diff --git a/clippy_lints/src/matches/needless_match.rs b/clippy_lints/src/matches/needless_match.rs index b04db03f8d2e..3a2097c3df26 100644 --- a/clippy_lints/src/matches/needless_match.rs +++ b/clippy_lints/src/matches/needless_match.rs @@ -1,7 +1,7 @@ use super::NEEDLESS_MATCH; use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::source::snippet_with_applicability; -use clippy_utils::ty::{is_type_diagnostic_item, same_type_and_consts}; +use clippy_utils::ty::{is_type_diagnostic_item, same_type_modulo_regions}; use clippy_utils::{ SpanlessEq, eq_expr_value, get_parent_expr_for_hir, higher, is_else_clause, is_res_lang_ctor, over, path_res, peel_blocks_with_stmt, @@ -122,7 +122,7 @@ fn expr_ty_matches_p_ty(cx: &LateContext<'_>, expr: &Expr<'_>, p_expr: &Expr<'_> // Compare match_expr ty with local in `let local = match match_expr {..}` Node::LetStmt(local) => { let results = cx.typeck_results(); - return same_type_and_consts(results.node_type(local.hir_id), results.expr_ty(expr)); + return same_type_modulo_regions(results.node_type(local.hir_id), results.expr_ty(expr)); }, // compare match_expr ty with RetTy in `fn foo() -> RetTy` Node::Item(item) => { @@ -133,7 +133,7 @@ fn expr_ty_matches_p_ty(cx: &LateContext<'_>, expr: &Expr<'_>, p_expr: &Expr<'_> .instantiate_identity() .output() .skip_binder(); - return same_type_and_consts(output, cx.typeck_results().expr_ty(expr)); + return same_type_modulo_regions(output, cx.typeck_results().expr_ty(expr)); } }, // check the parent expr for this whole block `{ match match_expr {..} }` diff --git a/clippy_lints/src/operators/erasing_op.rs b/clippy_lints/src/operators/erasing_op.rs index e3fc8d8fea7d..8f5ee390f722 100644 --- a/clippy_lints/src/operators/erasing_op.rs +++ b/clippy_lints/src/operators/erasing_op.rs @@ -1,6 +1,6 @@ use clippy_utils::consts::{ConstEvalCtxt, Constant}; use clippy_utils::diagnostics::span_lint; -use clippy_utils::ty::same_type_and_consts; +use clippy_utils::ty::same_type_modulo_regions; use rustc_hir::{BinOpKind, Expr}; use rustc_lint::LateContext; @@ -29,7 +29,7 @@ pub(super) fn check<'tcx>( fn different_types(tck: &TypeckResults<'_>, input: &Expr<'_>, output: &Expr<'_>) -> bool { let input_ty = tck.expr_ty(input).peel_refs(); let output_ty = tck.expr_ty(output).peel_refs(); - !same_type_and_consts(input_ty, output_ty) + !same_type_modulo_regions(input_ty, output_ty) } fn check_op<'tcx>( diff --git a/clippy_lints/src/use_self.rs b/clippy_lints/src/use_self.rs index aeda864b7eb5..8210320591c6 100644 --- a/clippy_lints/src/use_self.rs +++ b/clippy_lints/src/use_self.rs @@ -2,20 +2,21 @@ use clippy_config::Conf; use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::is_from_proc_macro; use clippy_utils::msrvs::{self, Msrv}; -use clippy_utils::ty::{same_type_and_consts, ty_from_hir_ty}; +use clippy_utils::ty::{same_type_modulo_regions, ty_from_hir_ty}; use rustc_data_structures::fx::FxHashSet; use rustc_errors::Applicability; use rustc_hir::def::{CtorOf, DefKind, Res}; use rustc_hir::def_id::LocalDefId; use rustc_hir::intravisit::{InferKind, Visitor, VisitorExt, walk_ty}; use rustc_hir::{ - self as hir, AmbigArg, Expr, ExprKind, FnRetTy, FnSig, GenericArgsParentheses, GenericParam, GenericParamKind, - HirId, Impl, ImplItemKind, Item, ItemKind, Pat, PatExpr, PatExprKind, PatKind, Path, QPath, Ty, TyKind, + self as hir, AmbigArg, Expr, ExprKind, FnRetTy, FnSig, GenericArgsParentheses, GenericParamKind, HirId, Impl, + ImplItemKind, Item, ItemKind, Pat, PatExpr, PatExprKind, PatKind, Path, QPath, Ty, TyKind, }; use rustc_lint::{LateContext, LateLintPass}; use rustc_middle::ty::Ty as MiddleTy; use rustc_session::impl_lint_pass; use