diff options
Diffstat (limited to 'clippy_lints/src/methods')
20 files changed, 477 insertions, 259 deletions
diff --git a/clippy_lints/src/methods/cloned_instead_of_copied.rs b/clippy_lints/src/methods/cloned_instead_of_copied.rs index 4e6ec61f6a8..fcafa162236 100644 --- a/clippy_lints/src/methods/cloned_instead_of_copied.rs +++ b/clippy_lints/src/methods/cloned_instead_of_copied.rs @@ -1,6 +1,6 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::is_trait_method; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::ty::{get_iterator_item_ty, is_copy}; use rustc_errors::Applicability; use rustc_hir::Expr; diff --git a/clippy_lints/src/methods/err_expect.rs b/clippy_lints/src/methods/err_expect.rs index 3d82441c0e6..a8d4dd5e4f3 100644 --- a/clippy_lints/src/methods/err_expect.rs +++ b/clippy_lints/src/methods/err_expect.rs @@ -1,6 +1,6 @@ use super::ERR_EXPECT; +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::ty::{has_debug_impl, is_type_diagnostic_item}; use rustc_errors::Applicability; use rustc_lint::LateContext; diff --git a/clippy_lints/src/methods/filter_map_next.rs b/clippy_lints/src/methods/filter_map_next.rs index 3f89e593148..f94fe221833 100644 --- a/clippy_lints/src/methods/filter_map_next.rs +++ b/clippy_lints/src/methods/filter_map_next.rs @@ -1,6 +1,6 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg}; use clippy_utils::is_trait_method; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet; use rustc_errors::Applicability; use rustc_hir as hir; diff --git a/clippy_lints/src/methods/get_first.rs b/clippy_lints/src/methods/get_first.rs index e7b4564c651..2e1dd3ec649 100644 --- a/clippy_lints/src/methods/get_first.rs +++ b/clippy_lints/src/methods/get_first.rs @@ -1,11 +1,13 @@ use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::source::snippet_with_applicability; +use clippy_utils::ty::is_type_diagnostic_item; use if_chain::if_chain; use rustc_ast::LitKind; use rustc_errors::Applicability; use rustc_hir as hir; use rustc_lint::LateContext; use rustc_span::source_map::Spanned; +use rustc_span::sym; use super::GET_FIRST; @@ -18,20 +20,34 @@ pub(super) fn check<'tcx>( if_chain! { if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id); if let Some(impl_id) = cx.tcx.impl_of_method(method_id); - if cx.tcx.type_of(impl_id).instantiate_identity().is_slice(); + let identity = cx.tcx.type_of(impl_id).instantiate_identity(); if let hir::ExprKind::Lit(Spanned { node: LitKind::Int(0, _), .. }) = arg.kind; then { - let mut app = Applicability::MachineApplicable; - let slice_name = snippet_with_applicability(cx, recv.span, "..", &mut app); - span_lint_and_sugg( - cx, - GET_FIRST, - expr.span, - &format!("accessing first element with `{slice_name}.get(0)`"), - "try", - format!("{slice_name}.first()"), - app, - ); + if identity.is_slice() { + let mut app = Applicability::MachineApplicable; + let slice_name = snippet_with_applicability(cx, recv.span, "..", &mut app); + span_lint_and_sugg( + cx, + GET_FIRST, + expr.span, + &format!("accessing first element with `{slice_name}.get(0)`"), + "try", + format!("{slice_name}.first()"), + app, + ); + } else if is_type_diagnostic_item(cx, identity, sym::VecDeque){ + let mut app = Applicability::MachineApplicable; + let slice_name = snippet_with_applicability(cx, recv.span, "..", &mut app); + span_lint_and_sugg( + cx, + GET_FIRST, + expr.span, + &format!("accessing first element with `{slice_name}.get(0)`"), + "try", + format!("{slice_name}.front()"), + app, + ); + } } } } diff --git a/clippy_lints/src/methods/is_digit_ascii_radix.rs b/clippy_lints/src/methods/is_digit_ascii_radix.rs index 120f3d5f42c..e963950960a 100644 --- a/clippy_lints/src/methods/is_digit_ascii_radix.rs +++ b/clippy_lints/src/methods/is_digit_ascii_radix.rs @@ -1,9 +1,9 @@ //! Lint for `c.is_digit(10)` use super::IS_DIGIT_ASCII_RADIX; +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::consts::{constant_full_int, FullInt}; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet_with_applicability; use rustc_errors::Applicability; use rustc_hir::Expr; diff --git a/clippy_lints/src/methods/iter_kv_map.rs b/clippy_lints/src/methods/iter_kv_map.rs index b44a2716dde..625325d4cf5 100644 --- a/clippy_lints/src/methods/iter_kv_map.rs +++ b/clippy_lints/src/methods/iter_kv_map.rs @@ -3,9 +3,8 @@ use super::ITER_KV_MAP; use clippy_utils::diagnostics::{multispan_sugg, span_lint_and_sugg, span_lint_and_then}; use clippy_utils::source::{snippet, snippet_with_applicability}; -use clippy_utils::sugg; use clippy_utils::ty::is_type_diagnostic_item; -use clippy_utils::visitors::is_local_used; +use clippy_utils::{pat_is_wild, sugg}; use rustc_hir::{BindingAnnotation, Body, BorrowKind, ByRef, Expr, ExprKind, Mutability, Pat, PatKind}; use rustc_lint::{LateContext, LintContext}; use rustc_middle::ty; @@ -84,13 +83,3 @@ pub(super) fn check<'tcx>( } } } - -/// Returns `true` if the pattern is a `PatWild`, or is an ident prefixed with `_` -/// that is not locally used. -fn pat_is_wild<'tcx>(cx: &LateContext<'tcx>, pat: &'tcx PatKind<'_>, body: &'tcx Expr<'_>) -> bool { - match *pat { - PatKind::Wild => true, - PatKind::Binding(_, id, ident, None) if ident.as_str().starts_with('_') => !is_local_used(cx, body, id), - _ => false, - } -} diff --git a/clippy_lints/src/methods/manual_try_fold.rs b/clippy_lints/src/methods/manual_try_fold.rs index dabed0affcf..5fc968f793f 100644 --- a/clippy_lints/src/methods/manual_try_fold.rs +++ b/clippy_lints/src/methods/manual_try_fold.rs @@ -1,6 +1,6 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::is_from_proc_macro; -use clippy_utils::msrvs::{Msrv, ITERATOR_TRY_FOLD}; use clippy_utils::source::snippet_opt; use clippy_utils::ty::implements_trait; use rustc_errors::Applicability; @@ -21,7 +21,7 @@ pub(super) fn check<'tcx>( msrv: &Msrv, ) { if !in_external_macro(cx.sess(), fold_span) - && msrv.meets(ITERATOR_TRY_FOLD) + && msrv.meets(msrvs::ITERATOR_TRY_FOLD) && let init_ty = cx.typeck_results().expr_ty(init) && let Some(try_trait) = cx.tcx.lang_items().try_trait() && implements_trait(cx, init_ty, try_trait, &[]) diff --git a/clippy_lints/src/methods/map_clone.rs b/clippy_lints/src/methods/map_clone.rs index 880efe60c1a..e0f8cb1b955 100644 --- a/clippy_lints/src/methods/map_clone.rs +++ b/clippy_lints/src/methods/map_clone.rs @@ -1,5 +1,5 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet_with_applicability; use clippy_utils::ty::{is_copy, is_type_diagnostic_item}; use clippy_utils::{is_diag_trait_item, peel_blocks}; diff --git a/clippy_lints/src/methods/map_unwrap_or.rs b/clippy_lints/src/methods/map_unwrap_or.rs index e70a1bc9879..cb81b3919bf 100644 --- a/clippy_lints/src/methods/map_unwrap_or.rs +++ b/clippy_lints/src/methods/map_unwrap_or.rs @@ -1,5 +1,5 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg}; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet; use clippy_utils::ty::is_type_diagnostic_item; use clippy_utils::usage::mutated_variables; diff --git a/clippy_lints/src/methods/mod.rs b/clippy_lints/src/methods/mod.rs index a935aea5075..90f6bc5e3d3 100644 --- a/clippy_lints/src/methods/mod.rs +++ b/clippy_lints/src/methods/mod.rs @@ -99,6 +99,7 @@ mod suspicious_to_owned; mod type_id_on_box; mod uninit_assumed_init; mod unit_hash; +mod unnecessary_fallible_conversions; mod unnecessary_filter_map; mod unnecessary_fold; mod unnecessary_iter_cloned; @@ -112,13 +113,14 @@ mod useless_asref; mod utils; mod vec_resize_to_zero; mod verbose_file_reads; +mod waker_clone_wake; mod wrong_self_convention; mod zst_offset; use bind_instead_of_map::BindInsteadOfMap; +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::consts::{constant, Constant}; use clippy_utils::diagnostics::{span_lint, span_lint_and_help}; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::ty::{contains_ty_adt_constructor_opaque, implements_trait, is_copy, is_type_diagnostic_item}; use clippy_utils::{contains_return, is_bool, is_trait_method, iter_input_pats, peel_blocks, return_ty}; use if_chain::if_chain; @@ -142,11 +144,11 @@ declare_clippy_lint! { /// implements `Copy`. /// /// ### Example - /// ```rust + /// ```no_run /// [1, 2, 3].iter().cloned(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// [1, 2, 3].iter().copied(); /// ``` #[clippy::version = "1.53.0"] @@ -165,14 +167,14 @@ declare_clippy_lint! { /// with repetitive code. /// /// ### Example - /// ```rust + /// ```no_run /// let hello = "hesuo worpd" /// .replace('s', "l") /// .replace("u", "l") /// .replace('p', "l"); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let hello = "hesuo worpd".replace(['s', 'u', 'p'], "l"); /// ``` #[clippy::version = "1.65.0"] @@ -194,14 +196,14 @@ declare_clippy_lint! { /// A code that relies on that side-effect could fail. /// /// ### Examples - /// ```rust + /// ```no_run /// # let vec = vec!