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 
9 // UNSUPPORTED: !stdlib=libc++ && (c++03 || c++11 || c++14)
10 
11 // <string_view>
12 
13 // constexpr int compare(size_type pos1, size_type n1, const charT* s) const;
14 
15 #include <string_view>
16 #include <cassert>
17 #include <stdexcept>
18 
19 #include "test_macros.h"
20 #include "constexpr_char_traits.h"
21 
sign(int x)22 int sign ( int x ) { return x > 0 ? 1 : ( x < 0 ? -1 : 0 ); }
23 
24 template<typename CharT>
test1(std::basic_string_view<CharT> sv1,size_t pos1,size_t n1,const CharT * s,int expected)25 void test1 ( std::basic_string_view<CharT> sv1,
26              size_t pos1, size_t n1, const CharT *s, int expected ) {
27 #ifdef TEST_HAS_NO_EXCEPTIONS
28     if (pos1 <= sv1.size())
29         assert(sign(sv1.compare(pos1, n1, s)) == sign(expected));
30 #else
31     try {
32         assert(sign(sv1.compare(pos1, n1, s)) == sign(expected));
33         assert(pos1 <= sv1.size());
34     }
35     catch (const std::out_of_range&) {
36         assert(pos1 > sv1.size());
37     }
38 #endif
39 }
40 
41 template<typename CharT>
42 void
test(const CharT * s1,size_t pos1,size_t n1,const CharT * s2,int expected)43 test( const CharT *s1, size_t pos1, size_t n1, const CharT *s2, int expected)
44 {
45     typedef std::basic_string_view<CharT> string_view_t;
46     string_view_t sv1 ( s1 );
47     test1 ( sv1, pos1, n1, s2, expected );
48 }
49 
test0()50 void test0()
51 {
52     test("", 0, 0, "", 0);
53     test("", 0, 0, "abcde", -5);
54     test("", 0, 0, "abcdefghij", -10);
55     test("", 0, 0, "abcdefghijklmnopqrst", -20);
56     test("", 0, 1, "", 0);
57     test("", 0, 1, "abcde", -5);
58     test("", 0, 1, "abcdefghij", -10);
59     test("", 0, 1, "abcdefghijklmnopqrst", -20);
60     test("", 1, 0, "", 0);
61     test("", 1, 0, "abcde", 0);
62     test("", 1, 0, "abcdefghij", 0);
63     test("", 1, 0, "abcdefghijklmnopqrst", 0);
64     test("abcde", 0, 0, "", 0);
65     test("abcde", 0, 0, "abcde", -5);
66     test("abcde", 0, 0, "abcdefghij", -10);
67     test("abcde", 0, 0, "abcdefghijklmnopqrst", -20);
68     test("abcde", 0, 1, "", 1);
69     test("abcde", 0, 1, "abcde", -4);
70     test("abcde", 0, 1, "abcdefghij", -9);
71     test("abcde", 0, 1, "abcdefghijklmnopqrst", -19);
72     test("abcde", 0, 2, "", 2);
73     test("abcde", 0, 2, "abcde", -3);
74     test("abcde", 0, 2, "abcdefghij", -8);
75     test("abcde", 0, 2, "abcdefghijklmnopqrst", -18);
76     test("abcde", 0, 4, "", 4);
77     test("abcde", 0, 4, "abcde", -1);
78     test("abcde", 0, 4, "abcdefghij", -6);
79     test("abcde", 0, 4, "abcdefghijklmnopqrst", -16);
80     test("abcde", 0, 5, "", 5);
81     test("abcde", 0, 5, "abcde", 0);
82     test("abcde", 0, 5, "abcdefghij", -5);
83     test("abcde", 0, 5, "abcdefghijklmnopqrst", -15);
84     test("abcde", 0, 6, "", 5);
85     test("abcde", 0, 6, "abcde", 0);
86     test("abcde", 0, 6, "abcdefghij", -5);
87     test("abcde", 0, 6, "abcdefghijklmnopqrst", -15);
