added tests demonstrating a bug in wxString::assign(itself)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@48214 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

tests/strings/strings.cpp

@@ -214,6 +214,10 @@ void StringTestCase::Extraction()
 
     #undef TEST_STARTS_WITH
 
+    rest = "Hello world";
+    CPPUNIT_ASSERT( rest.StartsWith("Hello ", &rest) );
+    WX_ASSERT_STR_EQUAL("world", rest);
+
     #define TEST_ENDS_WITH(suffix, correct_rest, result)                      \
         CPPUNIT_ASSERT_EQUAL(result, s.EndsWith(suffix, &rest));              \
         if ( result )                                                         \