["string".to_string()]; /// vec.iter().cloned().take(10); /// vec.iter().cloned().last(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let vec = vec!["string".to_string()]; /// vec.iter().take(10).cloned(); /// vec.iter().last().cloned(); @@ -222,11 +224,11 @@ declare_clippy_lint! { /// `Option` is used to produce 0 or 1 items. /// /// ### Example - /// ```rust + /// ```no_run /// let nums: Vec<i32> = ["1", "2", "whee!"].iter().flat_map(|x| x.parse().ok()).collect(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let nums: Vec<i32> = ["1", "2", "whee!"].iter().filter_map(|x| x.parse().ok()).collect(); /// ``` #[clippy::version = "1.53.0"] @@ -254,7 +256,7 @@ declare_clippy_lint! { /// where they may get displayed. Activate this lint to do just that. /// /// ### Examples - /// ```rust + /// ```no_run /// # let option = Some(1); /// # let result: Result<usize, ()> = Ok(1); /// option.unwrap(); @@ -262,7 +264,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let option = Some(1); /// # let result: Result<usize, ()> = Ok(1); /// option.expect("more helpful message"); @@ -293,14 +295,14 @@ declare_clippy_lint! { /// It is better to write the value directly without the indirection. /// /// ### Examples - /// ```rust + /// ```no_run /// let val1 = Some(1).unwrap(); /// let val2 = Ok::<_, ()>(1).unwrap(); /// let val3 = Err::<(), _>(1).unwrap_err(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let val1 = 1; /// let val2 = 1; /// let val3 = 1; @@ -363,7 +365,7 @@ declare_clippy_lint! { /// them. /// /// ### Example - /// ```rust + /// ```no_run /// struct X; /// impl X { /// fn add(&self, other: &X) -> X { @@ -412,7 +414,7 @@ declare_clippy_lint! { /// mutable reference to a `as_..` function. /// /// ### Example - /// ```rust + /// ```no_run /// # struct X; /// impl X { /// fn as_str(self) -> &'static str { @@ -439,13 +441,13 @@ declare_clippy_lint! { /// The error type needs to implement `Debug` /// /// ### Example - /// ```rust + /// ```no_run /// # let x = Ok::<_, ()>(()); /// x.ok().expect("why did I do this again?"); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let x = Ok::<_, ()>(()); /// x.expect("why did I do this again?"); /// ``` @@ -496,7 +498,7 @@ declare_clippy_lint! { /// heuristic to try to identify such cases. However, the heuristic can produce false negatives. /// /// ### Examples - /// ```rust + /// ```no_run /// # let x = Some(1); /// # let mut map = std::collections::HashMap::<u64, String>::new(); /// x.unwrap_or(Default::default()); @@ -504,7 +506,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let x = Some(1); /// # let mut map = std::collections::HashMap::<u64, String>::new(); /// x.unwrap_or_default(); @@ -529,7 +531,7 @@ declare_clippy_lint! { /// The order of the arguments is not in execution order /// /// ### Examples - /// ```rust + /// ```no_run /// # let option = Some(1); /// # let result: Result<usize, ()> = Ok(1); /// # fn some_function(foo: ()) -> usize { 1 } @@ -539,7 +541,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let option = Some(1); /// # let result: Result<usize, ()> = Ok(1); /// # fn some_function(foo: ()) -> usize { 1 } @@ -565,13 +567,13 @@ declare_clippy_lint! { /// The order of the arguments is not in execution order. /// /// ### Example - /// ```rust + /// ```no_run /// # let opt = Some(1); /// opt.map_or(None, |a| Some(a + 1)); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let opt = Some(1); /// opt.and_then(|a| Some(a + 1)); /// ``` @@ -590,13 +592,13 @@ declare_clippy_lint! { /// `_.ok()`. /// /// ### Example - /// ```rust + /// ```no_run /// # let r: Result<u32, &str> = Ok(1); /// assert_eq!(Some(1), r.map_or(None, Some)); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let r: Result<u32, &str> = Ok(1); /// assert_eq!(Some(1), r.ok()); /// ``` @@ -616,7 +618,7 @@ declare_clippy_lint! { /// `_.map(|x| y)` or `_.map_err(|x| y)`. /// /// ### Example - /// ```rust + /// ```no_run /// # fn opt() -> Option<&'static str> { Some("42") } /// # fn res() -> Result<&'static str, &'static str> { Ok("42") } /// let _ = opt().and_then(|s| Some(s.len())); @@ -626,7 +628,7 @@ declare_clippy_lint! { /// /// The correct use would be: /// - /// ```rust + /// ```no_run /// # fn opt() -> Option<&'static str> { Some("42") } /// # fn res() -> Result<&'static str, &'static str> { Ok("42") } /// let _ = opt().map(|s| s.len()); @@ -648,13 +650,13 @@ declare_clippy_lint! { /// `_.find(_)`. /// /// ### Example - /// ```rust + /// ```no_run /// # let vec = vec![1]; /// vec.iter().filter(|x| **x == 0).next(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let vec = vec![1]; /// vec.iter().find(|x| **x == 0); /// ``` @@ -673,13 +675,13 @@ declare_clippy_lint! { /// `_.find(!condition)`. /// /// ### Example - /// ```rust + /// ```no_run /// # let vec = vec![1]; /// vec.iter().skip_while(|x| **x == 0).next(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let vec = vec![1]; /// vec.iter().find(|x| **x != 0); /// ``` @@ -698,7 +700,7 @@ declare_clippy_lint! { /// `_.flat_map(_)` for `Iterator` or `_.and_then(_)` for `Option` /// /// ### Example - /// ```rust + /// ```no_run /// let vec = vec![vec![1]]; /// let opt = Some(5); /// @@ -707,7 +709,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let vec = vec![vec![1]]; /// # let opt = Some(5); /// vec.iter().flat_map(|x| x.iter()); @@ -729,7 +731,7 @@ declare_clippy_lint! { /// less performant. /// /// ### Example - /// ```rust + /// ```no_run /// # #![allow(unused)] /// (0_i32..10) /// .filter(|n| n.checked_add(1).is_some()) @@ -737,7 +739,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # #[allow(unused)] /// (0_i32..10).filter_map(|n| n.checked_add(1)); /// ``` @@ -757,14 +759,14 @@ declare_clippy_lint! { /// less performant. /// /// ### Example - /// ```rust + /// ```no_run /// (0_i32..10) /// .find(|n| n.checked_add(1).is_some()) /// .map(|n| n.checked_add(1).unwrap()); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// (0_i32..10).find_map(|n| n.checked_add(1)); /// ``` #[clippy::version = "1.51.0"] @@ -782,12 +784,12 @@ declare_clippy_lint! { /// `_.find_map(_)`. /// /// ### Example - /// ```rust + /// ```no_run /// (0..3).filter_map(|x| if x == 2 { Some(x) } else { None }).next(); /// ``` /// Can be written as /// - /// ```rust + /// ```no_run /// (0..3).find_map(|x| if x == 2 { Some(x) } else { None }); /// ``` #[clippy::version = "1.36.0"] @@ -804,12 +806,12 @@ declare_clippy_lint! { /// Readability, this can be written more concisely by using `flatten`. /// /// ### Example - /// ```rust + /// ```no_run /// # let iter = vec![vec![0]].into_iter(); /// iter.flat_map(|x| x); /// ``` /// Can be written as - /// ```rust + /// ```no_run /// # let iter = vec![vec![0]].into_iter(); /// iter.flatten(); /// ``` @@ -830,7 +832,7 @@ declare_clippy_lint! { /// * `!_.any(_)`, or `!