88     test("abcde", 1, 0, "", 0);
89     test("abcde", 1, 0, "abcde", -5);
90     test("abcde", 1, 0, "abcdefghij", -10);
91     test("abcde", 1, 0, "abcdefghijklmnopqrst", -20);
92     test("abcde", 1, 1, "", 1);
93     test("abcde", 1, 1, "abcde", 1);
94     test("abcde", 1, 1, "abcdefghij", 1);
95     test("abcde", 1, 1, "abcdefghijklmnopqrst", 1);
96     test("abcde", 1, 2, "", 2);
97     test("abcde", 1, 2, "abcde", 1);
98     test("abcde", 1, 2, "abcdefghij", 1);
99     test("abcde", 1, 2, "abcdefghijklmnopqrst", 1);
100     test("abcde", 1, 3, "", 3);
101     test("abcde", 1, 3, "abcde", 1);
102     test("abcde", 1, 3, "abcdefghij", 1);
103     test("abcde", 1, 3, "abcdefghijklmnopqrst", 1);
104     test("abcde", 1, 4, "", 4);
105     test("abcde", 1, 4, "abcde", 1);
106     test("abcde", 1, 4, "abcdefghij", 1);
107     test("abcde", 1, 4, "abcdefghijklmnopqrst", 1);
108     test("abcde", 1, 5, "", 4);
109     test("abcde", 1, 5, "abcde", 1);
110     test("abcde", 1, 5, "abcdefghij", 1);
111     test("abcde", 1, 5, "abcdefghijklmnopqrst", 1);
112     test("abcde", 2, 0, "", 0);
113     test("abcde", 2, 0, "abcde", -5);
114     test("abcde", 2, 0, "abcdefghij", -10);
115     test("abcde", 2, 0, "abcdefghijklmnopqrst", -20);
116     test("abcde", 2, 1, "", 1);
117     test("abcde", 2, 1, "abcde", 2);
118     test("abcde", 2, 1, "abcdefghij", 2);
119     test("abcde", 2, 1, "abcdefghijklmnopqrst", 2);
120     test("abcde", 2, 2, "", 2);
121     test("abcde", 2, 2, "abcde", 2);
122     test("abcde", 2, 2, "abcdefghij", 2);
123     test("abcde", 2, 2, "abcdefghijklmnopqrst", 2);
124     test("abcde", 2, 3, "", 3);
125     test("abcde", 2, 3, "abcde", 2);
126     test("abcde", 2, 3, "abcdefghij", 2);
127     test("abcde", 2, 3, "abcdefghijklmnopqrst", 2);
128     test("abcde", 2, 4, "", 3);
129     test("abcde", 2, 4, "abcde", 2);
130     test("abcde", 2, 4, "abcdefghij", 2);
131     test("abcde", 2, 4, "abcdefghijklmnopqrst", 2);
132     test("abcde", 4, 0, "", 0);
133     test("abcde", 4, 0, "abcde", -5);
134     test("abcde", 4, 0, "abcdefghij", -10);
135     test("abcde", 4, 0, "abcdefghijklmnopqrst", -20);
136     test("abcde", 4, 1, "", 1);
137     test("abcde", 4, 1, "abcde", 4);
138     test("abcde", 4, 1, "abcdefghij", 4);
139     test("abcde", 4, 1, "abcdefghijklmnopqrst", 4);
140     test("abcde", 4, 2, "", 1);
141     test("abcde", 4, 2, "abcde", 4);
142     test("abcde", 4, 2, "abcdefghij", 4);
143     test("abcde", 4, 2, "abcdefghijklmnopqrst", 4);
144     test("abcde", 5, 0, "", 0);
145     test("abcde", 5, 0, "abcde", -5);
146     test("abcde", 5, 0, "abcdefghij", -10);
147     test("abcde", 5, 0, "abcdefghijklmnopqrst", -20);
148     test("abcde", 5, 1, "", 0);
149     test("abcde", 5, 1, "abcde", -5);
150     test("abcde", 5, 1, "abcdefghij", -10);
151     test("abcde", 5, 1, "abcdefghijklmnopqrst", -20);
152 }
153 
test1()154 void test1()
155 {
156     test("abcde", 6, 0, "", 0);
157     test("abcde", 6, 0, "abcde", 0);
