+use crate::utils::{in_macro, meets_msrv, snippet_opt, span_lint_and_sugg};
use if_chain::if_chain;
-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::ty::{DefIdTree, Ty};
-use rustc_errors::Applicability;
-use rustc_session::declare_tool_lint;
-use syntax_pos::symbol::kw;
-use crate::utils::{differing_macro_contexts, span_lint_and_sugg};
+use rustc_errors::Applicability;
+use rustc_hir as hir;
+use rustc_hir::def::DefKind;
+use rustc_hir::{
+ def,
+ def_id::LocalDefId,
+ intravisit::{walk_ty, NestedVisitorMap, Visitor},
+ Expr, ExprKind, FnRetTy, FnSig, GenericArg, HirId, Impl, ImplItemKind, Item, ItemKind, Node, Path, PathSegment,
+ QPath, TyKind,
+};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_middle::hir::map::Map;
+use rustc_middle::ty::{AssocKind, Ty, TyS};
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::{BytePos, Span};
+use rustc_typeck::hir_ty_to_ty;
declare_clippy_lint! {
/// **What it does:** Checks for unnecessary repetition of structure name when a
/// feels inconsistent.
///
/// **Known problems:**
- /// - False positive when using associated types (#2843)
- /// - False positives in some situations when using generics (#3410)
+ /// - Unaddressed false negative in fn bodies of trait implementations
+ /// - False positive with assotiated types in traits (#4140)
///
/// **Example:**
+ ///
/// ```rust
/// struct Foo {}
/// impl Foo {
/// ```
pub USE_SELF,
nursery,
- "Unnecessary structure name repetition whereas `Self` is applicable"
+ "unnecessary structure name repetition whereas `Self` is applicable"
}
-declare_lint_pass!(UseSelf => [USE_SELF]);
-
-const SEGMENTS_MSG: &str = "segments should be composed of at least 1 element";
-
-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));
+#[derive(Default)]
+pub struct UseSelf {
+ msrv: Option<RustcVersion>,
+ stack: Vec<StackItem>,
+}
- // Path segments only include actual path, no methods or fields.
- let last_path_span = last_segment.ident.span;
+const USE_SELF_MSRV: RustcVersion = RustcVersion::new(1, 37, 0);
- if differing_macro_contexts(path.span, last_path_span) {
- return;
+impl UseSelf {
+ #[must_use]
+ pub fn new(msrv: Option<RustcVersion>) -> Self {
+ Self {
+ msrv,
+ ..Self::default()
+ }
}
-
- // 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(
- cx,
- USE_SELF,
- span,
- "unnecessary structure name repetition",
- "use the applicable keyword",
- "Self".to_owned(),
- Applicability::MachineApplicable,
- );
}
-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>,
+#[derive(Debug)]
+enum StackItem {
+ Check {
+ hir_id: HirId,
+ impl_trait_ref_def_id: Option<LocalDefId>,
+ types_to_skip: Vec<HirId>,
+ types_to_lint: Vec<HirId>,
+ },
+ NoCheck,
}
-impl<'a, 'tcx> Visitor<'tcx> for TraitImplTyVisitor<'a, 'tcx> {
- 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();
+impl_lint_pass!(UseSelf => [USE_SELF]);
- if_chain! {
- if let TyKind::Path(QPath::Resolved(_, path)) = &t.kind;
+const SEGMENTS_MSG: &str = "segments should be composed of at least 1 element";
- // 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;
- then {
- match path.res {
- def::Res::SelfTy(..) => {},
- _ => span_use_self_lint(self.cx, path, None)
+impl<'tcx> LateLintPass<'tcx> for UseSelf {
+ fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
+ // We push the self types of `impl`s on a stack here. Only the top type on the stack is
+ // relevant for linting, since this is the self type of the `impl` we're currently in. To
+ // avoid linting on nested items, we push `StackItem::NoCheck` on the stack to signal, that
+ // we're in an `impl` or nested item, that we don't want to lint
+ //
+ // NB: If you push something on the stack in this method, remember to also pop it in the
+ // `check_item_post` method.
+ match &item.kind {
+ ItemKind::Impl(Impl {
+ self_ty: hir_self_ty,
+ of_trait,
+ ..