_.contains(_)` for `is_none()`. /// /// ### Example - /// ```rust + /// ```no_run /// # #![allow(unused)] /// let vec = vec![1]; /// vec.iter().find(|x| **x == 0).is_some(); @@ -839,7 +841,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let vec = vec![1]; /// vec.iter().any(|x| *x == 0); /// @@ -862,13 +864,13 @@ declare_clippy_lint! { /// `_.starts_with(_)`. /// /// ### Example - /// ```rust + /// ```no_run /// let name = "foo"; /// if name.chars().next() == Some('_') {}; /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let name = "foo"; /// if name.starts_with('_') {}; /// ``` @@ -897,13 +899,13 @@ declare_clippy_lint! { /// actually expensive to call or not. /// /// ### Example - /// ```rust + /// ```no_run /// # let foo = Some(String::new()); /// foo.unwrap_or(String::from("empty")); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let foo = Some(String::new()); /// foo.unwrap_or_else(|| String::from("empty")); /// ``` @@ -921,7 +923,7 @@ declare_clippy_lint! { /// You should use `.unwrap_or(…)` instead for clarity. /// /// ### Example - /// ```rust + /// ```no_run /// # let fallback = "fallback"; /// // Result /// # type Error = &'static str; @@ -933,7 +935,7 @@ declare_clippy_lint! { /// let value = option.or(Some(fallback)).unwrap(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # let fallback = "fallback"; /// // Result /// # let result: Result<&str, &str> = Err("error"); @@ -962,7 +964,7 @@ declare_clippy_lint! { /// change the semantics of the program, but you shouldn't rely on that anyway. /// /// ### Example - /// ```rust + /// ```no_run /// # let foo = Some(String::new()); /// # let err_code = "418"; /// # let err_msg = "I'm a teapot"; @@ -975,7 +977,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let foo = Some(String::new()); /// # let err_code = "418"; /// # let err_msg = "I'm a teapot"; @@ -996,7 +998,7 @@ declare_clippy_lint! { /// generics, not for using the `clone` method on a concrete type. /// /// ### Example - /// ```rust + /// ```no_run /// 42u64.clone(); /// ``` #[clippy::version = "pre 1.29.0"] @@ -1017,7 +1019,7 @@ declare_clippy_lint! { /// data. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::rc::Rc; /// let x = Rc::new(1); /// @@ -1025,7 +1027,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # use std::rc::Rc; /// # let x = Rc::new(1); /// Rc::clone(&x); @@ -1047,7 +1049,7 @@ declare_clippy_lint! { /// facilities. /// /// ### Example - /// ```rust + /// ```no_run /// // Generic implementation for `T: Display` is used (slow) /// ["foo", "bar"].iter().map(|s| s.to_string()); /// @@ -1070,7 +1072,7 @@ declare_clippy_lint! { /// /// ### Example /// In an impl block: - /// ```rust + /// ```no_run /// # struct Foo; /// # struct NotAFoo; /// impl Foo { @@ -1080,7 +1082,7 @@ declare_clippy_lint! { /// } /// ``` /// - /// ```rust + /// ```no_run /// # struct Foo; /// struct Bar(Foo); /// impl Foo { @@ -1091,7 +1093,7 @@ declare_clippy_lint! { /// } /// ``` /// - /// ```rust + /// ```no_run /// # struct Foo; /// # struct FooError; /// impl Foo { @@ -1103,14 +1105,14 @@ declare_clippy_lint! { /// ``` /// /// Or in a trait definition: - /// ```rust + /// ```no_run /// pub trait Trait { /// // Bad. The type name must contain `Self` /// fn new(); /// } /// ``` /// - /// ```rust + /// ```no_run /// pub trait Trait { /// // Good. Return type contains `Self` /// fn new() -> Self; @@ -1178,11 +1180,11 @@ declare_clippy_lint! { /// automatically does this without suspicious-looking `unwrap` calls. /// /// ### Example - /// ```rust + /// ```no_run /// let _ = std::iter::empty::<Option<i32>>().filter(Option::is_some).map(Option::unwrap); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let _ = std::iter::empty::<Option<i32>>().flatten(); /// ``` #[clippy::version = "1.53.0"] @@ -1201,7 +1203,7 @@ declare_clippy_lint! { /// but is more readable. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::collections::HashSet; /// # let mut s = HashSet::new(); /// # s.insert(1); @@ -1209,7 +1211,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # use std::collections::HashSet; /// # let mut s = HashSet::new(); /// # s.insert(1); @@ -1231,13 +1233,13 @@ declare_clippy_lint! { /// readable. /// /// ### Example - /// ```rust + /// ```no_run /// let some_vec = vec![0, 1, 2, 3]; /// let bad_vec = some_vec.iter().nth(3); /// let bad_slice = &some_vec[..].iter().nth(3); /// ``` /// The correct use would be: - /// ```rust + /// ```no_run /// let some_vec = vec![0, 1, 2, 3]; /// let bad_vec = some_vec.get(3); /// let bad_slice = &some_vec[..].get(3); @@ -1256,13 +1258,13 @@ declare_clippy_lint! { /// `.nth(x)` is cleaner /// /// ### Example - /// ```rust + /// ```no_run /// let some_vec = vec![0, 1, 2, 3]; /// let bad_vec = some_vec.iter().skip(3).next(); /// let bad_slice = &some_vec[..].iter().skip(3).next(); /// ``` /// The correct use would be: - /// ```rust + /// ```no_run /// let some_vec = vec![0, 1, 2, 3]; /// let bad_vec = some_vec.iter().nth(3); /// let bad_slice = &some_vec[..].iter().nth(3); @@ -1281,13 +1283,13 @@ declare_clippy_lint! { /// `.into_iter()` is simpler with better performance. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::collections::HashSet; /// let mut foo = vec![0, 1, 2, 3]; /// let bar: HashSet<usize> = foo.drain(..).collect(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # use std::collections::HashSet; /// let foo = vec![0, 1, 2, 3]; /// let bar: HashSet<usize> = foo.into_iter().collect(); @@ -1315,13 +1317,13 @@ declare_clippy_lint! { /// `x.get(index).unwrap()` instead of `x[index]`. /// /// ### Example - /// ```rust + /// ```no_run /// let x = vec![2, 3, 5]; /// let last_element = x.get(x.len() - 1); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let x = vec![2, 3, 5]; /// let last_element = x.last(); /// ``` @@ -1351,13 +1353,13 @@ declare_clippy_lint! { /// trait. /// /// ### Example - /// ```rust + /// ```no_run /// let mut some_vec = vec![0, 1, 2, 3]; /// let last = some_vec.get(3).unwrap(); /// *some_vec.get_mut(0).unwrap() = 1; /// ``` /// The correct use would be: - /// ```rust + /// ```no_run /// let mut some_vec = vec![0, 1, 2, 3]; /// let last = some_vec[3]; /// some_vec[0] = 1; @@ -1376,7 +1378,7 @@ declare_clippy_lint! { /// Using `append` instead of `extend` is more concise and faster /// /// ### Example - /// ```rust + /// ```no_run /// let mut a = vec![1, 2, 3]; /// let mut b = vec![4, 5, 6]; /// @@ -1384,7 +1386,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let mut a = vec![1, 2, 3]; /// let mut b = vec![4, 5, 6]; /// @@ -1405,7 +1407,7 @@ declare_clippy_lint! { /// `.push_str(s)` is clearer /// /// ### Example - /// ```rust + /// ```no_run /// let abc = "abc"; /// let def = String::from("def"); /// let mut s = String::new(); @@ -1413,7 +1415,7 @@ declare_clippy_lint! { /// s.extend(def.chars()); /// ``` /// The correct use would be: - /// ```rust + /// ```no_run /// let abc = "abc"; /// let def = String::from("def"); /// let mut s = String::new(); @@ -1435,12 +1437,12 @@ declare_clippy_lint! { /// `.to_vec()` is clearer /// /// ### Example - /// ```rust + /// ```no_run /// let s = [1, 2, 3, 4, 5]; /// let s2: Vec<isize> = s[..].iter().cloned().collect(); /// ``` /// The better use would be: - /// ```rust + /// ```no_run /// let s = [1, 2, 3, 4, 5]; /// let s2: Vec<isize> = s.to_vec(); /// ``` @@ -1460,13 +1462,13 @@ declare_clippy_lint! { /// `_.ends_with(_)`. /// /// ### Example - /// ```rust + /// ```no_run /// # let name = "_"; /// name.chars().last() == Some('_') || name.chars().next_back() == Some('-'); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let name = "_"; /// name.ends_with('_') || name.ends_with('-'); /// ``` @@ -1485,13 +1487,13 @@ declare_clippy_lint! { /// The call is unnecessary. /// /// ### Example - /// ```rust + /// ```no_run /// # fn do_stuff(x: &[i32]) {} /// let x: &[i32] = &[1, 2, 3, 4, 5]; /// do_stuff(x.as_ref()); /// ``` /// The correct use would be: - /// ```rust + /// ```no_run /// # fn do_stuff(x: &[i32]) {} /// let x: &[i32] = &[1, 2, 3, 4, 5]; /// do_stuff(x); @@ -1512,13 +1514,13 @@ declare_clippy_lint! { /// Readability. /// /// ### Example - /// ```rust + /// ```no_run /// # #[allow(unused)] /// (0..3).fold(false, |acc, x| acc || x > 2); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// (0..3).any(|x| x > 2); /// ``` #[clippy::version = "pre 1.29.0"] @@ -1538,14 +1540,14 @@ declare_clippy_lint! { /// operation is being performed. /// /// ### Example - /// ```rust + /// ```no_run /// let _ = (0..3).filter_map(|x| if x > 2 { Some(x) } else { None }); /// /// // As there is no transformation of the argument this could be written as: /// let _ = (0..3).filter(|&x| x > 2); /// ``` /// - /// ```rust + /// ```no_run /// let _ = (0..4).filter_map(|x| Some(x + 1)); /// /// // As there is no conditional check on the argument this could be written as: @@ -1568,14 +1570,14 @@ declare_clippy_lint! { /// operation is being performed. /// /// ### Example - /// ```rust + /// ```no_run /// let _ = (0..3).find_map(|x| if x > 2 { Some(x) } else { None }); /// /// // As there is no transformation of the argument this could be written as: /// let _ = (0..3).find(|&x| x > 2); /// ``` /// - /// ```rust + /// ```no_run /// let _ = (0..4).find_map(|x| Some(x + 1)); /// /// // As there is no conditional check on the argument this could be written as: @@ -1598,13 +1600,13 @@ declare_clippy_lint! { /// `iter_mut` directly. /// /// ### Example - /// ```rust + /// ```no_run /// # let vec = vec![3, 4, 5]; /// (&vec).into_iter(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let vec = vec![3, 4, 5]; /// (&vec).iter(); /// ``` @@ -1625,7 +1627,7 @@ declare_clippy_lint! { /// completion, you can just use `for_each` instead. /// /// ### Example - /// ```rust + /// ```no_run /// let _ = (0..3).map(|x| x + 2).count(); /// ``` #[clippy::version = "1.39.0"] @@ -1647,7 +1649,7 @@ declare_clippy_lint! { /// data, but those are not yet rigorously defined. /// /// ### Example - /// ```rust + /// ```no_run /// // Beware the UB /// use std::mem::MaybeUninit; /// @@ -1656,7 +1658,7 @@ declare_clippy_lint! { /// /// Note that the following is OK: /// - /// ```rust + /// ```no_run /// use std::mem::MaybeUninit; /// /// let _: [MaybeUninit<bool>; 5] = unsafe { @@ -1677,7 +1679,7 @@ declare_clippy_lint! { /// These can be written simply with `saturating_add/sub` methods. /// /// ### Example - /// ```rust + /// ```no_run /// # let y: u32 = 0; /// # let x: u32 = 100; /// let add = x.checked_add(y).unwrap_or(u32::MAX); @@ -1686,7 +1688,7 @@ declare_clippy_lint! { /// /// can be written using dedicated methods for saturating addition/subtraction as: /// - /// ```rust + /// ```no_run /// # let y: u32 = 0; /// # let x: u32 = 100; /// let add = x.saturating_add(y); @@ -1707,7 +1709,7 @@ declare_clippy_lint! { /// This is a no-op, and likely unintended /// /// ### Example - /// ```rust + /// ```no_run /// unsafe { (&() as *const ()).offset(1) }; /// ``` #[clippy::version = "1.41.0"] @@ -1727,7 +1729,7 @@ declare_clippy_lint! { /// symlink in windows. Using `!FileType::is_dir()` is a better way to that intention. /// /// ### Example - /// ```rust + /// ```no_run /// # || { /// let metadata = std::fs::metadata("foo.txt")?; /// let filetype = metadata.file_type(); @@ -1741,7 +1743,7 @@ declare_clippy_lint! { /// /// should be written as: /// - /// ```rust + /// ```no_run /// # || { /// let metadata = std::fs::metadata("foo.txt")?; /// let filetype = metadata.file_type(); @@ -1767,13 +1769,13 @@ declare_clippy_lint! { /// `_.as_deref()`. /// /// ### Example - /// ```rust + /// ```no_run /// # let opt = Some("".to_string()); /// opt.as_ref().map(String::as_str) /// # ; /// ``` /// Can be written as - /// ```rust + /// ```no_run /// # let opt = Some("".to_string()); /// opt.as_deref() /// # ; @@ -1792,14 +1794,14 @@ declare_clippy_lint! { /// These can be shortened into `.get()` /// /// ### Example - /// ```rust + /// ```no_run /// # let a = [1, 2, 3]; /// # let b = vec![1, 2, 3]; /// a[2..].iter().next(); /// b.iter().next(); /// ``` /// should be written as: - /// ```rust + /// ```no_run /// # let a = [1, 2, 3]; /// # let b = vec![1, 2, 3]; /// a.get(2); @@ -1820,14 +1822,14 @@ declare_clippy_lint! { /// It's less clear that we are pushing a single character. /// /// ### Example - /// ```rust + /// ```no_run /// # let mut string = String::new(); /// string.insert_str(0, "R"); /// string.push_str("R"); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let mut string = String::new(); /// string.insert(0, 'R'); /// string.push('R'); @@ -1860,14 +1862,14 @@ declare_clippy_lint! { /// side effects. Eagerly evaluating them can change the semantics of the program. /// /// ### Example - /// ```rust + /// ```no_run /// // example code where clippy issues a warning /// let opt: Option<u32> = None; /// /// opt.unwrap_or_else(|| 42); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let opt: Option<u32> = None; /// /// opt.unwrap_or(42); @@ -1886,11 +1888,11 @@ declare_clippy_lint! { /// Using `try_for_each` instead is more readable and idiomatic. /// /// ### Example - /// ```rust + /// ```no_run /// (0..3).map(|t| Err(t)).collect::<Result<(), _>>(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// (0..3).try_for_each(|t| Err(t)); /// ``` #[clippy::version = "1.49.0"] @@ -1909,7 +1911,7 @@ declare_clippy_lint! { /// [FromIterator documentation](https://doc.rust-lang.org/std/iter/trait.FromIterator.html) /// /// ### Example - /// ```rust + /// ```no_run /// let five_fives = std::iter::repeat(5).take(5); /// /// let v = Vec::from_iter(five_fives); @@ -1917,7 +1919,7 @@ declare_clippy_lint! { /// assert_eq!(v, vec![5, 5, 5, 5, 5]); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let five_fives = std::iter::repeat(5).take(5); /// /// let v: Vec<i32> = five_fives.collect(); @@ -1939,7 +1941,7 @@ declare_clippy_lint! { /// inside `inspect` at the beginning of the closure in `for_each`. /// /// ### Example - /// ```rust + /// ```no_run /// [1,2,3,4,5].iter() /// .inspect(|&x| println!("inspect the number: {}", x)) /// .for_each(|&x| { @@ -1947,7 +1949,7 @@ declare_clippy_lint! { /// }); /// ``` /// Can be written as - /// ```rust + /// ```no_run /// [1,2,3,4,5].iter() /// .for_each(|&x| { /// println!("inspect the number: {}", x); @@ -1968,12 +1970,12 @@ declare_clippy_lint! { /// Readability, this can be written more concisely by using `flatten`. /// /// ### Example - /// ```rust + /// ```no_run /// # let iter = vec![Some(1)].into_iter(); /// iter.filter_map(|x| x); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # let iter = vec![Some(1)].into_iter(); /// iter.flatten(); /// ``` @@ -1991,12 +1993,12 @@ declare_clippy_lint! { /// It can be written more concisely without the call to `map`. /// /// ### Example - /// ```rust + /// ```no_run /// let x = [1, 2, 3]; /// let y: Vec<_> = x.iter().map(|x| x).map(|x| 2*x).collect(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let x = [1, 2, 3]; /// let y: Vec<_> = x.iter().map(|x| 2*x).collect(); /// ``` @@ -2015,13 +2017,13 @@ declare_clippy_lint! { /// readable. /// /// ### Example - /// ```rust + /// ```no_run /// # #[allow(unused)] /// "Hello".bytes().nth(3); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # #[allow(unused)] /// "Hello".as_bytes().get(3); /// ``` @@ -2040,13 +2042,13 @@ declare_clippy_lint! { /// to why we are calling `to_vec` on something that is already a `Vec` or calling `to_owned` on something that is already owned. /// /// ### Example - /// ```rust + /// ```no_run /// let a = vec![1, 2, 3]; /// let b = a.to_vec(); /// let c = a.to_owned(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let a = vec![1, 2, 3]; /// let b = a.clone(); /// let c = a.clone(); @@ -2066,7 +2068,7 @@ declare_clippy_lint! { /// readable. /// /// ### Example - /// ```rust + /// ```no_run /// # #![allow(unused)] /// let some_vec = vec![0, 1, 2, 3]; /// @@ -2075,7 +2077,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let some_vec = vec![0, 1, 2, 3]; /// /// some_vec.len(); @@ -2104,7 +2106,7 @@ declare_clippy_lint! { /// was the original intent, using `into_owned` instead. