#include <type_traits>
namespace llvm {
-template<class T, class V>
-typename std::enable_if< std::is_constructible<T, V>::value
- , typename std::remove_reference<V>::type>::type &&
- moveIfMoveConstructible(V &Val) {
- return std::move(Val);
-}
-
-template<class T, class V>
-typename std::enable_if< !std::is_constructible<T, V>::value
- , typename std::remove_reference<V>::type>::type &
-moveIfMoveConstructible(V &Val) {
- return Val;
-}
-
/// \brief Stores a reference that can be changed.
template <typename T>
class ReferenceStorage {
new (getErrorStorage()) std::error_code(EC);
}
- ErrorOr(T Val) : HasError(false) {
- new (getStorage()) storage_type(moveIfMoveConstructible<storage_type>(Val));
+ template <class OtherT>
+ ErrorOr(OtherT &&Val,
+ typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
+ * = nullptr)
+ : HasError(false) {
+ new (getStorage()) storage_type(std::forward<OtherT>(Val));
}
ErrorOr(const ErrorOr &Other) {
namespace {
-ErrorOr<int> t1() {return 1;}
+ErrorOr<int> t1() { return 1; }
ErrorOr<int> t2() { return errc::invalid_argument; }
TEST(ErrorOr, SimpleValue) {
EXPECT_EQ(x, errc::no_such_file_or_directory);
}
+TEST(ErrorOr, ImplicitConversion) {
+ ErrorOr<std::string> x("string literal");
+ EXPECT_TRUE(!!x);
+}
+
+TEST(ErrorOr, ImplicitConversionCausesMove) {
+ struct Source {};
+ struct Destination {
+ Destination(const Source&) {}
+ Destination(Source&&) = delete;
+ };
+ Source s;
+ ErrorOr<Destination> x = s;
+ EXPECT_TRUE(!!x);
+}
+
+TEST(ErrorOr, ImplicitConversionNoAmbiguity) {
+ struct CastsToErrorCode {
+ CastsToErrorCode() = default;
+ CastsToErrorCode(std::error_code) {}
+ operator std::error_code() { return errc::invalid_argument; }
+ } casts_to_error_code;
+ ErrorOr<CastsToErrorCode> x1(casts_to_error_code);
+ ErrorOr<CastsToErrorCode> x2 = casts_to_error_code;
+ ErrorOr<CastsToErrorCode> x3 = {casts_to_error_code};
+ ErrorOr<CastsToErrorCode> x4{casts_to_error_code};
+ ErrorOr<CastsToErrorCode> x5(errc::no_such_file_or_directory);
+ ErrorOr<CastsToErrorCode> x6 = errc::no_such_file_or_directory;
+ ErrorOr<CastsToErrorCode> x7 = {errc::no_such_file_or_directory};
+ ErrorOr<CastsToErrorCode> x8{errc::no_such_file_or_directory};
+ EXPECT_TRUE(!!x1);
+ EXPECT_TRUE(!!x2);
+ EXPECT_TRUE(!!x3);
+ EXPECT_TRUE(!!x4);
+ EXPECT_FALSE(x5);
+ EXPECT_FALSE(x6);
+ EXPECT_FALSE(x7);
+ EXPECT_FALSE(x8);
+}
+
// ErrorOr<int*> x(nullptr);
// ErrorOr<std::unique_ptr<int>> y = x; // invalid conversion
static_assert(