Add test/quick.cpp

test/Jamfile.v2

@@ -108,3 +108,5 @@ test-suite unordered-exception
             <define>BOOST_UNORDERED_SWAP_METHOD=2 ]
         [ run exception/merge_exception_tests.cpp framework ]
     ;
+
+run quick.cpp ;

test/quick.cpp

@@ -0,0 +1,19 @@
+// Copyright 2022 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/unordered_map.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <string>
+
+int main()
+{
+    boost::unordered_map<std::string, int> map;
+
+    map[ "2" ] = 2;
+
+    BOOST_TEST_EQ( map[ "1" ], 0 );
+    BOOST_TEST_EQ( map[ "2" ], 2 );
+
+    return boost::report_errors();
+}