+ }) => {
+ let should_check = if let TyKind::Path(QPath::Resolved(_, ref item_path)) = hir_self_ty.kind {
+ let parameters = &item_path.segments.last().expect(SEGMENTS_MSG).args;
+ parameters.as_ref().map_or(true, |params| {
+ !params.parenthesized && !params.args.iter().any(|arg| matches!(arg, GenericArg::Lifetime(_)))
+ })
+ } else {
+ false
+ };
+ let impl_trait_ref_def_id = of_trait.as_ref().map(|_| cx.tcx.hir().local_def_id(item.hir_id()));
+ if should_check {
+ self.stack.push(StackItem::Check {
+ hir_id: hir_self_ty.hir_id,
+ impl_trait_ref_def_id,
+ types_to_lint: Vec::new(),
+ types_to_skip: Vec::new(),
+ });
+ } else {
+ self.stack.push(StackItem::NoCheck);
}
- }
+ },
+ ItemKind::Static(..)
+ | ItemKind::Const(..)
+ | ItemKind::Fn(..)
+ | ItemKind::Enum(..)
+ | ItemKind::Struct(..)
+ | ItemKind::Union(..)
+ | ItemKind::Trait(..) => {
+ self.stack.push(StackItem::NoCheck);
+ },
+ _ => (),
}
-
- walk_ty(self, t)
}
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
- NestedVisitorMap::None
+ fn check_item_post(&mut self, _: &LateContext<'_>, item: &Item<'_>) {
+ use ItemKind::{Const, Enum, Fn, Impl, Static, Struct, Trait, Union};
+ match item.kind {
+ Impl { .. } | Static(..) | Const(..) | Fn(..) | Enum(..) | Struct(..) | Union(..) | Trait(..) => {
+ self.stack.pop();
+ },
+ _ => (),
+ }
}
-}
-fn check_trait_method_impl_decl<'a, 'tcx>(
- cx: &'a LateContext<'a, 'tcx>,
- item_type: Ty<'tcx>,
- impl_item: &ImplItem<'_>,
- impl_decl: &'tcx FnDecl,
- impl_trait_ref: &ty::TraitRef<'_>,
-) {
- let trait_method = cx
- .tcx
- .associated_items(impl_trait_ref.def_id)
- .find(|assoc_item| {
- assoc_item.kind == ty::AssocKind::Method
- && cx
- .tcx
- .hygienic_eq(impl_item.ident, assoc_item.ident, impl_trait_ref.def_id)
- })
- .expect("impl method matches a trait method");
+ fn check_impl_item(&mut self, cx: &LateContext<'_>, impl_item: &hir::ImplItem<'_>) {
+ // We want to skip types in trait `impl`s that aren't declared as `Self` in the trait
+ // declaration. The collection of those types is all this method implementation does.
+ if_chain! {
+ if let ImplItemKind::Fn(FnSig { decl, .. }, ..) = impl_item.kind;
+ if let Some(&mut StackItem::Check {
+ impl_trait_ref_def_id: Some(def_id),
+ ref mut types_to_skip,
+ ..
+ }) = self.stack.last_mut();
+ if let Some(impl_trait_ref) = cx.tcx.impl_trait_ref(def_id);
+ then {
+ // `self_ty` is the semantic self type of `impl <trait> for <type>`. This cannot be
+ // `Self`.
+ let self_ty = impl_trait_ref.self_ty();
- 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);
+ // `trait_method_sig` is the signature of the function, how it is declared in the
+ // trait, not in the impl of the trait.
+ let trait_method = cx
+ .tcx
+ .associated_items(impl_trait_ref.def_id)
+ .find_by_name_and_kind(cx.tcx, impl_item.ident, AssocKind::Fn, impl_trait_ref.def_id)
+ .expect("impl method matches a trait method");
+ 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);
+
+ // `impl_inputs_outputs` is an iterator over the types (`hir::Ty`) declared in the
+ // implementation of the trait.
+ let output_hir_ty = if let FnRetTy::Return(ty) = &decl.output {
+ Some(&**ty)
+ } else {
+ None
+ };
+ let impl_inputs_outputs = decl.inputs.iter().chain(output_hir_ty);
+
+ // `impl_hir_ty` (of type `hir::Ty`) represents the type written in the signature.
