1 files changed, 89 insertions, 0 deletions
diff --git a/test/option.cc b/test/option.cc
new file mode 100644
index 0000000..8697089
--- /dev/null
+++ b/test/option.cc
@@ -0,0 +1,89 @@
+#include <option.h>
+#include <cstdlib>
+#include <cstdio>
+
+struct Checker {
+  static unsigned cnt;
+
+  Checker() {
+    ++cnt;
+  }
+  Checker(const Checker&) {
+    ++cnt;
+  }
+  Checker(Checker&&) {
+    ++cnt;
+  }
+  ~Checker() {
+    --cnt;
+  }
+};
+
+unsigned Checker::cnt = 0;
+
+int main() {
+  using option::option;
+
+  auto check_cnt = [](unsigned expect) {
+      if (expect != Checker::cnt) {
+          std::printf("Checker: expect=%u cnt=%u\n", expect, Checker::cnt);
+          std::abort();
+      }
+
+  };
+
+  {
+      option<int> o1;
+      option<int> o2{::option::none{}};
+
+      assert(!o1.has_value());
+      assert(!o2.has_value());
+  }
+
+  // Assume we start test with cnt=0.
+  check_cnt(0);
+
+  {
+      option<Checker> o1(Checker{});
+      // copy construct
+      option<Checker> o2 = o1;
+      // move construct
+      option<Checker> o3 = o1.take();
+
+      assert(!o1.has_value());
+      assert(o2.has_value());
+      assert(o3.has_value());
+
+      // move option
+      option<Checker> o4 = std::move(o2);
+
+      assert(!o2.has_value());
+      assert(o4.has_value());
+
+      // take reference to inner
+      auto x = o3.value();
+      // take ownership of inner
+      auto y = o4.take();
+
+      assert(!o1.has_value());
+      assert(!o2.has_value());
+      assert(o3.has_value());
+      assert(!o4.has_value());
+  }
+
+  // Expect to finish test with cnt=0.
+  check_cnt(0);
+
+  {
+      option<Checker> o1;
+      assert(!o1.has_value());
+
+      o1.emplace();
+      assert(o1.has_value());
+  }
+
+  // Expect to finish test with cnt=0.
+  check_cnt(0);
+
+  return 0;
+}