xref: /llvm-project-15.0.7/libcxx/test/std/strings/basic.string/string.starts_with/starts_with.ptr.pass.cpp (revision 425620cc)

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17

// <string>

// constexpr bool starts_with(const CharT *x) const;

#include <string>
#include <cassert>

#include "test_macros.h"

constexpr bool test() {
  {
    typedef std::string S;
    const char *s = "abcde";
    S  s0 {};
    S  s1 { s, 1 };
    S  s2 { s, 2 };
//     S  s3 { s, 3 };
//     S  s4 { s, 4 };
//     S  s5 { s, 5 };
    S  sNot {"def", 3 };

    LIBCPP_ASSERT_NOEXCEPT(s0.starts_with(""));

    assert ( s0.starts_with(""));
    assert (!s0.starts_with("a"));

    assert ( s1.starts_with(""));
    assert ( s1.starts_with("a"));
    assert (!s1.starts_with("ab"));
    assert (!s1.starts_with("abc"));
    assert (!s1.starts_with("abcd"));
    assert (!s1.starts_with("abcde"));
    assert (!s1.starts_with("def"));

    assert ( s2.starts_with(""));
    assert ( s2.starts_with("a"));
    assert ( s2.starts_with("ab"));
    assert (!s2.starts_with("abc"));
    assert (!s2.starts_with("abcd"));
    assert (!s2.starts_with("abcde"));
    assert (!s2.starts_with("def"));

    assert ( sNot.starts_with(""));
    assert (!sNot.starts_with("a"));
    assert (!sNot.starts_with("ab"));
    assert (!sNot.starts_with("abc"));
    assert (!sNot.starts_with("abcd"));
    assert (!sNot.starts_with("abcde"));
    assert ( sNot.starts_with("def"));
  }

  return true;
}

int main(int, char**)
{
  test();
  static_assert(test());

  return 0;
}