+ //
+ // `trait_sem_ty` (of type `ty::Ty`) is the semantic type for the signature in the
+ // trait declaration. This is used to check if `Self` was used in the trait
+ // declaration.
+ //
+ // If `any`where in the `trait_sem_ty` the `self_ty` was used verbatim (as opposed
+ // to `Self`), we want to skip linting that type and all subtypes of it. This
+ // avoids suggestions to e.g. replace `Vec<u8>` with `Vec<Self>`, in an `impl Trait
+ // for u8`, when the trait always uses `Vec<u8>`.
+ //
+ // See also https://github.com/rust-lang/rust-clippy/issues/2894.
+ for (impl_hir_ty, trait_sem_ty) in impl_inputs_outputs.zip(trait_method_sig.inputs_and_output) {
+ if trait_sem_ty.walk().any(|inner| inner == self_ty.into()) {
+ let mut visitor = SkipTyCollector::default();
+ visitor.visit_ty(&impl_hir_ty);
+ types_to_skip.extend(visitor.types_to_skip);
+ }
+ }
+ }
+ }
+ }
- 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);
+ fn check_body(&mut self, cx: &LateContext<'tcx>, body: &'tcx hir::Body<'_>) {
+ // `hir_ty_to_ty` cannot be called in `Body`s or it will panic (sometimes). But in bodies
+ // we can use `cx.typeck_results.node_type(..)` to get the `ty::Ty` from a `hir::Ty`.
+ // However the `node_type()` method can *only* be called in bodies.
+ //
+ // This method implementation determines which types should get linted in a `Body` and
+ // which shouldn't, with a visitor. We could directly lint in the visitor, but then we
+ // could only allow this lint on item scope. And we would have to check if those types are
+ // already dealt with in `check_ty` anyway.
+ if let Some(StackItem::Check {
+ hir_id,
+ types_to_lint,
+ types_to_skip,
+ ..
+ }) = self.stack.last_mut()
+ {
+ let self_ty = ty_from_hir_id(cx, *hir_id);
+
+ let mut visitor = LintTyCollector {
+ cx,
+ self_ty,
+ types_to_lint: vec![],
+ types_to_skip: vec![],
+ };
+ visitor.visit_expr(&body.value);
+ types_to_lint.extend(visitor.types_to_lint);
+ types_to_skip.extend(visitor.types_to_skip);
+ }
+ }
- let output_ty = if let FunctionRetTy::Return(ty) = &impl_decl.output {
- Some(&**ty)
- } else {
- None
- };
+ fn check_ty(&mut self, cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>) {
+ if in_macro(hir_ty.span) | in_impl(cx, hir_ty) | !meets_msrv(self.msrv.as_ref(), &USE_SELF_MSRV) {
+ return;
+ }
- // `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`
- // 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
- .inputs_and_output
- .iter()
- .zip(trait_method_sig.inputs_and_output),
- ) {
- let mut visitor = TraitImplTyVisitor {
- cx,
- item_type,
- trait_type_walker: trait_ty.walk(),
- impl_type_walker: impl_ty.walk(),
+ let lint_dependend_on_expr_kind = if let Some(StackItem::Check {
+ hir_id,
+ types_to_lint,
+ types_to_skip,
+ ..
+ }) = self.stack.last()
+ {
+ if types_to_skip.contains(&hir_ty.hir_id) {
+ false
+ } else if types_to_lint.contains(&hir_ty.hir_id) {
+ true
+ } else {
+ let self_ty = ty_from_hir_id(cx, *hir_id);
+ should_lint_ty(hir_ty, hir_ty_to_ty(cx.tcx, hir_ty), self_ty)
+ }
+ } else {
+ false
};
- visitor.visit_ty(&impl_decl_ty);
+ if lint_dependend_on_expr_kind {
+ // FIXME: this span manipulation should not be necessary
+ // @flip1995 found an ast lowering issue in
+ // https://github.com/rust-lang/rust/blob/master/src/librustc_ast_lowering/path.rs#l142-l162
+ let hir = cx.tcx.hir();
+ let id = hir.get_parent_node(hir_ty.hir_id);
+
+ if !hir.opt_span(id).map_or(false, in_macro) {
+ match hir.find(id) {
+ Some(Node::Expr(Expr {
+ kind: ExprKind::Path(QPath::TypeRelative(_, segment)),
+ ..
