From f7aef635c14c70b59b7d0b53c05ef5e8a4dae401 Mon Sep 17 00:00:00 2001 From: Alex Macleod Date: Thu, 18 Apr 2024 17:05:07 +0000 Subject: [PATCH] Rework interior mutability detection --- book/src/lint_configuration.md | 5 +- clippy_config/src/conf.rs | 5 +- clippy_lints/src/copies.rs | 44 +++---- clippy_lints/src/mut_key.rs | 67 +++------- clippy_lints/src/non_copy_const.rs | 99 +++++--------- clippy_lints/src/trait_bounds.rs | 1 + clippy_utils/src/lib.rs | 6 +- clippy_utils/src/ty.rs | 124 ++++++++++++------ tests/ui-toml/mut_key/mut_key.rs | 8 ++ .../borrow_interior_mutable_const/traits.rs | 4 +- .../traits.stderr | 18 ++- .../declare_interior_mutable_const/traits.rs | 5 +- .../traits.stderr | 20 ++- tests/ui/mut_key.rs | 10 +- tests/ui/mut_key.stderr | 32 ++--- 15 files changed, 225 insertions(+), 223 deletions(-) diff --git a/book/src/lint_configuration.md b/book/src/lint_configuration.md index 7cefa6852..fe0e9b80b 100644 --- a/book/src/lint_configuration.md +++ b/book/src/lint_configuration.md @@ -506,13 +506,14 @@ The maximum byte size a `Future` can have, before it triggers the `clippy::large ## `ignore-interior-mutability` -A list of paths to types that should be treated like `Arc`, i.e. ignored but -for the generic parameters for determining interior mutability +A list of paths to types that should be treated as if they do not contain interior mutability **Default Value:** `["bytes::Bytes"]` --- **Affected lints:** +* [`borrow_interior_mutable_const`](https://rust-lang.github.io/rust-clippy/master/index.html#borrow_interior_mutable_const) +* [`declare_interior_mutable_const`](https://rust-lang.github.io/rust-clippy/master/index.html#declare_interior_mutable_const) * [`ifs_same_cond`](https://rust-lang.github.io/rust-clippy/master/index.html#ifs_same_cond) * [`mutable_key_type`](https://rust-lang.github.io/rust-clippy/master/index.html#mutable_key_type) diff --git a/clippy_config/src/conf.rs b/clippy_config/src/conf.rs index 781282213..bbce4180d 100644 --- a/clippy_config/src/conf.rs +++ b/clippy_config/src/conf.rs @@ -467,10 +467,9 @@ define_Conf! { /// /// The maximum size of the `Err`-variant in a `Result` returned from a function (large_error_threshold: u64 = 128), - /// Lint: MUTABLE_KEY_TYPE, IFS_SAME_COND. + /// Lint: MUTABLE_KEY_TYPE, IFS_SAME_COND, BORROW_INTERIOR_MUTABLE_CONST, DECLARE_INTERIOR_MUTABLE_CONST. /// - /// A list of paths to types that should be treated like `Arc`, i.e. ignored but - /// for the generic parameters for determining interior mutability + /// A list of paths to types that should be treated as if they do not contain interior mutability (ignore_interior_mutability: Vec = Vec::from(["bytes::Bytes".into()])), /// Lint: UNINLINED_FORMAT_ARGS. /// diff --git a/clippy_lints/src/copies.rs b/clippy_lints/src/copies.rs index acdcb54be..ccf1d9d6f 100644 --- a/clippy_lints/src/copies.rs +++ b/clippy_lints/src/copies.rs @@ -1,15 +1,14 @@ use clippy_utils::diagnostics::{span_lint_and_note, span_lint_and_then}; use clippy_utils::source::{first_line_of_span, indent_of, reindent_multiline, snippet, snippet_opt}; -use clippy_utils::ty::{is_interior_mut_ty, needs_ordered_drop}; +use clippy_utils::ty::{needs_ordered_drop, InteriorMut}; use clippy_utils::visitors::for_each_expr; use clippy_utils::{ - capture_local_usage, def_path_def_ids, eq_expr_value, find_binding_init, get_enclosing_block, hash_expr, hash_stmt, - if_sequence, is_else_clause, is_lint_allowed, path_to_local, search_same, ContainsName, HirEqInterExpr, SpanlessEq, + capture_local_usage, eq_expr_value, find_binding_init, get_enclosing_block, hash_expr, hash_stmt, if_sequence, + is_else_clause, is_lint_allowed, path_to_local, search_same, ContainsName, HirEqInterExpr, SpanlessEq, }; use core::iter; use core::ops::ControlFlow; use rustc_errors::Applicability; -use rustc_hir::def_id::DefIdSet; use rustc_hir::{intravisit, BinOpKind, Block, Expr, ExprKind, HirId, HirIdSet, Stmt, StmtKind}; use rustc_lint::{LateContext, LateLintPass}; use rustc_session::impl_lint_pass; @@ -159,40 +158,36 @@ declare_clippy_lint! { "`if` statement with shared code in all blocks" } -pub struct CopyAndPaste { +pub struct CopyAndPaste<'tcx> { ignore_interior_mutability: Vec, - ignored_ty_ids: DefIdSet, + interior_mut: InteriorMut<'tcx>, } -impl CopyAndPaste { +impl CopyAndPaste<'_> { pub fn new(ignore_interior_mutability: Vec) -> Self { Self { ignore_interior_mutability, - ignored_ty_ids: DefIdSet::new(), + interior_mut: InteriorMut::default(), } } } -impl_lint_pass!(CopyAndPaste => [ +impl_lint_pass!