inline.py 文件源码

def _handle_loop(node, state, ctx, visit_after, visiting_after, walk_field, **_):
    if not visiting_after:
        # Need to traverse fields explicitly since for the purposes of _replace_returns(),
        # the body of `orelse` field is not inside a loop.
        state = state.update(loop_nesting_ctr=state.loop_nesting_ctr + 1)
        state, new_body = walk_field(state, node.body, block_context=True)
        state = state.update(loop_nesting_ctr=state.loop_nesting_ctr - 1)
        state, new_orelse = walk_field(state, node.orelse, block_context=True)

        visit_after()
        return state, replace_fields(node, body=new_body, orelse=new_orelse)
    else:
        # If there was a return inside a loop, append a conditional break
        # to propagate the return otside all nested loops
        if state.return_inside_a_loop:
            new_nodes = [
                node,
                ast.If(
                    test=ast.Name(id=ctx.return_flag_var),
                    body=[ast.Break()],
                    orelse=[])]
        else:
            new_nodes = node

        # if we are at root level, reset the return-inside-a-loop flag
        if state.loop_nesting_ctr == 0:
            state = state.update(return_inside_a_loop=False)

        return state, new_nodes