158     test("abcde", 6, 0, "abcdefghij", 0);
159     test("abcde", 6, 0, "abcdefghijklmnopqrst", 0);
160     test("abcdefghij", 0, 0, "", 0);
161     test("abcdefghij", 0, 0, "abcde", -5);
162     test("abcdefghij", 0, 0, "abcdefghij", -10);
163     test("abcdefghij", 0, 0, "abcdefghijklmnopqrst", -20);
164     test("abcdefghij", 0, 1, "", 1);
165     test("abcdefghij", 0, 1, "abcde", -4);
166     test("abcdefghij", 0, 1, "abcdefghij", -9);
167     test("abcdefghij", 0, 1, "abcdefghijklmnopqrst", -19);
168     test("abcdefghij", 0, 5, "", 5);
169     test("abcdefghij", 0, 5, "abcde", 0);
170     test("abcdefghij", 0, 5, "abcdefghij", -5);
171     test("abcdefghij", 0, 5, "abcdefghijklmnopqrst", -15);
172     test("abcdefghij", 0, 9, "", 9);
173     test("abcdefghij", 0, 9, "abcde", 4);
174     test("abcdefghij", 0, 9, "abcdefghij", -1);
175     test("abcdefghij", 0, 9, "abcdefghijklmnopqrst", -11);
176     test("abcdefghij", 0, 10, "", 10);
177     test("abcdefghij", 0, 10, "abcde", 5);
178     test("abcdefghij", 0, 10, "abcdefghij", 0);
179     test("abcdefghij", 0, 10, "abcdefghijklmnopqrst", -10);
180     test("abcdefghij", 0, 11, "", 10);
181     test("abcdefghij", 0, 11, "abcde", 5);
182     test("abcdefghij", 0, 11, "abcdefghij", 0);
183     test("abcdefghij", 0, 11, "abcdefghijklmnopqrst", -10);
184     test("abcdefghij", 1, 0, "", 0);
185     test("abcdefghij", 1, 0, "abcde", -5);
186     test("abcdefghij", 1, 0, "abcdefghij", -10);
187     test("abcdefghij", 1, 0, "abcdefghijklmnopqrst", -20);
188     test("abcdefghij", 1, 1, "", 1);
189     test("abcdefghij", 1, 1, "abcde", 1);
190     test("abcdefghij", 1, 1, "abcdefghij", 1);
191     test("abcdefghij", 1, 1, "abcdefghijklmnopqrst", 1);
192     test("abcdefghij", 1, 4, "", 4);
193     test("abcdefghij", 1, 4, "abcde", 1);
194     test("abcdefghij", 1, 4, "abcdefghij", 1);
195     test("abcdefghij", 1, 4, "abcdefghijklmnopqrst", 1);
196     test("abcdefghij", 1, 8, "", 8);
197     test("abcdefghij", 1, 8, "abcde", 1);
198     test("abcdefghij", 1, 8, "abcdefghij", 1);
199     test("abcdefghij", 1, 8, "abcdefghijklmnopqrst", 1);
200     test("abcdefghij", 1, 9, "", 9);
201     test("abcdefghij", 1, 9, "abcde", 1);
202     test("abcdefghij", 1, 9, "abcdefghij", 1);
203     test("abcdefghij", 1, 9, "abcdefghijklmnopqrst", 1);
204     test("abcdefghij", 1, 10, "", 9);
205     test("abcdefghij", 1, 10, "abcde", 1);
206     test("abcdefghij", 1, 10, "abcdefghij", 1);
207     test("abcdefghij", 1, 10, "abcdefghijklmnopqrst", 1);
208     test("abcdefghij", 5, 0, "", 0);
209     test("abcdefghij", 5, 0, "abcde", -5);
210     test("abcdefghij", 5, 0, "abcdefghij", -10);
211     test("abcdefghij", 5, 0, "abcdefghijklmnopqrst", -20);
212     test("abcdefghij", 5, 1, "", 1);
213     test("abcdefghij", 5, 1, "abcde", 5);
214     test("abcdefghij", 5, 1, "abcdefghij", 5);
215     test("abcdefghij", 5, 1, "abcdefghijklmnopqrst", 5);
216     test("abcdefghij", 5, 2, "", 2);
