🐛 Fix ct_capacity_v for const types

elbeno · elbeno · commit 70819dc240ae · 2024-02-16T11:02:30.000-07:00
diff --git a/include/stdx/iterator.hpp b/include/stdx/iterator.hpp
@@ -20,6 +20,8 @@ constexpr auto ct_capacity_v = detail::ct_capacity_fail<T>{};
 template <typename T, std::size_t N>
 constexpr auto ct_capacity_v<std::array<T, N>> = N;
 
+template <typename T> constexpr auto ct_capacity_v<T const> = ct_capacity_v<T>;
+
 template <typename T> constexpr auto ct_capacity(T &&) -> std::size_t {
     return ct_capacity_v<remove_cvref_t<T>>;
 }
diff --git a/test/iterator.cpp b/test/iterator.cpp
@@ -57,3 +57,13 @@ TEST_CASE("compile-time capacity (stdx::cx_vector)", "[iterator]") {
     stdx::cx_vector<int, 4> v{};
     static_assert(stdx::ct_capacity(v) == 4u);
 }
+
+TEST_CASE("compile-time capacity variable template", "[iterator]") {
+    std::array a{1, 2, 3, 4};
+    static_assert(stdx::ct_capacity_v<decltype(a)> == 4u);
+}
+
+TEST_CASE("compile-time capacity variable template (const)", "[iterator]") {
+    std::array const a{1, 2, 3, 4};
+    static_assert(stdx::ct_capacity_v<decltype(a)> == 4u);
+}

Original file line number	Diff line number	Diff line change
`@@ -20,6 +20,8 @@ constexpr auto ct_capacity_v = detail::ct_capacity_fail<T>{};`
`20`	`20`	`template <typename T, std::size_t N>`
`21`	`21`	`constexpr auto ct_capacity_v<std::array<T, N>> = N;`
`22`	`22`
	`23`	`+template <typename T> constexpr auto ct_capacity_v<T const> = ct_capacity_v<T>;`
	`24`	`+`
`23`	`25`	`template <typename T> constexpr auto ct_capacity(T &&) -> std::size_t {`
`24`	`26`	`return ct_capacity_v<remove_cvref_t<T>>;`
`25`	`27`	`}`