threadtree.py 文件源码

def iter_thread_frames():
        main_thread_frame = None
        for ident, frame in sys._current_frames().items():
            if IDENT_TO_UUID.get(ident) == MAIN_UUID:
                main_thread_frame = frame
                # the MainThread should be shown in it's "greenlet" version
                continue
            yield ident, frame

        for thread in threading.enumerate():
            if not getattr(thread, '_greenlet', None):
                # some inbetween state, before greenlet started or after it died?...
                pass
            elif thread._greenlet.gr_frame:
                yield thread.ident, thread._greenlet.gr_frame
            else:
                # a thread with greenlet but without gr_frame will be fetched from sys._current_frames
                # If we switch to another greenlet by the time we get there we will get inconsistent dup of threads.
                # TODO - make best-effort attempt to show coherent thread dump
                yield thread.ident, main_thread_frame