rust-lang / rust-lang/rust-clippy

Lint when `>` or `>=` is used i.e. compared values are not listed in (number line) order

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A-lint
Dominant language
Rust
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Description

What it does

Check that < and <= are used rather than > or >= so that compared values are listed in order.

Advantage
Drawbacks
  • Its rather opinionated so should probably be allow by default style/pedantic lint
  • inversion might not be possible if only the PartialEq impl for one direction is implemented, so it might need to be limited to cases where the operands implement Eq
Example

Could be written as:

if val >= min && max >= val {
    // do something
}
if min <= val && val <= max {
    // do something
}

Preferably it would also recognize common operands so that

if val <= max && min <= val {
    // do something
}
if max <= val || val <= min {
    // do something
}

would become

if min <= val && val <= max {
    // do something
}
if val <= min && max <= val {
    // do something
}

i.e. for && move common value to the operator and for || move common value away from the operator

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

No source file, test, or entry point is named. Start from the comparison examples in this issue and define the supported operand and Eq cases; done means the requested forms are diagnosed and the suggested rewrites preserve the stated ordering for && and ||.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
tooling
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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