Add test scaffolding

.clangd

@@ -0,0 +1,2 @@
+CompileFlags:
+  Add: [-DENABLE_TESTS]

CMakeLists.txt

@@ -8,3 +8,11 @@ set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 add_library(conflict_set ConflictSet.cpp ConflictSet.h)
+
+add_executable(conflict_set_test ConflictSet.cpp ConflictSet.h)
+target_compile_definitions(conflict_set_test PRIVATE ENABLE_TESTS)
+# keep asserts for test
+target_compile_options(conflict_set_test PRIVATE -UNDEBUG)
+
+include(CTest)
+add_test(NAME conflict_set_test COMMAND conflict_set_test)

ConflictSet.cpp

@@ -149,3 +149,7 @@ ConflictSet &ConflictSet::operator=(ConflictSet &&other) noexcept {
   impl = std::exchange(other.impl, nullptr);
   return *this;
 }
+
+#ifdef ENABLE_TESTS
+int main(void) { ConflictSet cs{0}; }
+#endif