Add array_access_test.cpp

test/array_access_test.cpp

@@ -0,0 +1,117 @@
+// Copyright 2025 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt)
+
+#define BOOST_ENABLE_ASSERT_HANDLER
+
+#include <boost/array.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <cstddef>
+
+struct assertion_failure
+{
+};
+
+namespace boost
+{
+
+void assertion_failed( char const* /*expr*/, char const* /*function*/, char const* /*file*/, long /*line*/ )
+{
+    throw assertion_failure();
+}
+
+void assertion_failed_msg( char const* /*expr*/, char const* /*msg*/, char const* /*function*/, char const* /*file*/, long /*line*/ )
+{
+    throw assertion_failure();
+}
+
+} // namespace boost
+
+template<class T, std::size_t N> void test()
+{
+    {
+        boost::array<T, N> a = {{}};
+
+        T* p1 = a.data();
+
+        for( std::size_t i = 0; i < N; ++i )
+        {
+            T* p2 = &a[ i ];
+            T* p3 = &a.at( i );
+
+            BOOST_TEST_EQ( p2, p1 + i );
+            BOOST_TEST_EQ( p3, p1 + i );
+        }
+
+        {
+            T* p2 = &a.front();
+            T* p3 = &a.back();
+
+            BOOST_TEST_EQ( p2, p1 + 0 );
+            BOOST_TEST_EQ( p3, p1 + N - 1 );
+        }
+
+        BOOST_TEST_THROWS( a.at( N ), std::out_of_range );
+        BOOST_TEST_THROWS( a[ N ], assertion_failure );
+    }
+
+    {
+        boost::array<T, N> const a = {{}};
+
+        T const* p1 = a.data();
+
+        for( std::size_t i = 0; i < N; ++i )
+        {
+            T const* p2 = &a[ i ];
+            T const* p3 = &a.at( i );
+
+            BOOST_TEST_EQ( p2, p1 + i );
+            BOOST_TEST_EQ( p3, p1 + i );
+        }
+
+        {
+            T const* p2 = &a.front();
+            T const* p3 = &a.back();
+
+            BOOST_TEST_EQ( p2, p1 + 0 );
+            BOOST_TEST_EQ( p3, p1 + N - 1 );
+        }
+
+        BOOST_TEST_THROWS( a.at( N ), std::out_of_range );
+        BOOST_TEST_THROWS( a[ N ], assertion_failure );
+    }
+}
+
+template<class T> void test2()
+{
+    {
+        boost::array<T, 0> a = {};
+
+        BOOST_TEST_THROWS( a.at( 0 ), std::out_of_range );
+        BOOST_TEST_THROWS( a[ 0 ], std::out_of_range );
+        BOOST_TEST_THROWS( a.front(), std::out_of_range );
+        BOOST_TEST_THROWS( a.back(), std::out_of_range );
+    }
+
+    {
+        boost::array<T, 0> const a = {};
+
+        BOOST_TEST_THROWS( a.at( 0 ), std::out_of_range );
+        BOOST_TEST_THROWS( a[ 0 ], std::out_of_range );
+        BOOST_TEST_THROWS( a.front(), std::out_of_range );
+        BOOST_TEST_THROWS( a.back(), std::out_of_range );
+    }
+}
+
+int main()
+{
+    test<int, 1>();
+    test<int, 7>();
+
+    test<int const, 1>();
+    test<int const, 7>();
+
+    test2<int>();
+
+    return boost::report_errors();
+}