(CopyAndPaste<'_> => [ IFS_SAME_COND, SAME_FUNCTIONS_IN_IF_CONDITION, IF_SAME_THEN_ELSE, BRANCHES_SHARING_CODE ]); -impl<'tcx> LateLintPass<'tcx> for CopyAndPaste { +impl<'tcx> LateLintPass<'tcx> for CopyAndPaste<'tcx> { fn check_crate(&mut self, cx: &LateContext<'tcx>) { - for ignored_ty in &self.ignore_interior_mutability { - let path: Vec<&str> = ignored_ty.split("::").collect(); - for id in def_path_def_ids(cx, path.as_slice()) { - self.ignored_ty_ids.insert(id); - } - } + self.interior_mut = InteriorMut::new(cx, &self.ignore_interior_mutability); } + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { if !expr.span.from_expansion() && matches!(expr.kind, ExprKind::If(..)) && !is_else_clause(cx.tcx, expr) { let (conds, blocks) = if_sequence(expr); - lint_same_cond(cx, &conds, &self.ignored_ty_ids); + lint_same_cond(cx, &conds, &mut self.interior_mut); lint_same_fns_in_if_cond(cx, &conds); let all_same = !is_lint_allowed(cx, IF_SAME_THEN_ELSE, expr.hir_id) && lint_if_same_then_else(cx, &conds, &blocks); @@ -570,13 +565,14 @@ fn check_for_warn_of_moved_symbol(cx: &LateContext<'_>, symbols: &[(HirId, Symbo }) } -fn method_caller_is_mutable(cx: &LateContext<'_>, caller_expr: &Expr<'_>, ignored_ty_ids: &DefIdSet) -> bool { +fn method_caller_is_mutable<'tcx>( + cx: &LateContext<'tcx>, + caller_expr: &Expr<'_>, + interior_mut: &mut InteriorMut<'tcx>, +) -> bool { let caller_ty = cx.typeck_results().expr_ty(caller_expr); - // Check if given type has inner mutability and was not set to ignored by the configuration - let is_inner_mut_ty = is_interior_mut_ty(cx, caller_ty) - && !matches!(caller_ty.ty_adt_def(), Some(adt) if ignored_ty_ids.contains(&adt.did())); - is_inner_mut_ty + interior_mut.is_interior_mut_ty(cx, caller_ty) || caller_ty.is_mutable_ptr() // `find_binding_init` will return the binding iff its not mutable || path_to_local(caller_expr) @@ -585,7 +581,7 @@ fn method_caller_is_mutable(cx: &LateContext<'_>, caller_expr: &Expr<'_>, ignore } /// Implementation of `IFS_SAME_COND`. -fn lint_same_cond(cx: &LateContext<'_>, conds: &[&Expr<'_>], ignored_ty_ids: &DefIdSet) { +fn lint_same_cond<'tcx>(cx: &LateContext<'tcx>, conds: &[&Expr<'_>], interior_mut: &mut InteriorMut<'tcx>) { for (i, j) in search_same( conds, |e| hash_expr(cx, e), @@ -593,7 +589,7 @@ fn lint_same_cond(cx: &LateContext<'_>, conds: &[&Expr<'_>], ignored_ty_ids: &De // Ignore eq_expr side effects iff one of the expression kind is a method call // and the caller is not a mutable, including inner mutable type. if let ExprKind::MethodCall(_, caller, _, _) = lhs.kind { - if method_caller_is_mutable(cx, caller, ignored_ty_ids) { + if method_caller_is_mutable(cx, caller, interior_mut) { false } else { SpanlessEq::new(cx).eq_expr(lhs, rhs) diff --git a/clippy_lints/src/mut_key.rs b/clippy_lints/src/mut_key.rs index 8c2f43c97..2eb534da0 100644 --- a/clippy_lints/src/mut_key.rs +++ b/clippy_lints/src/mut_key.rs @@ -1,7 +1,6 @@ use clippy_utils::diagnostics::span_lint; -use clippy_utils::ty::is_interior_mut_ty; -use clippy_utils::{def_path_def_ids, trait_ref_of_method}; -use rustc_data_structures::fx::FxHashSet; +use clippy_utils::trait_ref_of_method; +use clippy_utils::ty::InteriorMut; use rustc_hir as hir; use rustc_lint::{LateContext, LateLintPass}; use rustc_middle::ty::{self, Ty}; @@ -23,27 +22,15 @@ declare_clippy_lint! { /// ### Known problems /// /// #### False Positives - /// It's correct to use a struct that contains interior mutability as a key, when its + /// It's correct to use a struct that contains interior mutability as a key when its /// implementation of `Hash` or `Ord` doesn't access any of the interior mutable types. /// However, this lint is unable to recognize this, so it will often cause false positives in - /// theses cases. The `bytes` crate is a great example of this. + /// these cases. /// /// #### False Negatives - /// For custom `struct`s/`enum`s, this lint is unable to check for interior mutability behind - /// indirection. For example, `struct BadKey<'a>(&'a Cell)` will be seen as immutable - /// and cause a false negative if its implementation of `Hash`/`Ord` accesses the `Cell`. - /// - /// This lint does check a few cases for indirection. Firstly, using some standard library - /// types (`Option`, `Result`, `Box`, `Rc`, `Arc`, `Vec`, `VecDeque`, `BTreeMap` and - /// `BTreeSet`) directly as keys (e.g. in `HashMap>, ()>`) **will** trigger the - /// lint, because the impls of `Hash`/`Ord` for these types directly call `Hash`/`Ord` on their - /// contained type. - /// - /// Secondly, the implementations of `Hash` and `Ord` for raw pointers (`*const T` or `*mut T`) - /// apply only to the **address** of the contained value. Therefore, interior mutability - /// behind raw