Diagnostics incorrectly indicate a macro invocation when there's none

[marcospb19]

Sublime Text Version

Build 4155

Rust Enhanced Version

2.25.0

Operating system

Arch Linux

Steps to reproduce

1. Add this code:

fn f() -> impl Fn() {}

fn main() {}

2. Save the file.
3. You'll be shown the following diagnostics:

As pointed out by the white arrow I drew, there's a message that says "in this macro invocation", but there are no explicit macros.

Cargo's output:

error[E0277]: expected a `Fn<()>` closure, found `()`
 --> src/main.rs:1:11
  |
1 | fn f() -> impl Fn() {}
  |           ^^^^^^^^^ expected an `Fn<()>` closure, found `()`
  |
  = help: the trait `Fn<()>` is not implemented for `()`
  = note: wrap the `()` in a closure with no arguments: `|| { /* code */ }`

Output of cargo check --message-format json:

Expand me

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