`merge imports` and `unmerge use` deletes `$0` from code

When invoking a merge imports code action on the following code removes the first occurrence of $0 from the file. The same thing happens regardless of whether the two characters are in a comment or a string literal.

If there is no $0 in the file, the cursor is placed at the end of the file.

Other code actions such as remove unnecessary braces (around a use item) do not trigger the delete.

#![allow(unused_imports)]
#![allow(dead_code)]

mod x {
    pub struct A;
    pub struct B;
}

use x::A;
use x::B;

// Comment containing $0 sequence

fn main() {
    _s = "This $0 will be deleted on the next merge/unmerge code action.";
}

I have found this while looking into the internals and as far as I understand $0 is used to model where a cursor is for examples and tests. I'll try to figure out what's happening inside but any pointers would be appreciated.

rust-analyzer version: rust-analyzer version: 0.4.1408-standalone (a6603fc21 2023-02-16)

rustc version: rustc 1.67.1 (d5a82bbd2 2023-02-07)

relevant settings: Windows, VS Code, no special settings

Reproduce the merge imports and unmerge use code actions in VS Code with the provided Rust snippet, checking both the comment and string cases. Trace how $0 is handled for code-action examples and tests; done means the code actions no longer delete $0 or move the cursor unexpectedly, while other actions remain unaffected.