pointers (e.g. in `HashSet<*mut Cell>`) can't impact the value of `Hash` - /// or `Ord`, and therefore will not trigger this link. For more info, see issue - /// [#6745](https://github.com/rust-lang/rust-clippy/issues/6745). + /// This lint does not follow raw pointers (`*const T` or `*mut T`) as `Hash` and `Ord` + /// apply only to the **address** of the contained value. This can cause false negatives for + /// custom collections that use raw pointers internally. /// /// ### Example /// ```no_run @@ -51,13 +38,12 @@ declare_clippy_lint! { /// use std::collections::HashSet; /// use std::hash::{Hash, Hasher}; /// use std::sync::atomic::AtomicUsize; - ///# #[allow(unused)] /// /// struct Bad(AtomicUsize); /// impl PartialEq for Bad { /// fn eq(&self, rhs: &Self) -> bool { /// .. - /// ; unimplemented!(); + /// # ; true /// } /// } /// @@ -66,7 +52,7 @@ declare_clippy_lint! { /// impl Hash for Bad { /// fn hash(&self, h: &mut H) { /// .. - /// ; unimplemented!(); + /// # ; /// } /// } /// @@ -80,25 +66,16 @@ declare_clippy_lint! { "Check for mutable `Map`/`Set` key type" } -#[derive(Clone)] -pub struct MutableKeyType { +pub struct MutableKeyType<'tcx> { ignore_interior_mutability: Vec, - ignore_mut_def_ids: FxHashSet, + interior_mut: InteriorMut<'tcx>, } -impl_lint_pass!(MutableKeyType => [ MUTABLE_KEY_TYPE ]); +impl_lint_pass!(MutableKeyType<'_> => [ MUTABLE_KEY_TYPE ]); -impl<'tcx> LateLintPass<'tcx> for MutableKeyType { +impl<'tcx> LateLintPass<'tcx> for MutableKeyType<'tcx> { fn check_crate(&mut self, cx: &LateContext<'tcx>) { - self.ignore_mut_def_ids.clear(); - let mut path = Vec::new(); - for ty in &self.ignore_interior_mutability { - path.extend(ty.split("::")); - for id in def_path_def_ids(cx, &path[..]) { - self.ignore_mut_def_ids.insert(id); - } - path.clear(); - } + self.interior_mut = InteriorMut::without_pointers(cx, &self.ignore_interior_mutability); } fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) { @@ -121,7 +98,7 @@ impl<'tcx> LateLintPass<'tcx> for MutableKeyType { } } - fn check_local(&mut self, cx: &LateContext<'_>, local: &hir::LetStmt<'_>) { + fn check_local(&mut self, cx: &LateContext<'tcx>, local: &hir::LetStmt<'tcx>) { if let hir::PatKind::Wild = local.pat.kind { return; } @@ -129,15 +106,15 @@ impl<'tcx> LateLintPass<'tcx> for MutableKeyType { } } -impl MutableKeyType { +impl<'tcx> MutableKeyType<'tcx> { pub fn new(ignore_interior_mutability: Vec) -> Self { Self { ignore_interior_mutability, - ignore_mut_def_ids: FxHashSet::default(), + interior_mut: InteriorMut::default(), } } - fn check_sig(&self, cx: &LateContext<'_>, fn_def_id: LocalDefId, decl: &hir::FnDecl<'_>) { + fn check_sig(&mut self, cx: &LateContext<'tcx>, fn_def_id: LocalDefId, decl: &hir::FnDecl<'tcx>) { let fn_sig = cx.tcx.fn_sig(fn_def_id).instantiate_identity(); for (hir_ty, ty) in iter::zip(decl.inputs, fn_sig.inputs().skip_binder()) { self.check_ty_(cx, hir_ty.span, *ty); @@ -151,7 +128,7 @@ impl MutableKeyType { // We want to lint 1. sets or maps with 2. not immutable key types and 3. no unerased // generics (because the compiler cannot ensure immutability for unknown types). - fn check_ty_<'tcx>(&self, cx: &LateContext<'tcx>, span: Span, ty: Ty<'tcx>) { + fn check_ty_(&mut self, cx: &LateContext<'tcx>, span: Span, ty: Ty<'tcx>) { let ty = ty.peel_refs(); if let ty::Adt(def, args) = ty.kind() { let is_keyed_type = [sym::HashMap, sym::BTreeMap, sym::HashSet, sym::BTreeSet] @@ -162,11 +139,7 @@ impl MutableKeyType { } let subst_ty = args.type_at(0); - // Determines if a type contains interior mutability which would affect its implementation of - // [`Hash`] or [`Ord`]. - if is_interior_mut_ty(cx, subst_ty) - && !matches!(subst_ty.ty_adt_def(), Some(adt) if self.ignore_mut_def_ids.contains(&adt.did())) - { + if self.interior_mut.is_interior_mut_ty(cx, subst_ty) { span_lint(cx, MUTABLE_KEY_TYPE, span, "mutable key type"); } } diff --git a/clippy_lints/src/non_copy_const.rs b/clippy_lints/src/non_copy_const.rs index ff10a841a..76d9cee18 100644 --- a/clippy_lints/src/non_copy_const.rs +++ b/clippy_lints/src/non_copy_const.rs @@ -5,9 +5,9 @@ use std::ptr; use clippy_utils::diagnostics::span_lint_and_then; +use clippy_utils::in_constant; use clippy_utils::macros::macro_backtrace; -use clippy_utils::{def_path_def_ids, in_constant}; -use rustc_data_structures::fx::FxHashSet; +use clippy_utils::ty::InteriorMut; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::DefId; use rustc_hir::{ @@ -52,8 +52,8 @@ declare_clippy_lint! { /// There're other enums plus associated constants cases that the lint cannot handle. /// /// Types that have underlying or potential interior mutability trigger the lint whether - /// the interior mutable field is used or not. See issues - /// [#5812](https://github.com/rust-lang/rust-clippy/issues/5812) and + /// the interior mutable field is used or not. See issue + /// [#5812](https://github.com/rust-lang/rust-clippy/issues/5812) /// /// ### Example /// ```no_run @@ -170,42 +170,22 @@ fn lint(cx: &LateContext<'_>, source: Source) { }); } -#[derive(Clone)] -pub struct NonCopyConst { +pub struct NonCopyConst<'tcx> { ignore_interior_mutability: Vec, - ignore_mut_def_ids: FxHashSet, + interior_mut: InteriorMut<'tcx>, } -impl_lint_pass!