Wrong position of inserted `&self` in suggestion of compile error

[rhysd]

I tried this code:

struct X(i32);

impl X {
    pub(crate) fn f() {
        self.0
    }
}

fn main() {}

I expected to see this happen: Correct compile error due to lack of self receiver.

Instead, this happened: Compile error happens. But its suggestion is not correct:

error[E0424]: expected value, found module `self`
 --> bar.rs:5:9
  |
4 |     pub(crate) fn f() {
  |                   - this function doesn't have a `self` parameter
5 |         self.0
  |         ^^^^ `self` value is a keyword only available in methods with a `self` parameter
  |
help: add a `self` receiver parameter to make the associated `fn` a method
  |
4 |     pub(&selfcrate) fn f() {
  |         +++++

error: aborting due to previous error

For more information about this error, try `rustc --explain E0424`.

&self is inserted to just after first (. But in this case, the first ( is not for method parameter. So the position is not correct.

4 |     pub(&selfcrate) fn f() {

This line should be:

4 |     pub(crate) fn f(&self) {

Meta

rustc --version --verbose:

rustc 1.57.0 (f1edd0429 2021-11-29)
binary: rustc
commit-hash: f1edd0429582dd29cccacaf50fd134b05593bd9c
commit-date: 2021-11-29
host: x86_64-apple-darwin
release: 1.57.0
LLVM version: 13.0.0

[rhysd]

I think the logic here causes this issue:

rust/compiler/rustc_resolve/src/late/diagnostics.rs

Lines 295 to 309 in 4a66a70

	let (span, sugg) = fn_kind
	.decl()
	.inputs
	.get(0)
	.map(|p| (p.span.shrink_to_lo(), "&self, "))
	.unwrap_or_else(|| {
	(
	self.r
	.session
	.source_map()
	.span_through_char(*span, '(')
	.shrink_to_hi(),
	"&self",
	)
	});

[bugadani]

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