+ })) => span_lint_until_last_segment(cx, hir_ty.span, segment),
+ _ => span_lint(cx, hir_ty.span),
+ }
+ }
+ }
}
-}
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UseSelf {
- fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item<'_>) {
- if in_external_macro(cx.sess(), item.span) {
+ fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
+ fn expr_ty_matches(cx: &LateContext<'_>, expr: &Expr<'_>, self_ty: Ty<'_>) -> bool {
+ let def_id = expr.hir_id.owner;
+ if cx.tcx.has_typeck_results(def_id) {
+ cx.tcx.typeck(def_id).expr_ty_opt(expr) == Some(self_ty)
+ } else {
+ false
+ }
+ }
+
+ if in_macro(expr.span) | !meets_msrv(self.msrv.as_ref(), &USE_SELF_MSRV) {
return;
}
- if_chain! {
- if let ItemKind::Impl(.., ref item_type, 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,
- _ => false,
- })
- } else {
- true
- };
- if should_check {
- let visitor = &mut UseSelfVisitor {
- item_path,
- cx,
- };
- 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(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);
-
- let body = cx.tcx.hir().body(*impl_body_id);
- visitor.visit_body(body);
- } else {
- visitor.visit_impl_item(impl_item);
- }
+ if let Some(StackItem::Check { hir_id, .. }) = self.stack.last() {
+ let self_ty = ty_from_hir_id(cx, *hir_id);
+
+ match &expr.kind {
+ ExprKind::Struct(QPath::Resolved(_, path), ..) => {
+ if expr_ty_matches(cx, expr, self_ty) {
+ match path.res {
+ def::Res::SelfTy(..) => (),
+ def::Res::Def(DefKind::Variant, _) => span_lint_on_path_until_last_segment(cx, path),
+ _ => {
+ span_lint(cx, path.span);
+ },
}
- } else {
- for impl_item_ref in refs {
- let impl_item = cx.tcx.hir().impl_item(impl_item_ref.id);
- visitor.visit_impl_item(impl_item);
+ }
+ },
+ // tuple struct instantiation (`Foo(arg)` or `Enum::Foo(arg)`)
+ ExprKind::Call(fun, _) => {
+ if let Expr {
+ kind: ExprKind::Path(ref qpath),
+ ..
+ } = fun
+ {
+ if expr_ty_matches(cx, expr, self_ty) {
+ let res = cx.qpath_res(qpath, fun.hir_id);
+
+ if let def::Res::Def(DefKind::Ctor(ctor_of, _), ..) = res {
+ match ctor_of {
+ def::CtorOf::Variant => {
+ span_lint_on_qpath_resolved(cx, qpath, true);
+ },
+ def::CtorOf::Struct => {
+ span_lint_on_qpath_resolved(cx, qpath, false);
+ },
+ }
+ }
}
}
- }
+ },
+ // unit enum variants (`Enum::A`)
+ ExprKind::Path(qpath) => {
+ if expr_ty_matches(cx, expr, self_ty) {
+ span_lint_on_qpath_resolved(cx, &qpath, true);
+ }
+ },
+ _ => (),
}
}
}
+
+ extract_msrv_attr!(LateContext);
}
-struct UseSelfVisitor<'a, 'tcx> {
- item_path: &'a Path,
- cx: &'a LateContext<'a, 'tcx>,
+#[derive(Default)]
+struct SkipTyCollector {
+ types_to_skip: Vec<HirId>,
}
-impl<'a, 'tcx> Visitor<'tcx> for UseSelfVisitor<'a, 'tcx> {
- fn visit_path(&mut self, path: &'tcx Path, _id: HirId) {
- 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));
- }
- }
- }
+impl<'tcx> Visitor<'tcx> for SkipTyCollector {
+ type Map = Map<'tcx>;
- 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);
- }
- }
+ fn visit_ty(&mut self, hir_ty: &hir::Ty<'_>) {
+ self.types_to_skip.push(hir_ty.hir_id);
+
+ walk_ty(self, hir_ty)
+ }
+
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+ NestedVisitorMap::None
+ }
+}
+
+struct LintTyCollector<'a, 'tcx> {
+ cx: &'a LateContext<'tcx>,
+ self_ty: Ty<'tcx>,
+ types_to_lint: Vec<HirId>,
+ types_to_skip: Vec<HirId>,
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for LintTyCollector<'a, 'tcx> {
+ type Map = Map<'tcx>;
+
+ fn visit_ty(&mut self, hir_ty: &'tcx hir::Ty<'_>) {
+ if_chain! {
+ if let Some(ty) = self.cx.typeck_results().node_type_opt(hir_ty.hir_id);
+ if should_lint_ty(hir_ty, ty, self.self_ty);
+ then {
+ self.types_to_lint.push(hir_ty.hir_id);
+ } else {
+ self.types_to_skip.push(hir_ty.hir_id);
}
}
- walk_path(self, path);
+ walk_ty(self, hir_ty)
}
- fn visit_item(&mut self, item: &'tcx Item<'_>) {
- match item.kind {
- ItemKind::Use(..)
