diff options
| -rw-r--r-- | clippy_lints/src/manual_retain.rs | 141 | ||||
| -rw-r--r-- | tests/ui/manual_retain.fixed | 63 | ||||
| -rw-r--r-- | tests/ui/manual_retain.rs | 63 | ||||
| -rw-r--r-- | tests/ui/manual_retain.stderr | 142 |
4 files changed, 345 insertions, 64 deletions
diff --git a/clippy_lints/src/manual_retain.rs b/clippy_lints/src/manual_retain.rs index 1fe247dacb9..6f15fca089e 100644 --- a/clippy_lints/src/manual_retain.rs +++ b/clippy_lints/src/manual_retain.rs @@ -11,6 +11,7 @@ use rustc_lint::{LateContext, LateLintPass}; use rustc_semver::RustcVersion; use rustc_session::impl_lint_pass; use rustc_span::symbol::sym; +use rustc_span::Span; const ACCEPTABLE_METHODS: [&[&str]; 5] = [ &paths::BINARYHEAP_ITER, @@ -28,6 +29,7 @@ const ACCEPTABLE_TYPES: [(rustc_span::Symbol, Option<RustcVersion>); 7] = [ (sym::Vec, None), (sym::VecDeque, None), ]; +const MAP_TYPES: [rustc_span::Symbol; 2] = [sym::BTreeMap, sym::HashMap]; declare_clippy_lint! { /// ### What it does @@ -44,6 +46,7 @@ declare_clippy_lint! { /// ```no_run /// let mut vec = vec![0, 1, 2]; /// vec.retain(|x| x % 2 == 0); + /// vec.retain(|x| x % 2 == 0); /// ``` #[clippy::version = "1.64.0"] pub MANUAL_RETAIN, @@ -74,9 +77,9 @@ impl<'tcx> LateLintPass<'tcx> for ManualRetain { && let Some(collect_def_id) = cx.typeck_results().type_dependent_def_id(collect_expr.hir_id) && cx.tcx.is_diagnostic_item(sym::iterator_collect_fn, collect_def_id) { - check_into_iter(cx, parent_expr, left_expr, target_expr, &self.msrv); - check_iter(cx, parent_expr, left_expr, target_expr, &self.msrv); - check_to_owned(cx, parent_expr, left_expr, target_expr, &self.msrv); + check_into_iter(cx, left_expr, target_expr, parent_expr.span, &self.msrv); + check_iter(cx, left_expr, target_expr, parent_expr.span, &self.msrv); + check_to_owned(cx, left_expr, target_expr, parent_expr.span, &self.msrv); } } @@ -85,9 +88,9 @@ impl<'tcx> LateLintPass<'tcx> for ManualRetain { fn check_into_iter( cx: &LateContext<'_>, - parent_expr: &hir::Expr<'_>, left_expr: &hir::Expr<'_>, target_expr: &hir::Expr<'_>, + parent_expr_span: Span, msrv: &Msrv, ) { if let hir::ExprKind::MethodCall(_, into_iter_expr, [_], _) = &target_expr.kind @@ -98,16 +101,39 @@ fn check_into_iter( && Some(into_iter_def_id) == cx.tcx.lang_items().into_iter_fn() && match_acceptable_type(cx, left_expr, msrv) && SpanlessEq::new(cx).eq_expr(left_expr, struct_expr) + && let hir::ExprKind::MethodCall(_, _, [closure_expr], _) = target_expr.kind + && let hir::ExprKind::Closure(closure) = closure_expr.kind + && let filter_body = cx.tcx.hir().body(closure.body) + && let [filter_params] = filter_body.params { - suggest(cx, parent_expr, left_expr, target_expr); + if match_map_type(cx, left_expr) { + if let hir::PatKind::Tuple([key_pat, value_pat], _) = filter_params.pat.kind { + if let Some(sugg) = make_sugg(cx, key_pat, value_pat, left_expr, filter_body) { + make_span_lint_and_sugg(cx, parent_expr_span, sugg); + } + } + // Cannot lint other cases because `retain` requires two parameters + } else { + // Can always move because `retain` and `filter` have the same bound on the predicate + // for other types + make_span_lint_and_sugg( + cx, + parent_expr_span, + format!( + "{}.retain({})", + snippet(cx, left_expr.span, ".."), + snippet(cx, closure_expr.span, "..") + ), + ); + } } } fn check_iter( cx: &LateContext<'_>, - parent_expr: &hir::Expr<'_>, left_expr: &hir::Expr<'_>, target_expr: &hir::Expr<'_>, + parent_expr_span: Span, msrv: &Msrv, ) { if let hir::ExprKind::MethodCall(_, filter_expr, [], _) = &target_expr.kind @@ -122,16 +148,50 @@ fn check_iter( && match_acceptable_def_path(cx, iter_expr_def_id) && match_acceptable_type(cx, left_expr, msrv) && SpanlessEq::new(cx).eq_expr(left_expr, struct_expr) + && let hir::ExprKind::MethodCall(_, _, [closure_expr], _) = filter_expr.kind + && let hir::ExprKind::Closure(closure) = closure_expr.kind + && let filter_body = cx.tcx.hir().body(closure.body) + && let [filter_params] = filter_body.params { - suggest(cx, parent_expr, left_expr, filter_expr); + match filter_params.pat.kind { + // hir::PatKind::Binding(_, _, _, None) => { + // // Be conservative now. Do nothing here. + // // TODO: Ideally, we can rewrite the lambda by stripping one level of reference + // }, + hir::PatKind::Tuple([_, _], _) => { + // the `&&` reference for the `filter` method will be auto derefed to `ref` + // so, we can directly use the lambda + // https://doc.rust-lang.org/reference/patterns.html#binding-modes + make_span_lint_and_sugg( + cx, + parent_expr_span, + format!( + "{}.retain({})", + snippet(cx, left_expr.span, ".."), + snippet(cx, closure_expr.span, "..") + ), + ); + }, + hir::PatKind::Ref(pat, _) => make_span_lint_and_sugg( + cx, + parent_expr_span, + format!( + "{}.retain(|{}| {})", + snippet(cx, left_expr.span, ".."), + snippet(cx, pat.span, ".."), + snippet(cx, filter_body.value.span, "..") + ), + ), + _ => {}, + } } } fn check_to_owned( cx: &LateContext<'_>, - parent_expr: &hir::Expr<'_>, left_expr: &hir::Expr<'_>, target_expr: &hir::Expr<'_>, + parent_expr_span: Span, msrv: &Msrv, ) { if msrv.meets(msrvs::STRING_RETAIN) @@ -147,43 +207,25 @@ fn check_to_owned( && let ty = cx.typeck_results().expr_ty(str_expr).peel_refs() && is_type_lang_item(cx, ty, hir::LangItem::String) && SpanlessEq::new(cx).eq_expr(left_expr, str_expr) - { - suggest(cx, parent_expr, left_expr, filter_expr); - } -} - -fn suggest(cx: &LateContext<'_>, parent_expr: &hir::Expr<'_>, left_expr: &hir::Expr<'_>, filter_expr: &hir::Expr<'_>) { - if let hir::ExprKind::MethodCall(_, _, [closure], _) = filter_expr.kind - && let hir::ExprKind::Closure(&hir::Closure { body, .. }) = closure.kind - && let filter_body = cx.tcx.hir().body(body) + && let hir::ExprKind::MethodCall(_, _, [closure_expr], _) = filter_expr.kind + && let hir::ExprKind::Closure(closure) = closure_expr.kind + && let filter_body = cx.tcx.hir().body(closure.body) && let [filter_params] = filter_body.params - && let Some(sugg) = match filter_params.pat.kind { - hir::PatKind::Binding(_, _, filter_param_ident, None) => Some(format!( - "{}.retain(|{filter_param_ident}| {})", - snippet(cx, left_expr.span, ".."), - snippet(cx, filter_body.value.span, "..") - )), - hir::PatKind::Tuple([key_pat, value_pat], _) => make_sugg(cx, key_pat, value_pat, left_expr, filter_body), - hir::PatKind::Ref(pat, _) => match pat.kind { - hir::PatKind::Binding(_, _, filter_param_ident, None) => Some(format!( - "{}.retain(|{filter_param_ident}| {})", + { + if let hir::PatKind::Ref(pat, _) = filter_params.pat.kind { + make_span_lint_and_sugg( + cx, + parent_expr_span, + format!( + "{}.retain(|{}| {})", snippet(cx, left_expr.span, ".."), + snippet(cx, pat.span, ".."), snippet(cx, filter_body.value.span, "..") - )), - _ => None, - }, - _ => None, + ), + ); } - { - span_lint_and_sugg( - cx, - MANUAL_RETAIN, - parent_expr.span, - "this expression can be written more simply using `.retain()`", - "consider calling `.retain()` instead", - sugg, - Applicability::MachineApplicable, - ); + // Be conservative now. Do nothing for the `Binding` case. + // TODO: Ideally, we can rewrite the lambda by stripping one level of reference } } @@ -229,3 +271,20 @@ fn match_acceptable_type(cx: &LateContext<'_>, expr: &hir::Expr<'_>, msrv: &Msrv && acceptable_msrv.map_or(true, |acceptable_msrv| msrv.meets(acceptable_msrv)) }) } + +fn match_map_type(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> bool { + let expr_ty = cx.typeck_results().expr_ty(expr).peel_refs(); + MAP_TYPES.iter().any(|ty| is_type_diagnostic_item(cx, expr_ty, *ty)) +} + +fn make_span_lint_and_sugg(cx: &LateContext<'_>, span: Span, sugg: String) { + span_lint_and_sugg( + cx, + MANUAL_RETAIN, + span, + "this expression can be written more simply using `.retain()`", + "consider calling `.retain()` instead", + sugg, + Applicability::MachineApplicable, + ); +} diff --git