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| author | Lexi Winter <lexi@le-fay.org> | 2025-06-29 19:25:29 +0100 |
|---|---|---|
| committer | Lexi Winter <lexi@le-fay.org> | 2025-06-29 19:25:29 +0100 |
| commit | bc524d70253a4ab2fe40c3ca3e5666e267c0a4d1 (patch) | |
| tree | 1e629e7b46b1d9972a973bc93fd100bcebd395be /src/catch2/generators/catch_generators_adapters.hpp | |
| download | nihil-vendor/catch2.tar.gz nihil-vendor/catch2.tar.bz2 | |
import catch2 3.8.1vendor/catch2/3.8.1vendor/catch2
Diffstat (limited to 'src/catch2/generators/catch_generators_adapters.hpp')
| -rw-r--r-- | src/catch2/generators/catch_generators_adapters.hpp | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/src/catch2/generators/catch_generators_adapters.hpp b/src/catch2/generators/catch_generators_adapters.hpp new file mode 100644 index 0000000..d5fc1e1 --- /dev/null +++ b/src/catch2/generators/catch_generators_adapters.hpp @@ -0,0 +1,241 @@ + +// Copyright Catch2 Authors +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE.txt or copy at +// https://www.boost.org/LICENSE_1_0.txt) + +// SPDX-License-Identifier: BSL-1.0 +#ifndef CATCH_GENERATORS_ADAPTERS_HPP_INCLUDED +#define CATCH_GENERATORS_ADAPTERS_HPP_INCLUDED + +#include <catch2/generators/catch_generators.hpp> +#include <catch2/internal/catch_meta.hpp> +#include <catch2/internal/catch_move_and_forward.hpp> + +#include <cassert> + +namespace Catch { +namespace Generators { + + template <typename T> + class TakeGenerator final : public IGenerator<T> { + GeneratorWrapper<T> m_generator; + size_t m_returned = 0; + size_t m_target; + public: + TakeGenerator(size_t target, GeneratorWrapper<T>&& generator): + m_generator(CATCH_MOVE(generator)), + m_target(target) + { + assert(target != 0 && "Empty generators are not allowed"); + } + T const& get() const override { + return m_generator.get(); + } + bool next() override { + ++m_returned; + if (m_returned >= m_target) { + return false; + } + + const auto success = m_generator.next(); + // If the underlying generator does not contain enough values + // then we cut short as well + if (!success) { + m_returned = m_target; + } + return success; + } + }; + + template <typename T> + GeneratorWrapper<T> take(size_t target, GeneratorWrapper<T>&& generator) { + return GeneratorWrapper<T>(Catch::Detail::make_unique<TakeGenerator<T>>(target, CATCH_MOVE(generator))); + } + + + template <typename T, typename Predicate> + class FilterGenerator final : public IGenerator<T> { + GeneratorWrapper<T> m_generator; + Predicate m_predicate; + public: + template <typename P = Predicate> + FilterGenerator(P&& pred, GeneratorWrapper<T>&& generator): + m_generator(CATCH_MOVE(generator)), + m_predicate(CATCH_FORWARD(pred)) + { + if (!m_predicate(m_generator.get())) { + // It might happen that there are no values that pass the + // filter. In that case we throw an exception. + auto has_initial_value = next(); + if (!has_initial_value) { + Detail::throw_generator_exception("No valid value found in filtered generator"); + } + } + } + + T const& get() const override { + return m_generator.get(); + } + + bool next() override { + bool success = m_generator.next(); + if (!success) { + return false; + } + while (!m_predicate(m_generator.get()) && (success = m_generator.next()) == true); + return success; + } + }; + + + template <typename T, typename Predicate> + GeneratorWrapper<T> filter(Predicate&& pred, GeneratorWrapper<T>&& generator) { + return GeneratorWrapper<T>(Catch::Detail::make_unique<FilterGenerator<T, Predicate>>(CATCH_FORWARD(pred), CATCH_MOVE(generator))); + } + + template <typename T> + class RepeatGenerator final : public IGenerator<T> { + static_assert(!std::is_same<T, bool>::value, + "RepeatGenerator currently does not support bools" + "because of std::vector<bool> specialization"); + GeneratorWrapper<T> m_generator; + mutable std::vector<T> m_returned; + size_t m_target_repeats; + size_t m_current_repeat = 0; + size_t m_repeat_index = 0; + public: + RepeatGenerator(size_t repeats, GeneratorWrapper<T>&& generator): + m_generator(CATCH_MOVE(generator)), + m_target_repeats(repeats) + { + assert(m_target_repeats > 0 && "Repeat generator must repeat at least once"); + } + + T const& get() const override { + if (m_current_repeat == 0) { + m_returned.push_back(m_generator.get()); + return m_returned.back(); + } + return m_returned[m_repeat_index]; + } + + bool next() override { + // There are 2 basic cases: + // 1) We are still reading the generator + // 2) We are reading our own cache + + // In the first case, we need to poke the underlying generator. + // If it happily moves, we are left in that state, otherwise it is time to start reading from our cache + if (m_current_repeat == 0) { + const auto success = m_generator.next(); + if (!success) { + ++m_current_repeat; + } + return m_current_repeat < m_target_repeats; + } + + // In the second case, we need to move indices forward and check that we haven't run up against the end + ++m_repeat_index; + if (m_repeat_index == m_returned.size()) { + m_repeat_index = 0; + ++m_current_repeat; + } + return m_current_repeat < m_target_repeats; + } + }; + + template <typename T> + GeneratorWrapper<T> repeat(size_t repeats, GeneratorWrapper<T>&& generator) { + return GeneratorWrapper<T>(Catch::Detail::make_unique<RepeatGenerator<T>>(repeats, CATCH_MOVE(generator))); + } + + template <typename T, typename U, typename Func> + class MapGenerator final : public IGenerator<T> { + // TBD: provide static assert for mapping function, for friendly error message + GeneratorWrapper<U> m_generator; + Func m_function; + // To avoid returning dangling reference, we have to save the values + T m_cache; + public: + template <typename F2 = Func> + MapGenerator(F2&& function, GeneratorWrapper<U>&& generator) : + m_generator(CATCH_MOVE(generator)), + m_function(CATCH_FORWARD(function)), + m_cache(m_function(m_generator.get())) + {} + + T const& get() const override { + return m_cache; + } + bool next() override { + const auto success = m_generator.next(); + if (success) { + m_cache = m_function(m_generator.get()); + } + return success; + } + }; + + template <typename Func, typename U, typename T = FunctionReturnType<Func, U>> + GeneratorWrapper<T> map(Func&& function, GeneratorWrapper<U>&& generator) { + return GeneratorWrapper<T>( + Catch::Detail::make_unique<MapGenerator<T, U, Func>>(CATCH_FORWARD(function), CATCH_MOVE(generator)) + ); + } + + template <typename T, typename U, typename Func> + GeneratorWrapper<T> map(Func&& function, GeneratorWrapper<U>&& generator) { + return GeneratorWrapper<T>( + Catch::Detail::make_unique<MapGenerator<T, U, Func>>(CATCH_FORWARD(function), CATCH_MOVE(generator)) + ); + } + + template <typename T> + class ChunkGenerator final : public IGenerator<std::vector<T>> { + std::vector<T> m_chunk; + size_t m_chunk_size; + GeneratorWrapper<T> m_generator; + bool m_used_up = false; + public: + ChunkGenerator(size_t size, GeneratorWrapper<T> generator) : + m_chunk_size(size), m_generator(CATCH_MOVE(generator)) + { + m_chunk.reserve(m_chunk_size); + if (m_chunk_size != 0) { + m_chunk.push_back(m_generator.get()); + for (size_t i = 1; i < m_chunk_size; ++i) { + if (!m_generator.next()) { + Detail::throw_generator_exception("Not enough values to initialize the first chunk"); + } + m_chunk.push_back(m_generator.get()); + } + } + } + std::vector<T> const& get() const override { + return m_chunk; + } + bool next() override { + m_chunk.clear(); + for (size_t idx = 0; idx < m_chunk_size; ++idx) { + if (!m_generator.next()) { + return false; + } + m_chunk.push_back(m_generator.get()); + } + return true; + } + }; + + template <typename T> + GeneratorWrapper<std::vector<T>> chunk(size_t size, GeneratorWrapper<T>&& generator) { + return GeneratorWrapper<std::vector<T>>( + Catch::Detail::make_unique<ChunkGenerator<T>>(size, CATCH_MOVE(generator)) + ); + } + +} // namespace Generators +} // namespace Catch + + +#endif // CATCH_GENERATORS_ADAPTERS_HPP_INCLUDED |