(NonCopyConst => [DECLARE_INTERIOR_MUTABLE_CONST, BORROW_INTERIOR_MUTABLE_CONST]); +impl_lint_pass!(NonCopyConst<'_> => [DECLARE_INTERIOR_MUTABLE_CONST, BORROW_INTERIOR_MUTABLE_CONST]); -impl NonCopyConst { +impl<'tcx> NonCopyConst<'tcx> { pub fn new(ignore_interior_mutability: Vec) -> Self { Self { ignore_interior_mutability, - ignore_mut_def_ids: FxHashSet::default(), + interior_mut: InteriorMut::default(), } } - fn is_ty_ignored(&self, ty: Ty<'_>) -> bool { - matches!(ty.ty_adt_def(), Some(adt) if self.ignore_mut_def_ids.contains(&adt.did())) - } - - fn is_unfrozen<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool { - // Ignore types whose layout is unknown since `is_freeze` reports every generic types as `!Freeze`, - // making it indistinguishable from `UnsafeCell`. i.e. it isn't a tool to prove a type is - // 'unfrozen'. However, this code causes a false negative in which - // a type contains a layout-unknown type, but also an unsafe cell like `const CELL: Cell`. - // Yet, it's better than `ty.has_type_flags(TypeFlags::HAS_TY_PARAM | TypeFlags::HAS_PROJECTION)` - // since it works when a pointer indirection involves (`Cell<*const T>`). - // Making up a `ParamEnv` where every generic params and assoc types are `Freeze`is another option; - // but I'm not sure whether it's a decent way, if possible. - cx.tcx.layout_of(cx.param_env.and(ty)).is_ok() && !ty.is_freeze(cx.tcx, cx.param_env) - } - - fn is_value_unfrozen_raw_inner<'tcx>(&self, cx: &LateContext<'tcx>, val: ty::ValTree<'tcx>, ty: Ty<'tcx>) -> bool { - if self.is_ty_ignored(ty) { - return false; - } + fn is_value_unfrozen_raw_inner(cx: &LateContext<'tcx>, val: ty::ValTree<'tcx>, ty: Ty<'tcx>) -> bool { match *ty.kind() { // the fact that we have to dig into every structs to search enums // leads us to the point checking `UnsafeCell` directly is the only option. @@ -216,8 +196,7 @@ impl NonCopyConst { ty::Array(ty, _) => val .unwrap_branch() .iter() - .any(|field| self.is_value_unfrozen_raw_inner(cx, *field, ty)), - ty::Adt(def, _) if def.is_union() => false, + .any(|field| Self::is_value_unfrozen_raw_inner(cx, *field, ty)), ty::Adt(def, args) if def.is_enum() => { let (&variant_index, fields) = val.unwrap_branch().split_first().unwrap(); let variant_index = VariantIdx::from_u32(variant_index.unwrap_leaf().try_to_u32().ok().unwrap()); @@ -230,24 +209,23 @@ impl NonCopyConst { .iter() .map(|field| field.ty(cx.tcx, args)), ) - .any(|(field, ty)| self.is_value_unfrozen_raw_inner(cx, field, ty)) + .any(|(field, ty)| Self::is_value_unfrozen_raw_inner(cx, field, ty)) }, ty::Adt(def, args) => val .unwrap_branch() .iter() .zip(def.non_enum_variant().fields.iter().map(|field| field.ty(cx.tcx, args))) - .any(|(field, ty)| self.is_value_unfrozen_raw_inner(cx, *field, ty)), + .any(|(field, ty)| Self::is_value_unfrozen_raw_inner(cx, *field, ty)), ty::Tuple(tys) => val .unwrap_branch() .iter() .zip(tys) - .any(|(field, ty)| self.is_value_unfrozen_raw_inner(cx, *field, ty)), + .any(|(field, ty)| Self::is_value_unfrozen_raw_inner(cx, *field, ty)), _ => false, } } - fn is_value_unfrozen_raw<'tcx>( - &self, + fn is_value_unfrozen_raw( cx: &LateContext<'tcx>, result: Result>, ErrorHandled>, ty: Ty<'tcx>, @@ -277,11 +255,11 @@ impl NonCopyConst { // I chose this way because unfrozen enums as assoc consts are rare (or, hopefully, none). matches!(err, ErrorHandled::TooGeneric(..)) }, - |val| val.map_or(true, |val| self.is_value_unfrozen_raw_inner(cx, val, ty)), + |val| val.map_or(true, |val| Self::is_value_unfrozen_raw_inner(cx, val, ty)), ) } - fn is_value_unfrozen_poly<'tcx>(&self, cx: &LateContext<'tcx>, body_id: BodyId, ty: Ty<'tcx>) -> bool { + fn is_value_unfrozen_poly(cx: &LateContext<'tcx>, body_id: BodyId, ty: Ty<'tcx>) -> bool { let def_id = body_id.hir_id.owner.to_def_id(); let args = ty::GenericArgs::identity_for_item(cx.tcx, def_id); let instance = ty::Instance::new(def_id, args); @@ -291,17 +269,17 @@ impl NonCopyConst { }; let param_env = cx.tcx.param_env(def_id).with_reveal_all_normalized(cx.tcx); let result = cx.tcx.const_eval_global_id_for_typeck(param_env, cid, DUMMY_SP); - self.is_value_unfrozen_raw(cx, result, ty) + Self::is_value_unfrozen_raw(cx, result, ty) } - fn is_value_unfrozen_expr<'tcx>(&self, cx: &LateContext<'tcx>, hir_id: HirId, def_id: DefId, ty: Ty<'tcx>) -> bool { + fn is_value_unfrozen_expr(cx: &LateContext<'tcx>, hir_id: HirId, def_id: DefId, ty: Ty<'tcx>) -> bool { let args = cx.typeck_results().node_args(hir_id); let result = Self::const_eval_resolve(cx.tcx, cx.param_env, ty::UnevaluatedConst::new(def_id, args), DUMMY_SP); - self.is_value_unfrozen_raw(cx, result, ty) + Self::is_value_unfrozen_raw(cx, result, ty) } - pub fn const_eval_resolve<'tcx>( + pub fn const_eval_resolve( tcx: TyCtxt<'tcx>, param_env: ty::ParamEnv<'tcx>, ct: ty::UnevaluatedConst<'tcx>, @@ -321,26 +299,17 @@ impl NonCopyConst { } } -impl<'tcx> LateLintPass<'tcx> for NonCopyConst { +impl<'tcx> LateLintPass<'tcx> for NonCopyConst<'tcx> { fn check_crate(&mut self, cx: &LateContext<'tcx>) { - self.ignore_mut_def_ids.clear(); - let mut path = Vec::new(); - for ty in &self.ignore_interior_mutability { - path.extend(ty.split("::")); - for id in def_path_def_ids(cx, &path[..]) { - self.ignore_mut_def_ids.insert(id); - } - path.clear(); - } + self.interior_mut = InteriorMut::new(cx, &self.ignore_interior_mutability); } fn check_item(&mut self, cx: &LateContext<'tcx>, it: &'tcx Item<'_>) { if let ItemKind::Const(.., body_id) = it.kind { let ty = cx.tcx.type_of(it.owner_id).instantiate_identity(); if !ignored_macro(cx, it) - && !self.is_ty_ignored(ty) - && Self::is_unfrozen(cx, ty) - && self.is_value_unfrozen_poly(cx, body_id, ty) + && self.interior_mut.is_interior_mut_ty(cx, ty) + && Self::is_value_unfrozen_poly(cx, body_id, ty) { lint(cx, Source::Item { item: it.span }); } @@ -354,7 +323,7 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst { // Normalize assoc types because ones originated from generic params // bounded other traits could have their bound. let normalized = cx.tcx.normalize_erasing_regions(cx.param_env, ty); - if !self.is_ty_ignored(ty) && Self::is_unfrozen(cx, normalized) + if self.interior_mut.is_interior_mut_ty(cx, normalized) // When there's no default value, lint it only according to its type; // in other words, lint consts whose value *could* be unfrozen, not definitely is. // This feels inconsistent with how the lint treats generic types, @@ -367,7 +336,7 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst { // i.e. having an enum doesn't necessary mean a type has a frozen variant. // And, implementing it isn't a trivial task; it'll probably end up // re-implementing the trait predicate evaluation specific to `Freeze`. - && body_id_opt.map_or(true, |body_id| self.is_value_unfrozen_poly(cx, body_id, normalized)) + && body_id_opt.map_or(true, |body_id| Self::is_value_unfrozen_poly(cx, body_id, normalized)) { lint(cx, Source::Assoc { item: trait_item.span }); } @@ -409,8 +378,8 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst { // e.g. `layout_of(...).is_err() || has_frozen_variant(...);` && let ty = cx.tcx.type_of(impl_item.owner_id).instantiate_identity() && let normalized = cx.tcx.normalize_erasing_regions(cx.param_env, ty) - && !self.is_ty_ignored(ty) && Self::is_unfrozen(cx, normalized) - && self.is_value_unfrozen_poly(cx, *body_id, normalized) + && self.interior_mut.is_interior_mut_ty(cx, normalized) + && Self::is_value_unfrozen_poly(cx, *body_id, normalized) { lint(cx, Source::Assoc { item: impl_item.span }); } @@ -420,9 +389,8 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst { // Normalize assoc types originated from generic params. let normalized = cx.tcx.normalize_erasing_regions(cx.param_env, ty); - if !self.is_ty_ignored(ty) - && Self::is_unfrozen(cx, ty) - && self.is_value_unfrozen_poly(cx, *body_id, normalized) + if self.interior_mut.is_interior_mut_ty(cx, normalized) + && Self::is_value_unfrozen_poly(cx, *body_id, normalized) { lint(cx, Source::Assoc { item: impl_item.span }); } @@ -517,9 +485,8 @@ impl<'tcx> LateLintPass<'tcx> for NonCopyConst { cx.typeck_results().expr_ty(dereferenced_expr) }; - if !self.is_ty_ignored(ty) - && Self::is_unfrozen(cx, ty) - && self.is_value_unfrozen_expr(cx, expr.hir_id, item_def_id, ty) + if self.interior_mut.is_interior_mut_ty(cx, ty) + && Self::is_value_unfrozen_expr(cx, expr.hir_id, item_def_id, ty) { lint(cx, Source::Expr { expr: expr.span }); } diff --git a/clippy_lints/src/trait_bounds.rs b/clippy_lints/src/trait_bounds.rs index 9468d367a..c05cd9ed5 100644 --- a/clippy_lints/src/trait_bounds.rs +++ b/clippy_lints/src/trait_bounds.rs @@ -237,6 +237,7 @@ impl TraitBounds { } } + #[allow(clippy::mutable_key_type)] fn