Implement P0084r2. Changing emplace return types.

llvm-svn: 276230

9 files changed, 104 insertions, 80 deletions

diff --git a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
index 1d9c08b156b..77d822a0794 100644
--- a/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/queue/queue.defn/emplace.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <queue>
 
-// template <class... Args> void emplace(Args&&... args);
+// template <class... Args> reference emplace(Args&&... args);
 
 #include <queue>
 #include <cassert>
@@ -18,13 +20,17 @@
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+    typedef Emplaceable T;
     std::queue<Emplaceable> q;
-    q.emplace(1, 2.5);
-    q.emplace(2, 3.5);
-    q.emplace(3, 4.5);
+    T& r1 = q.emplace(1, 2.5);
+    assert(&r1 == &q.back());
+    T& r2 = q.emplace(2, 3.5);
+    assert(&r2 == &q.back());
+    T& r3 = q.emplace(3, 4.5);
+    assert(&r3 == &q.back());
     assert(q.size() == 3);
     assert(q.front() == Emplaceable(1, 2.5));
     assert(q.back() == Emplaceable(3, 4.5));
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+    assert(&r3 == &q.back());
+    assert(&r1 == &q.front());
 }
diff --git a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
index 3573c220ece..71fe903b74a 100644
--- a/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
+++ b/libcxx/test/std/containers/container.adaptors/stack/stack.defn/emplace.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <stack>
 
-// template <class... Args> void emplace(Args&&... args);
+// template <class... Args> reference emplace(Args&&... args);
 
 #include <stack>
 #include <cassert>
@@ -18,12 +20,14 @@
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+    typedef Emplaceable T;
     std::stack<Emplaceable> q;
-    q.emplace(1, 2.5);
-    q.emplace(2, 3.5);
-    q.emplace(3, 4.5);
+    T& r1 = q.emplace(1, 2.5);
+    assert(&r1 == &q.top());
+    T& r2 = q.emplace(2, 3.5);
+    assert(&r2 == &q.top());
+    T& r3 = q.emplace(3, 4.5);
+    assert(&r3 == &q.top());
     assert(q.size() == 3);
     assert(q.top() == Emplaceable(3, 4.5));
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
index 784b3a38553..f81cdf90419 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_back.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <deque>
 
-// template <class... Args> void emplace_back(Args&&... args);
+// template <class... Args> reference emplace_back(Args&&... args);
 
 #include <deque>
 #include <cassert>
@@ -18,8 +20,6 @@
 #include "min_allocator.h"
 #include "test_allocator.h"
 
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 template <class C>
 C
 make(int size, int start = 0 )
@@ -47,12 +47,14 @@ void
 test(C& c1)
 {
     typedef typename C::iterator I;
+    typedef typename C::reference Ref;
     std::size_t c1_osize = c1.size();
-    c1.emplace_back(Emplaceable(1, 2.5));
+    Ref ref = c1.emplace_back(Emplaceable(1, 2.5));
     assert(c1.size() == c1_osize + 1);
     assert(distance(c1.begin(), c1.end()) == c1.size());
     I i = c1.end();
     assert(*--i == Emplaceable(1, 2.5));
+    assert(&(*i) == &ref);
 }
 
 template <class C>
@@ -63,11 +65,8 @@ testN(int start, int N)
     test(c1);
 }
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
     const int N = sizeof(rng)/sizeof(rng[0]);
@@ -75,7 +74,6 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<Emplaceable> >(rng[i], rng[j]);
     }
-#if TEST_STD_VER >= 11
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
     const int N = sizeof(rng)/sizeof(rng[0]);
@@ -94,6 +92,4 @@ int main()
         c.emplace_front(1, 2, 3);
         assert(c.size() == 4);
     }
-#endif
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }
diff --git a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
index afc0e4972e3..668062d4af3 100644
--- a/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/deque/deque.modifiers/emplace_front.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <deque>
 
-// template <class... Args> void emplace_front(Args&&... args);
+// template <class... Args> reference emplace_front(Args&&... args);
 
 #include <deque>
 #include <cassert>
@@ -17,8 +19,6 @@
 #include "../../../Emplaceable.h"
 #include "min_allocator.h"
 
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 template <class C>
 C
 make(int size, int start = 0 )
@@ -46,12 +46,14 @@ void
 test(C& c1)
 {
     typedef typename C::iterator I;
+    typedef typename C::reference Ref;
     std::size_t c1_osize = c1.size();
-    c1.emplace_front(Emplaceable(1, 2.5));
+    Ref res_ref = c1.emplace_front(Emplaceable(1, 2.5));
     assert(c1.size() == c1_osize + 1);
     assert(distance(c1.begin(), c1.end()) == c1.size());
     I i = c1.begin();
     assert(*i == Emplaceable(1, 2.5));
+    assert(&res_ref == &(*i));
 }
 
