Add `comparison_to_empty`

[0xLucqs]

What it does

Checks for comparing to an empty slice such as [], and suggests using .is_empty() where applicable.

Why is this bad?

Some structures can answer .is_empty() much faster than checking for equality. So it is good to get into the habit of using .is_empty(), and having it is cheap. Besides, it makes the intent clearer than a manual comparison in some contexts.

Example

if s == ArrayTrait::new() {
    ..
}

Use instead:

if arr.is_empty() {
    ..
}

[0xLucqs]

hey @Benjtalkshow wanna try this one ?

[onlydustapp[bot]]

Hey @SridharVadla45! Thanks for showing interest. We've created an application for you to contribute to Cairo lint. Go check it out on OnlyDust!

[0xLucqs]

sure any idea on how to proceed ?

[BernalHQ]

Hi @0xLucqs, can i try this.

first i m going to identify which structs in Cairo support is_empty. Once identified, I’ll implement the logic to catch those cases and suggest fixes. Lastly, I’ll write some tests.

[onlydustapp[bot]]

Hey @BernalHQ! Thanks for showing interest. We've created an application for you to contribute to Cairo lint. Go check it out on OnlyDust!

[0xLucqs]

Hey @BernalHQ can you pick another issue plz (or if @SridharVadla45 doesn’t answer in the coming days you can take it)

[BernalHQ]

Ok, i going to looking another issue, and i can do It, if dont answer It.

[jcampos2907]

I am applying to this issue via OnlyDust platform.

My background and how it can be leveraged

Ive been leaning rust for the past year and looking to get a good first issue

[lauchaves]

Hey @0xLucqs is this one available? If so, may I work on this! :D

[onlydustapp[bot]]

Hey @lauchaves! Thanks for showing interest. We've created an application for you to contribute to Cairo lint. Go check it out on OnlyDust!

[MariangelaNM]

I am applying to this issue via OnlyDust platform.

Hi @0xLucqs, is there an opportunity for me to work on this project again? I previously worked on it and would love to contribute further.

[JoE11-y]

Hey @0xLucqs, I’d love to take a look at this too.

[augustin-v]

I am applying to this issue via OnlyDust platform.

My background and how it can be leveraged

I am an enthusiastic self-taught developer, that learnt Rust as my first language. With hands-on experience optimizing gas usage in projects like Node Guardians exercises (thinking in cairo, brainfvckvm). Which helped me learn how to write optimized code

How I plan on tackling this issue

As I have already reviewed the codebase, I would first create a linting rule that flags these comparisons and suggests using .is_empty() instead, and then test to ensure the rule correctly identifies and suggests improvements.

[od-hunter]

Hi @0xLucqs , please can I be assigned please? This would be my first time contributing to this repo and I’d love to be given the opportunity.

[onlydustapp[bot]]

Hey @od-hunter! Thanks for showing interest. We've created an application for you to contribute to Cairo lint. Go check it out on OnlyDust!

[Benjtalkshow]

hey @Benjtalkshow wanna try this one ?

Hey @0xLucqs I can handle the issue. I wanna try it

[0xLucqs]

did anyone start anything ? In case no i this issue will be paused

[Benjtalkshow]

did anyone start anything ? In case no i this issue will be paused

Hey @0xLucqs , I already started working on it. Should i continue?

[0xLucqs]

can you open a pr to show me what you have ?

[SumitGoulikar]

Hi @0xLucqs , can I be assigned please? This would be my first time contributing to this repository and I would love to be given this opportunity.

[Benjtalkshow]

can you open a pr to show me what you have ?

Alright

[Benjtalkshow]

Hello @0xLucqs , I just made a draft PR regarding this issue. I will appreciate it if this issue is assigned to me. Thanks

[vic-Gray]

I am applying to this issue via OnlyDust platform.

My background and how it can be leveraged

I have experience optimizing Rust code for performance and clarity, focusing on efficient and maintainable solutions to address challenges.

How I plan on tackling this issue

The check compares a slice to an empty one, recommending .is_empty() for better performance and clarity. I'd replace manual comparisons with .is_empty() to improve the code.