问题重现

给菜单做递归数组的反序列化遇到的问题，结构大致如下，报错信息附在文末。

#[derive(Deserialize)]
struct Menu {
    title: String,
    url: String,
    children: Vec<Self>,
}

解决方案

这是一个类型识别的 bug，参见 issue #1565。

只需要把 children: Vec<Self>, 改成 children: Vec<Menu>, 就可以了，上上周已经有人发了 Pull Request #1830 ，我还没有升级，估计新版已经修复了此问题。

报错信息

error[E0277]: the trait bound `file::menu::_IMPL_DESERIALIZE_FOR_SiteMenu::<impl common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'de> for file::menu::SiteMenu>::deserialize::__Visitor<'de>: common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'_>` is not satisfied
  --> src\file\menu.rs:13:5
   |
13 |     children: Vec<Self>,
   |     ^^^^^^^^ the trait `common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'_>` is not implemented for `file::menu::_IMPL_DESERIALIZE_FOR_SiteMenu::<impl common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'de> for file::menu::SiteMenu>::deserialize::__Visitor<'de>`
   |
   = note: required because of the requirements on the impl of `common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'_>` for `std::vec::Vec<file::menu::_IMPL_DESERIALIZE_FOR_SiteMenu::<impl common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'de> for file::menu::SiteMenu>::deserialize::__Visitor<'de>>`
   = note: required by `common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::de::SeqAccess::next_element`

error[E0308]: mismatched types
 --> src\file\menu.rs:9:21
  |
9 | #[derive(Serialize, Deserialize, Clone)]
  |                     ^^^^^^^^^^^ expected struct `file::menu::SiteMenu`, found struct `file::menu::_IMPL_DESERIALIZE_FOR_SiteMenu::<impl common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'de> for file::menu::SiteMenu>::deserialize::__Visitor`
  |
  = note: expected struct `std::vec::Vec<file::menu::SiteMenu>`
             found struct `std::vec::Vec<file::menu::_IMPL_DESERIALIZE_FOR_SiteMenu::<impl common::config::_IMPL_DESERIALIZE_FOR_Menus::_serde::Deserialize<'de> for file::menu::SiteMenu>::deserialize::__Visitor<'_>>`
  = note: this error originates in a derive macro (in Nightly builds, run with -Z macro-backtrace for more info)