[single_component_path_imports] to include super:: and crate::; …

[mautamu]

Howdy,

This is my attempt to fix #7168.

I added a tracker variable to [single_component_path_imports] for what I'm referring to as "root paths," i.e. crate::* and super::*. With this, we add another check to filter out those prior to emitting warnings.

Let me know what could be done better!

Best,
Mautamu

r? @djc @camsteffen
fixes: #7168
changelog: Don't trigger [single_component_path_imports] on an import if crate::import or super::import are invoked.

[camsteffen]

r? @camsteffen

[camsteffen]

Thanks for contributing to clippy!

We should make sure we don't introduce false negatives where super refers to something at a different level. If I'm not mistaken, we need a more robust solution to detect theses cases (and we should have tests for some negative cases).

use x; // this should lint

mod a {
    use x; // this should not lint
	mod b {
	      fn f() {
	          super::x::..;
	      }
	}
}

Also I'm concerned about performance with collecting uses for the entire crate in a Vec and then using Vec::contains.

This is a little difficult for a first-time contribution, but you are certainly welcome to stick to it!

Here is one idea.

1. Add imports: Vec<FxHashMap<Symbol, Span>> to SingleComponentPathImports
2. When you visit use x, add it to imports.last()
3. When you visit a nested mod (in check_item if ItemKind::Mod) push a new set onto imports
4. When you visit super::x::.. remove x from imports[imports.len() - number_of_supers - 1]
5. At the end of a module (check_item_post), imports.pop() and lint every element in the set.

Perhaps all of the Vecs currently being used could be removed and just use imports. But not required.

[bors]

☔ The latest upstream changes (presumably #7254) made this pull request unmergeable. Please resolve the merge conflicts.

[giraffate]

ping from triage @mautamu. Can you have any updates on this? If you have any questions, feel free to ask us!

[mautamu]

ping from triage @mautamu. Can you have any updates on this? If you have any questions, feel free to ask us!

Oh thanks for checking back! Sorry about the delay, I’ll see what I can get done tomorrow.

[giraffate]

ping from triage @mautamu. Can you have any updates on this?

[giraffate]

ping from triage @mautamu. According to the triage procedure, I'm closing this because 2 weeks have passed with no activity. If you have more time to work on this, feel free to reopen this.