[libcxx-commits] [libcxx] [libc++][test] Augment `test_alloc` in `deallocate_size.pass.cpp` (PR #113638)

[A. Jiang via libcxx-commits]

https://github.com/frederick-vs-ja created https://github.com/llvm/llvm-project/pull/113638

Making it meet the requirements for allocator since C++11. Fixes #113609.

This PR doesn't make it meet the C++03 allocator requirements, because that would make the type too verbose and libc++ has backported many C++11 features to the C++03 mode.

Drive-by: Removes the `TEST_CONSTEXPR_CXX14` on `allocate`/`dealocate` which is never in effect (and causes IFNDR-ness before C++23), since these functions modify the namespace-scoped variable `allocated_`.

>From e0f270b21ab6baccac47fba0396b8f7ff0059b9d Mon Sep 17 00:00:00 2001
From: "A. Jiang" <de34 at live.cn>
Date: Fri, 25 Oct 2024 10:55:13 +0800
Subject: [PATCH] [libc++][test] Augment `test_alloc` in
 `deallocate_size.pass.cpp`

Making it meet the requirements for allocator since C++11.

This PR doesn't make it meet the C++03 allocator requirements, because that would make the type too verbose and libc++ has backported many C++11 features to the C++03 mode.

Drive-by: Removes the `TEST_CONSTEXPR_CXX14` on `allocate`/`dealocate` which is never in effect (and causes IFNDR-ness before C++23), since these functions modify the namespace-scoped variable `allocated_`.
---
 .../string.capacity/deallocate_size.pass.cpp  | 21 +++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/libcxx/test/std/strings/basic.string/string.capacity/deallocate_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.capacity/deallocate_size.pass.cpp
index 1203b2f3ec18f9..00f9e2b8467837 100644
--- a/libcxx/test/std/strings/basic.string/string.capacity/deallocate_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.capacity/deallocate_size.pass.cpp
@@ -34,15 +34,32 @@ struct test_alloc {
     typedef test_alloc<U, Sz> other;
   };
 
-  TEST_CONSTEXPR_CXX14 pointer allocate(size_type n, const void* = nullptr) {
+  TEST_CONSTEXPR test_alloc() TEST_NOEXCEPT {}
+
+  template <class U>
+  TEST_CONSTEXPR test_alloc(const test_alloc<U, Sz>&) TEST_NOEXCEPT {}
+
+  pointer allocate(size_type n, const void* = nullptr) {
     allocated_ += n;
     return std::allocator<value_type>().allocate(n);
   }
 
-  TEST_CONSTEXPR_CXX14 void deallocate(pointer p, size_type s) {
+  void deallocate(pointer p, size_type s) {
     allocated_ -= s;
     std::allocator<value_type>().deallocate(p, s);
   }
+
+  template <class U>
+  friend TEST_CONSTEXPR bool operator==(const test_alloc&, const test_alloc<U, Sz>&) TEST_NOEXCEPT {
+    return true;
+  }
+
+#if TEST_STD_VER < 20
+  template <class U>
+  friend TEST_CONSTEXPR bool operator!=(const test_alloc&, const test_alloc<U, Sz>&) TEST_NOEXCEPT {
+    return false;
+  }
+#endif
 };
 
 template <class Sz>