Commit 72cd787e authored by Eric Fiselier's avatar Eric Fiselier
Browse files

Merge R292276: Fix std::string assignment ambiguity from braced initializer lists. 

When support for `basic_string_view` was added to string it also
added new assignment operators from `basic_string_view`. These caused
ambiguity when assigning from a braced initializer. This patch fixes
that regression by making the basic_string_view assignment operator
rank lower in overload resolution by making it a template.

llvm-svn: 292354
parent 5476b86e

libcxx/include/string

+1 −0
Original line number Diff line number Diff line
@@ -818,6 +818,7 @@ public: 
    operator __self_view() const _NOEXCEPT { return __self_view(data(), size()); }



    basic_string& operator=(const basic_string& __str);

    template <class = void>

    _LIBCPP_INLINE_VISIBILITY

    basic_string& operator=(__self_view __sv)  {return assign(__sv);}

#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES

libcxx/test/std/strings/basic.string/string.cons/brace_assignment.pass.cpp

0 → 100644
+36 −0
Original line number Diff line number Diff line 
//===----------------------------------------------------------------------===//

//

//                     The LLVM Compiler Infrastructure

//

// This file is dual licensed under the MIT and the University of Illinois Open

// Source Licenses. See LICENSE.TXT for details.

//

//===----------------------------------------------------------------------===//



// UNSUPPORTED: c++98, c++03



// <string>



// basic_string<charT,traits,Allocator>&

//   operator=(basic_string<charT,traits,Allocator>&& str);



#include <string>

#include <cassert>



#include "test_macros.h"



int main()

{

  // Test that assignment from {} and {ptr, len} are allowed and are not

  // ambiguous.

  {

    std::string s = "hello world";

    s = {};

    assert(s.empty());

  }

  {

    std::string s = "hello world";

    s = {"abc", 2};

    assert(s == "ab");

  }

}

libcxx/test/std/strings/basic.string/string.cons/string_view.pass.cpp

+22 −0
Original line number Diff line number Diff line
@@ -28,6 +28,7 @@ test(std::basic_string_view<charT> sv) 
    typedef std::basic_string<charT, std::char_traits<charT>, test_allocator<charT> > S;

    typedef typename S::traits_type T;

    typedef typename S::allocator_type A;

  {

    S s2(sv);

    LIBCPP_ASSERT(s2.__invariants());

    assert(s2.size() == sv.size());
@@ -35,6 +36,16 @@ test(std::basic_string_view<charT> sv) 
    assert(s2.get_allocator() == A());

    assert(s2.capacity() >= s2.size());

  }

  {

    S s2;

    s2 = sv;

    LIBCPP_ASSERT(s2.__invariants());

    assert(s2.size() == sv.size());

    assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);

    assert(s2.get_allocator() == A());

    assert(s2.capacity() >= s2.size());

  }

}



template <class charT, class A>

void
@@ -42,6 +53,7 @@ test(std::basic_string_view<charT> sv, const A& a) 
{

    typedef std::basic_string<charT, std::char_traits<charT>, A> S;

    typedef typename S::traits_type T;

  {

    S s2(sv, a);

    LIBCPP_ASSERT(s2.__invariants());

    assert(s2.size() == sv.size());
@@ -49,6 +61,16 @@ test(std::basic_string_view<charT> sv, const A& a) 
    assert(s2.get_allocator() == a);

    assert(s2.capacity() >= s2.size());

  }

  {

    S s2(a);

    s2 = sv;

    LIBCPP_ASSERT(s2.__invariants());

    assert(s2.size() == sv.size());

    assert(T::compare(s2.data(), sv.data(), sv.size()) == 0);

    assert(s2.get_allocator() == a);

    assert(s2.capacity() >= s2.size());

  }

}



int main()

{