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::borrow::Cow; /// let s = "Hello world!"; /// let cow = Cow::Borrowed(s); @@ -2113,7 +2115,7 @@ declare_clippy_lint! { /// assert!(matches!(data, Cow::Borrowed(_))) /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # use std::borrow::Cow; /// let s = "Hello world!"; /// let cow = Cow::Borrowed(s); @@ -2122,7 +2124,7 @@ declare_clippy_lint! { /// assert!(matches!(data, Cow::Borrowed(_))) /// ``` /// or - /// ```rust + /// ```no_run /// # use std::borrow::Cow; /// let s = "Hello world!"; /// let cow = Cow::Borrowed(s); @@ -2146,7 +2148,7 @@ declare_clippy_lint! { /// likely to be intended as a different number. /// /// ### Example - /// ```rust + /// ```no_run /// # let s = ""; /// for x in s.splitn(1, ":") { /// // .. @@ -2154,7 +2156,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let s = ""; /// for x in s.splitn(2, ":") { /// // .. @@ -2174,12 +2176,12 @@ declare_clippy_lint! { /// These are both harder to read, as well as less performant. /// /// ### Example - /// ```rust + /// ```no_run /// let x: String = std::iter::repeat('x').take(10).collect(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let x: String = "x".repeat(10); /// ``` #[clippy::version = "1.54.0"] @@ -2231,13 +2233,13 @@ declare_clippy_lint! { /// The function `split` is simpler and there is no performance difference in these cases, considering /// that both functions return a lazy iterator. /// ### Example - /// ```rust + /// ```no_run /// let str = "key=value=add"; /// let _ = str.splitn(3, '=').next().unwrap(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let str = "key=value=add"; /// let _ = str.split('=').next().unwrap(); /// ``` @@ -2261,13 +2263,13 @@ declare_clippy_lint! { /// [#8148](https://github.com/rust-lang/rust-clippy/issues/8148). /// /// ### Example - /// ```rust + /// ```no_run /// let path = std::path::Path::new("x"); /// foo(&path.to_string_lossy().to_string()); /// fn foo(s: &str) {} /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let path = std::path::Path::new("x"); /// foo(&path.to_string_lossy()); /// fn foo(s: &str) {} @@ -2286,13 +2288,13 @@ declare_clippy_lint! { /// `.collect::<String>()` is more concise and might be more performant /// /// ### Example - /// ```rust + /// ```no_run /// let vector = vec!["hello", "world"]; /// let output = vector.iter().map(|item| item.to_uppercase()).collect::<Vec<String>>().join(""); /// println!("{}", output); /// ``` /// The correct use would be: - /// ```rust + /// ```no_run /// let vector = vec!["hello", "world"]; /// let output = vector.iter().map(|item| item.to_uppercase()).collect::<String>(); /// println!("{}", output); @@ -2319,13 +2321,13 @@ declare_clippy_lint! { /// Redundant code and improving readability. /// /// ### Example - /// ```rust + /// ```no_run /// let a = Some(&1); /// let b = a.as_deref(); // goes from Option<&i32> to Option<&i32> /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let a = Some(&1); /// let b = a; /// ``` @@ -2345,13 +2347,13 @@ declare_clippy_lint! { /// `is_digit(..)` is slower and requires specifying the radix. /// /// ### Example - /// ```rust + /// ```no_run /// let c: char = '6'; /// c.is_digit(10); /// c.is_digit(16); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let c: char = '6'; /// c.is_ascii_digit(); /// c.is_ascii_hexdigit(); @@ -2371,12 +2373,12 @@ declare_clippy_lint! { /// In this case the modification is useless as it's a temporary that cannot be read from afterwards. /// /// ### Example - /// ```rust + /// ```no_run /// let x = Some(3); /// x.as_ref().take(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let x = Some(3); /// x.as_ref(); /// ``` @@ -2394,7 +2396,7 @@ declare_clippy_lint! { /// It's either a mistake or confusing. /// /// ### Example - /// ```rust + /// ```no_run /// "1234".replace("12", "12"); /// "1234".replacen("12", "12", 1); /// ``` @@ -2417,12 +2419,12 @@ declare_clippy_lint! { /// to account for similar patterns. /// /// ### Example - /// ```rust + /// ```no_run /// let x = true; /// x.then_some("a").unwrap_or("b"); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let x = true; /// if x { "a" } else { "b" }; /// ``` @@ -2444,12 +2446,12 @@ declare_clippy_lint! { /// /// ### Example /// - /// ```rust + /// ```no_run /// let a = [123].iter(); /// let b = Some(123).into_iter(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// use std::iter; /// let a = iter::once(&123); /// let b = iter::once(123); @@ -2475,13 +2477,13 @@ declare_clippy_lint! { /// /// ### Example /// - /// ```rust + /// ```no_run /// use std::{slice, option}; /// let a: slice::Iter<i32> = [].iter(); /// let f: option::IntoIter<i32> = None.into_iter(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// use std::iter; /// let a: iter::Empty<i32> = iter::empty(); /// let b: iter::Empty<i32> = iter::empty(); @@ -2511,7 +2513,7 @@ declare_clippy_lint! { /// faster in those cases. /// /// ### Example - /// ```rust + /// ```no_run /// # let vec = vec![1_u8]; /// let count = vec.iter().filter(|x| **x == 0u8).count(); /// ``` @@ -2537,12 +2539,12 @@ declare_clippy_lint! { /// `str::len()`. /// /// ### Example - /// ```rust + /// ```no_run /// "hello".bytes().count(); /// String::from("hello").bytes().count(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// "hello".len(); /// String::from("hello").len(); /// ``` @@ -2561,13 +2563,13 @@ declare_clippy_lint! { /// `ends_with` is case-sensitive and may not detect files with a valid extension. /// /// ### Example - /// ```rust + /// ```no_run /// fn is_rust_file(filename: &str) -> bool { /// filename.ends_with(".rs") /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// fn is_rust_file(filename: &str) -> bool { /// let filename = std::path::Path::new(filename); /// filename.extension() @@ -2590,13 +2592,13 @@ declare_clippy_lint! { /// result. /// /// ### Example - /// ```rust + /// ```no_run /// let x = vec![2, 3, 5]; /// let first_element = x.get(0); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let x = vec![2, 3, 5]; /// let first_element = x.first(); /// ``` @@ -2616,13 +2618,13 @@ declare_clippy_lint! { /// Concise code helps focusing on behavior instead of boilerplate. /// /// ### Examples - /// ```rust + /// ```no_run /// let foo: Option<i32> = None; /// foo.map_or(Err("error"), |v| Ok(v)); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// let foo: Option<i32> = None; /// foo.ok_or("error"); /// ``` @@ -2642,7 +2644,7 @@ declare_clippy_lint! { /// Readability, this can be written more concisely /// /// ### Example - /// ```rust + /// ```no_run /// let x = vec![42, 43]; /// let y = x.iter(); /// let z = y.map(|i| *i); @@ -2650,7 +2652,7 @@ declare_clippy_lint! { /// /// The correct use would be: /// - /// ```rust + /// ```no_run /// let x = vec![42, 43]; /// let y = x.iter(); /// let z = y.cloned(); @@ -2670,7 +2672,7 @@ declare_clippy_lint! { /// /// ### Example /// Before: - /// ```rust + /// ```no_run /// use std::fmt; /// /// #[derive(Debug)] @@ -2772,7 +2774,7 @@ declare_clippy_lint! { /// guarantee. /// /// ### Example - /// ```rust + /// ```no_run /// use std::sync::{Arc, Mutex}; /// /// let mut value_rc = Arc::new(Mutex::new(42_u8)); @@ -2782,7 +2784,7 @@ declare_clippy_lint! { /// *value += 1; /// ``` /// Use instead: - /// ```rust + /// ```no_run /// use std::sync::{Arc, Mutex}; /// /// let mut value_rc = Arc::new(Mutex::new(42_u8)); @@ -2807,7 +2809,7 @@ declare_clippy_lint! { /// necessary. I don't know the worst case. /// /// ### Example - /// ```rust + /// ```no_run /// use std::fs::OpenOptions; /// /// OpenOptions::new().read(true).truncate(true); @@ -2828,7 +2830,7 @@ declare_clippy_lint! { /// previous