Rust Analyzer shows wrong warning SHA1 hasher finalize

[SamTV12345]

rust-analyzer version: (eg. output of "rust-analyzer: Show RA Version" command, accessible in VSCode via Ctrl/⌘+Shift+P)

rustc version: (eg. output of rustc -V) 1.70

relevant settings: (eg. client settings, or environment variables like CARGO, RUSTC, RUSTUP_HOME or CARGO_HOME): %

In IntelliJ the Rust plugin in version 0.4.197.5401-231 shows a warning when using the SHA-1 crate.

        let mut hasher = Sha1::new();

        hasher.update(non_hashed_string);

        let hashed_auth_key = format!("{:x}", hasher.finalize());

In this part of the code it complains that hasher.finalize() CtOutput<CoreWrapper<Sha1Core>> doesn't implement LowerHex (required by {:x}). The code compiles and it also works in my open source production environment.

[lowr]

In IntelliJ the Rust plugin in version 0.4.197.5401-231

This is rust-analyzer's repository, not intellij-rust's. Can you check if you're reporting rust-analyzer's issue or intellij-rust's issue?

[lnicola]

We don't show any errors, but we don't resolve Sha1::new, so there's still a bug related to this.

EDIT: <Sha1 as Digest>::new() works, but then we don't resolve update from the same trait.

use sha1::{Digest, Sha1};

fn main() {
    let mut hasher = <Sha1 as Digest>::new();

    hasher.update("afdfs");

    let hashed_auth_key = format!("{:x}", hasher.finalize());
    dbg!(hashed_auth_key);
}

[SamTV12345]

Thanks for taking a look at it 😄

[newpavlov]

Is it possible to bisect this? I think it's a relatively recent regression.

[lnicola]

The bug in my comment above is not a recent regression, but it was less noticeable before.

The "no such associated item" in RustCrypto/hashes#529 is a recently-added diagnostic that makes the bug more visible. We've just marked it as experimental so it will go away next week, but that doesn't fix the underlying problem.