[libc++][NFC] Remove using declarations in common_reference.compile.pass.cpp

[philnik]

Summary

Remove using declarations in common_reference.compile.pass.cpp

[jloser]

LGTM

[Mordante]

LGTM, I like this cleanup.

[• Quuxplusone]

libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_reference.compile.pass.cpp

102–104

[philnik]

• Address comment

libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_reference.compile.pass.cpp

 // UNSUPPORTED: c++03, c++11, c++14, c++17
 // UNSUPPORTED: libcpp-no-concepts
 
 // type_traits
 // common_reference
 
 #include <type_traits>
 
-using std::common_reference;
-using std::common_reference_t;
-using std::is_same_v;
-using std::void_t;
-
 template <class T>
 constexpr bool has_type = requires {
   typename T::type;
 };
 
 // A slightly simplified variation of std::tuple
 template <class...>
 struct Tuple {};
 
 template <class, class, class>
 struct Tuple_helper {};
 template <class... Ts, class... Us>
-struct Tuple_helper<void_t<common_reference_t<Ts, Us>...>, Tuple<Ts...>,
-                    Tuple<Us...> > {
-  using type = Tuple<common_reference_t<Ts, Us>...>;
+struct Tuple_helper<std::void_t<std::common_reference_t<Ts, Us>...>, Tuple<Ts...>, Tuple<Us...> > {
+  using type = Tuple<std::common_reference_t<Ts, Us>...>;
 };
 
 namespace std {
-template <class... Ts, class... Us, template <class> class TQual,
-          template <class> class UQual>
+template <class... Ts, class... Us, template <class> class TQual, template <class> class UQual>
 struct basic_common_reference< ::Tuple<Ts...>, ::Tuple<Us...>, TQual, UQual>
     : ::Tuple_helper<void, Tuple<TQual<Ts>...>, Tuple<UQual<Us>...> > {};
 } // namespace std
 
 struct X2 {};
 struct Y2 {};
 struct Z2 {};
 
 namespace std {
 template <>
 struct common_type<X2, Y2> {
   using type = Z2;
 };
 template <>
 struct common_type<Y2, X2> {
   using type = Z2;
 };
 } // namespace std
 
 // (6.1)
 //  -- If sizeof...(T) is zero, there shall be no member type.
-static_assert(!has_type<common_reference<> >);
+static_assert(!has_type<std::common_reference<> >);
 
 // (6.2)
 //  -- Otherwise, if sizeof...(T) is one, let T0 denote the sole type in the
 //     pack T. The member typedef type shall denote the same type as T0.
-static_assert(is_same_v<common_reference_t<void>, void>);
-static_assert(is_same_v<common_reference_t<int>, int>);
-static_assert(is_same_v<common_reference_t<int&>, int&>);
-static_assert(is_same_v<common_reference_t<int&&>, int&&>);
-static_assert(is_same_v<common_reference_t<int const>, int const>);
-static_assert(is_same_v<common_reference_t<int const&>, int const&>);
-static_assert(is_same_v<common_reference_t<int const&&>, int const&&>);
-static_assert(is_same_v<common_reference_t<int volatile[]>, int volatile[]>);
-static_assert(
-    is_same_v<common_reference_t<int volatile (&)[]>, int volatile (&)[]>);
-static_assert(
-    is_same_v<common_reference_t<int volatile(&&)[]>, int volatile(&&)[]>);
-static_assert(is_same_v<common_reference_t<void (&)()>, void (&)()>);
-static_assert(is_same_v<common_reference_t<void(&&)()>, void(&&)()>);
+static_assert(std::is_same_v<std::common_reference_t<void>, void>);
+static_assert(std::is_same_v<std::common_reference_t<int>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int&>, int&>);
+static_assert(std::is_same_v<std::common_reference_t<int&&>, int&&>);
+static_assert(std::is_same_v<std::common_reference_t<int const>, int const>);
+static_assert(std::is_same_v<std::common_reference_t<int const&>, int const&>);
+static_assert(std::is_same_v<std::common_reference_t<int const&&>, int const&&>);
+static_assert(std::is_same_v<std::common_reference_t<int volatile[]>, int volatile[]>);
+static_assert(std::is_same_v<std::common_reference_t<int volatile (&)[]>, int volatile (&)[]>);
+static_assert(std::is_same_v<std::common_reference_t<int volatile (&&)[]>, int volatile (&&)[]>);
+static_assert(std::is_same_v<std::common_reference_t<void (&)()>, void (&)()>);
+static_assert(std::is_same_v<std::common_reference_t<void (&&)()>, void (&&)()>);
 