217     test("abcdefghij", 5, 2, "abcde", 5);
218     test("abcdefghij", 5, 2, "abcdefghij", 5);
219     test("abcdefghij", 5, 2, "abcdefghijklmnopqrst", 5);
220     test("abcdefghij", 5, 4, "", 4);
221     test("abcdefghij", 5, 4, "abcde", 5);
222     test("abcdefghij", 5, 4, "abcdefghij", 5);
223     test("abcdefghij", 5, 4, "abcdefghijklmnopqrst", 5);
224     test("abcdefghij", 5, 5, "", 5);
225     test("abcdefghij", 5, 5, "abcde", 5);
226     test("abcdefghij", 5, 5, "abcdefghij", 5);
227     test("abcdefghij", 5, 5, "abcdefghijklmnopqrst", 5);
228     test("abcdefghij", 5, 6, "", 5);
229     test("abcdefghij", 5, 6, "abcde", 5);
230     test("abcdefghij", 5, 6, "abcdefghij", 5);
231     test("abcdefghij", 5, 6, "abcdefghijklmnopqrst", 5);
232     test("abcdefghij", 9, 0, "", 0);
233     test("abcdefghij", 9, 0, "abcde", -5);
234     test("abcdefghij", 9, 0, "abcdefghij", -10);
235     test("abcdefghij", 9, 0, "abcdefghijklmnopqrst", -20);
236     test("abcdefghij", 9, 1, "", 1);
237     test("abcdefghij", 9, 1, "abcde", 9);
238     test("abcdefghij", 9, 1, "abcdefghij", 9);
239     test("abcdefghij", 9, 1, "abcdefghijklmnopqrst", 9);
240     test("abcdefghij", 9, 2, "", 1);
241     test("abcdefghij", 9, 2, "abcde", 9);
242     test("abcdefghij", 9, 2, "abcdefghij", 9);
243     test("abcdefghij", 9, 2, "abcdefghijklmnopqrst", 9);
244     test("abcdefghij", 10, 0, "", 0);
245     test("abcdefghij", 10, 0, "abcde", -5);
246     test("abcdefghij", 10, 0, "abcdefghij", -10);
247     test("abcdefghij", 10, 0, "abcdefghijklmnopqrst", -20);
248     test("abcdefghij", 10, 1, "", 0);
249     test("abcdefghij", 10, 1, "abcde", -5);
250     test("abcdefghij", 10, 1, "abcdefghij", -10);
251     test("abcdefghij", 10, 1, "abcdefghijklmnopqrst", -20);
252     test("abcdefghij", 11, 0, "", 0);
253     test("abcdefghij", 11, 0, "abcde", 0);
254     test("abcdefghij", 11, 0, "abcdefghij", 0);
255     test("abcdefghij", 11, 0, "abcdefghijklmnopqrst", 0);
256 }
257 
test2()258 void test2()
259 {
260     test("abcdefghijklmnopqrst", 0, 0, "", 0);
261     test("abcdefghijklmnopqrst", 0, 0, "abcde", -5);
262     test("abcdefghijklmnopqrst", 0, 0, "abcdefghij", -10);
263     test("abcdefghijklmnopqrst", 0, 0, "abcdefghijklmnopqrst", -20);
264     test("abcdefghijklmnopqrst", 0, 1, "", 1);
265     test("abcdefghijklmnopqrst", 0, 1, "abcde", -4);
266     test("abcdefghijklmnopqrst", 0, 1, "abcdefghij", -9);
267     test("abcdefghijklmnopqrst", 0, 1, "abcdefghijklmnopqrst", -19);
268     test("abcdefghijklmnopqrst", 0, 10, "", 10);
269     test("abcdefghijklmnopqrst", 0, 10, "abcde", 5);
270     test("abcdefghijklmnopqrst", 0, 10, "abcdefghij", 0);
271     test("abcdefghijklmnopqrst", 0, 10, "abcdefghijklmnopqrst", -10);
272     test("abcdefghijklmnopqrst", 0, 19, "", 19);
273     test("abcdefghijklmnopqrst", 0, 19, "abcde", 14);
274     test("abcdefghijklmnopqrst", 0, 19, "abcdefghij", 9);
275     test("abcdefghijklmnopqrst", 0, 19, "abcdefghijklmnopqrst", -1);