check_type_repetition<'tcx>(&self, cx: &LateContext<'tcx>, gen: &'tcx Generics<'_>) { struct SpanlessTy<'cx, 'tcx> { ty: &'tcx Ty<'tcx>, diff --git a/clippy_utils/src/lib.rs b/clippy_utils/src/lib.rs index a13885b02..196ccf9df 100644 --- a/clippy_utils/src/lib.rs +++ b/clippy_utils/src/lib.rs @@ -2328,10 +2328,10 @@ pub fn is_slice_of_primitives(cx: &LateContext<'_>, expr: &Expr<'_>) -> Option(exprs: &[T], hash: Hash, eq: Eq) -> Vec<(&T, &T)> +pub fn search_same(exprs: &[T], mut hash: Hash, mut eq: Eq) -> Vec<(&T, &T)> where - Hash: Fn(&T) -> u64, - Eq: Fn(&T, &T) -> bool, + Hash: FnMut(&T) -> u64, + Eq: FnMut(&T, &T) -> bool, { match exprs { [a, b] if eq(a, b) => return vec![(a, b)], diff --git a/clippy_utils/src/ty.rs b/clippy_utils/src/ty.rs index a06a82c56..23750ed4d 100644 --- a/clippy_utils/src/ty.rs +++ b/clippy_utils/src/ty.rs @@ -29,9 +29,10 @@ use rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt as _ use rustc_trait_selection::traits::query::normalize::QueryNormalizeExt; use rustc_trait_selection::traits::{Obligation, ObligationCause}; use std::assert_matches::debug_assert_matches; +use std::collections::hash_map::Entry; use std::iter; -use crate::{match_def_path, path_res}; +use crate::{def_path_def_ids, match_def_path, path_res}; mod type_certainty; pub use type_certainty::expr_type_is_certain; @@ -1198,47 +1199,88 @@ pub fn make_normalized_projection<'tcx>( helper(tcx, param_env, make_projection(tcx, container_id, assoc_ty, args)?) } -/// Check if given type has inner mutability such as [`std::cell::Cell`] or [`std::cell::RefCell`] -/// etc. -pub fn is_interior_mut_ty<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool { - match *ty.kind() { - ty::Ref(_, inner_ty, mutbl) => mutbl == Mutability::Mut || is_interior_mut_ty(cx, inner_ty), - ty::Slice(inner_ty) => is_interior_mut_ty(cx, inner_ty), - ty::Array(inner_ty, size) => { - size.try_eval_target_usize(cx.tcx, cx.param_env) - .map_or(true, |u| u != 0) - && is_interior_mut_ty(cx, inner_ty) - }, - ty::Tuple(fields) => fields.iter().any(|ty| is_interior_mut_ty(cx, ty)), - ty::Adt(def, args) => { - // Special case for collections in `std` who's impl of `Hash` or `Ord` delegates to - // that of their type parameters. Note: we don't include `HashSet` and `HashMap` - // because they have no impl for `Hash` or `Ord`. - let def_id = def.did(); - let is_std_collection = [ - sym::Option, - sym::Result, - sym::LinkedList, - sym::Vec, - sym::VecDeque, - sym::BTreeMap, - sym::BTreeSet, - sym::Rc, - sym::Arc, - ] +/// Helper to check if given type has inner mutability such as [`std::cell::Cell`] or +/// [`std::cell::RefCell`]. +#[derive(Default, Debug)] +pub struct InteriorMut<'tcx> { + ignored_def_ids: FxHashSet, + ignore_pointers: bool, + tys: FxHashMap, Option>, +} + +impl<'tcx> InteriorMut<'tcx> { + pub fn new(cx: &LateContext<'tcx>, ignore_interior_mutability: &[String]) -> Self { + let ignored_def_ids = ignore_interior_mutability .iter() - .any(|diag_item| cx.tcx.is_diagnostic_item(*diag_item, def_id)); - let is_box = Some(def_id) == cx.tcx.lang_items().owned_box(); - if is_std_collection || is_box { - // The type is mutable if any of its type parameters are - args.types().any(|ty| is_interior_mut_ty(cx, ty)) - } else { - !ty.has_escaping_bound_vars() - && cx.tcx.layout_of(cx.param_env.and(ty)).is_ok() - && !ty.is_freeze(cx.tcx, cx.param_env) - } - }, - _ => false, + .flat_map(|ignored_ty| { + let path: Vec<&str> = ignored_ty.split("::").collect(); + def_path_def_ids(cx, path.as_slice()) + }) + .collect(); + + Self { + ignored_def_ids, + ..Self::default() + } + } + + pub fn without_pointers(cx: &LateContext<'tcx>, ignore_interior_mutability: &[String]) -> Self { + Self { + ignore_pointers: true, + ..Self::new(cx, ignore_interior_mutability) + } + } + + /// Check if given type has inner mutability such as [`std::cell::Cell`] or + /// [`std::cell::RefCell`] etc. + pub fn is_interior_mut_ty(&mut self, cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool { + match self.tys.entry(ty) { + Entry::Occupied(o) => return *o.get() == Some(true), + // Temporarily insert a `None` to break cycles + Entry::Vacant(v) => v.insert(None), + }; + + let interior_mut = match *ty.kind() { + ty::RawPtr(inner_ty, _) if !self.ignore_pointers => self.is_interior_mut_ty(cx, inner_ty), + ty::Ref(_, inner_ty, _) | ty::Slice(inner_ty) => self.is_interior_mut_ty(cx, inner_ty), + ty::Array(inner_ty, size) => { + size.try_eval_target_usize(cx.tcx, cx.param_env) + .map_or(true, |u| u != 0) + && self.is_interior_mut_ty(cx, inner_ty) + }, + ty::Tuple(fields) => fields.iter().any(|ty| self.is_interior_mut_ty(cx, ty)), + ty::Adt(def, _) if def.is_unsafe_cell() => true, + ty::Adt(def, args) => { + let is_std_collection = matches!