def parents()

in sapp/ui/interactive.py [0:0]
37 lines of code
9 McCabe index (conditional complexity)

    def parents(self) -> None:
        self._verify_entrypoint_selected()
        current_trace_tuple = self.trace_tuples[self.current_trace_frame_index]

        # Don't allow calling from the leaf node in a trace. Instead, call
        # parents() from the placeholder of the caller of the leaf node.
        if current_trace_tuple.trace_frame.is_leaf():
            raise UserError("Try running from a non-leaf node.")

        # Backwards trace checks against the given frame's _caller_.
        # If we have A->B as a placeholder, we want parents that call A, since A
        #   is what is displayed in the trace.
        # If we have A->B as a non-placeholder, we want parents that call B,
        #   since B is what is displayed in the trace. So we go to (A->B)'s child
        #   B->C, and look for frames that call B.
        if not current_trace_tuple.placeholder:
            delta_from_child = -1 if self._is_before_root() else 1
            current_trace_tuple = self.trace_tuples[
                self.current_trace_frame_index + delta_from_child
            ]

        with self.db.make_session() as session:
            if current_trace_tuple.trace_frame.kind == TraceKind.POSTCONDITION:
                leaf_kind = self.sources
            elif current_trace_tuple.trace_frame.kind == TraceKind.PRECONDITION:
                leaf_kind = self.sinks
            else:
                assert (
                    current_trace_tuple.trace_frame.kind == TraceKind.POSTCONDITION
                    or current_trace_tuple.trace_frame.kind == TraceKind.PRECONDITION
                )

            parent_trace_frames = trace.next_frames(
                session,
                current_trace_tuple.trace_frame,
                # pyre-fixme[61]: `leaf_kind` may not be initialized here.
                leaf_kind,
                set(),
                self._current_run_id,
                backwards=True,
            )
        if len(parent_trace_frames) == 0:
            print(
                f"No parents calling [{current_trace_tuple.trace_frame.caller} "
                f": {current_trace_tuple.trace_frame.caller_port}]."
            )
            return

        parent_trace_frame = self._select_parent_trace_frame(parent_trace_frames)

        self._update_trace_tuples_new_parent(parent_trace_frame)
        self.trace()