message: Remove outdated Rust compatibility code
diff: @@ -429,32 +429,3 @@ where
  })
  }
  }
  -
  -trait OptionInsert {
  - type T;
  - fn insert(&mut self, value: Self::T) -> &mut Self::T;
  -}
  -
  -// TODO: Remove when MSRV is >= 1.53.0.
  -//
  -/// Trait implementation to support Rust version < 1.53.0.
  -///
  -/// This is taken [from STD], further license information can be found in the [rust-lang/rust
  -/// repository].
  -///
  -///
  -/// [from STD]: https://github.com/rust-lang/rust/blob/6e0b554619a3bb7e75b3334e97f191af20ef5d76/library/core/src/option.rs#L829-L858
  -/// [rust-lang/rust repository]: https://github.com/rust-lang/rust/blob/master/LICENSE-MIT
  -impl<T> OptionInsert for Option<T> {
  - type T = T;
  -
  - fn insert(&mut self, value: T) -> &mut T {
  - *self = Some(value);
  -
  - match self {
  - Some(v) => v,
  - // SAFETY: the code above just filled the option
  - None => unsafe { std::hint::unreachable_unchecked() },
  - }
  - }
  -}
  