defined path. /// /// ### Example - /// ```rust + /// ```no_run /// use std::path::PathBuf; /// /// let mut x = PathBuf::from("/foo"); @@ -2837,7 +2839,7 @@ declare_clippy_lint! { /// ``` /// Could be written: /// - /// ```rust + /// ```no_run /// use std::path::PathBuf; /// /// let mut x = PathBuf::from("/foo"); @@ -2859,13 +2861,13 @@ declare_clippy_lint! { /// The code is better expressed with `.enumerate()`. /// /// ### Example - /// ```rust + /// ```no_run /// # let x = vec![1]; /// let _ = x.iter().zip(0..x.len()); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # let x = vec![1]; /// let _ = x.iter().enumerate(); /// ``` @@ -2890,13 +2892,13 @@ declare_clippy_lint! { /// the string is the intention behind this, `clone()` should be used. /// /// ### Example - /// ```rust + /// ```no_run /// fn main() { /// let x = String::from("hello world").repeat(1); /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// fn main() { /// let x = String::from("hello world").clone(); /// } @@ -2930,12 +2932,12 @@ declare_clippy_lint! { /// issue linked above. /// /// ### Example - /// ```rust + /// ```no_run /// let mut vec = vec![2, 1, 3]; /// vec.sort(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let mut vec = vec![2, 1, 3]; /// vec.sort_unstable(); /// ``` @@ -2963,7 +2965,7 @@ declare_clippy_lint! { /// assert_eq!(any_box.type_id(), TypeId::of::<i32>()); // ⚠️ this fails! /// ``` /// Use instead: - /// ```rust + /// ```no_run /// use std::any::{Any, TypeId}; /// /// let any_box: Box<dyn Any> = Box::new(42_i32); @@ -2984,7 +2986,7 @@ declare_clippy_lint! { /// Hashing a unit value doesn't do anything as the implementation of `Hash` for `()` is a no-op. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::hash::Hash; /// # use std::collections::hash_map::DefaultHasher; /// # enum Foo { Empty, WithValue(u8) } @@ -2997,7 +2999,7 @@ declare_clippy_lint! { /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # use std::hash::Hash; /// # use std::collections::hash_map::DefaultHasher; /// # enum Foo { Empty, WithValue(u8) } @@ -3030,14 +3032,14 @@ declare_clippy_lint! { /// imported by a use statement, then it will need to be added manually. /// /// ### Example - /// ```rust + /// ```no_run /// # struct A; /// # impl A { fn foo(&self) {} } /// # let mut vec: Vec<A> = Vec::new(); /// vec.sort_by(|a, b| a.foo().cmp(&b.foo())); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # struct A; /// # impl A { fn foo(&self) {} } /// # let mut vec: Vec<A> = Vec::new(); @@ -3057,12 +3059,12 @@ declare_clippy_lint! { /// This is probably an argument inversion mistake. /// /// ### Example - /// ```rust + /// ```no_run /// vec![1, 2, 3, 4, 5].resize(0, 5) /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// vec![1, 2, 3, 4, 5].clear() /// ``` #[clippy::version = "1.46.0"] @@ -3111,14 +3113,14 @@ declare_clippy_lint! { /// /// ### Example /// - /// ``` + /// ```no_run /// # use std::collections::HashMap; /// let map: HashMap<u32, u32> = HashMap::new(); /// let values = map.iter().map(|(_, value)| value).collect::<Vec<_>>(); /// ``` /// /// Use instead: - /// ``` + /// ```no_run /// # use std::collections::HashMap; /// let map: HashMap<u32, u32> = HashMap::new(); /// let values = map.values().collect::<Vec<_>>(); @@ -3184,14 +3186,14 @@ declare_clippy_lint! { /// this exact scenario. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::io; /// fn foo<T: io::Seek>(t: &mut T) { /// t.seek(io::SeekFrom::Start(0)); /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # use std::io; /// fn foo<T: io::Seek>(t: &mut T) { /// t.rewind(); @@ -3213,12 +3215,12 @@ declare_clippy_lint! { /// when this allocation may not be needed. /// /// ### Example - /// ```rust + /// ```no_run /// # let iterator = vec![1].into_iter(); /// let len = iterator.collect::<Vec<_>>().len(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # let iterator = vec![1].into_iter(); /// let len = iterator.count(); /// ``` @@ -3241,11 +3243,11 @@ declare_clippy_lint! { /// which is likely not what was intended. /// /// ### Example - /// ```rust + /// ```no_run /// std::process::Command::new("echo").arg("-n hello").spawn().unwrap(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// std::process::Command::new("echo").args(["-n", "hello"]).spawn().unwrap(); /// ``` #[clippy::version = "1.69.0"] @@ -3264,12 +3266,12 @@ declare_clippy_lint! { /// Calling `.clear()` also makes the intent clearer. /// /// ### Example - /// ```rust + /// ```no_run /// let mut v = vec![1, 2, 3]; /// v.drain(..); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// let mut v = vec![1, 2, 3]; /// v.clear(); /// ``` @@ -3287,12 +3289,12 @@ declare_clippy_lint! { /// `.next_back()` is cleaner. /// /// ### Example - /// ```rust + /// ```no_run /// # let foo = [0; 10]; /// foo.iter().rev().next(); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # let foo = [0; 10]; /// foo.iter().next_back(); /// ``` @@ -3320,13 +3322,13 @@ declare_clippy_lint! { /// to keep the capacity on the original `Vec`. /// /// ### Example - /// ```rust + /// ```no_run /// fn remove_all(v: &mut Vec<i32>) -> Vec<i32> { /// v.drain(..).collect() /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// use std::mem; /// fn remove_all(v: &mut Vec<i32>) -> Vec<i32> { /// mem::take(v) @@ -3354,11 +3356,11 @@ declare_clippy_lint! { /// desirable in those cases. /// /// ### Example - /// ```rust + /// ```no_run /// vec![1, 2, 3].iter().fold(Some(0i32), |sum, i| sum?.checked_add(*i)); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// vec![1, 2, 3].iter().try_fold(0i32, |sum, i| sum.checked_add(*i)); /// ``` #[clippy::version = "1.72.0"] @@ -3410,12 +3412,12 @@ declare_clippy_lint! { /// for situations where that additional performance is absolutely necessary. /// /// ### Example - /// ```rust + /// ```no_run /// # let c = 'c'; /// "\\.+*?()|[]{}^$#&-~".chars().any(|x| x == c); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # let c = 'c'; /// matches!(c, '\\' | '.' | '+' | '*' | '(' | ')' | '|' | '[' | ']' | '{' | '}' | '^' | '$' | '#' | '&' | '-' | '~'); /// ``` @@ -3439,13 +3441,13 @@ declare_clippy_lint! { /// so it can be safely ignored or unwrapped. /// /// ### Example - /// ```rust + /// ```no_run /// fn hex_encode(bytes: &[u8]) -> String { /// bytes.iter().map(|b| format!("{b:02X}")).collect() /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// use std::fmt::Write; /// fn hex_encode(bytes: &[u8]) -> String { /// bytes.iter().fold(String::new(), |mut output, b| { @@ -3469,7 +3471,7 @@ declare_clippy_lint! { /// nothing. If not, the call should be removed. /// /// ### Example - /// ```rust + /// ```no_run /// let v = vec![1, 2, 3]; /// let x = v.iter().skip(0).collect::<Vec<_>>(); /// let y = v.iter().collect::<Vec<_>>(); @@ -3495,13 +3497,13 @@ declare_clippy_lint! { /// This can create differing behavior, so better safe than sorry. /// /// ### Example - /// ```rust + /// ```no_run /// # fn really_expensive_fn(i: i32) -> i32 { i } /// # let v = vec![]; /// _ = v.into_iter().filter_map(|i| (i % 2 == 0).then(|| really_expensive_fn(i))); /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # fn really_expensive_fn(i: i32) -> i32 { i } /// # let v = vec![]; /// _ = v.into_iter().filter(|i| i % 2 == 0).map(|i| really_expensive_fn(i)); @@ -3521,7 +3523,7 @@ declare_clippy_lint! { /// can access the lock while this writer is active. /// /// ### Example - /// ```rust + /// ```no_run /// use std::sync::RwLock; /// fn assert_is_zero(lock: &RwLock<i32>) { /// let num = lock.write().unwrap(); @@ -3530,7 +3532,7 @@ declare_clippy_lint! { /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// use std::sync::RwLock; /// fn assert_is_zero(lock: &RwLock<i32>) { /// let num = lock.read().unwrap(); @@ -3554,11 +3556,11 @@ declare_clippy_lint! { /// This is most likely not what the user intended to do. /// /// ### Example - /// ```rust + /// ```no_run /// for _ in [1, 2, 3].iter().take(4) {} /// ``` /// Use instead: - /// ```rust + /// ```no_run /// for _ in [1, 2, 3].iter() {} /// ``` #[clippy::version = "1.74.0"] @@ -3587,14 +3589,14 @@ declare_clippy_lint! { /// therefore ignored. /// /// ### Example - /// ```rust + /// ```no_run /// # use std::path::Path; /// fn is_markdown(path: &Path) -> bool { /// path.ends_with(".md") /// } /// ``` /// Use instead: - /// ```rust + /// ```no_run /// # use std::path::Path; /// fn is_markdown(path: &Path) -> bool { /// path.extension().is_some_and(|ext| ext == "md") @@ -3614,14 +3616,14 @@ declare_clippy_lint! { /// The `as_str()` conversion is pointless and can be removed for simplicity and cleanliness. /// /// ### Example - /// ```rust + /// ```no_run /// # #![allow(unused)] /// let owned_string = "This is a string".to_owned(); /// owned_string.as_str().as_bytes(); /// ``` /// /// Use instead: - /// ```rust + /// ```no_run /// # #![allow(unused)] /// let owned_string = "This is a string".to_owned(); /// owned_string.as_bytes(); @@ -3632,6 +3634,55 @@ declare_clippy_lint! { "`as_str` used to call a method on `str` that is also available on `String`" } +declare_clippy_lint! { + /// ### What it does + /// Checks for usage of `waker.clone().wake()` + /// + /// ### Why is this bad? + /// Cloning the waker is not necessary, `wake_by_ref()` enables the same operation + /// without extra cloning/dropping. + /// + /// ### Example + /// ```rust,ignore + /// waker.clone().wake(); + /// ``` + /// Should be written + /// ```rust,ignore + /// waker.wake_by_ref(); + /// ``` + #[clippy::version = "1.75.0"] + pub WAKER_CLONE_WAKE, + perf, + "cloning a `Waker` only to wake it" +} + +declare_clippy_lint! { + /// ### What it does + /// Checks for calls to `TryInto::try_into` and `TryFrom::try_from` when their infallible counterparts + /// could be used. + /// + /// ### Why is this bad? + /// In those cases, the `TryInto` and `TryFrom` trait implementation is a blanket impl that forwards + /// to `Into` or `From`, which always succeeds. + /// The returned `Result<_, Infallible>` requires error handling to get the contained value + /// even though the conversion can never fail. + /// + /// ### Example + /// ```rust + /// let _: Result<i64, _> = 1i32.try_into(); + /// let _: Result<i64, _> = <_>::try_from(1i32); + /// ``` + /// Use `from`/`into` instead: + /// ```rust + /// let _: i64 = 1i32.into(); + /// let _: i64 = <_>::from(1i32); + /// ``` + #[clippy::version = "1.75.0"] + pub UNNECESSARY_FALLIBLE_CONVERSIONS, + style, + "calling the `try_from` and `try_into` trait methods when `From`/`Into` is implemented" +} + pub struct Methods { avoid_breaking_exported_api: bool, msrv: Msrv, @@ -3777,6 +3828,8 @@ impl_lint_pass!(Methods => [ ITER_OUT_OF_BOUNDS, PATH_ENDS_WITH_EXT, REDUNDANT_AS_STR, + WAKER_CLONE_WAKE, + UNNECESSARY_FALLIBLE_CONVERSIONS, ]); /// Extracts a method call name, args, and `Span` of the method name. @@ -3803,6 +3856,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods { match expr.kind { hir::ExprKind::Call(func, args) => { from_iter_instead_of_collect::check(cx, expr, args, func); + unnecessary_fallible_conversions::check_function(cx, expr, func); }, hir::ExprKind::MethodCall(method_call, receiver, args, _) => { let method_span = method_call.ident.span; @@ -4292,6 +4346,9 @@ impl Methods { } unnecessary_lazy_eval::check(cx, expr, recv, arg, "then_some"); }, + ("try_into", []) if is_trait_method(cx, expr, sym::TryInto) => { + unnecessary_fallible_conversions::check_method(cx, expr); + } ("to_owned", []) => { if !suspicious_to_owned::check(cx, expr, recv) { implicit_clone::check(cx, name, expr, recv); @@ -4365,6 +4422,9 @@ impl Methods { } unnecessary_literal_unwrap::check(cx, expr, recv, name, args); }, + ("wake", []) => { + waker_clone_wake::check(cx, expr, recv); + } ("write", []) => { readonly_write_lock::check(cx, expr, recv); } diff --git a/clippy_lints/src/methods/needless_collect.rs b/clippy_lints/src/methods/needless_collect.rs index dbd965d6506..a1f8e27654f 100644 --- a/clippy_lints/src/methods/needless_collect.rs +++ b/clippy_lints/src/methods/needless_collect.rs @@ -207,11 +207,10 @@ fn is_is_empty_sig(cx: &LateContext<'_>, call_id: HirId) -> bool { /// Checks if `<iter_ty as Iterator>::Item` is the same as `<collect_ty as IntoIter>::Item` fn iterates_same_ty<'tcx>(cx: &LateContext<'tcx>, iter_ty: Ty<'tcx>, collect_ty: Ty<'tcx>) -> bool { - let item = Symbol::intern("Item"); if let Some(iter_trait) = cx.tcx.get_diagnostic_item(sym::Iterator) && let Some(into_iter_trait) = cx.tcx.get_diagnostic_item(sym::IntoIterator) - && let Some(iter_item_ty) = make_normalized_projection(cx.tcx, cx.param_env, iter_trait, item, [iter_ty]) - && let Some(into_iter_item_proj) = make_projection(cx.tcx, into_iter_trait, item, [collect_ty]) + && let Some(iter_item_ty) = make_normalized_projection(cx.tcx, cx.param_env, iter_trait, sym::Item, [iter_ty]) + && let Some(into_iter_item_proj) = make_projection(cx.tcx, into_iter_trait, sym::Item, [collect_ty]) && let Ok(into_iter_item_ty) = cx.tcx.try_normalize_erasing_regions( cx.param_env, Ty::new_projection(cx.tcx,into_iter_item_proj.def_id, into_iter_item_proj.args) @@ -233,9 +232,12 @@ fn is_contains_sig(cx: &LateContext<'_>, call_id: HirId, iter_expr: &Expr<'_>) - && let [_, search_ty] = *sig.skip_binder().inputs() && let ty::Ref(_, search_ty, Mutability::Not) = *cx.tcx.erase_late_bound_regions(sig.rebind(search_ty)).kind() && let Some(iter_trait) = cx.tcx.get_diagnostic_item(sym::Iterator) - && let Some(iter_item) = cx.tcx - .associated_items(iter_trait) - .find_by_name_and_kind(cx.tcx, Ident::with_dummy_span(Symbol::intern("Item")), AssocKind::Type, iter_trait) + && let Some(iter_item) = cx.tcx.associated_items(iter_trait).find_by_name_and_kind( + cx.tcx, + Ident::with_dummy_span(sym::Item), + AssocKind::Type, + iter_trait, + ) && let args = cx.tcx.mk_args(&[GenericArg::from(typeck.expr_ty_adjusted(iter_expr))]) && let proj_ty = Ty::new_projection(cx.tcx,iter_item.def_id, args) && let Ok(item_ty) = cx.tcx.try_normalize_erasing_regions(cx.param_env, proj_ty) diff --git a/clippy_lints/src/methods/option_as_ref_deref.rs b/clippy_lints/src/methods/option_as_ref_deref.rs index d0c27f9631f..7b81d4571b2 100644 --- a/clippy_lints/src/methods/option_as_ref_deref.rs +++ b/clippy_lints/src/methods/option_as_ref_deref.rs @@ -1,5 +1,5 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet; use clippy_utils::ty::is_type_diagnostic_item; use clippy_utils::{match_def_path, path_to_local_id, paths, peel_blocks}; diff --git a/clippy_lints/src/methods/option_map_unwrap_or.rs b/clippy_lints/src/methods/option_map_unwrap_or.rs index fcbe005fb28..ebb0a7b562d 100644 --- a/clippy_lints/src/methods/option_map_unwrap_or.rs +++ b/clippy_lints/src/methods/option_map_unwrap_or.rs @@ -1,5 +1,5 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_then; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet_with_applicability; use clippy_utils::ty::{is_copy, is_type_diagnostic_item}; use rustc_data_structures::fx::FxHashSet; diff --git a/clippy_lints/src/methods/path_ends_with_ext.rs b/clippy_lints/src/methods/path_ends_with_ext.rs index 3347c8c1620..9ec0ef0ea39 100644 --- a/clippy_lints/src/methods/path_ends_with_ext.rs +++ b/clippy_lints/src/methods/path_ends_with_ext.rs @@ -1,7 +1,6 @@ use super::PATH_ENDS_WITH_EXT; +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::msrvs; -use clippy_utils::msrvs::Msrv; use clippy_utils::source::snippet; use clippy_utils::ty::is_type_diagnostic_item; use rustc_ast::{LitKind, StrStyle}; diff --git a/clippy_lints/src/methods/str_splitn.rs b/clippy_lints/src/methods/str_splitn.rs index 7016ad0a80f..6e00e0fd1fb 100644 --- a/clippy_lints/src/methods/str_splitn.rs +++ b/clippy_lints/src/methods/str_splitn.rs @@ -1,6 +1,6 