a/tests/ui/manual_retain.fixed b/tests/ui/manual_retain.fixed index 4dea3e8bfe6..5540029bf6b 100644 --- a/tests/ui/manual_retain.fixed +++ b/tests/ui/manual_retain.fixed @@ -14,6 +14,9 @@ fn main() { _msrv_153(); _msrv_126(); _msrv_118(); + + issue_10393(); + issue_12081(); } fn binary_heap_retain() { @@ -23,6 +26,11 @@ fn binary_heap_retain() { binary_heap.retain(|x| x % 2 == 0); binary_heap.retain(|x| x % 2 == 0); + // Do lint, because we use pattern matching + let mut tuples = BinaryHeap::from([(0, 1), (1, 2), (2, 3)]); + tuples.retain(|(ref x, ref y)| *x == 0); + tuples.retain(|(x, y)| *x == 0); + // Do not lint, because type conversion is performed binary_heap = binary_heap .into_iter() @@ -55,6 +63,9 @@ fn btree_map_retain() { btree_map.retain(|_, &mut v| v % 2 == 0); btree_map.retain(|k, &mut v| (k % 2 == 0) && (v % 2 == 0)); + // Do not lint, because the parameters are not matched in tuple pattern + btree_map = btree_map.into_iter().filter(|t| t.0 % 2 == 0).collect(); + // Do not lint. btree_map = btree_map .into_iter() @@ -76,6 +87,11 @@ fn btree_set_retain() { btree_set.retain(|x| x % 2 == 0); btree_set.retain(|x| x % 2 == 0); + // Do lint, because we use pattern matching + let mut tuples = BTreeSet::from([(0, 1), (1, 2), (2, 3)]); + tuples.retain(|(ref x, ref y)| *x == 0); + tuples.retain(|(x, y)| *x == 0); + // Do not lint, because type conversion is performed btree_set = btree_set .iter() @@ -108,6 +124,9 @@ fn hash_map_retain() { hash_map.retain(|_, &mut v| v % 2 == 0); hash_map.retain(|k, &mut v| (k % 2 == 0) && (v % 2 == 0)); + // Do not lint, because the parameters are not matched in tuple pattern + hash_map = hash_map.into_iter().filter(|t| t.0 % 2 == 0).collect(); + // Do not lint. hash_map = hash_map .into_iter() @@ -128,6 +147,11 @@ fn hash_set_retain() { hash_set.retain(|x| x % 2 == 0); hash_set.retain(|x| x % 2 == 0); + // Do lint, because we use pattern matching + let mut tuples = HashSet::from([(0, 1), (1, 2), (2, 3)]); + tuples.retain(|(ref x, ref y)| *x == 0); + tuples.retain(|(x, y)| *x == 0); + // Do not lint, because type conversion is performed hash_set = hash_set.into_iter().filter(|x| x % 2 == 0).collect::<HashSet<i8>>(); hash_set = hash_set @@ -171,6 +195,11 @@ fn vec_retain() { vec.retain(|x| x % 2 == 0); vec.retain(|x| x % 2 == 0); + // Do lint, because we use pattern matching + let mut tuples = vec![(0, 1), (1, 2), (2, 3)]; + tuples.retain(|(ref x, ref y)| *x == 0); + tuples.retain(|(x, y)| *x == 0); + // Do not lint, because type conversion is performed vec = vec.into_iter().filter(|x| x % 2 == 0).collect::<Vec<i8>>(); vec = vec.iter().filter(|&x| x % 2 == 0).copied().collect::<Vec<i8>>(); @@ -246,3 +275,37 @@ fn _msrv_118() { let mut hash_map: HashMap<i8, i8> = (0..8).map(|x| (x, x * 10)).collect(); hash_map = hash_map.into_iter().filter(|(k, _)| k % 2 == 0).collect(); } + +fn issue_10393() { + // Do lint + let mut vec = vec![(0, 1), (1, 2), (2, 3)]; + vec.retain(|(x, y)| *x == 0); + + // Do lint + let mut tuples = vec![(true, -2), (false, 3)]; + tuples.retain(|(_, n)| *n > 0); +} + +fn issue_11457() { + // Do not lint, as we need to modify the closure + let mut vals = vec![1, 2, 3, 4]; + vals = vals.iter().filter(|v| **v != 1).cloned().collect(); + + // Do not lint, as we need to modify the closure + let mut s = String::from("foobar"); + s = s.chars().filter(|c| *c != 'o').to_owned().collect(); +} + +fn issue_12081() { + let mut vec = vec![0, 1, 2]; + + // Do lint + vec.retain(|&x| x == 0); + vec.retain(|&x| x == 0); + vec.retain(|&x| x == 0); + + // Do lint + vec.retain(|x| *x == 0); + vec.retain(|x| *x == 0); + vec.retain(|x| *x == 0); +} diff --git a/tests/ui/manual_retain.rs b/tests/ui/manual_retain.rs index d839550f33a..cee641d9d65 100644 --- a/tests/ui/manual_retain.rs +++ b/tests/ui/manual_retain.rs @@ -14,6 +14,9 @@ fn main() { _msrv_153(); _msrv_126(); _msrv_118(); + + issue_10393(); + issue_12081(); } fn binary_heap_retain() { @@ -23,6 +26,11 @@ fn binary_heap_retain() { binary_heap = binary_heap.iter().filter(|&x| x % 2 == 0).copied().collect(); binary_heap = binary_heap.iter().filter(|&x| x % 2 == 0).cloned().collect(); + // Do lint, because we use pattern matching + let mut tuples = BinaryHeap::from([(0, 1), (1, 2), (2, 3)]); + tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + // Do not lint, because type conversion is performed binary_heap = binary_heap .into_iter() @@ -58,6 +66,9 @@ fn btree_map_retain() { .filter(|(k, v)| (k % 2 == 0) && (v % 2 == 0)) .collect(); + // Do not lint, because the parameters are not matched in tuple pattern + btree_map = btree_map.into_iter().filter(|t| t.0 % 2 == 0).collect(); + // Do not lint. btree_map = btree_map .into_iter() @@ -79,6 +90,11 @@ fn btree_set_retain() { btree_set = btree_set.iter().filter(|&x| x % 2 == 0).cloned().collect(); btree_set = btree_set.into_iter().filter(|x| x % 2 == 0).collect(); + // Do lint, because we use pattern matching + let mut tuples = BTreeSet::from([(0, 1), (1, 2), (2, 3)]); + tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + // Do not lint, because type conversion is performed btree_set = btree_set .iter() @@ -114,6 +130,9 @@ fn hash_map_retain() { .filter(|(k, v)| (k % 2 == 0) && (v % 2 == 0)) .collect(); + // Do not lint, because the parameters are not matched in tuple pattern + hash_map = hash_map.into_iter().filter(|t| t.0 % 2 == 0).collect(); + // Do not lint. hash_map = hash_map .into_iter() @@ -134,6 +153,11 @@ fn hash_set_retain() { hash_set = hash_set.iter().filter(|&x| x % 2 == 0).copied().collect(); hash_set = hash_set.iter().filter(|&x| x % 2 == 0).cloned().collect(); + // Do lint, because we use pattern matching + let mut tuples = HashSet::from([(0, 1), (1, 2), (2, 3)]); + tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + // Do not lint, because type conversion is performed hash_set = hash_set.into_iter().filter(|x| x % 2 == 0).collect::<HashSet<i8>>(); hash_set = hash_set @@ -177,6 +201,11 @@ fn vec_retain() { vec = vec.iter().filter(|&x| x % 2 == 0).cloned().collect(); vec = vec.into_iter().filter(|x| x % 2 == 0).collect(); + // Do lint, because we use pattern matching + let mut tuples = vec![(0, 1), (1, 2), (2, 3)]; + tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + // Do not lint, because type conversion is performed vec = vec.into_iter().filter(|x| x % 2 == 0).collect::<Vec<i8>>(); vec = vec.iter().filter(|&x| x % 2 == 0).copied().collect::<Vec<i8>>(); @@ -252,3 +281,37 @@ fn _msrv_118() { let mut hash_map: HashMap<i8, i8> = (0..8).map(|x| (x, x * 10)).collect(); hash_map = hash_map.into_iter().filter(|(k, _)| k % 2 == 0).collect(); } + +fn issue_10393() { + // Do lint + let mut vec = vec![(0, 1), (1, 2), (2, 3)]; + vec = vec.into_iter().filter(|(x, y)| *x == 0).collect(); + + // Do lint + let mut tuples = vec![(true, -2), (false, 3)]; + tuples = tuples.into_iter().filter(|(_, n)| *n > 0).collect(); +} + +fn issue_11457() { + // Do not lint, as we need to modify the closure + let mut vals = vec![1, 2, 3, 4]; + vals = vals.iter().filter(|v| **v != 1).cloned().collect(); + + // Do not lint, as we need to modify the closure + let mut s = String::from("foobar"); + s = s.chars().filter(|c| *c != 'o').to_owned().collect(); +} + +fn issue_12081() { + let mut vec = vec![0, 1, 2]; + + // Do lint + vec = vec.iter().filter(|&&x| x == 0).copied().collect(); + vec = vec.iter().filter(|&&x| x == 0).cloned().collect(); + vec = vec.into_iter().filter(|&x| x == 0).collect(); + + // Do lint + vec = vec.iter().filter(|&x| *x == 0).copied().collect(); + vec = vec.iter().filter(|&x| *x == 0).cloned().collect(); + vec = vec.into_iter().filter(|x| *x == 0).collect(); +} diff --git a/tests/ui/manual_retain.stderr b/tests/ui/manual_retain.stderr index 0c5b1383b6a..2c872f3b430 100644 --- a/tests/ui/manual_retain.stderr +++ b/tests/ui/manual_retain.stderr @@ -1,5 +1,5 @@ error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:22:5 + --> $DIR/manual_retain.rs:25:5 | LL | binary_heap = binary_heap.into_iter().filter(|x| x % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `binary_heap.retain(|x| x % 2 == 0)` @@ -8,31 +8,43 @@ LL | binary_heap = binary_heap.into_iter().filter(|x| x % 2 == 0).collect(); = help: to override `-D warnings` add `#[allow(clippy::manual_retain)]` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:23:5 + --> $DIR/manual_retain.rs:26:5 | LL | binary_heap = binary_heap.iter().filter(|&x| x % 2 == 0).copied().