X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=clippy_lints%2Fsrc%2Fuse_self.rs;h=4b9945d20b5c0a9405eb328edae5c95fa2891878;hb=e5a5b0a0774625eebbe7b29c67b49dc6431544d1;hp=1f1d9ddbfec40b61c573ee1d9303c198c9632bd7;hpb=13421e3945a28dad49226c4d08986eaacd1033d9;p=rust.git diff --git a/clippy_lints/src/use_self.rs b/clippy_lints/src/use_self.rs index 1f1d9ddbfec..4b9945d20b5 100644 --- a/clippy_lints/src/use_self.rs +++ b/clippy_lints/src/use_self.rs @@ -1,68 +1,68 @@ -use crate::utils::span_lint_and_sugg; use if_chain::if_chain; -use rustc::hir::def::{CtorKind, Def}; +use rustc::declare_lint_pass; +use rustc::hir; +use rustc::hir::def::{DefKind, Res}; use rustc::hir::intravisit::{walk_item, walk_path, walk_ty, NestedVisitorMap, Visitor}; use rustc::hir::*; use rustc::lint::{in_external_macro, LateContext, LateLintPass, LintArray, LintContext, LintPass}; use rustc::ty; -use rustc::{declare_tool_lint, lint_array}; +use rustc::ty::{DefIdTree, Ty}; use rustc_errors::Applicability; -use syntax_pos::symbol::keywords::SelfUpper; - -/// **What it does:** Checks for unnecessary repetition of structure name when a -/// replacement with `Self` is applicable. -/// -/// **Why is this bad?** Unnecessary repetition. Mixed use of `Self` and struct -/// name -/// feels inconsistent. -/// -/// **Known problems:** -/// - False positive when using associated types (#2843) -/// - False positives in some situations when using generics (#3410) -/// -/// **Example:** -/// ```rust -/// struct Foo {} -/// impl Foo { -/// fn new() -> Foo { -/// Foo {} -/// } -/// } -/// ``` -/// could be -/// ```rust -/// struct Foo {} -/// impl Foo { -/// fn new() -> Self { -/// Self {} -/// } -/// } -/// ``` +use rustc_session::declare_tool_lint; +use syntax_pos::symbol::kw; + +use crate::utils::{differing_macro_contexts, span_lint_and_sugg}; + declare_clippy_lint! { + /// **What it does:** Checks for unnecessary repetition of structure name when a + /// replacement with `Self` is applicable. + /// + /// **Why is this bad?** Unnecessary repetition. Mixed use of `Self` and struct + /// name + /// feels inconsistent. + /// + /// **Known problems:** + /// - False positive when using associated types (#2843) + /// - False positives in some situations when using generics (#3410) + /// + /// **Example:** + /// ```rust + /// struct Foo {} + /// impl Foo { + /// fn new() -> Foo { + /// Foo {} + /// } + /// } + /// ``` + /// could be + /// ```rust + /// struct Foo {} + /// impl Foo { + /// fn new() -> Self { + /// Self {} + /// } + /// } + /// ``` pub USE_SELF, - pedantic, + nursery, "Unnecessary structure name repetition whereas `Self` is applicable" } -#[derive(Copy, Clone, Default)] -pub struct UseSelf; +declare_lint_pass!(UseSelf => [USE_SELF]); -impl LintPass for UseSelf { - fn get_lints(&self) -> LintArray { - lint_array!(USE_SELF) - } +const SEGMENTS_MSG: &str = "segments should be composed of at least 1 element"; - fn name(&self) -> &'static str { - "UseSelf" - } -} +fn span_use_self_lint(cx: &LateContext<'_, '_>, path: &Path, last_segment: Option<&PathSegment>) { + let last_segment = last_segment.unwrap_or_else(|| path.segments.last().expect(SEGMENTS_MSG)); -const SEGMENTS_MSG: &str = "segments should be composed of at least 1 element"; + // Path segments only include actual path, no methods or fields. + let last_path_span = last_segment.ident.span; + + if differing_macro_contexts(path.span, last_path_span) { + return; + } -fn