CppClass.add_output_stream() documentation and unit tests.

pybindgen/cppclass.py

@@ -1085,6 +1085,17 @@ public:
             self.has_trivial_constructor = True
 
     def add_output_stream_operator(self):
+        """
+        Add str() support based on C++ output stream operator.
+
+        Calling this method enables wrapping of an assumed to be defined operator function::
+
+             std::ostream & operator << (std::ostream &, MyClass const &);
+
+        The wrapper will be registered as an str() python operator,
+        and will call the C++ operator function to convert the value
+        to a string.
+        """
         self.has_output_stream_operator = True
 
     def add_constructor(self, *args, **kwargs):

pybindgen/gccxmlparser.py

@@ -1507,6 +1507,7 @@ pybindgen.settings.error_handler = ErrorHandler()
                             class_wrapper.ThisClassRefParameter("%s const &" % class_wrapper.full_name,
                                                                 'ctor_arg', is_const=True)])
         if has_output_stream_operator:
+            class_wrapper.add_output_stream_operator()
             pygen_sink.writeln("cls.add_output_stream_operator()")
 
 

tests/foo.h

@@ -49,6 +49,11 @@ public:
     virtual ~Foo() { Foo::instance_count--; }
 };
 
+inline std::ostream & operator << (std::ostream &os, Foo const &foo)
+{
+    os << foo.get_datum ();
+    return os;
+}
 
 class Zoo
 // -#- automatic_type_narrowing=True -#-

tests/foomodulegen.py

@@ -29,6 +29,7 @@ def my_module_gen(out_file):
     Foo.add_constructor([])
     Foo.add_method('get_datum', ReturnValue.new('std::string'), [])
     Foo.add_method('is_initialized', ReturnValue.new('bool'), [], is_const=True)
+    Foo.add_output_stream_operator()
 
     Zoo = mod.add_class('Zoo', automatic_type_narrowing=True)
     Zoo.add_constructor([Parameter.new('std::string', 'datum')])

tests/footest.py

@@ -710,5 +710,10 @@ class TestFoo(unittest.TestCase):
         expected = [1.0, 0.0, 0.0, 0.0, 1.0, 0.0]
         self.assertEqual(result, expected)
 
+    def test_output_stream(self):
+        f = foo.Foo("hello")
+        self.assertEqual(str(f), "hello")
+
+
 if __name__ == '__main__':
     unittest.main()