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `binary_heap.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:24:5 + --> $DIR/manual_retain.rs:27:5 | LL | binary_heap = binary_heap.iter().filter(|&x| x % 2 == 0).cloned().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `binary_heap.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:54:5 + --> $DIR/manual_retain.rs:31:5 + | +LL | tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(ref x, ref y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:32:5 + | +LL | tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(x, y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:62:5 | LL | btree_map = btree_map.into_iter().filter(|(k, _)| k % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `btree_map.retain(|k, _| k % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:55:5 + --> $DIR/manual_retain.rs:63:5 | LL | btree_map = btree_map.into_iter().filter(|(_, v)| v % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `btree_map.retain(|_, &mut v| v % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:56:5 + --> $DIR/manual_retain.rs:64:5 | LL | / btree_map = btree_map LL | | .into_iter() @@ -41,37 +53,49 @@ LL | | .collect(); | |__________________^ help: consider calling `.retain()` instead: `btree_map.retain(|k, &mut v| (k % 2 == 0) && (v % 2 == 0))` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:78:5 + --> $DIR/manual_retain.rs:89:5 | LL | btree_set = btree_set.iter().filter(|&x| x % 2 == 0).copied().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `btree_set.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:79:5 + --> $DIR/manual_retain.rs:90:5 | LL | btree_set = btree_set.iter().filter(|&x| x % 2 == 0).cloned().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `btree_set.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:80:5 + --> $DIR/manual_retain.rs:91:5 | LL | btree_set = btree_set.into_iter().filter(|x| x % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `btree_set.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:110:5 + --> $DIR/manual_retain.rs:95:5 + | +LL | tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(ref x, ref y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:96:5 + | +LL | tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(x, y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:126:5 | LL | hash_map = hash_map.into_iter().filter(|(k, _)| k % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `hash_map.retain(|k, _| k % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:111:5 + --> $DIR/manual_retain.rs:127:5 | LL | hash_map = hash_map.into_iter().filter(|(_, v)| v % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `hash_map.retain(|_, &mut v| v % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:112:5 + --> $DIR/manual_retain.rs:128:5 | LL | / hash_map = hash_map LL | | .into_iter() @@ -80,64 +104,136 @@ LL | | .collect(); | |__________________^ help: consider calling `.retain()` instead: `hash_map.retain(|k, &mut v| (k % 2 == 0) && (v % 2 == 0))` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:133:5 + --> $DIR/manual_retain.rs:152:5 | LL | hash_set = hash_set.into_iter().filter(|x| x % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `hash_set.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:134:5 + --> $DIR/manual_retain.rs:153:5 | LL | hash_set = hash_set.iter().filter(|&x| x % 2 == 0).copied().