1 files changed, 71 insertions, 0 deletions

diff --git a/test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp b/test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp
index 4c2d5112d10b..9e48cbf1e7f2 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp
+++ b/test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp
@@ -23,6 +23,7 @@
 
 #include <experimental/filesystem>
 #include <type_traits>
+#include <string_view>
 #include <cassert>
 
 #include "test_macros.h"
@@ -69,6 +70,32 @@ void RunTestCase(MultiStringType const& MS) {
     assert(p.string<CharT>() == TestPath);
     assert(p.string<CharT>() == S);
   }
+  // basic_string<Char, Traits, Alloc>
+  {
+    const std::basic_string_view<CharT> S(TestPath);
+    path p; PathReserve(p, S.length() + 1);
+    {
+      // string provides a contigious iterator. No allocation needed.
+      DisableAllocationGuard g;
+      path& pref = (p = S);
+      assert(&pref == &p);
+    }
+    assert(p.native() == Expect);
+    assert(p.string<CharT>() == TestPath);
+    assert(p.string<CharT>() == S);
+  }
+  {
+    const std::basic_string_view<CharT> S(TestPath);
+    path p; PathReserve(p, S.length() + 1);
+    {
+      DisableAllocationGuard g;
+      path& pref = p.assign(S);
+      assert(&pref == &p);
+    }
+    assert(p.native() == Expect);
+    assert(p.string<CharT>() == TestPath);
+    assert(p.string<CharT>() == S);
+  }
   //////////////////////////////////////////////////////////////////////////////
   // Char* pointers
   {
@@ -143,6 +170,49 @@ void RunTestCase(MultiStringType const& MS) {
   }
 }
 
+template <class It, class = decltype(fs::path{}.assign(std::declval<It>()))>
+constexpr bool has_assign(int) { return true; }
+template <class It>
+constexpr bool has_assign(long) { return false; }
+template <class It>
+constexpr bool has_assign() { return has_assign<It>(0); }
+
+void test_sfinae() {
+  using namespace fs;
+  {
+    using It = const char* const;
+    static_assert(std::is_assignable<path, It>::value, "");
+    static_assert(has_assign<It>(), "");
+  }
+  {
+    using It = input_iterator<const char*>;
+    static_assert(std::is_assignable<path, It>::value, "");
+    static_assert(has_assign<It>(), "");
+  }
+  {
+    struct Traits {
+      using iterator_category = std::input_iterator_tag;
+      using value_type = const char;
+      using pointer = const char*;
+      using reference = const char&;
+      using difference_type = std::ptrdiff_t;
+    };
+    using It = input_iterator<const char*, Traits>;
+    static_assert(std::is_assignable<path, It>::value, "");
+    static_assert(has_assign<It>(), "");
+  }
+  {
+    using It = output_iterator<const char*>;
+    static_assert(!std::is_assignable<path, It>::value, "");
+    static_assert(!has_assign<It>(), "");
+
+  }
+  {
+    static_assert(!std::is_assignable<path, int*>::value, "");
+    static_assert(!has_assign<int*>(), "");
+  }
+}
+
 int main() {
   for (auto const& MS : PathList) {
     RunTestCase<char>(MS);
@@ -150,4 +220,5 @@ int main() {
     RunTestCase<char16_t>(MS);
     RunTestCase<char32_t>(MS);
   }
+  test_sfinae();
 }