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

[A. Jiang via libcxx-commits]

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@@ -81,25 +83,48 @@ static_assert(test(std::ranges::ssize, a));
 // 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::istream<int>, stream));
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frederick-vs-ja wrote:

There is a real issue with generic-no-localization. We don't define, but merely forward-declare stream types, when `_LIBCPP_HAS_LOCALIZATION` is not defined. However, we unconditionally provide `istream_view`.

https://github.com/llvm/llvm-project/pull/149557