cmake_minimum_required(VERSION 3.5 FATAL_ERROR)
-
-project(googletest-download NONE)
-
-include(ExternalProject)
-
-ExternalProject_Add(
-  googletest
-  SOURCE_DIR "@GOOGLETEST_DOWNLOAD_ROOT@/googletest-src"
-  BINARY_DIR "@GOOGLETEST_DOWNLOAD_ROOT@/googletest-build"
-  GIT_REPOSITORY
-    https://github.com/google/googletest.git
-  GIT_TAG
-    release-1.10.0
-  CONFIGURE_COMMAND ""
-  BUILD_COMMAND ""
-  INSTALL_COMMAND ""
-  TEST_COMMAND ""
-  )
diff --git a/cmake/googletest.cmake b/cmake/googletest.cmake
deleted file mode 100644
index af5a5bc36..000000000
--- a/cmake/googletest.cmake
+++ /dev/null
@@ -1,41 +0,0 @@
-# Boolector: Satisfiablity Modulo Theories (SMT) solver.
-#
-# Copyright (C) 2007-2021 by the authors listed in the AUTHORS file.
-#
-# This file is part of Boolector.
-# See COPYING for more information on using this software.
-#
-
-# the following code to fetch googletest
-# is inspired by and adapted after https://crascit.com/2015/07/25/cmake-gtest/
-# download and unpack googletest at configure time
-
-macro(fetch_googletest _download_module_path _download_root)
-    set(GOOGLETEST_DOWNLOAD_ROOT ${_download_root})
-    configure_file(
-        ${_download_module_path}/googletest-download.cmake
-        ${_download_root}/CMakeLists.txt
-        @ONLY
-        )
-    unset(GOOGLETEST_DOWNLOAD_ROOT)
-
-    execute_process(
-        COMMAND
-            "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" .
-        WORKING_DIRECTORY
-            ${_download_root}
-        )
-    execute_process(
-        COMMAND
-            "${CMAKE_COMMAND}" --build .
-        WORKING_DIRECTORY
-            ${_download_root}
-        )
-
-    # adds the targers: gtest, gtest_main, gmock, gmock_main
-    add_subdirectory(
-        ${_download_root}/googletest-src
-        ${_download_root}/googletest-build
-        EXCLUDE_FROM_ALL
-        )
-endmacro()
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 13f87d5e0..f2e14fd81 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -5,6 +5,9 @@
 # This file is part of Boolector.
 # See COPYING for more information on using this software.
 #
+
+find_package(GoogleTest REQUIRED)
+
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin/tests)
 
 set(test_names
@@ -47,7 +50,7 @@ foreach(test ${test_names})
   add_executable (test${test} test_${test}.cpp)
   target_include_directories(test${test} PRIVATE ${PROJECT_SOURCE_DIR}/test/new_test)
   target_link_libraries(test${test} boolector m)
-  target_link_libraries(test${test} gtest_main)
+  target_link_libraries(test${test} GTest::gtest_main)
   set_target_properties(test${test} PROPERTIES OUTPUT_NAME test${test})
   add_test(${test} ${CMAKE_BINARY_DIR}/bin/tests/test${test})
 endforeach()