Tracking Issue: lints that lint against match and if-lets should be more consistent

[J-ZhengLi]

Description

there are lints that check (or at least should be checking) for match or if-let on Option or Result, such as [question_mark], which checks all combinations now.

But there are some lints that either checks only match exprs on Option and Result, or checks match and if-let on Options, which does not seems consistent, consider the same rules could be applied for both.

Here is a short list of lints that I found which has this problem (I didn't went into it enough so it's highly possible there are missing some lint, ping me to add them in):

Lint Name	What's Missing	PR #	Finished
manual_unwrap_or	linting for if-let expressions
manual_unwrap_or_default	linting for Result type
manual_let_else (somewhat belongs to this list... I think)	linting for Result type (The pat_and_expr_can_be_question_mark could use some improvement, since not only Options can use question mark, any types that impls Try trait can use it, like Result ofc)

Not in the list but could someone plz confirm that the problem which [if_let_mutex] trying to prevent can or cannot happen with match?

Version

No response

Additional Labels

@rustbot label +I-false-nagative +C-enhancement +good-first-issue

[J-ZhengLi]

(somewhat) related to the discussion in #12610

[rufevean]

Am i reproducing this issue correctly?

fn manual_unwrap_or_example(opt: option<i32>) -> i32 {
    if let some(val) = opt {
        val
    } else {
        0 
    }
}

fn main() {
    let opt_none: option<i32> = none;
    println!("{}", manual_unwrap_or_example(opt_none));
}

if we use

cargo clippy -- -D clippy::manual_unwrap_or

on this code, it shows no warning or error while it should be suggesting us to use unwrap_or () .

[J-ZhengLi]

Am i reproducing this issue correctly?

fn manual_unwrap_or_example(opt: option<i32>) -> i32 {
    if let some(val) = opt {
        val
    } else {
        0 
    }
}

fn main() {
    let opt_none: option<i32> = none;
    println!("{}", manual_unwrap_or_example(opt_none));
}

if we use

cargo clippy -- -D clippy::manual_unwrap_or

on this code, it shows no warning or error while it should be suggesting us to use unwrap_or () .

Yeah, except it should be some other value except 0 in the else branch. (This repro triggers manual_unwrap_or_default flawlessly, but changing the number doesn't triggers manual_unwrap_or, which is why I think they are inconsistent 😄 )