276     test("abcdefghijklmnopqrst", 0, 20, "", 20);
277     test("abcdefghijklmnopqrst", 0, 20, "abcde", 15);
278     test("abcdefghijklmnopqrst", 0, 20, "abcdefghij", 10);
279     test("abcdefghijklmnopqrst", 0, 20, "abcdefghijklmnopqrst", 0);
280     test("abcdefghijklmnopqrst", 0, 21, "", 20);
281     test("abcdefghijklmnopqrst", 0, 21, "abcde", 15);
282     test("abcdefghijklmnopqrst", 0, 21, "abcdefghij", 10);
283     test("abcdefghijklmnopqrst", 0, 21, "abcdefghijklmnopqrst", 0);
284     test("abcdefghijklmnopqrst", 1, 0, "", 0);
285     test("abcdefghijklmnopqrst", 1, 0, "abcde", -5);
286     test("abcdefghijklmnopqrst", 1, 0, "abcdefghij", -10);
287     test("abcdefghijklmnopqrst", 1, 0, "abcdefghijklmnopqrst", -20);
288     test("abcdefghijklmnopqrst", 1, 1, "", 1);
289     test("abcdefghijklmnopqrst", 1, 1, "abcde", 1);
290     test("abcdefghijklmnopqrst", 1, 1, "abcdefghij", 1);
291     test("abcdefghijklmnopqrst", 1, 1, "abcdefghijklmnopqrst", 1);
292     test("abcdefghijklmnopqrst", 1, 9, "", 9);
293     test("abcdefghijklmnopqrst", 1, 9, "abcde", 1);
294     test("abcdefghijklmnopqrst", 1, 9, "abcdefghij", 1);
295     test("abcdefghijklmnopqrst", 1, 9, "abcdefghijklmnopqrst", 1);
296     test("abcdefghijklmnopqrst", 1, 18, "", 18);
297     test("abcdefghijklmnopqrst", 1, 18, "abcde", 1);
298     test("abcdefghijklmnopqrst", 1, 18, "abcdefghij", 1);
299     test("abcdefghijklmnopqrst", 1, 18, "abcdefghijklmnopqrst", 1);
300     test("abcdefghijklmnopqrst", 1, 19, "", 19);
301     test("abcdefghijklmnopqrst", 1, 19, "abcde", 1);
302     test("abcdefghijklmnopqrst", 1, 19, "abcdefghij", 1);
303     test("abcdefghijklmnopqrst", 1, 19, "abcdefghijklmnopqrst", 1);
304     test("abcdefghijklmnopqrst", 1, 20, "", 19);
305     test("abcdefghijklmnopqrst", 1, 20, "abcde", 1);
306     test("abcdefghijklmnopqrst", 1, 20, "abcdefghij", 1);
307     test("abcdefghijklmnopqrst", 1, 20, "abcdefghijklmnopqrst", 1);
308     test("abcdefghijklmnopqrst", 10, 0, "", 0);
309     test("abcdefghijklmnopqrst", 10, 0, "abcde", -5);
310     test("abcdefghijklmnopqrst", 10, 0, "abcdefghij", -10);
311     test("abcdefghijklmnopqrst", 10, 0, "abcdefghijklmnopqrst", -20);
312     test("abcdefghijklmnopqrst", 10, 1, "", 1);
313     test("abcdefghijklmnopqrst", 10, 1, "abcde", 10);
314     test("abcdefghijklmnopqrst", 10, 1, "abcdefghij", 10);
315     test("abcdefghijklmnopqrst", 10, 1, "abcdefghijklmnopqrst", 10);
316     test("abcdefghijklmnopqrst", 10, 5, "", 5);
317     test("abcdefghijklmnopqrst", 10, 5, "abcde", 10);
318     test("abcdefghijklmnopqrst", 10, 5, "abcdefghij", 10);
319     test("abcdefghijklmnopqrst", 10, 5, "abcdefghijklmnopqrst", 10);
320     test("abcdefghijklmnopqrst", 10, 9, "", 9);
321     test("abcdefghijklmnopqrst", 10, 9, "abcde", 10);
322     test("abcdefghijklmnopqrst", 10, 9, "abcdefghij", 10);
323     test("abcdefghijklmnopqrst", 10, 9, "abcdefghijklmnopqrst", 10);
324     test("abcdefghijklmnopqrst", 10, 10, "", 10);