 template <class C>
@@ -62,11 +64,9 @@ testN(int start, int N)
     test(c1);
 }
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
     const int N = sizeof(rng)/sizeof(rng[0]);
@@ -74,7 +74,6 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<Emplaceable> >(rng[i], rng[j]);
     }
-#if TEST_STD_VER >= 11
     {
     int rng[] = {0, 1, 2, 3, 1023, 1024, 1025, 2047, 2048, 2049};
     const int N = sizeof(rng)/sizeof(rng[0]);
@@ -82,6 +81,4 @@ int main()
         for (int j = 0; j < N; ++j)
             testN<std::deque<Emplaceable, min_allocator<Emplaceable>> >(rng[i], rng[j]);
     }
-#endif
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }
diff --git a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
index 18ed69d33f0..589e71894b8 100644
--- a/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/forwardlist/forwardlist.modifiers/emplace_front.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <forward_list>
 
-// template <class... Args> void emplace_front(Args&&... args);
+// template <class... Args> reference emplace_front(Args&&... args);
 
 #include <forward_list>
 #include <cassert>
@@ -19,32 +21,32 @@
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     {
         typedef Emplaceable T;
         typedef std::forward_list<T> C;
         C c;
-        c.emplace_front();
+        T& r1 = c.emplace_front();
         assert(c.front() == Emplaceable());
+        assert(&r1 == &c.front());
         assert(distance(c.begin(), c.end()) == 1);
-        c.emplace_front(1, 2.5);
+        T& r2 = c.emplace_front(1, 2.5);
         assert(c.front() == Emplaceable(1, 2.5));
+        assert(&r2 == &c.front());
         assert(*next(c.begin()) == Emplaceable());
         assert(distance(c.begin(), c.end()) == 2);
     }
-#if TEST_STD_VER >= 11
     {
         typedef Emplaceable T;
         typedef std::forward_list<T, min_allocator<T>> C;
         C c;
-        c.emplace_front();
+        T& r1 = c.emplace_front();
         assert(c.front() == Emplaceable());
+        assert(&r1 == &c.front());
         assert(distance(c.begin(), c.end()) == 1);
-        c.emplace_front(1, 2.5);
+        T& r2 = c.emplace_front(1, 2.5);
         assert(c.front() == Emplaceable(1, 2.5));
+        assert(&r2 == &c.front());
         assert(*next(c.begin()) == Emplaceable());
         assert(distance(c.begin(), c.end()) == 2);
     }
-#endif
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
index 2ff01f1676f..2aae2b9b09e 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_back.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <list>
 
-// template <class... Args> void emplace_back(Args&&... args);
+// template <class... Args> reference emplace_back(Args&&... args);
 
 #include <list>
 #include <cassert>
@@ -33,34 +35,34 @@ public:
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     {
     std::list<A> c;
-    c.emplace_back(2, 3.5);
+    A& r1 = c.emplace_back(2, 3.5);
     assert(c.size() == 1);
+    assert(&r1 == &c.back());
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
-    c.emplace_back(3, 4.5);
+    A& r2 = c.emplace_back(3, 4.5);
     assert(c.size() == 2);
+    assert(&r2 == &c.back());
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
     assert(c.back().geti() == 3);
     assert(c.back().getd() == 4.5);
     }
-#if TEST_STD_VER >= 11
     {
     std::list<A, min_allocator<A>> c;
-    c.emplace_back(2, 3.5);
+    A& r1 = c.emplace_back(2, 3.5);
     assert(c.size() == 1);
+    assert(&r1 == &c.back());
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
-    c.emplace_back(3, 4.5);
+    A& r2 = c.emplace_back(3, 4.5);
     assert(c.size() == 2);
+    assert(&r2 == &c.back());
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
     assert(c.back().geti() == 3);
     assert(c.back().getd() == 4.5);
     }
-#endif
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }
diff --git a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
index 8a3df46a31e..994dac258f8 100644
--- a/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
+++ b/libcxx/test/std/containers/sequences/list/list.modifiers/emplace_front.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <list>
 
-// template <class... Args> void emplace_front(Args&&... args);
+// template <class... Args> reference emplace_front(Args&&... args);
 
 #include <list>
 #include <cassert>
@@ -33,34 +35,34 @@ public:
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     {
     std::list<A> c;
-    c.emplace_front(2, 3.5);
+    A& r1 = c.emplace_front(2, 3.5);
     assert(c.size() == 1);
+    assert(&r1 == &c.front());
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
-    c.emplace_front(3, 4.5);
+    A& r2 = c.emplace_front(3, 4.5);
     assert(c.size() == 2);
+    assert(&r2 == &c.front());
     assert(c.front().geti() == 3);
     assert(c.front().getd() == 4.5);
     assert(c.back().geti() == 2);
     assert(c.back().getd() == 3.5);
     }
-#if TEST_STD_VER >= 11
     {
     std::list<A, min_allocator<A>> c;
-    c.emplace_front(2, 3.5);
+    A& r1 = c.emplace_front(2, 3.5);
     assert(c.size() == 1);
+    assert(&r1 == &c.front());
     assert(c.front().geti() == 2);
     assert(c.front().getd() == 3.5);
-    c.emplace_front(3, 4.5);
+    A& r2 = c.emplace_front(3, 4.5);
     assert(c.size() == 2);
+    assert(&r2 == &c.front());
     assert(c.front().geti() == 3);
     assert(c.front().getd() == 4.5);
     assert(c.back().geti() == 2);
     assert(c.back().getd() == 3.5);
     }
-#endif
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
index 2950ee3882f..24005bec82d 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
@@ -11,42 +11,57 @@
 // <vector>
 //  vector.bool
 