rustc_span::Span; +use std::iter; declare_clippy_lint! { /// ### What it does @@ -101,17 +102,11 @@ impl<'tcx> LateLintPass<'tcx> for UseSelf { let types_to_skip = generics .params .iter() - .filter_map(|param| match param { - GenericParam { - kind: - GenericParamKind::Const { - ty: Ty { hir_id, .. }, .. - }, - .. - } => Some(*hir_id), + .filter_map(|param| match param.kind { + GenericParamKind::Const { ty, .. } => Some(ty.hir_id), _ => None, }) - .chain(std::iter::once(self_ty.hir_id)) + .chain([self_ty.hir_id]) .collect(); StackItem::Check { impl_id: item.owner_id.def_id, @@ -210,11 +205,11 @@ impl<'tcx> LateLintPass<'tcx> for UseSelf { && !types_to_skip.contains(&hir_ty.hir_id) && let ty = ty_from_hir_ty(cx, hir_ty.as_unambig_ty()) && let impl_ty = cx.tcx.type_of(impl_id).instantiate_identity() - && same_type_and_consts(ty, impl_ty) + && same_type_modulo_regions(ty, impl_ty) // Ensure the type we encounter and the one from the impl have the same lifetime parameters. It may be that - // the lifetime parameters of `ty` are elided (`impl<'a> Foo<'a> { fn new() -> Self { Foo{..} } }`, in + // the lifetime parameters of `ty` are elided (`impl<'a> Foo<'a> { fn new() -> Self { Foo{..} } }`), in // which case we must still trigger the lint. - && (has_no_lifetime(ty) || same_lifetimes(ty, impl_ty)) + && same_lifetimes(ty, impl_ty) && self.msrv.meets(cx, msrvs::TYPE_ALIAS_ENUM_VARIANTS) { span_lint(cx, hir_ty.span); @@ -227,18 +222,16 @@ impl<'tcx> LateLintPass<'tcx> for UseSelf { && cx.typeck_results().expr_ty(expr) == cx.tcx.type_of(impl_id).instantiate_identity() && self.msrv.meets(cx, msrvs::TYPE_ALIAS_ENUM_VARIANTS) { - } else { - return; - } - match expr.kind { - ExprKind::Struct(QPath::Resolved(_, path), ..) => check_path(cx, path), - ExprKind::Call(fun, _) => { - if let ExprKind::Path(QPath::Resolved(_, path)) = fun.kind { - check_path(cx, path); - } - }, - ExprKind::Path(QPath::Resolved(_, path)) => check_path(cx, path), - _ => (), + match expr.kind { + ExprKind::Struct(QPath::Resolved(_, path), ..) => check_path(cx, path), + ExprKind::Call(fun, _) => { + if let ExprKind::Path(QPath::Resolved(_, path)) = fun.kind { + check_path(cx, path); + } + }, + ExprKind::Path(QPath::Resolved(_, path)) => check_path(cx, path), + _ => (), + } } } @@ -308,36 +301,20 @@ fn lint_path_to_variant(cx: &LateContext<'_>, path: &Path<'_>) { } } -/// Returns `true` if types `a` and `b` have the same lifetime parameters, otherwise returns -/// `false`. +/// Checks whether types `a` and `b` have the same lifetime parameters. /// /// This function does not check that types `a` and `b` are the same types. fn same_lifetimes<'tcx>(a: MiddleTy<'tcx>, b: MiddleTy<'tcx>) -> bool { use rustc_middle::ty::{Adt, GenericArgKind}; - match (&a.kind(), &b.kind()) { - (&Adt(_, args_a), &Adt(_, args_b)) => { - args_a - .iter() - .zip(args_b.iter()) - .all(|(arg_a, arg_b)| match (arg_a.kind(), arg_b.kind()) { - // TODO: Handle inferred lifetimes - (GenericArgKind::Lifetime(inner_a), GenericArgKind::Lifetime(inner_b)) => inner_a == inner_b, - (GenericArgKind::Type(type_a), GenericArgKind::Type(type_b)) => same_lifetimes(type_a, type_b), - _ => true, - }) + match (a.kind(), b.kind()) { + (Adt(_, args_a), Adt(_, args_b)) => { + iter::zip(*args_a, *args_b).all(|(arg_a, arg_b)| match (arg_a.kind(), arg_b.kind()) { + // TODO: Handle inferred lifetimes + (GenericArgKind::Lifetime(inner_a), GenericArgKind::Lifetime(inner_b)) => inner_a == inner_b, + (GenericArgKind::Type(type_a), GenericArgKind::Type(type_b)) => same_lifetimes(type_a, type_b), + _ => true, + }) }, _ => a == b, } } - -/// Returns `true` if `ty` has no lifetime parameter, otherwise returns `false`. -fn has_no_lifetime(ty: MiddleTy<'_>) -> bool { - use rustc_middle::ty::{Adt, GenericArgKind}; - match ty.kind() { - &Adt(_, args) => !args - .iter() - // TODO: Handle inferred lifetimes - .any(|arg| matches!