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `hash_set.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:135:5 + --> $DIR/manual_retain.rs:154:5 | LL | hash_set = hash_set.iter().filter(|&x| x % 2 == 0).cloned().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `hash_set.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:164:5 + --> $DIR/manual_retain.rs:158:5 + | +LL | tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(ref x, ref y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:159:5 + | +LL | tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(x, y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:188:5 | LL | s = s.chars().filter(|&c| c != 'o').to_owned().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `s.retain(|c| c != 'o')` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:176:5 + --> $DIR/manual_retain.rs:200:5 | LL | vec = vec.iter().filter(|&x| x % 2 == 0).copied().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:177:5 + --> $DIR/manual_retain.rs:201:5 | LL | vec = vec.iter().filter(|&x| x % 2 == 0).cloned().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:178:5 + --> $DIR/manual_retain.rs:202:5 | LL | vec = vec.into_iter().filter(|x| x % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:200:5 + --> $DIR/manual_retain.rs:206:5 + | +LL | tuples = tuples.iter().filter(|(ref x, ref y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(ref x, ref y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:207:5 + | +LL | tuples = tuples.iter().filter(|(x, y)| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(x, y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:229:5 | LL | vec_deque = vec_deque.iter().filter(|&x| x % 2 == 0).copied().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec_deque.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:201:5 + --> $DIR/manual_retain.rs:230:5 | LL | vec_deque = vec_deque.iter().filter(|&x| x % 2 == 0).cloned().collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec_deque.retain(|x| x % 2 == 0)` error: this expression can be written more simply using `.retain()` - --> $DIR/manual_retain.rs:202:5 + --> $DIR/manual_retain.rs:231:5 | LL | vec_deque = vec_deque.into_iter().filter(|x| x % 2 == 0).collect(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec_deque.retain(|x| x % 2 == 0)` -error: aborting due to 22 previous errors +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:288:5 + | +LL | vec = vec.into_iter().filter(|(x, y)| *x == 0).collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|(x, y)| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:292:5 + | +LL | tuples = tuples.into_iter().filter(|(_, n)| *n > 0).collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `tuples.retain(|(_, n)| *n > 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:309:5 + | +LL | vec = vec.iter().filter(|&&x| x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|&x| x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:310:5 + | +LL | vec = vec.iter().filter(|&&x| x == 0).cloned().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|&x| x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:311:5 + | +LL | vec = vec.into_iter().filter(|&x| x == 0).collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|&x| x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:314:5 + | +LL | vec = vec.iter().filter(|&x| *x == 0).copied().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|x| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:315:5 + | +LL | vec = vec.iter().filter(|&x| *x == 0).cloned().collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|x| *x == 0)` + +error: this expression can be written more simply using `.retain()` + --> $DIR/manual_retain.rs:316:5 + | +LL | vec = vec.into_iter().filter(|x| *x == 0).collect(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling `.retain()` instead: `vec.retain(|x| *x == 0)` + +error: aborting due to 38 previous errors |