Extend unnecessary_unwrap to look for expect in addition to unwrap

[shepmaster]

changelog: Extend [`unnecessary_unwrap`] to also check for Option::expect and Result::expect. Also give code suggestions in some cases.

Fixes #7581

[rust-highfive]

r? @camsteffen

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[camsteffen]

You bumped into the stderr length limit. I think you can remove some of your tests. It isn't necessary to add an expect test for every unwrap test.

[shepmaster]

An actual code suggestion would be even better

Any tips on where to look for how to do that?

I haven't found any examples of how to suggest that a line of code be deleted.

if __option__.is_some() {
    let __var__ = __option__.unwrap();
}

Should be suggested to

if let Some(__var__) = __option__ {
}

So I'd need to:

1. track the target variable name (if there is one)
2. track if it's an Option or Result
3. write the if into an if-let, preserving the body
4. remove the redundant unwrap/expect expression / statement

[shepmaster]

You bumped into the stderr length limit. I think you can remove some of your tests.

Looks like the help caused this to happen again — any preferred tests I should remove this round?

[camsteffen]

For the code suggestion, I think it's okay to keep it simple and just make a suggestion to replace the if condition like if let Some(..) = __option__. So that is leaving it to the user to fill in .. and make other code changes. The suggestion would be Applicability::Unspecified. Let me know if you need more help with that.

Looks like the help caused this to happen again — any preferred tests I should remove this round?

I'm seeing if we can increase that that limit (Zulip thread). If not, please split the test into another file.

[camsteffen]

The stderr limit is removed! #7593

[shepmaster]

Ok, I added a commit with a potential suggestion implementation (I was thinking you wanted auto-fixable, which is why I was a bit 😰).

If you like it, I can squash the second and third commits.

[shepmaster]

All right, pushed up a new version. Let me know if you like it. If so, I'll squash the last two commits.

[camsteffen]

A couple more things, then go ahead and squash and I will merge.

[shepmaster]

Addressed!

[camsteffen]

Thanks! @bors r+

[bors]

📌 Commit b477543 has been approved by camsteffen

[bors]

⌛ Testing commit b477543 with merge 90e40f8...

[bors]

💔 Test failed - checks-action_test

[camsteffen]

@bors r+

[bors]

💡 This pull request was already approved, no need to approve it again.

• This pull request previously failed. You should add more commits to fix the bug, or use retry to trigger a build again.

[bors]

📌 Commit b477543 has been approved by camsteffen

[bors]

⌛ Testing commit b477543 with merge f771927...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: camsteffen
Pushing f771927 to master...