325     test("abcdefghijklmnopqrst", 10, 10, "abcde", 10);
326     test("abcdefghijklmnopqrst", 10, 10, "abcdefghij", 10);
327     test("abcdefghijklmnopqrst", 10, 10, "abcdefghijklmnopqrst", 10);
328     test("abcdefghijklmnopqrst", 10, 11, "", 10);
329     test("abcdefghijklmnopqrst", 10, 11, "abcde", 10);
330     test("abcdefghijklmnopqrst", 10, 11, "abcdefghij", 10);
331     test("abcdefghijklmnopqrst", 10, 11, "abcdefghijklmnopqrst", 10);
332     test("abcdefghijklmnopqrst", 19, 0, "", 0);
333     test("abcdefghijklmnopqrst", 19, 0, "abcde", -5);
334     test("abcdefghijklmnopqrst", 19, 0, "abcdefghij", -10);
335     test("abcdefghijklmnopqrst", 19, 0, "abcdefghijklmnopqrst", -20);
336     test("abcdefghijklmnopqrst", 19, 1, "", 1);
337     test("abcdefghijklmnopqrst", 19, 1, "abcde", 19);
338     test("abcdefghijklmnopqrst", 19, 1, "abcdefghij", 19);
339     test("abcdefghijklmnopqrst", 19, 1, "abcdefghijklmnopqrst", 19);
340     test("abcdefghijklmnopqrst", 19, 2, "", 1);
341     test("abcdefghijklmnopqrst", 19, 2, "abcde", 19);
342     test("abcdefghijklmnopqrst", 19, 2, "abcdefghij", 19);
343     test("abcdefghijklmnopqrst", 19, 2, "abcdefghijklmnopqrst", 19);
344     test("abcdefghijklmnopqrst", 20, 0, "", 0);
345     test("abcdefghijklmnopqrst", 20, 0, "abcde", -5);
346     test("abcdefghijklmnopqrst", 20, 0, "abcdefghij", -10);
347     test("abcdefghijklmnopqrst", 20, 0, "abcdefghijklmnopqrst", -20);
348     test("abcdefghijklmnopqrst", 20, 1, "", 0);
349     test("abcdefghijklmnopqrst", 20, 1, "abcde", -5);
350     test("abcdefghijklmnopqrst", 20, 1, "abcdefghij", -10);
351     test("abcdefghijklmnopqrst", 20, 1, "abcdefghijklmnopqrst", -20);
352     test("abcdefghijklmnopqrst", 21, 0, "", 0);
353     test("abcdefghijklmnopqrst", 21, 0, "abcde", 0);
354     test("abcdefghijklmnopqrst", 21, 0, "abcdefghij", 0);
355     test("abcdefghijklmnopqrst", 21, 0, "abcdefghijklmnopqrst", 0);
356 }
357 
358 
main(int,char **)359 int main(int, char**)
360 {
361     test0();
362     test1();
363     test2();
364 
365     {
366     test("", 0, 0, "", 0);
367     test("", 0, 0, "abcde", -5);
368     test("", 0, 0, "abcdefghij", -10);
369     test("", 0, 0, "abcdefghijklmnopqrst", -20);
370     test("abcde", 0, 2, "", 5);
371     test("abcde", 0, 6,"abcde", 0);
372     test("abcde", 0, 6, "abcdefghij", -5);
373     test("abcde", 0, 6, "abcdefghijklmnopqrst", -15);
374     test("abcdefghij", 3, 3, "", 10);
375     test("abcdefghij", 3, 3,"abcde", 5);
376     test("abcdefghij", 3, 3, "def", 0);
377     test("abcdefghij", 0, 4, "abcdefghijklmnopqrst", -10);
378     test("abcdefghijklmnopqrst", 5, 5, "", 20);
379     test("abcdefghijklmnopqrst", 0, 8, "abcde", 15);
380     test("abcdefghijklmnopqrst", 0, 12, "abcdefghij", 10);
381     test("abcdefghijklmnopqrst", 0, static_cast<size_t>(-1), "abcdefghijklmnopqrst", 0);
382     }
383 
384     {
385     test(L"", 0, 0, L"", 0);
386     test(L"", 0, 0, L"abcde", -5);
387     test(L"", 0, 0, L"abcdefghij", -10);