 // (6.3)
 //  -- Otherwise, if sizeof...(T) is two, let T1 and T2 denote the two types in
 //     the pack T. Then
 // (6.3.1)
 //    -- If T1 and T2 are reference types and COMMON_REF(T1, T2) is well-formed,
 //       then the member typedef type denotes that type.
 struct B {};
 struct D : B {};
-static_assert(is_same_v<common_reference_t<B&, D&>, B&>);
-static_assert(is_same_v<common_reference_t<B const&, D&>, B const&>);
-static_assert(is_same_v<common_reference_t<B&, D const&>, B const&>);
-static_assert(is_same_v<common_reference_t<B&, D const&, D&>, B const&>);
-static_assert(is_same_v<common_reference_t<B&, D&, B&, D&>, B&>);
-
-static_assert(is_same_v<common_reference_t<B&&, D&&>, B&&>);
-static_assert(is_same_v<common_reference_t<B const&&, D&&>, B const&&>);
-static_assert(is_same_v<common_reference_t<B&&, D const&&>, B const&&>);
-static_assert(is_same_v<common_reference_t<B&, D&&>, B const&>);
-static_assert(is_same_v<common_reference_t<B&, D const&&>, B const&>);
-static_assert(is_same_v<common_reference_t<B const&, D&&>, B const&>);
-
-static_assert(is_same_v<common_reference_t<B&&, D&>, B const&>);
-static_assert(is_same_v<common_reference_t<B&&, D const&>, B const&>);
-static_assert(is_same_v<common_reference_t<B const&&, D&>, B const&>);
-
-static_assert(
-    is_same_v<common_reference_t<int const volatile&&, int volatile&&>,
-              int const volatile&&>);
-
-static_assert(is_same_v<common_reference_t<int const&, int volatile&>,
-                        int const volatile&>);
-
-static_assert(
-    is_same_v<common_reference_t<int (&)[10], int(&&)[10]>, int const (&)[10]>);
-
-static_assert(
-    is_same_v<common_reference_t<int const (&)[10], int volatile (&)[10]>,
-              int const volatile (&)[10]>);
+static_assert(std::is_same_v<std::common_reference_t<B&, D&>, B&>);
+static_assert(std::is_same_v<std::common_reference_t<B const&, D&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B&, D const&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B&, D const&, D&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B&, D&, B&, D&>, B&>);
+
+static_assert(std::is_same_v<std::common_reference_t<B&&, D&&>, B&&>);
+static_assert(std::is_same_v<std::common_reference_t<B const&&, D&&>, B const&&>);
+static_assert(std::is_same_v<std::common_reference_t<B&&, D const&&>, B const&&>);
+static_assert(std::is_same_v<std::common_reference_t<B&, D&&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B&, D const&&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B const&, D&&>, B const&>);
+
+static_assert(std::is_same_v<std::common_reference_t<B&&, D&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B&&, D const&>, B const&>);
+static_assert(std::is_same_v<std::common_reference_t<B const&&, D&>, B const&>);
+
+static_assert(std::is_same_v<std::common_reference_t<int const&, int volatile&>, int const volatile&>);
+static_assert(std::is_same_v<std::common_reference_t<int const volatile&&, int volatile&&>, int const volatile&&>);
+
+static_assert(std::is_same_v<std::common_reference_t<int (&)[10], int (&&)[10]>, int const (&)[10]>);
+static_assert(std::is_same_v<std::common_reference_t<int const (&)[10], int volatile (&)[10]>, int const volatile (&)[10]>);
 
 // (6.3.2)
 //    -- Otherwise, if basic_common_reference<remove_cvref_t<T1>,
 //       remove_cvref_t<T2>, XREF(T1), XREF(T2)>::type is well-formed, then the
 //       member typedef type denotes that type.
-static_assert(is_same_v<common_reference_t<const Tuple<int, short>&,
-                                           Tuple<int&, short volatile&> >,
-                        Tuple<const int&, const volatile short&> >);
+static_assert(std::is_same_v<std::common_reference_t<const Tuple<int, short>&, Tuple<int&, short volatile&>>,
+                             Tuple<const int&, const volatile short&>>);
 
-static_assert(is_same_v<common_reference_t<volatile Tuple<int, short>&,
-                                           const Tuple<int, short>&>,
+static_assert(std::is_same_v<std::common_reference_t<volatile Tuple<int, short>&, const Tuple<int, short>&>,
                              const volatile Tuple<int, short>&>);
 
