The useless attribute lint doesn't put the ! in the right place.

When the useless_attribute lint is activated, it says that you most likely forgot an exclamation mark (!). While this is true, it also suggests to stick the ! in the middle of the attribute:

warning: useless lint attribute, #[warn(useless_attribute)] on by default
 --> src/lib.rs:1:38
  |
1 | #[cfg_attr(feature = "cargo-clippy", allow(new_without_default))]
  |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
help: if you just forgot a `!`, use
  | #[cfg_attr(feature = "cargo-clippy", a!llow(new_without_default))]
  = help: for further information visit https://github.com/Manishearth/rust-clippy/wiki#useless_attribute

The correct response should be to suggest adding it after the #
I'm using the latest clippy on the latest nightly Rust.

Reproduce the useless_attribute diagnostic from the issue using the cfg_attr example in src/lib.rs with the latest Clippy and Rust nightly. Trace the useless_attribute lint's help suggestion and update its reported insertion point so the ! is recommended after #; done when the diagnostic shows the corrected placement.