388     test(L"", 0, 0, L"abcdefghijklmnopqrst", -20);
389     test(L"abcde", 0, 2, L"", 5);
390     test(L"abcde", 0, 6, L"abcde", 0);
391     test(L"abcde", 0, 6, L"abcdefghij", -5);
392     test(L"abcde", 0, 6, L"abcdefghijklmnopqrst", -15);
393     test(L"abcdefghij", 3, 3, L"", 10);
394     test(L"abcdefghij", 3, 3, L"abcde", 5);
395     test(L"abcdefghij", 3, 3, L"def", 0);
396     test(L"abcdefghij", 0, 4, L"abcdefghijklmnopqrst", -10);
397     test(L"abcdefghijklmnopqrst", 5, 5, L"", 20);
398     test(L"abcdefghijklmnopqrst", 0, 8, L"abcde", 15);
399     test(L"abcdefghijklmnopqrst", 0, 12, L"abcdefghij", 10);
400     test(L"abcdefghijklmnopqrst", 0, static_cast<size_t>(-1), L"abcdefghijklmnopqrst", 0);
401     }
402 
403 #if TEST_STD_VER >= 11
404     {
405     test(U"", 0, 0, U"", 0);
406     test(U"", 0, 0, U"abcde", -5);
407     test(U"", 0, 0, U"abcdefghij", -10);
408     test(U"", 0, 0, U"abcdefghijklmnopqrst", -20);
409     test(U"abcde", 0, 2, U"", 5);
410     test(U"abcde", 0, 6, U"abcde", 0);
411     test(U"abcde", 0, 6, U"abcdefghij", -5);
412     test(U"abcde", 0, 6, U"abcdefghijklmnopqrst", -15);
413     test(U"abcdefghij", 3, 3, U"", 10);
414     test(U"abcdefghij", 3, 3, U"abcde", 5);
415     test(U"abcdefghij", 3, 3, U"def", 0);
416     test(U"abcdefghij", 0, 4, U"abcdefghijklmnopqrst", -10);
417     test(U"abcdefghijklmnopqrst", 5, 5, U"", 20);
418     test(U"abcdefghijklmnopqrst", 0, 8, U"abcde", 15);
419     test(U"abcdefghijklmnopqrst", 0, 12, U"abcdefghij", 10);
420     test(U"abcdefghijklmnopqrst", 0, static_cast<size_t>(-1), U"abcdefghijklmnopqrst", 0);
421     }
422 
423     {
424     test(u"", 0, 0, u"", 0);
425     test(u"", 0, 0, u"abcde", -5);
426     test(u"", 0, 0, u"abcdefghij", -10);
427     test(u"", 0, 0, u"abcdefghijklmnopqrst", -20);
428     test(u"abcde", 0, 2, u"", 5);
429     test(u"abcde", 0, 6, u"abcde", 0);
430     test(u"abcde", 0, 6, u"abcdefghij", -5);
431     test(u"abcde", 0, 6, u"abcdefghijklmnopqrst", -15);
432     test(u"abcdefghij", 3, 3, u"", 10);
433     test(u"abcdefghij", 3, 3, u"abcde", 5);
434     test(u"abcdefghij", 3, 3, u"def", 0);
435     test(u"abcdefghij", 0, 4, u"abcdefghijklmnopqrst", -10);
436     test(u"abcdefghijklmnopqrst", 5, 5, u"", 20);
437     test(u"abcdefghijklmnopqrst", 0, 8, u"abcde", 15);
438     test(u"abcdefghijklmnopqrst", 0, 12, u"abcdefghij", 10);
439     test(u"abcdefghijklmnopqrst", 0, static_cast<size_t>(-1), u"abcdefghijklmnopqrst", 0);
440     }
441 #endif
442 
443 #if TEST_STD_VER > 11
444     {
445     typedef std::basic_string_view<char, constexpr_char_traits<char>> SV;
446     constexpr SV  sv1;
447     constexpr SV  sv2 { "abcde", 5 };
448     static_assert ( sv1.compare(0, 0, "") == 0, "" );
449     static_assert ( sv1.compare(0, 0, "abcde") < 0, "" );
450     static_assert ( sv2.compare(0, 2, "") > 0, "" );
451     static_assert ( sv2.compare(0, 6, "abcde") == 0, "" );
452     }
453 #endif
454 
455   return 0;
456 }
457