extend buffer len

IPython/core/tests/test_debugger.py

@@ -379,6 +379,7 b' def _decorator_skip_setup():'
     child.expect("\n")
 
     child.timeout = 5 * IPYTHON_TESTING_TIMEOUT_SCALE
+    child.str_last_chars = 500
 
     dedented_blocks = [dedent(b).strip() for b in skip_decorators_blocks]
     in_prompt_number = 1