(arg.kind(), GenericArgKind::Lifetime(..))), - _ => true, - } -} diff --git a/clippy_lints/src/useless_conversion.rs b/clippy_lints/src/useless_conversion.rs index 70ae982a4458..5274fdbd1dc2 100644 --- a/clippy_lints/src/useless_conversion.rs +++ b/clippy_lints/src/useless_conversion.rs @@ -1,7 +1,7 @@ use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_sugg, span_lint_and_then}; use clippy_utils::source::{snippet, snippet_with_context}; use clippy_utils::sugg::{DiagExt as _, Sugg}; -use clippy_utils::ty::{get_type_diagnostic_name, is_copy, is_type_diagnostic_item, same_type_and_consts}; +use clippy_utils::ty::{get_type_diagnostic_name, is_copy, is_type_diagnostic_item, same_type_modulo_regions}; use clippy_utils::{ get_parent_expr, is_inherent_method_call, is_trait_item, is_trait_method, is_ty_alias, path_to_local, sym, }; @@ -184,7 +184,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { && (is_trait_item(cx, arg, sym::Into) || is_trait_item(cx, arg, sym::From)) && let ty::FnDef(_, args) = cx.typeck_results().expr_ty(arg).kind() && let &[from_ty, to_ty] = args.into_type_list(cx.tcx).as_slice() - && same_type_and_consts(from_ty, to_ty) + && same_type_modulo_regions(from_ty, to_ty) { span_lint_and_then( cx, @@ -207,7 +207,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { if is_trait_method(cx, e, sym::Into) && name.ident.name == sym::into { let a = cx.typeck_results().expr_ty(e); let b = cx.typeck_results().expr_ty(recv); - if same_type_and_consts(a, b) { + if same_type_modulo_regions(a, b) { let mut app = Applicability::MachineApplicable; let sugg = snippet_with_context(cx, recv.span, e.span.ctxt(), "", &mut app).0; span_lint_and_sugg( @@ -324,7 +324,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { // If the types are identical then .into_iter() can be removed, unless the type // implements Copy, in which case .into_iter() returns a copy of the receiver and // cannot be safely omitted. - if same_type_and_consts(a, b) && !is_copy(cx, b) { + if same_type_modulo_regions(a, b) && !is_copy(cx, b) { // Below we check if the parent method call meets the following conditions: // 1. First parameter is `&mut self` (requires mutable reference) // 2. Second parameter implements the `FnMut` trait (e.g., Iterator::any) @@ -371,7 +371,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { && is_type_diagnostic_item(cx, a, sym::Result) && let ty::Adt(_, args) = a.kind() && let Some(a_type) = args.types().next() - && same_type_and_consts(a_type, b) + && same_type_modulo_regions(a_type, b) { span_lint_and_help( cx, @@ -396,7 +396,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { && is_type_diagnostic_item(cx, a, sym::Result) && let ty::Adt(_, args) = a.kind() && let Some(a_type) = args.types().next() - && same_type_and_consts(a_type, b) + && same_type_modulo_regions(a_type, b) { let hint = format!("consider removing `{}()`", snippet(cx, path.span, "TryFrom::try_from")); span_lint_and_help( @@ -407,7 +407,7 @@ impl<'tcx> LateLintPass<'tcx> for UselessConversion { None, hint, ); - } else if name == sym::from_fn && same_type_and_consts(a, b) { + } else if name == sym::from_fn && same_type_modulo_regions(a, b) { let mut app = Applicability::MachineApplicable; let sugg = Sugg::hir_with_context(cx, arg, e.span.ctxt(), "", &mut app).maybe_paren(); let sugg_msg = format!