( + cx.tcx.get_diagnostic_name(def.did()), + Some( + sym::LinkedList + | sym::Vec + | sym::VecDeque + | sym::BTreeMap + | sym::BTreeSet + | sym::HashMap + | sym::HashSet + | sym::Arc + | sym::Rc + ) + ); + + if is_std_collection || def.is_box() { + // Include the types from std collections that are behind pointers internally + args.types().any(|ty| self.is_interior_mut_ty(cx, ty)) + } else if self.ignored_def_ids.contains(&def.did()) || def.is_phantom_data() { + false + } else { + def.all_fields() + .any(|f| self.is_interior_mut_ty(cx, f.ty(cx.tcx, args))) + } + }, + _ => false, + }; + + self.tys.insert(ty, Some(interior_mut)); + interior_mut } } diff --git a/tests/ui-toml/mut_key/mut_key.rs b/tests/ui-toml/mut_key/mut_key.rs index 095e0d154..3a8e3741e 100644 --- a/tests/ui-toml/mut_key/mut_key.rs +++ b/tests/ui-toml/mut_key/mut_key.rs @@ -44,10 +44,18 @@ impl Deref for Counted { } } +#[derive(Hash, PartialEq, Eq)] +struct ContainsCounted { + inner: Counted, +} + // This is not linted because `"mut_key::Counted"` is in // `arc_like_types` in `clippy.toml` fn should_not_take_this_arg(_v: HashSet>) {} +fn indirect(_: HashMap) {} + fn main() { should_not_take_this_arg(HashSet::new()); + indirect(HashMap::new()); } diff --git a/tests/ui/borrow_interior_mutable_const/traits.rs b/tests/ui/borrow_interior_mutable_const/traits.rs index 4da3833cb..5570e7cd6 100644 --- a/tests/ui/borrow_interior_mutable_const/traits.rs +++ b/tests/ui/borrow_interior_mutable_const/traits.rs @@ -158,7 +158,7 @@ trait BothOfCellAndGeneric { const INDIRECT: Cell<*const T>; fn function() { - let _ = &Self::DIRECT; + let _ = &Self::DIRECT; //~ ERROR: interior mutability let _ = &Self::INDIRECT; //~ ERROR: interior mutability } } @@ -168,7 +168,7 @@ impl BothOfCellAndGeneric for Vec { const INDIRECT: Cell<*const T> = Cell::new(std::ptr::null()); fn function() { - let _ = &Self::DIRECT; + let _ = &Self::DIRECT; //~ ERROR: interior mutability let _ = &Self::INDIRECT; //~ ERROR: interior mutability } } diff --git a/tests/ui/borrow_interior_mutable_const/traits.stderr b/tests/ui/borrow_interior_mutable_const/traits.stderr index 582b744b4..8602b46b0 100644 --- a/tests/ui/borrow_interior_mutable_const/traits.stderr +++ b/tests/ui/borrow_interior_mutable_const/traits.stderr @@ -75,6 +75,14 @@ LL | let _ = &Self::WRAPPED_SELF; | = help: assign this const to a local or static variable, and use the variable here +error: a `const` item with interior mutability should not be borrowed + --> tests/ui/borrow_interior_mutable_const/traits.rs:161:18 + | +LL | let _ = &Self::DIRECT; + | ^^^^^^^^^^^^ + | + = help: assign this const to a local or static variable, and use the variable here + error: a `const` item with interior mutability should not be borrowed --> tests/ui/borrow_interior_mutable_const/traits.rs:162:18 | @@ -83,6 +91,14 @@ LL | let _ = &Self::INDIRECT; | = help: assign this const to a local or static variable, and use the variable here +error: a `const` item with interior mutability should not be borrowed + --> tests/ui/borrow_interior_mutable_const/traits.rs:171:18 + | +LL | let _ = &Self::DIRECT; + | ^^^^^^^^^^^^ + | + = help: assign this const to a local or static variable, and use the variable here + error: a `const` item with interior mutability should not be borrowed --> tests/ui/borrow_interior_mutable_const/traits.rs:172:18 | @@ -123,5 +139,5 @@ LL | assert_eq!(u64::ATOMIC.load(Ordering::SeqCst), 9); | = help: assign this const to a local or static variable, and use the variable here -error: aborting due to 15 previous errors +error: aborting due to 17 previous errors diff --git a/tests/ui/declare_interior_mutable_const/traits.rs b/tests/ui/declare_interior_mutable_const/traits.rs index adc53891e..490073f97 100644 --- a/tests/ui/declare_interior_mutable_const/traits.rs +++ b/tests/ui/declare_interior_mutable_const/traits.rs @@ -121,13 +121,12 @@ impl SelfType for AtomicUsize { // Even though a constant contains a generic type, if it also have an interior mutable type, // it should be linted at the definition site. trait BothOfCellAndGeneric { - // this is a false negative in the current implementation. - const DIRECT: Cell; + const DIRECT: Cell; //~ ERROR: interior mutable const INDIRECT: Cell<*const T>; //~ ERROR: interior mutable } impl BothOfCellAndGeneric for u64 { - const DIRECT: Cell = Cell::new(T::DEFAULT); + const DIRECT: Cell = Cell::new(T::DEFAULT); //~ ERROR: interior mutable const INDIRECT: Cell<*const T> = Cell::new(std::ptr::null()); } diff --git