span_use_self_lint(cx: &LateContext<'_, '_>, path: &Path) { - // path segments only include actual path, no methods or fields - let last_path_span = path.segments.last().expect(SEGMENTS_MSG).ident.span; - // only take path up to the end of last_path_span + // Only take path up to the end of last_path_span. let span = path.span.with_hi(last_path_span.hi()); span_lint_and_sugg( @@ -76,34 +76,30 @@ fn span_use_self_lint(cx: &LateContext<'_, '_>, path: &Path) { ); } -struct TraitImplTyVisitor<'a, 'tcx: 'a> { - item_type: ty::Ty<'tcx>, +struct TraitImplTyVisitor<'a, 'tcx> { + item_type: Ty<'tcx>, cx: &'a LateContext<'a, 'tcx>, trait_type_walker: ty::walk::TypeWalker<'tcx>, impl_type_walker: ty::walk::TypeWalker<'tcx>, } impl<'a, 'tcx> Visitor<'tcx> for TraitImplTyVisitor<'a, 'tcx> { - fn visit_ty(&mut self, t: &'tcx Ty) { + fn visit_ty(&mut self, t: &'tcx hir::Ty) { let trait_ty = self.trait_type_walker.next(); let impl_ty = self.impl_type_walker.next(); - if let TyKind::Path(QPath::Resolved(_, path)) = &t.node { + if_chain! { + if let TyKind::Path(QPath::Resolved(_, path)) = &t.kind; + // The implementation and trait types don't match which means that // the concrete type was specified by the implementation - if impl_ty != trait_ty { - if let Some(impl_ty) = impl_ty { - if self.item_type == impl_ty { - let is_self_ty = if let def::Def::SelfTy(..) = path.def { - true - } else { - false - }; - - if !is_self_ty { - span_use_self_lint(self.cx, path); - } - } + if impl_ty != trait_ty; + if let Some(impl_ty) = impl_ty; + if self.item_type == impl_ty; + then { + match path.res { + def::Res::SelfTy(..) => {}, + _ => span_use_self_lint(self.cx, path, None) } } } @@ -116,9 +112,9 @@ fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> { } } -fn check_trait_method_impl_decl<'a, 'tcx: 'a>( +fn check_trait_method_impl_decl<'a, 'tcx>( cx: &'a LateContext<'a, 'tcx>, - item_type: ty::Ty<'tcx>, + item_type: Ty<'tcx>, impl_item: &ImplItem, impl_decl: &'tcx FnDecl, impl_trait_ref: &ty::TraitRef<'_>, @@ -127,7 +123,7 @@ fn check_trait_method_impl_decl<'a, 'tcx: 'a>( .tcx .associated_items(impl_trait_ref.def_id) .find(|assoc_item| { - assoc_item.kind == ty::AssociatedKind::Method + assoc_item.kind == ty::AssocKind::Method && cx .tcx .hygienic_eq(impl_item.ident, assoc_item.ident, impl_trait_ref.def_id) @@ -137,7 +133,7 @@ fn check_trait_method_impl_decl<'a, 'tcx: 'a>( let trait_method_sig = cx.tcx.fn_sig(trait_method.def_id); let trait_method_sig = cx.tcx.erase_late_bound_regions(&trait_method_sig); - let impl_method_def_id = cx.tcx.hir().local_def_id(impl_item.id); + let impl_method_def_id = cx.tcx.hir().local_def_id(impl_item.hir_id); let impl_method_sig = cx.tcx.fn_sig(impl_method_def_id); let impl_method_sig = cx.tcx.erase_late_bound_regions(&impl_method_sig); @@ -149,7 +145,7 @@ fn check_trait_method_impl_decl<'a, 'tcx: 'a>( // `impl_decl_ty` (of type `hir::Ty`) represents the type declared in the signature. // `impl_ty` (of type `ty:TyS`) is the concrete type that the compiler has determined for - // that declaration. We use `impl_decl_ty` to see if the type was declared as `Self` + // that declaration. We use `impl_decl_ty` to see if the type was declared as `Self` // and use `impl_ty` to check its concrete type. for (impl_decl_ty, (impl_ty, trait_ty)) in impl_decl.inputs.iter().chain(output_ty).zip( impl_method_sig @@ -174,14 +170,14 @@ fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) { return; } if_chain! { - if