Suggest dereferencing boolean reference when used in 'if'

[Aaron1011]

The following code:

fn take_bool(val: bool) {}

fn main() {
    let a = &true;
    if a {
        println!("Hello!");
    }
    take_bool(a)
}

gives the following errors:

error[E0308]: mismatched types
 --> src/main.rs:5:8
  |
5 |     if a {
  |        ^ expected bool, found &bool
  |
  = note: expected type `bool`
             found type `&bool`

error[E0308]: mismatched types
 --> src/main.rs:8:15
  |
8 |     take_bool(a)
  |               ^
  |               |
  |               expected bool, found &bool
  |               help: consider dereferencing the borrow: `*a`
  |
  = note: expected type `bool`
             found type `&bool`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0308`.
error: Could not compile `playground`.

Note that the first error is missing the "help: consider dereferencing the borrow: *a" suggestion.

For consistency, Rust should suggest dereferencing a boolean reference when used in an 'if' expression.

This issue has been assigned to @XiangQingW via this comment.

[Aaron1011]

@rustbot modify labels to +A-lint

[Aaron1011]

@rustbot modify labels to -A-lint +A-suggestion-diagnostics

[XiangQingW]

@Aaron1011 I'd love to be assigned to the issue.

[Aaron1011]

@XiangQingW: You can use @rustbot claim to assign the issue to yourself.

[rustbot]

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[rustbot]

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[XiangQingW]

@rustbot claim

[mayabyte]

Has a PR been submitted for this yet? I'm happy to take it if not

[XiangQingW]

Has a PR been submitted for this yet? I'm happy to take it if not
Hum... I'm working on this, and sorry for the delay because I was busy last several days.

[Aaron1011]

Fixed in #65150