Class FilterGenerator
Synopsis
#include <include/internal/catch_generators_generic.hpp>
template <typename T, typename Predicate>
class FilterGenerator : public IGenerator<T>
Description
No description yet.
Mentioned in
- Writing tests / Data Generators / Provided generators
Inheritance
Ancestors: IGenerator
Methods
| FilterGenerator | ||
| get | ||
| next |
Source
Lines 53-85 in include/internal/catch_generators_generic.hpp.
template <typename T, typename Predicate>
class FilterGenerator : public IGenerator<T> {
GeneratorWrapper<T> m_generator;
Predicate m_predicate;
public:
template <typename P = Predicate>
FilterGenerator(P&& pred, GeneratorWrapper<T>&& generator):
m_generator(std::move(generator)),
m_predicate(std::forward<P>(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) {
Catch::throw_exception(GeneratorException("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;
}
};