 // (6.3.3)
 //    -- Otherwise, if COND_RES(T1, T2) is well-formed, then the member typedef
 //       type denotes that type.
-static_assert(is_same_v<common_reference_t<void, void>, void>);
-static_assert(is_same_v<common_reference_t<int, short>, int>);
-static_assert(is_same_v<common_reference_t<int, short&>, int>);
-static_assert(is_same_v<common_reference_t<int&, short&>, int>);
-static_assert(is_same_v<common_reference_t<int&, short>, int>);
+static_assert(std::is_same_v<std::common_reference_t<void, void>, void>);
+static_assert(std::is_same_v<std::common_reference_t<int, short>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int, short&>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int&, short&>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int&, short>, int>);
 
 // tricky volatile reference case
-static_assert(is_same_v<common_reference_t<int&&, int volatile&>, int>);
-static_assert(is_same_v<common_reference_t<int volatile&, int&&>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int&&, int volatile&>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int volatile&, int&&>, int>);
 
-static_assert(is_same_v<common_reference_t<int (&)[10], int (&)[11]>, int*>);
+static_assert(std::is_same_v<std::common_reference_t<int (&)[10], int (&)[11]>, int*>);
 
 // https://github.com/ericniebler/stl2/issues/338
 struct MyIntRef {
   MyIntRef(int&);
 };
-static_assert(is_same_v<common_reference_t<int&, MyIntRef>, MyIntRef>);
+static_assert(std::is_same_v<std::common_reference_t<int&, MyIntRef>, MyIntRef>);
 
 // (6.3.4)
 //    -- Otherwise, if common_type_t<T1, T2> is well-formed, then the member
 //       typedef type denotes that type.
 struct moveonly {
   moveonly() = default;
   moveonly(moveonly&&) = default;
   moveonly& operator=(moveonly&&) = default;
 };
 struct moveonly2 : moveonly {};
 
-static_assert(
-    is_same_v<common_reference_t<moveonly const&, moveonly>, moveonly>);
-static_assert(
-    is_same_v<common_reference_t<moveonly2 const&, moveonly>, moveonly>);
-static_assert(
-    is_same_v<common_reference_t<moveonly const&, moveonly2>, moveonly>);
+static_assert(std::is_same_v<std::common_reference_t<moveonly const&, moveonly>, moveonly>);
+static_assert(std::is_same_v<std::common_reference_t<moveonly2 const&, moveonly>, moveonly>);
+static_assert(std::is_same_v<std::common_reference_t<moveonly const&, moveonly2>, moveonly>);
 
-static_assert(is_same_v<common_reference_t<X2&, Y2 const&>, Z2>);
+static_assert(std::is_same_v<std::common_reference_t<X2&, Y2 const&>, Z2>);
 
 // (6.3.5)
 //    -- Otherwise, there shall be no member type.
-static_assert(!has_type<common_reference<volatile Tuple<short>&,
-                                         const Tuple<int, short>&> >);
+static_assert(!has_type<std::common_reference<volatile Tuple<short>&, const Tuple<int, short>&> >);
 
 // (6.4)
 //  -- Otherwise, if sizeof...(T) is greater than two, let T1, T2, and Rest,
 //     respectively, denote the first, second, and (pack of) remaining types
 //     comprising T. Let C be the type common_reference_t<T1, T2>. Then:
 // (6.4.1)
 //    -- If there is such a type C, the member typedef type shall denote the
 //       same type, if any, as common_reference_t<C, Rest...>.
-static_assert(is_same_v<common_reference_t<int, int, int>, int>);
-static_assert(is_same_v<common_reference_t<int&&, int const&, int volatile&>,
-                        int const volatile&>);
-static_assert(is_same_v<common_reference_t<int&&, int const&, float&>, float>);
+static_assert(std::is_same_v<std::common_reference_t<int, int, int>, int>);
+static_assert(std::is_same_v<std::common_reference_t<int&&, int const&, int volatile&>, int const volatile&>);
+static_assert(std::is_same_v<std::common_reference_t<int&&, int const&, float&>, float>);
 
 // (6.4.2)
 //    -- Otherwise, there shall be no member type.
-static_assert(!has_type<common_reference<int, short, int, char*> >);
+static_assert(!has_type<std::common_reference<int, short, int, char*> >);
 
 int main(int, char**) { return 0; }