[libcxx-commits] [libcxx] [libc++][string] P3044R2: sub-`string_view` from `string` (PR #147095)

[Louis Dionne via libcxx-commits]

================
@@ -46,79 +56,101 @@ void test1(std::basic_string_view<CharT> sv, std::size_t n, size_t pos) {
     assert(sv[pos + i] == sv1[i]);
 }
 
-template <typename CharT>
-void test(const CharT* s) {
-  typedef std::basic_string_view<CharT> string_view_t;
+template <typename CharT, typename Test<CharT>::Sub TestSub>
+void testCases(const CharT* s) {
+  std::basic_string_view<CharT> sv(s);
 
-  string_view_t sv1(s);
+  testDetail<CharT, TestSub>(sv, 0, 0);
+  testDetail<CharT, TestSub>(sv, 1, 0);
+  testDetail<CharT, TestSub>(sv, 20, 0);
+  testDetail<CharT, TestSub>(sv, sv.size(), 0);
 
-  test1(sv1, 0, 0);
-  test1(sv1, 1, 0);
-  test1(sv1, 20, 0);
-  test1(sv1, sv1.size(), 0);
+  testDetail<CharT, TestSub>(sv, 100, 3);
 
-  test1(sv1, 0, 3);
-  test1(sv1, 2, 3);
-  test1(sv1, 100, 3);
+  testDetail<CharT, TestSub>(sv, 0, std::basic_string_view<CharT>::npos);
+  testDetail<CharT, TestSub>(sv, 2, std::basic_string_view<CharT>::npos);
+  testDetail<CharT, TestSub>(sv, sv.size(), std::basic_string_view<CharT>::npos);
 
-  test1(sv1, 0, string_view_t::npos);
-  test1(sv1, 2, string_view_t::npos);
-  test1(sv1, sv1.size(), string_view_t::npos);
+  testDetail<CharT, TestSub>(sv, sv.size() + 1, 0);
+  testDetail<CharT, TestSub>(sv, sv.size() + 1, 1);
+  testDetail<CharT, TestSub>(sv, sv.size() + 1, std::basic_string_view<CharT>::npos);
+}
 
-  test1(sv1, sv1.size() + 1, 0);
-  test1(sv1, sv1.size() + 1, 1);
-  test1(sv1, sv1.size() + 1, string_view_t::npos);
+template <typename CharT>
+void testSubs(const CharT* s) {
+  testCases<CharT, &std::basic_string_view<CharT>::substr>(s);
+#if TEST_STD_VER >= 26
+  testCases<CharT, &std::basic_string_view<CharT>::subview>(s);
+#endif // TEST_STD_VER >= 26
----------------
ldionne wrote:

```suggestion
#endif
```

Not needed for such a small block

https://github.com/llvm/llvm-project/pull/147095