129 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// std::views::split12 13#include <ranges>14 15#include <array>16#include <cassert>17#include <concepts>18#include <string_view>19#include <utility>20 21#include "test_iterators.h"22#include "test_range.h"23 24struct SomeView : std::ranges::view_base {25 const std::string_view* v_;26 constexpr SomeView(const std::string_view& v) : v_(&v) {}27 constexpr auto begin() const { return v_->begin(); }28 constexpr auto end() const { return v_->end(); }29};30 31struct NotAView { };32 33static_assert(!std::is_invocable_v<decltype(std::views::split)>);34static_assert(!std::is_invocable_v<decltype(std::views::split), SomeView, NotAView>);35static_assert(!std::is_invocable_v<decltype(std::views::split), NotAView, SomeView>);36static_assert( std::is_invocable_v<decltype(std::views::split), SomeView, SomeView>);37 38// Regression test for #75002, views::split shouldn't be a range adaptor closure39static_assert(!CanBePiped<SomeView&, decltype(std::views::split)>);40static_assert(!CanBePiped<char (&)[10], decltype(std::views::split)>);41static_assert(!CanBePiped<char (&&)[10], decltype(std::views::split)>);42static_assert(!CanBePiped<NotAView, decltype(std::views::split)>);43 44static_assert(CanBePiped<SomeView&, decltype(std::views::split('x'))>);45static_assert(CanBePiped<char (&)[10], decltype(std::views::split('x'))>);46static_assert(!CanBePiped<char (&&)[10], decltype(std::views::split('x'))>);47static_assert(!CanBePiped<NotAView, decltype(std::views::split('x'))>);48 49static_assert(std::same_as<decltype(std::views::split), decltype(std::ranges::views::split)>);50 51constexpr bool test() {52 std::string_view input = "abc";53 std::string_view sep = "a";54 55 // Test that `std::views::split` is a range adaptor.56 57 // Test `views::split(input, sep)`.58 {59 SomeView view(input);60 61 using Result = std::ranges::split_view<SomeView, std::string_view>;62 std::same_as<Result> decltype(auto) result = std::views::split(view, sep);63 assert(result.base().begin() == input.begin());64 assert(result.base().end() == input.end());65 }66 67 // Test `views::split(sep)(input)`.68 {69 SomeView view(input);70 71 using Result = std::ranges::split_view<SomeView, std::string_view>;72 std::same_as<Result> decltype(auto) result = std::views::split(sep)(view);73 assert(result.base().begin() == input.begin());74 assert(result.base().end() == input.end());75 }76 77 // Test `view | views::split`.78 {79 SomeView view(input);80 81 using Result = std::ranges::split_view<SomeView, std::string_view>;82 std::same_as<Result> decltype(auto) result = view | std::views::split(sep);83 assert(result.base().begin() == input.begin());84 assert(result.base().end() == input.end());85 }86 87 // Test `adaptor | views::split`.88 {89 SomeView view(input);90 auto f = [](char c) { return c; };91 auto partial = std::views::transform(f) | std::views::split(sep);92 93 using Result = std::ranges::split_view<std::ranges::transform_view<SomeView, decltype(f)>, std::string_view>;94 std::same_as<Result> decltype(auto) result = partial(view);95 assert(result.base().base().begin() == input.begin());96 assert(result.base().base().end() == input.end());97 }98 99 // Test `views::split | adaptor`.100 {101 SomeView view(input);102 auto f = [](auto v) { return v; };103 auto partial = std::views::split(sep) | std::views::transform(f);104 105 using Result = std::ranges::transform_view<std::ranges::split_view<SomeView, std::string_view>, decltype(f)>;106 std::same_as<Result> decltype(auto) result = partial(view);107 assert(result.base().base().begin() == input.begin());108 assert(result.base().base().end() == input.end());109 }110 111 // Test that one can call `std::views::split` with arbitrary stuff, as long as we112 // don't try to actually complete the call by passing it a range.113 //114 // That makes no sense and we can't do anything with the result, but it's valid.115 {116 struct X { };117 [[maybe_unused]] auto partial = std::views::split(X{});118 }119 120 return true;121}122 123int main(int, char**) {124 test();125 static_assert(test());126 127 return 0;128}129