message: Add unit tests for is_comparable
diff: @@ -280,3 +280,31 @@ CAF_TEST(composed_types) {
  CAF_CHECK_EQUAL(dot_op(if_b, if_a), if_ba);
  CAF_CHECK_EQUAL(dot_op(if_b, if_c), if_bc);
  }
  +
  +struct foo {};
  +struct bar {};
  +bool operator==(const bar&, const bar&);
  +class baz {
  +public:
  + baz() = default;
  +
  + explicit baz(std::string);
  +
  + friend bool operator==(const baz&, const baz&);
  +
  +private:
  + std::string str_;
  +};
  +
  +CAF_TEST(is_comparable) {
  + CAF_CHECK((is_comparable<double, std::string>::value) == false);
  + CAF_CHECK((is_comparable<foo, foo>::value) == false);
  + CAF_CHECK((is_comparable<bar, bar>::value) == true);
  + CAF_CHECK((is_comparable<double, bar>::value) == false);
  + CAF_CHECK((is_comparable<bar, double>::value) == false);
  + CAF_CHECK((is_comparable<baz, baz>::value) == true);
  + CAF_CHECK((is_comparable<double, baz>::value) == false);
  + CAF_CHECK((is_comparable<baz, double>::value) == false);
  + CAF_CHECK((is_comparable<std::string, baz>::value) == false);
  + CAF_CHECK((is_comparable<baz, std::string>::value) == false);
  +}
  