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70 lines
2.0 KiB
C++
70 lines
2.0 KiB
C++
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// Test free function contracts.
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#include "../aux_/oteststream.hpp"
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#include "../aux_/cpcnt.hpp"
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#include <boost/contract/free_function.hpp>
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#include <boost/contract/oldof.hpp>
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#include <boost/contract/assert.hpp>
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#include <boost/contract/guard.hpp>
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#include <boost/shared_ptr.hpp>
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#include <boost/detail/lightweight_test.hpp>
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#include <sstream>
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boost::contract::aux::test::oteststream out;
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struct x_tag; typedef boost::contract::aux::test::cpcnt<x_tag, int> x_type;
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struct y_tag; typedef boost::contract::aux::test::cpcnt<y_tag, int> y_type;
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bool swap(x_type& x, y_type& y) {
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bool result;
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boost::shared_ptr<x_type const> old_x =
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BOOST_CONTRACT_OLDOF(x_type::eval(x));
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boost::shared_ptr<y_type const> old_y =
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BOOST_CONTRACT_OLDOF(y_type::eval(y));
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boost::contract::guard c = boost::contract::free_function()
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.precondition([&] {
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out << "swap::pre" << std::endl;
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BOOST_CONTRACT_ASSERT(x.value != y.value);
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})
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.postcondition([&] {
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out << "swap::post" << std::endl;
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BOOST_CONTRACT_ASSERT(x.value == old_y->value);
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BOOST_CONTRACT_ASSERT(y.value == old_x->value);
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BOOST_CONTRACT_ASSERT(result == (old_x->value != old_y->value));
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})
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;
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out << "swap::body" << std::endl;
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if(x.value == y.value) return result = false;
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int save_x = x.value;
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x.value = y.value;
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y.value = save_x;
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return result = true;
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}
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int main() {
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std::ostringstream ok;
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x_type x; x.value = 123;
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y_type y; y.value = 456;
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out.str("");
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bool r = swap(x, y);
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ok.str(""); ok
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<< "swap::pre" << std::endl
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<< "swap::body" << std::endl
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<< "swap::post" << std::endl
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;
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BOOST_TEST(out.eq(ok.str()));
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BOOST_TEST(r);
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BOOST_TEST_EQ(x.value, 456);
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BOOST_TEST_EQ(y.value, 123);
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BOOST_TEST_EQ(x.copies(), 1); BOOST_TEST_EQ(x.evals(), 1);
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BOOST_TEST_EQ(y.copies(), 1); BOOST_TEST_EQ(y.evals(), 1);
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return boost::report_errors();
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}
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