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::consts::{constant, Constant}; use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then}; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet_with_context; use clippy_utils::usage::local_used_after_expr; use clippy_utils::visitors::{for_each_expr_with_closures, Descend}; @@ -115,7 +115,7 @@ fn check_manual_split_once( /// checks for /// -/// ``` +/// ```no_run /// let mut iter = "a.b.c".splitn(2, '.'); /// let a = iter.next(); /// let b = iter.next(); diff --git a/clippy_lints/src/methods/string_lit_chars_any.rs b/clippy_lints/src/methods/string_lit_chars_any.rs index 70da6ad58bd..fb8075e2362 100644 --- a/clippy_lints/src/methods/string_lit_chars_any.rs +++ b/clippy_lints/src/methods/string_lit_chars_any.rs @@ -1,5 +1,5 @@ +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_then; -use clippy_utils::msrvs::{Msrv, MATCHES_MACRO}; use clippy_utils::source::snippet_opt; use clippy_utils::{is_from_proc_macro, is_trait_method, path_to_local}; use itertools::Itertools; @@ -19,7 +19,7 @@ pub(super) fn check<'tcx>( body: &Expr<'_>, msrv: &Msrv, ) { - if msrv.meets(MATCHES_MACRO) + if msrv.meets(msrvs::MATCHES_MACRO) && is_trait_method(cx, expr, sym::Iterator) && let PatKind::Binding(_, arg, _, _) = param.pat.kind && let ExprKind::Lit(lit_kind) = recv.kind diff --git a/clippy_lints/src/methods/unnecessary_fallible_conversions.rs b/clippy_lints/src/methods/unnecessary_fallible_conversions.rs new file mode 100644 index 00000000000..6660ad215d8 --- /dev/null +++ b/clippy_lints/src/methods/unnecessary_fallible_conversions.rs @@ -0,0 +1,119 @@ +use clippy_utils::diagnostics::span_lint_and_sugg; +use clippy_utils::get_parent_expr; +use clippy_utils::ty::implements_trait; +use rustc_errors::Applicability; +use rustc_hir::{Expr, ExprKind}; +use rustc_lint::LateContext; +use rustc_middle::ty; +use rustc_span::{sym, Span}; + +use super::UNNECESSARY_FALLIBLE_CONVERSIONS; + +/// What function is being called and whether that call is written as a method call or a function +/// call +#[derive(Copy, Clone)] +#[expect(clippy::enum_variant_names)] +enum FunctionKind { + /// `T::try_from(U)` + TryFromFunction, + /// `t.try_into()` + TryIntoMethod, + /// `U::try_into(t)` + TryIntoFunction, +} + +fn check<'tcx>( + cx: &LateContext<'tcx>, + expr: &Expr<'_>, + node_args: ty::GenericArgsRef<'tcx>, + kind: FunctionKind, + primary_span: Span, +) { + if let &[self_ty, other_ty] = node_args.as_slice() + // useless_conversion already warns `T::try_from(T)`, so ignore it here + && self_ty != other_ty + && let Some(self_ty) = self_ty.as_type() + && let Some(from_into_trait) = cx.tcx.get_diagnostic_item(match kind { + FunctionKind::TryFromFunction => sym::From, + FunctionKind::TryIntoMethod | FunctionKind::TryIntoFunction => sym::Into, + }) + // If `T: TryFrom<U>` and `T: From<U>` both exist, then that means that the `TryFrom` + // _must_ be from the blanket impl and cannot have been manually implemented + // (else there would be conflicting impls, even with #![feature(spec)]), so we don't even need to check + // what `<T as TryFrom<U>>::Error` is: it's always `Infallible` + && implements_trait(cx, self_ty, from_into_trait, &[other_ty]) + { + let parent_unwrap_call = get_parent_expr(cx, expr) + .and_then(|parent| { + if let ExprKind::MethodCall(path, .., span) = parent.kind + && let sym::unwrap | sym::expect = path.ident.name + { + Some(span) + } else { + None + } + }); + + let (sugg, span, applicability) = match kind { + FunctionKind::TryIntoMethod if let Some(unwrap_span) = parent_unwrap_call => { + // Extend the span to include the unwrap/expect call: + // `foo.try_into().expect("..")` + // ^^^^^^^^^^^^^^^^^^^^^^^ + // + // `try_into().unwrap()` specifically can be trivially replaced with just `into()`, + // so that can be machine-applicable + + ("into()", primary_span.with_hi(unwrap_span.hi()), Applicability::MachineApplicable) + } + FunctionKind::TryFromFunction => ("From::from", primary_span, Applicability::Unspecified), + FunctionKind::TryIntoFunction => ("Into::into", primary_span, Applicability::Unspecified), + FunctionKind::TryIntoMethod => ("into", primary_span, Applicability::Unspecified), + }; + + span_lint_and_sugg( + cx, + UNNECESSARY_FALLIBLE_CONVERSIONS, + span, + "use of a fallible conversion when an infallible one could be used", + "use", + sugg.into(), + applicability + ); + } +} + +/// Checks method call exprs: +/// - `0i32.try_into()` +pub(super) fn check_method(cx: &LateContext<'_>, expr: &Expr<'_>) { + if let ExprKind::MethodCall(path, ..) = expr.kind { + check( + cx, + expr, + cx.typeck_results().node_args(expr.hir_id), + FunctionKind::TryIntoMethod, + path.ident.span, + ); + } +} + +/// Checks function call exprs: +/// - `<i64 as TryFrom<_>>::try_from(0i32)` +/// - `<_ as TryInto<i64>>::try_into(0i32)` +pub(super) fn check_function(cx: &LateContext<'_>, expr: &Expr<'_>, callee: &Expr<'_>) { + if let ExprKind::Path(ref qpath) = callee.kind + && let Some(item_def_id) = cx.qpath_res(qpath, callee.hir_id).opt_def_id() + && let Some(trait_def_id) = cx.tcx.trait_of_item(item_def_id) + { + check( + cx, + expr, + cx.typeck_results().node_args(callee.hir_id), + match cx.tcx.get_diagnostic_name(trait_def_id) { + Some(sym::TryFrom) => FunctionKind::TryFromFunction, + Some(sym::TryInto) => FunctionKind::TryIntoFunction, + _ => return, + }, + callee.span, + ); + } +} diff --git a/clippy_lints/src/methods/unnecessary_sort_by.rs b/clippy_lints/src/methods/unnecessary_sort_by.rs index e62a65a2712..79bff39379c 100644 --- a/clippy_lints/src/methods/unnecessary_sort_by.rs +++ b/clippy_lints/src/methods/unnecessary_sort_by.rs @@ -6,7 +6,8 @@ use if_chain::if_chain; use rustc_errors::Applicability; use rustc_hir::{Closure, Expr, ExprKind, Mutability, Param, Pat, PatKind, Path, PathSegment, QPath}; use rustc_lint::LateContext; -use rustc_middle::ty::{self, GenericArgKind}; +use rustc_middle::ty; +use rustc_middle::ty::GenericArgKind; use rustc_span::sym; use rustc_span::symbol::Ident; use std::iter; diff --git a/clippy_lints/src/methods/unnecessary_to_owned.rs b/clippy_lints/src/methods/unnecessary_to_owned.rs index 50d6f3b7e55..78d4bae60e5 100644 --- a/clippy_lints/src/methods/unnecessary_to_owned.rs +++ b/clippy_lints/src/methods/unnecessary_to_owned.rs @@ -1,7 +1,7 @@ use super::implicit_clone::is_clone_like; use super::unnecessary_iter_cloned::{self, is_into_iter}; +use clippy_config::msrvs::{self, Msrv}; use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::msrvs::{self, Msrv}; use clippy_utils::source::snippet_opt; use clippy_utils::ty::{get_iterator_item_ty, implements_trait, is_copy, peel_mid_ty_refs}; use clippy_utils::visitors::find_all_ret_expressions; diff --git a/clippy_lints/src/methods/waker_clone_wake.rs b/clippy_lints/src/methods/waker_clone_wake.rs new file mode 100644 index 00000000000..da66632d55f --- /dev/null +++ b/clippy_lints/src/methods/waker_clone_wake.rs @@ -0,0 +1,32 @@ +use clippy_utils::diagnostics::span_lint_and_sugg; +use clippy_utils::source::snippet_with_applicability; +use clippy_utils::{is_trait_method, match_def_path, paths}; +use rustc_errors::Applicability; +use rustc_hir::{Expr, ExprKind}; +use rustc_lint::LateContext; +use rustc_span::sym; + +use super::WAKER_CLONE_WAKE; + +pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, recv: &'tcx Expr<'_>) { + let ty = cx.typeck_results().expr_ty(recv); + + if let Some(did) = ty.ty_adt_def() + && match_def_path(cx, did.did(), &paths::WAKER) + && let ExprKind::MethodCall(_, waker_ref, &[], _) = recv.kind + && is_trait_method(cx, recv, sym::Clone) + { + let mut applicability = Applicability::MachineApplicable; + let snippet = snippet_with_applicability(cx, waker_ref.span.source_callsite(), "..", &mut applicability); + + span_lint_and_sugg( + cx, + WAKER_CLONE_WAKE, + expr.span, + "cloning a `Waker` only to wake it", + "replace with", + format!("{snippet}.wake_by_ref()"), + applicability, + ); + } +} |