("consider removing `{}()`", snippet(cx, path.span, "From::from")); diff --git a/clippy_utils/src/ty/mod.rs b/clippy_utils/src/ty/mod.rs index 8e302f9d2ad1..8fbaac58288f 100644 --- a/clippy_utils/src/ty/mod.rs +++ b/clippy_utils/src/ty/mod.rs @@ -513,25 +513,31 @@ pub fn walk_ptrs_ty_depth(ty: Ty<'_>) -> (Ty<'_>, usize) { inner(ty, 0) } -/// Returns `true` if types `a` and `b` are same types having same `Const` generic args, -/// otherwise returns `false` -pub fn same_type_and_consts<'tcx>(a: Ty<'tcx>, b: Ty<'tcx>) -> bool { +/// Checks whether `a` and `b` are same types having same `Const` generic args, but ignores +/// lifetimes. +/// +/// For example, the function would return `true` for +/// - `u32` and `u32` +/// - `[u8; N]` and `[u8; M]`, if `N=M` +/// - `Option` and `Option`, if `same_type_modulo_regions(T, U)` holds +/// - `&'a str` and `&'b str` +/// +/// and `false` for: +/// - `Result` and `Result` +pub fn same_type_modulo_regions<'tcx>(a: Ty<'tcx>, b: Ty<'tcx>) -> bool { match (&a.kind(), &b.kind()) { (&ty::Adt(did_a, args_a), &ty::Adt(did_b, args_b)) => { if did_a != did_b { return false; } - args_a - .iter() - .zip(args_b.iter()) - .all(|(arg_a, arg_b)| match (arg_a.kind(), arg_b.kind()) { - (GenericArgKind::Const(inner_a), GenericArgKind::Const(inner_b)) => inner_a == inner_b, - (GenericArgKind::Type(type_a), GenericArgKind::Type(type_b)) => { - same_type_and_consts(type_a, type_b) - }, - _ => true, - }) + iter::zip(*args_a, *args_b).all(|(arg_a, arg_b)| match (arg_a.kind(), arg_b.kind()) { + (GenericArgKind::Const(inner_a), GenericArgKind::Const(inner_b)) => inner_a == inner_b, + (GenericArgKind::Type(type_a), GenericArgKind::Type(type_b)) => { + same_type_modulo_regions(type_a, type_b) + }, + _ => true, + }) }, _ => a == b, } diff --git a/tests/ui/use_self.fixed b/tests/ui/use_self.fixed index cccb6bffabb7..075e31d202b0 100644 --- a/tests/ui/use_self.fixed +++ b/tests/ui/use_self.fixed @@ -530,8 +530,8 @@ mod issue7206 { impl<'a> S2> { fn new_again() -> Self { - Self::new() - //~^ use_self + S2::new() + // FIXME: ^Broken by PR #15611 } } } @@ -755,3 +755,17 @@ mod crash_check_13128 { } } } + +mod issue_13277 { + trait Foo { + type Item<'foo>; + } + struct Bar<'b> { + content: &'b str, + } + impl<'b> Foo for Option> { + // when checking whether `Option>` has a lifetime, check not only the outer + // `Option`, but also the inner `Bar<'foo>` + type Item<'foo> = Option>; + } +} diff --git a/tests/ui/use_self.rs b/tests/ui/use_self.rs index 09288677aa71..6fbba0bbc550 100644 --- a/tests/ui/use_self.rs +++ b/tests/ui/use_self.rs @@ -531,7 +531,7 @@ mod issue7206 { impl<'a> S2> { fn new_again() -> Self { S2::new() - //~^ use_self + // FIXME: ^Broken by PR #15611 } } } @@ -755,3 +755,17 @@ mod crash_check_13128 { } } } + +mod issue_13277 { + trait Foo { + type Item<'foo>; + } + struct Bar<'b> { + content: &'b str, + } + impl<'b> Foo for Option> { + // when checking whether `Option>` has a lifetime, check not only the outer + // `Option`, but also the inner `Bar<'foo>` + type Item<'foo> = Option>; + } +} diff --git a/tests/ui/use_self.stderr b/tests/ui/use_self.stderr index 781327696ac1..5f65c53ea25c 100644 --- a/tests/ui/use_self.stderr +++ b/tests/ui/use_self.stderr @@ -169,12 +169,6 @@ error: unnecessary structure name repetition LL | A::new::(submod::B {}) | ^ help: use the applicable keyword: `Self` -error: unnecessary structure name repetition - --> tests/ui/use_self.rs:533:13 - | -LL | S2::new() - | ^^ help: use the applicable keyword: `Self` - error: unnecessary structure name repetition --> tests/ui/use_self.rs:571:17 | @@ -259,5 +253,5 @@ error: unnecessary structure name repetition LL | E::A => {}, | ^ help: use the applicable keyword: `Self` -error: aborting due to 43 previous errors +error: aborting due to 42 previous errors