1 files changed, 59 insertions, 0 deletions
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
new file mode 100644
index 00000000000..bcfb16e050e
--- /dev/null
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <locale>
+
+// wbuffer_convert<Codecvt, Elem, Tr>
+
+// int_type pbackfail(int_type c = traits::eof());
+
+// This test is not entirely portable
+
+#include <locale>
+#include <codecvt>
+#include <fstream>
+#include <cassert>
+
+struct test_buf
+    : public std::wbuffer_convert<std::codecvt_utf8<wchar_t> >
+{
+    typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > base;
+    typedef base::char_type   char_type;
+    typedef base::int_type    int_type;
+    typedef base::traits_type traits_type;
+
+    explicit test_buf(std::streambuf* sb) : base(sb) {}
+
+    char_type* eback() const {return base::eback();}
+    char_type* gptr()  const {return base::gptr();}
+    char_type* egptr() const {return base::egptr();}
+    void gbump(int n) {base::gbump(n);}
+
+    virtual int_type pbackfail(int_type c = traits_type::eof()) {return base::pbackfail(c);}
+};
+
+int main()
+{
+    {
+        std::ifstream bs("underflow.dat");
+        test_buf f(bs.rdbuf());
+        assert(f.sbumpc() == L'1');
+        assert(f.sgetc() == L'2');
+        assert(f.pbackfail(L'a') == test_buf::traits_type::eof());
+    }
+    {
+        std::fstream bs("underflow.dat");
+        test_buf f(bs.rdbuf());
+        assert(f.sbumpc() == L'1');
+        assert(f.sgetc() == L'2');
+        assert(f.pbackfail(L'a') == test_buf::traits_type::eof());
+        assert(f.sbumpc() == L'2');
+        assert(f.sgetc() == L'3');
+    }
+}