Add needless_character_iteration lint
#12815
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Fixed dogfood errors. |
| #![allow(clippy::unnecessary_operation)] | ||
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| fn main() { | ||
| "foo".chars().all(|c| c.is_ascii()); |
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Can you add a test where there is a different method between chars() and all()? Also some test where the all call tests something else as well, like .all(|c| c.is_ascii() && c.is_alphabetic())
| ExprKind::Block(block, _) => { | ||
| if let Some(block_expr) = block.expr | ||
| // First we ensure that this is a "binding chain" (each statement is a binding | ||
| // of the previous one) and that it is a binding of the closure argument. | ||
| && let Some(last_chain_binding_id) = | ||
| get_last_chain_binding_hir_id(first_param, block.stmts) | ||
| { | ||
| handle_expr(cx, block_expr, last_chain_binding_id, span, before_chars, revert); | ||
| } | ||
| }, |
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I feel like this part complicates the lint unnecessary. If people write weird code where they chain these things, I'd say it's okay to not lint it, but we can keep it if you want.
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It's convenient and easy enough to check so if you don't mind, I'd prefer to keep it. ;)
GuillaumeGomez
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Fixed the corner cases and added more tests. |
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Roses are red, |
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☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test |
| --> tests/ui/needless_character_iteration.rs:24:5 | ||
| | | ||
| LL | "foo".chars().all(|c| !char::is_ascii(&c)); | ||
| | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `!"foo".is_ascii()` |
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This transformation isn't correct:
fn main() {
let s = "Beyoncé";
// EVERY character isn't ascii
dbg!(s.chars().all(|c| !char::is_ascii(&c)));
// ANY character isn't ascii
dbg!(!s.is_ascii());
}[src/main.rs:3:5] s.chars().all(|c| !char::is_ascii(&c)) = false
[src/main.rs:4:5] !s.is_ascii() = true
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Great catch! Interested into send a fix? Otherwise please open an issue tagging me on it.
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I won't have time to work on this before it becomes a problem for nightly users. Filled #12879
Fixes #4817.
r? @xFrednet
changelog: Add
needless_character_iterationlint