1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 // UNSUPPORTED: c++03, c++11, c++14, c++17
9
10 // <string>
11
12 // constexpr bool starts_with(const CharT *x) const;
13
14 #include <string>
15 #include <cassert>
16
17 #include "test_macros.h"
18
test()19 constexpr bool test() {
20 {
21 typedef std::string S;
22 const char *s = "abcde";
23 S s0 {};
24 S s1 { s, 1 };
25 S s2 { s, 2 };
26 // S s3 { s, 3 };
27 // S s4 { s, 4 };
28 // S s5 { s, 5 };
29 S sNot {"def", 3 };
30
31 LIBCPP_ASSERT_NOEXCEPT(s0.starts_with(""));
32
33 assert ( s0.starts_with(""));
34 assert (!s0.starts_with("a"));
35
36 assert ( s1.starts_with(""));
37 assert ( s1.starts_with("a"));
38 assert (!s1.starts_with("ab"));
39 assert (!s1.starts_with("abc"));
40 assert (!s1.starts_with("abcd"));
41 assert (!s1.starts_with("abcde"));
42 assert (!s1.starts_with("def"));
43
44 assert ( s2.starts_with(""));
45 assert ( s2.starts_with("a"));
46 assert ( s2.starts_with("ab"));
47 assert (!s2.starts_with("abc"));
48 assert (!s2.starts_with("abcd"));
49 assert (!s2.starts_with("abcde"));
50 assert (!s2.starts_with("def"));
51
52 assert ( sNot.starts_with(""));
53 assert (!sNot.starts_with("a"));
54 assert (!sNot.starts_with("ab"));
55 assert (!sNot.starts_with("abc"));
56 assert (!sNot.starts_with("abcd"));
57 assert (!sNot.starts_with("abcde"));
58 assert ( sNot.starts_with("def"));
59 }
60
61 return true;
62 }
63
main(int,char **)64 int main(int, char**)
65 {
66 test();
67 static_assert(test());
68
69 return 0;
70 }
71