a/tests/ui/declare_interior_mutable_const/traits.stderr b/tests/ui/declare_interior_mutable_const/traits.stderr index 328453efa..1d1e9e200 100644 --- a/tests/ui/declare_interior_mutable_const/traits.stderr +++ b/tests/ui/declare_interior_mutable_const/traits.stderr @@ -55,22 +55,34 @@ LL | const WRAPPED_SELF: Option = Some(AtomicUsize::new(21)); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: a `const` item should never be interior mutable - --> tests/ui/declare_interior_mutable_const/traits.rs:126:5 + --> tests/ui/declare_interior_mutable_const/traits.rs:124:5 + | +LL | const DIRECT: Cell; + | ^^^^^^^^^^^^^^^^^^^^^^ + +error: a `const` item should never be interior mutable + --> tests/ui/declare_interior_mutable_const/traits.rs:125:5 | LL | const INDIRECT: Cell<*const T>; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: a `const` item should never be interior mutable - --> tests/ui/declare_interior_mutable_const/traits.rs:142:5 + --> tests/ui/declare_interior_mutable_const/traits.rs:129:5 + | +LL | const DIRECT: Cell = Cell::new(T::DEFAULT); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: a `const` item should never be interior mutable + --> tests/ui/declare_interior_mutable_const/traits.rs:141:5 | LL | const ATOMIC: AtomicUsize = AtomicUsize::new(18); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: a `const` item should never be interior mutable - --> tests/ui/declare_interior_mutable_const/traits.rs:148:5 + --> tests/ui/declare_interior_mutable_const/traits.rs:147:5 | LL | const BOUNDED_ASSOC_TYPE: T::ToBeBounded = AtomicUsize::new(19); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -error: aborting due to 11 previous errors +error: aborting due to 13 previous errors diff --git a/tests/ui/mut_key.rs b/tests/ui/mut_key.rs index 2d70bfd4c..81d8732b3 100644 --- a/tests/ui/mut_key.rs +++ b/tests/ui/mut_key.rs @@ -5,7 +5,7 @@ use std::rc::Rc; use std::sync::atomic::AtomicUsize; use std::sync::atomic::Ordering::Relaxed; use std::sync::Arc; -//@no-rustfix + struct Key(AtomicUsize); impl Clone for Key { @@ -77,8 +77,6 @@ fn main() { //~^ ERROR: mutable key type let _map = HashMap::<&mut Cell, usize>::new(); //~^ ERROR: mutable key type - let _map = HashMap::<&mut usize, usize>::new(); - //~^ ERROR: mutable key type // Collection types from `std` who's impl of `Hash` or `Ord` delegate their type parameters let _map = HashMap::>, usize>::new(); //~^ ERROR: mutable key type @@ -92,8 +90,6 @@ fn main() { //~^ ERROR: mutable key type let _map = HashMap::>>, usize>::new(); //~^ ERROR: mutable key type - let _map = HashMap::, usize>::new(); - //~^ ERROR: mutable key type // Smart pointers from `std` who's impl of `Hash` or `Ord` delegate their type parameters let _map = HashMap::>, usize>::new(); //~^ ERROR: mutable key type @@ -101,4 +97,8 @@ fn main() { //~^ ERROR: mutable key type let _map = HashMap::>, usize>::new(); //~^ ERROR: mutable key type + + // Not interior mutability + let _map = HashMap::<&mut usize, usize>::new(); + let _map = HashMap::, usize>::new(); } diff --git a/tests/ui/mut_key.stderr b/tests/ui/mut_key.stderr index e54c3075d..5ad9aad2d 100644 --- a/tests/ui/mut_key.stderr +++ b/tests/ui/mut_key.stderr @@ -38,70 +38,58 @@ LL | let _map = HashMap::<&mut Cell, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:80:5 - | -LL | let _map = HashMap::<&mut usize, usize>::new(); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -error: mutable key type - --> tests/ui/mut_key.rs:83:5 + --> tests/ui/mut_key.rs:81:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:85:5 + --> tests/ui/mut_key.rs:83:5 | LL | let _map = HashMap::, ()>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:87:5 + --> tests/ui/mut_key.rs:85:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:89:5 + --> tests/ui/mut_key.rs:87:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:91:5 + --> tests/ui/mut_key.rs:89:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:93:5 + --> tests/ui/mut_key.rs:91:5 | LL | let _map = HashMap::>>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:95:5 - | -LL | let _map = HashMap::, usize>::new(); - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -error: mutable key type - --> tests/ui/mut_key.rs:98:5 + --> tests/ui/mut_key.rs:94:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:100:5 + --> tests/ui/mut_key.rs:96:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: mutable key type - --> tests/ui/mut_key.rs:102:5 + --> tests/ui/mut_key.rs:98:5 | LL | let _map = HashMap::>, usize>::new(); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -error: aborting due to 17 previous errors +error: aborting due to 15 previous errors