-// template <class... Args> void emplace_back(Args&&... args);
+// template <class... Args> reference emplace_back(Args&&... args);
 
 #include <vector>
 #include <cassert>
 #include "min_allocator.h"
 
-
 int main()
 {
     {
         typedef std::vector<bool> C;
+        typedef C::reference Ref;
         C c;
-        c.emplace_back();
+        Ref r1 = c.emplace_back();
         assert(c.size() == 1);
         assert(c.front() == false);
-        c.emplace_back(true);
+        r1 = true;
+        assert(c.front() == true);
+        r1 = false;
+        Ref r2 = c.emplace_back(true);
         assert(c.size() == 2);
         assert(c.front() == false);
         assert(c.back() == true);
-        c.emplace_back(1 == 1);
+        r2 = false;
+        assert(c.back() == false);
+        r2 = true;
+        Ref r3 = c.emplace_back(1 == 1);
         assert(c.size() == 3);
         assert(c.front() == false);
         assert(c[1] == true);
         assert(c.back() == true);
+        r3 = false;
+        assert(c.back() == false);
     }
     {
         typedef std::vector<bool, min_allocator<bool>> C;
+        typedef C::reference Ref;
         C c;
 
-        c.emplace_back();
+        Ref r1 = c.emplace_back();
         assert(c.size() == 1);
         assert(c.front() == false);
-        c.emplace_back(true);
+        r1 = true;
+        assert(c.front() == true);
+        r1 = false;
+        Ref r2 = c.emplace_back(true);
         assert(c.size() == 2);
         assert(c.front() == false);
         assert(c.back() == true);
+        r2 = false;
+        assert(c.back() == false);
+        r2 = true;
         c.emplace_back(1 == 1);
         assert(c.size() == 3);
         assert(c.front() == false);
diff --git a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
index 61ccade76b0..6b435484d01 100644
--- a/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector/vector.modifiers/emplace_back.pass.cpp
@@ -7,9 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+// UNSUPPORTED: c++98, c++03
+
 // <vector>
 
-// template <class... Args> void emplace_back(Args&&... args);
+// template <class... Args> reference emplace_back(Args&&... args);
 
 #include <vector>
 #include <cassert>
@@ -18,8 +20,6 @@
 #include "test_allocator.h"
 #include "asan_testing.h"
 
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 class A
 {
     int i_;
@@ -52,20 +52,19 @@ public:
     double getd() const {return d_;}
 };
 
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
-
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
     {
         std::vector<A> c;
-        c.emplace_back(2, 3.5);
+        A& r1 = c.emplace_back(2, 3.5);
         assert(c.size() == 1);
+        assert(&r1 == &c.back());
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(is_contiguous_container_asan_correct(c));
-        c.emplace_back(3, 4.5);
+        A& r2 = c.emplace_back(3, 4.5);
         assert(c.size() == 2);
+        assert(&r2 == &c.back());
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(c.back().geti() == 3);
@@ -74,29 +73,32 @@ int main()
     }
     {
         std::vector<A, stack_allocator<A, 4> > c;
-        c.emplace_back(2, 3.5);
+        A& r1 = c.emplace_back(2, 3.5);
         assert(c.size() == 1);
+        assert(&r1 == &c.back());
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(is_contiguous_container_asan_correct(c));
-        c.emplace_back(3, 4.5);
+        A& r2 = c.emplace_back(3, 4.5);
         assert(c.size() == 2);
+        assert(&r2 == &c.back());
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(c.back().geti() == 3);
         assert(c.back().getd() == 4.5);
         assert(is_contiguous_container_asan_correct(c));
     }
-#if TEST_STD_VER >= 11
     {
         std::vector<A, min_allocator<A>> c;
-        c.emplace_back(2, 3.5);
+        A& r1 = c.emplace_back(2, 3.5);
         assert(c.size() == 1);
+        assert(&r1 == &c.back());
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(is_contiguous_container_asan_correct(c));
-        c.emplace_back(3, 4.5);
+        A& r2 = c.emplace_back(3, 4.5);
         assert(c.size() == 2);
+        assert(&r2 == &c.back());
         assert(c.front().geti() == 2);
         assert(c.front().getd() == 3.5);
         assert(c.back().geti() == 3);
@@ -111,6 +113,4 @@ int main()
         assert(c.size() == 2);
         assert(is_contiguous_container_asan_correct(c));
     }
-#endif
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 }