let ItemKind::Impl(.., ref item_type, ref refs) = item.node; - if let TyKind::Path(QPath::Resolved(_, ref item_path)) = item_type.node; + if let ItemKind::Impl(.., ref item_type, ref refs) = item.kind; + if let TyKind::Path(QPath::Resolved(_, ref item_path)) = item_type.kind; then { let parameters = &item_path.segments.last().expect(SEGMENTS_MSG).args; let should_check = if let Some(ref params) = *parameters { !params.parenthesized && !params.args.iter().any(|arg| match arg { GenericArg::Lifetime(_) => true, - GenericArg::Type(_) => false, + _ => false, }) } else { true @@ -192,14 +188,14 @@ fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) { item_path, cx, }; - let impl_def_id = cx.tcx.hir().local_def_id(item.id); + let impl_def_id = cx.tcx.hir().local_def_id(item.hir_id); let impl_trait_ref = cx.tcx.impl_trait_ref(impl_def_id); if let Some(impl_trait_ref) = impl_trait_ref { for impl_item_ref in refs { let impl_item = cx.tcx.hir().impl_item(impl_item_ref.id); - if let ImplItemKind::Method(MethodSig{ decl: impl_decl, .. }, impl_body_id) - = &impl_item.node { + if let ImplItemKind::Method(FnSig{ decl: impl_decl, .. }, impl_body_id) + = &impl_item.kind { let item_type = cx.tcx.type_of(impl_def_id); check_trait_method_impl_decl(cx, item_type, impl_item, impl_decl, &impl_trait_ref); @@ -221,33 +217,55 @@ fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) { } } -struct UseSelfVisitor<'a, 'tcx: 'a> { +struct UseSelfVisitor<'a, 'tcx> { item_path: &'a Path, cx: &'a LateContext<'a, 'tcx>, } impl<'a, 'tcx> Visitor<'tcx> for UseSelfVisitor<'a, 'tcx> { fn visit_path(&mut self, path: &'tcx Path, _id: HirId) { - if path.segments.last().expect(SEGMENTS_MSG).ident.name != SelfUpper.name() { - if self.item_path.def == path.def { - span_use_self_lint(self.cx, path); - } else if let Def::StructCtor(ctor_did, CtorKind::Fn) = path.def { - if self.item_path.def.opt_def_id() == self.cx.tcx.parent_def_id(ctor_did) { - span_use_self_lint(self.cx, path); + if !path.segments.iter().any(|p| p.ident.span.is_dummy()) { + if path.segments.len() >= 2 { + let last_but_one = &path.segments[path.segments.len() - 2]; + if last_but_one.ident.name != kw::SelfUpper { + let enum_def_id = match path.res { + Res::Def(DefKind::Variant, variant_def_id) => self.cx.tcx.parent(variant_def_id), + Res::Def(DefKind::Ctor(def::CtorOf::Variant, _), ctor_def_id) => { + let variant_def_id = self.cx.tcx.parent(ctor_def_id); + variant_def_id.and_then(|def_id| self.cx.tcx.parent(def_id)) + }, + _ => None, + }; + + if self.item_path.res.opt_def_id() == enum_def_id { + span_use_self_lint(self.cx, path, Some(last_but_one)); + } + } + } + + if path.segments.last().expect(SEGMENTS_MSG).ident.name != kw::SelfUpper { + if self.item_path.res == path.res { + span_use_self_lint(self.cx, path, None); + } else if let Res::Def(DefKind::Ctor(def::CtorOf::Struct, _), ctor_def_id) = path.res { + if self.item_path.res.opt_def_id() == self.cx.tcx.parent(ctor_def_id) { + span_use_self_lint(self.cx, path, None); + } } } } + walk_path(self, path); } fn visit_item(&mut self, item: &'tcx Item) { - match item.node { + match item.kind { ItemKind::Use(..) | ItemKind::Static(..) | ItemKind::Enum(..) | ItemKind::Struct(..) | ItemKind::Union(..) - | ItemKind::Impl(..) => { + | ItemKind::Impl(..) + | ItemKind::Fn(..) => { // Don't check statements that shadow `Self` or where `Self` can't be used }, _ => walk_item(self, item),