[libcxx-commits] [libcxx] [libc++] Add missing CPO tests for range adaptors (PR #149557)

[A. Jiang via libcxx-commits]

https://github.com/frederick-vs-ja updated https://github.com/llvm/llvm-project/pull/149557

>From 8ab12116cbe5544ed14e1b2ac8971649b13190ce Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Fri, 18 Jul 2025 14:33:18 -0400
Subject: [PATCH 1/2] [libc++] Add missing CPO tests for range adaptors

---
 .../cpo.compile.pass.cpp                      | 40 ++++++++++++++-----
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp b/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp
index 3f4317a724add..9889ff2e59607 100644
--- a/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp
+++ b/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp
@@ -15,6 +15,7 @@
 #include <concepts>
 #include <iterator>
 #include <ranges>
+#include <sstream>
 #include <type_traits>
 #include <utility>
 
@@ -26,7 +27,7 @@ constexpr bool test(CPO& o, Args&&...) {
   static_assert(std::is_trivially_copyable_v<CPO>);
   static_assert(std::is_trivially_default_constructible_v<CPO>);
 
-  auto p = o;
+  auto p  = o;
   using T = decltype(p);
 
   // The type of a customization point object, ignoring cv-qualifiers, shall model semiregular.
@@ -43,7 +44,8 @@ constexpr bool test(CPO& o, Args&&...) {
 
 int a[10];
 int arrays[10][10];
-//std::pair<int, int> pairs[10];
+std::pair<int, int> pairs[10];
+std::istringstream stream;
 
 // [concept.swappable]
 static_assert(test(std::ranges::swap, a, a));
@@ -77,23 +79,41 @@ static_assert(test(std::ranges::ssize, a));
 
 // [range.factories]
 // views::empty<T> is not a CPO
-static_assert(test(std::views::iota, 1));
 static_assert(test(std::views::iota, 1, 10));
-//static_assert(test(std::views::istream<int>, 1);
+static_assert(test(std::views::iota, 1));
+static_assert(test(std::views::istream<int>, stream));
+static_assert(test(std::views::repeat, 1));
 static_assert(test(std::views::single, 4));
 
 // [range.adaptors]
+// static_assert(test(std::views::adjacent_transform<2>, [](int x, int y) { return x + y; }, a));
+// static_assert(test(std::views::adjacent<2>, a));
 static_assert(test(std::views::all, a));
+// static_assert(test(std::views::as_const, a));
+static_assert(test(std::views::as_rvalue, a));
+// static_assert(test(std::views::cache_latest, a));
+// static_assert(test(std::views::cartesian_product, a, a, a));
+static_assert(test(std::views::chunk_by, a, [](int x, int y) { return x < y; }));
+// static_assert(test(std::views::chunk, a, 1));
 static_assert(test(std::views::common, a));
+// static_assert(test(std::views::concat, a, a));
 static_assert(test(std::views::counted, a, 10));
+static_assert(test(std::views::drop_while, a, [](int x) { return x < 10; }));
 static_assert(test(std::views::drop, a, 10));
-//static_assert(test(std::views::drop_while, a, [](int x){ return x < 10; }));
-//static_assert(test(std::views::elements<0>, pairs));
-static_assert(test(std::views::filter, a, [](int x){ return x < 10; }));
+static_assert(test(std::views::elements<0>, pairs));
+// static_assert(test(std::views::enumerate, a));
+static_assert(test(std::views::filter, a, [](int x) { return x < 10; }));
+static_assert(test(std::views::join_with, 1));
 static_assert(test(std::views::join, arrays));
-//static_assert(test(std::views::split, a, 4));
+static_assert(test(std::views::keys, pairs));
 static_assert(test(std::views::lazy_split, a, 4));
 static_assert(test(std::views::reverse, a));
+static_assert(test(std::views::split, a, 4));
+// static_assert(test(std::views::stride, a, 1));
+static_assert(test(std::views::take_while, a, [](int x) { return x < 10; }));
 static_assert(test(std::views::take, a, 10));
-//static_assert(test(std::views::take_while, a, [](int x){ return x < 10; }));
-static_assert(test(std::views::transform, a, [](int x){ return x + 1; }));
+// static_assert(test(std::views::to_input, a));
+static_assert(test(std::views::transform, a, [](int x) { return x + 1; }));
+static_assert(test(std::views::values, pairs));
+// static_assert(test(std::views::zip_transform, [](int x, int y) { return x + y; }, a, a));
+static_assert(test(std::views::zip, a, a));

