Function splice_joins

lib/sqlalchemy/sql/util.py:855–881

(
    left: Optional[FromClause],
    right: Optional[FromClause],
    stop_on: Optional[FromClause] = None,
)

def splice_joins(
    left: Optional[FromClause],
    right: Optional[FromClause],
    stop_on: Optional[FromClause] = None,
) -> Optional[FromClause]:
    if left is None:
        return right

    stack: List[Tuple[Optional[FromClause], Optional[Join]]] = [(right, None)]

    adapter = ClauseAdapter(left)
    ret = None
    while stack:
        right, prevright = stack.pop()
        if isinstance(right, Join) and right is not stop_on:
            right = right._clone()
            right.onclause = adapter.traverse(right.onclause)
            stack.append((right.left, right))
        else:
            right = adapter.traverse(right)
        if prevright is not None:
            assert right is not None
            prevright.left = right
        if ret is None:
            ret = right

    return ret


@overload