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Diffstat (limited to 'src/boost/libs/utility/test/initialized_test.cpp')
-rw-r--r-- | src/boost/libs/utility/test/initialized_test.cpp | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/src/boost/libs/utility/test/initialized_test.cpp b/src/boost/libs/utility/test/initialized_test.cpp new file mode 100644 index 000000000..0b8852f12 --- /dev/null +++ b/src/boost/libs/utility/test/initialized_test.cpp @@ -0,0 +1,116 @@ +// Copyright 2010, Niels Dekker. +// +// Distributed under the Boost Software License, Version 1.0. (See +// accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt) +// +// Test program for boost::initialized<T>. +// +// 2 May 2010 (Created) Niels Dekker + +#include <boost/utility/value_init.hpp> +#include <boost/core/lightweight_test.hpp> + +#include <string> + +namespace +{ + // Typical use case for boost::initialized<T>: A generic class that + // holds a value of type T, which must be initialized by either + // value-initialization or direct-initialization. + template <class T> class key_value_pair + { + std::string m_key; + boost::initialized<T> m_value; + public: + + // Value-initializes the object held by m_value. + key_value_pair() { } + + // Value-initializes the object held by m_value. + explicit key_value_pair(const std::string& key) + : + m_key(key) + { + } + + // Direct-initializes the object held by m_value. + key_value_pair(const std::string& key, const T& value) + : + m_key(key), m_value(value) + { + } + + const T& get_value() const + { + return m_value; + } + }; + + + // Tells whether the argument is value-initialized. + bool is_value_initialized(const int& arg) + { + return arg == 0; + } + + + // Tells whether the argument is value-initialized. + bool is_value_initialized(const std::string& arg) + { + return arg.empty(); + } + + struct foo + { + int data; + }; + + bool operator==(const foo& lhs, const foo& rhs) + { + return lhs.data == rhs.data; + } + + + // Tells whether the argument is value-initialized. + bool is_value_initialized(const foo& arg) + { + return arg.data == 0; + } + + + template <class T> + void test_key_value_pair(const T& magic_value) + { + // The value component of a default key_value_pair must be value-initialized. + key_value_pair<T> default_key_value_pair; + BOOST_TEST( is_value_initialized(default_key_value_pair.get_value() ) ); + + // The value component of a key_value_pair that only has its key explicitly specified + // must also be value-initialized. + BOOST_TEST( is_value_initialized(key_value_pair<T>("key").get_value()) ); + + // However, the value component of the following key_value_pair must be + // "magic_value", as it must be direct-initialized. + BOOST_TEST( key_value_pair<T>("key", magic_value).get_value() == magic_value ); + } +} + + +// Tests boost::initialize for a fundamental type, a type with a +// user-defined constructor, and a user-defined type without +// a user-defined constructor. +int main() +{ + + const int magic_number = 42; + test_key_value_pair(magic_number); + + const std::string magic_string = "magic value"; + test_key_value_pair(magic_string); + + const foo magic_foo = { 42 }; + test_key_value_pair(magic_foo); + + return boost::report_errors(); +} |