diff options
| -rw-r--r-- | clippy_lints/src/loops/single_element_loop.rs | 35 | ||||
| -rw-r--r-- | tests/ui/single_element_loop.fixed | 12 | ||||
| -rw-r--r-- | tests/ui/single_element_loop.stderr | 72 |
3 files changed, 45 insertions, 74 deletions
diff --git a/clippy_lints/src/loops/single_element_loop.rs b/clippy_lints/src/loops/single_element_loop.rs index d860b297a02..4773a1454b7 100644 --- a/clippy_lints/src/loops/single_element_loop.rs +++ b/clippy_lints/src/loops/single_element_loop.rs @@ -1,6 +1,6 @@ use super::SINGLE_ELEMENT_LOOP; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::source::{indent_of, snippet_with_applicability}; +use clippy_utils::source::{indent_of, snippet, snippet_with_applicability}; use clippy_utils::visitors::contains_break_or_continue; use rustc_ast::util::parser::PREC_PREFIX; use rustc_ast::Mutability; @@ -87,14 +87,29 @@ pub(super) fn check<'tcx>( arg_snip = format!("({arg_snip})").into(); } - span_lint_and_sugg( - cx, - SINGLE_ELEMENT_LOOP, - expr.span, - "for loop over a single element", - "try", - format!("{{\n{indent}let {pat_snip} = {prefix}{arg_snip};{block_str}}}"), - applicability, - ); + if clippy_utils::higher::Range::hir(arg_expression).is_some() { + let range_expr = snippet(cx, arg_expression.span, "?").to_string(); + + let sugg = snippet(cx, arg_expression.span, ".."); + span_lint_and_sugg( + cx, + SINGLE_ELEMENT_LOOP, + arg.span, + format!("this loops only once with `{pat_snip}` being `{range_expr}`").as_str(), + "did you mean to iterate over the range instead?", + sugg.to_string(), + Applicability::Unspecified, + ); + } else { + span_lint_and_sugg( + cx, + SINGLE_ELEMENT_LOOP, + expr.span, + "for loop over a single element", + "try", + format!("{{\n{indent}let {pat_snip} = {prefix}{arg_snip};{block_str}}}"), + applicability, + ); + } } } diff --git a/tests/ui/single_element_loop.fixed b/tests/ui/single_element_loop.fixed index a82eb6afcf5..4e59c763198 100644 --- a/tests/ui/single_element_loop.fixed +++ b/tests/ui/single_element_loop.fixed @@ -15,23 +15,19 @@ fn main() { dbg!(item); } - { - let item = &(0..5); + for item in 0..5 { dbg!(item); } - { - let item = &mut (0..5); + for item in 0..5 { dbg!(item); } - { - let item = 0..5; + for item in 0..5 { dbg!(item); } - { - let item = 0..5; + for item in 0..5 { dbg!(item); } diff --git a/tests/ui/single_element_loop.stderr b/tests/ui/single_element_loop.stderr index 603dd7406e4..952d704143a 100644 --- a/tests/ui/single_element_loop.stderr +++ b/tests/ui/single_element_loop.stderr @@ -32,69 +32,29 @@ LL + dbg!(item); LL + } | -error: for loop over a single element - --> $DIR/single_element_loop.rs:16:5 - | -LL | / for item in &[0..5] { -LL | | dbg!(item); -LL | | } - | |_____^ - | -help: try - | -LL ~ { -LL + let item = &(0..5); -LL + dbg!(item); -LL + } +error: this loops only once with `item` being `0..5` + --> $DIR/single_element_loop.rs:16:17 | +LL | for item in &[0..5] { + | ^^^^^^^ help: did you mean to iterate over the range instead?: `0..5` -error: for loop over a single element - --> $DIR/single_element_loop.rs:20:5 - | -LL | / for item in [0..5].iter_mut() { -LL | | dbg!(item); -LL | | } - | |_____^ - | -help: try - | -LL ~ { -LL + let item = &mut (0..5); -LL + dbg!(item); -LL + } +error: this loops only once with `item` being `0..5` + --> $DIR/single_element_loop.rs:20:17 | +LL | for item in [0..5].iter_mut() { + | ^^^^^^^^^^^^^^^^^ help: did you mean to iterate over the range instead?: `0..5` -error: for loop over a single element - --> $DIR/single_element_loop.rs:24:5 - | -LL | / for item in [0..5] { -LL | | dbg!(item); -LL | | } - | |_____^ - | -help: try - | -LL ~ { -LL + let item = 0..5; -LL + dbg!(item); -LL + } +error: this loops only once with `item` being `0..5` + --> $DIR/single_element_loop.rs:24:17 | +LL | for item in [0..5] { + | ^^^^^^ help: did you mean to iterate over the range instead?: `0..5` -error: for loop over a single element - --> $DIR/single_element_loop.rs:28:5 - | -LL | / for item in [0..5].into_iter() { -LL | | dbg!(item); -LL | | } - | |_____^ - | -help: try - | -LL ~ { -LL + let item = 0..5; -LL + dbg!(item); -LL + } +error: this loops only once with `item` being `0..5` + --> $DIR/single_element_loop.rs:28:17 | +LL | for item in [0..5].into_iter() { + | ^^^^^^^^^^^^^^^^^^ help: did you mean to iterate over the range instead?: `0..5` error: for loop over a single element --> $DIR/single_element_loop.rs:47:5 |