>From 21ecd590ab4151cd242327afa066a0dfd99faca2 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Mon, 21 Jul 2025 12:09:28 -0400
Subject: [PATCH 2/2] Guard checks for each standard

---
 .../cpo.compile.pass.cpp                      | 34 ++++++++++++-------
 1 file changed, 21 insertions(+), 13 deletions(-)

diff --git a/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp b/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp
index 9889ff2e59607..ed937dfba1ebf 100644
--- a/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp
+++ b/libcxx/test/std/library/description/conventions/customization.point.object/cpo.compile.pass.cpp
@@ -19,6 +19,8 @@
 #include <type_traits>
 #include <utility>
 
+#include "test_macros.h"
+
 // Test for basic properties of C++20 16.3.3.3.6 [customization.point.object].
 template <class CPO, class... Args>
 constexpr bool test(CPO& o, Args&&...) {
@@ -86,34 +88,40 @@ static_assert(test(std::views::repeat, 1));
 static_assert(test(std::views::single, 4));
 
 // [range.adaptors]
-// static_assert(test(std::views::adjacent_transform<2>, [](int x, int y) { return x + y; }, a));
-// static_assert(test(std::views::adjacent<2>, a));
 static_assert(test(std::views::all, a));
-// static_assert(test(std::views::as_const, a));
-static_assert(test(std::views::as_rvalue, a));
-// static_assert(test(std::views::cache_latest, a));
-// static_assert(test(std::views::cartesian_product, a, a, a));
-static_assert(test(std::views::chunk_by, a, [](int x, int y) { return x < y; }));
-// static_assert(test(std::views::chunk, a, 1));
 static_assert(test(std::views::common, a));
-// static_assert(test(std::views::concat, a, a));
 static_assert(test(std::views::counted, a, 10));
 static_assert(test(std::views::drop_while, a, [](int x) { return x < 10; }));
 static_assert(test(std::views::drop, a, 10));
 static_assert(test(std::views::elements<0>, pairs));
-// static_assert(test(std::views::enumerate, a));
 static_assert(test(std::views::filter, a, [](int x) { return x < 10; }));
-static_assert(test(std::views::join_with, 1));
 static_assert(test(std::views::join, arrays));
 static_assert(test(std::views::keys, pairs));
 static_assert(test(std::views::lazy_split, a, 4));
 static_assert(test(std::views::reverse, a));
 static_assert(test(std::views::split, a, 4));
-// static_assert(test(std::views::stride, a, 1));
 static_assert(test(std::views::take_while, a, [](int x) { return x < 10; }));
 static_assert(test(std::views::take, a, 10));
-// static_assert(test(std::views::to_input, a));
 static_assert(test(std::views::transform, a, [](int x) { return x + 1; }));
 static_assert(test(std::views::values, pairs));
+
+#if TEST_STD_VER >= 23
+// static_assert(test(std::views::adjacent_transform<2>, [](int x, int y) { return x + y; }, a));
+// static_assert(test(std::views::adjacent<2>, a));
+// static_assert(test(std::views::as_const, a));
+static_assert(test(std::views::as_rvalue, a));
+// static_assert(test(std::views::cartesian_product, a, a, a));
+static_assert(test(std::views::chunk_by, a, [](int x, int y) { return x < y; }));
+// static_assert(test(std::views::chunk, a, 1));
+// static_assert(test(std::views::enumerate, a));
+static_assert(test(std::views::join_with, 1));
+// static_assert(test(std::views::stride, a, 1));
 // static_assert(test(std::views::zip_transform, [](int x, int y) { return x + y; }, a, a));
 static_assert(test(std::views::zip, a, a));
+#endif
+
+#if TEST_STD_VER >= 26
+// static_assert(test(std::views::cache_latest, a));
+// static_assert(test(std::views::concat, a, a));
+// static_assert(test(std::views::to_input, a));
+#endif