visualstudio_py_debugger.py 文件源码

def _stackless_schedule_cb(self, prev, next):
        current = stackless.getcurrent()
        if not current:
            return
        current_tf = current.trace_function

        try:
            current.trace_function = None
            self.stepping = STEPPING_NONE

            # If the current frame has no trace function, we may need to get it
            # from the previous frame, depending on how we ended up in the
            # callback.
            if current_tf is None:
                f_back = current.frame.f_back
                if f_back is not None:
                    current_tf = f_back.f_trace

            if next is not None:
                # Assign our trace function to the current stack
                f = next.frame
                if next is current:
                    f = f.f_back
                while f:
                    if isinstance(f, types.FrameType):
                        f.f_trace = self.trace_func
                    f = f.f_back
                next.trace_function = self.trace_func
        finally:
            current.trace_function = current_tf