- | ItemKind::Static(..)
- | ItemKind::Enum(..)
- | ItemKind::Struct(..)
- | ItemKind::Union(..)
- | ItemKind::Impl(..)
- | ItemKind::Fn(..) => {
- // Don't check statements that shadow `Self` or where `Self` can't be used
- },
- _ => walk_item(self, item),
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+ NestedVisitorMap::None
+ }
+}
+
+fn span_lint(cx: &LateContext<'_>, span: Span) {
+ span_lint_and_sugg(
+ cx,
+ USE_SELF,
+ span,
+ "unnecessary structure name repetition",
+ "use the applicable keyword",
+ "Self".to_owned(),
+ Applicability::MachineApplicable,
+ );
+}
+
+#[allow(clippy::cast_possible_truncation)]
+fn span_lint_until_last_segment(cx: &LateContext<'_>, span: Span, segment: &PathSegment<'_>) {
+ let sp = span.with_hi(segment.ident.span.lo());
+ // remove the trailing ::
+ let span_without_last_segment = match snippet_opt(cx, sp) {
+ Some(snippet) => match snippet.rfind("::") {
+ Some(bidx) => sp.with_hi(sp.lo() + BytePos(bidx as u32)),
+ None => sp,
+ },
+ None => sp,
+ };
+ span_lint(cx, span_without_last_segment);
+}
+
+fn span_lint_on_path_until_last_segment(cx: &LateContext<'_>, path: &Path<'_>) {
+ if path.segments.len() > 1 {
+ span_lint_until_last_segment(cx, path.span, path.segments.last().unwrap());
+ }
+}
+
+fn span_lint_on_qpath_resolved(cx: &LateContext<'_>, qpath: &QPath<'_>, until_last_segment: bool) {
+ if let QPath::Resolved(_, path) = qpath {
+ if until_last_segment {
+ span_lint_on_path_until_last_segment(cx, path);
+ } else {
+ span_lint(cx, path.span);
+ }
+ }
+}
+
+fn ty_from_hir_id<'tcx>(cx: &LateContext<'tcx>, hir_id: HirId) -> Ty<'tcx> {
+ if let Some(Node::Ty(hir_ty)) = cx.tcx.hir().find(hir_id) {
+ hir_ty_to_ty(cx.tcx, hir_ty)
+ } else {
+ unreachable!("This function should only be called with `HirId`s that are for sure `Node::Ty`")
+ }
+}
+
+fn in_impl(cx: &LateContext<'tcx>, hir_ty: &hir::Ty<'_>) -> bool {
+ let map = cx.tcx.hir();
+ let parent = map.get_parent_node(hir_ty.hir_id);
+ if_chain! {
+ if let Some(Node::Item(item)) = map.find(parent);
+ if let ItemKind::Impl { .. } = item.kind;
+ then {
+ true
+ } else {
+ false
}
}
+}
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
- NestedVisitorMap::All(&self.cx.tcx.hir())
+fn should_lint_ty(hir_ty: &hir::Ty<'_>, ty: Ty<'_>, self_ty: Ty<'_>) -> bool {
+ if_chain! {
+ if TyS::same_type(ty, self_ty);
+ if let TyKind::Path(QPath::Resolved(_, path)) = hir_ty.kind;
+ then {
+ !matches!(path.res, def::Res::SelfTy(..))
+ } else {
+ false
+ }
}
}