Clippy · Correctness

Comparing two unit values

clippy::unit_cmp

Compare the values the expressions produce, not unit, which always compares equal.

Category: Correctness
Default level: warn
Tier: P1
Producer: Clippy
Diff scope: line

Not a defect when

The comparison is a test assertion such as assert_eq!(handler(), ()) written to pin that a call returns unit, where it checks nothing at runtime but documents the signature.

What it reads

Clippy, with the compiler behind it. The only pass that compiles.

Tier

Serious: worth interrupting other work for.

The tier bounds how severe a rule may be; its category bounds the tier.

Diff scope

The changed line itself.

What --scope contextual looks at to decide whether a change caused the finding.

Change it

Turn it off, or make it blocking, without touching the code it flags:

rust-doctor --rule clippy::unit_cmp=off .
rust-doctor --rule clippy::unit_cmp=error .

Set it once in rust-doctor.toml

Upstream