test: add google tests

CMakeLists.txt

@@ -7,11 +7,37 @@ project(
 
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
+# GoogleTest requires at least C++14
+set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+enable_testing()
+
 add_subdirectory(src/modules)
 
 add_executable(main src/main.cc)
+add_executable(test_validation src/test_validation.cc)
 add_library(validation src/validation.cc src/validation.hh)
 target_link_libraries(main PUBLIC validation)
-target_link_libraries(validation PUBLIC modules)
+target_link_libraries(validation PRIVATE modules)
+
 target_include_directories(main PUBLIC "${PROJECT_BINARY_DIR}"
                                        "${PROJECT_SOURCE_DIR}/modules")
+
+target_include_directories(
+  test_validation PUBLIC "${PROJECT_BINARY_DIR}"
+                         "${PROJECT_SOURCE_DIR}/modules")
+
+include(FetchContent)
+FetchContent_Declare(
+  googletest
+  URL https://github.com/google/googletest/archive/03597a01ee50ed33e9dfd640b249b4be3799d395.zip
+)
+# For Windows: Prevent overriding the parent project's compiler/linker settings
+set(gtest_force_shared_crt
+    ON
+    CACHE BOOL "" FORCE)
+FetchContent_MakeAvailable(googletest)
+
+include(GoogleTest)
+target_link_libraries(test_validation PRIVATE GTest::gtest_main)
+gtest_discover_tests(test_validation)

src/test_validation.cc

@@ -0,0 +1,10 @@
+#include "gtest/gtest.h"
+
+TEST(ExampleTest, Example) {
+    EXPECT_EQ(1, 1);
+}
+
+int main(int argc, char *argv[]) {
+    testing::InitGoogleTest(&argc, argv);
+    return RUN_ALL_TESTS();
+}