diff options
Diffstat (limited to 'compiler/rustc_lint/src/non_local_def.rs')
| -rw-r--r-- | compiler/rustc_lint/src/non_local_def.rs | 214 |
1 files changed, 179 insertions, 35 deletions
diff --git a/compiler/rustc_lint/src/non_local_def.rs b/compiler/rustc_lint/src/non_local_def.rs index 87ee5f53628..42b03f47a5b 100644 --- a/compiler/rustc_lint/src/non_local_def.rs +++ b/compiler/rustc_lint/src/non_local_def.rs @@ -1,3 +1,6 @@ +use rustc_errors::MultiSpan; +use rustc_hir::intravisit::{self, Visitor}; +use rustc_hir::HirId; use rustc_hir::{def::DefKind, Body, Item, ItemKind, Node, TyKind}; use rustc_hir::{Path, QPath}; use rustc_infer::infer::InferCtxt; @@ -7,12 +10,13 @@ use rustc_middle::ty::{EarlyBinder, TraitRef, TypeSuperFoldable}; use rustc_session::{declare_lint, impl_lint_pass}; use rustc_span::def_id::{DefId, LOCAL_CRATE}; use rustc_span::Span; -use rustc_span::{sym, symbol::kw, ExpnKind, MacroKind}; +use rustc_span::{sym, symbol::kw, ExpnKind, MacroKind, Symbol}; use rustc_trait_selection::infer::TyCtxtInferExt; use rustc_trait_selection::traits::error_reporting::ambiguity::{ compute_applicable_impls_for_diagnostics, CandidateSource, }; +use crate::fluent_generated as fluent; use crate::lints::{NonLocalDefinitionsCargoUpdateNote, NonLocalDefinitionsDiag}; use crate::{LateContext, LateLintPass, LintContext}; @@ -134,35 +138,8 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions { }; // Part 1: Is the Self type local? - let self_ty_has_local_parent = match impl_.self_ty.kind { - TyKind::Path(QPath::Resolved(_, ty_path)) => { - path_has_local_parent(ty_path, cx, parent, parent_parent) - } - TyKind::TraitObject([principle_poly_trait_ref, ..], _, _) => { - path_has_local_parent( - principle_poly_trait_ref.trait_ref.path, - cx, - parent, - parent_parent, - ) - } - TyKind::TraitObject([], _, _) - | TyKind::InferDelegation(_, _) - | TyKind::Slice(_) - | TyKind::Array(_, _) - | TyKind::Ptr(_) - | TyKind::Ref(_, _) - | TyKind::BareFn(_) - | TyKind::Never - | TyKind::Tup(_) - | TyKind::Path(_) - | TyKind::Pat(..) - | TyKind::AnonAdt(_) - | TyKind::OpaqueDef(_, _, _) - | TyKind::Typeof(_) - | TyKind::Infer - | TyKind::Err(_) => false, - }; + let self_ty_has_local_parent = + ty_has_local_parent(&impl_.self_ty.kind, cx, parent, parent_parent); if self_ty_has_local_parent { return; @@ -202,8 +179,7 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions { // Get the span of the parent const item ident (if it's a not a const anon). // // Used to suggest changing the const item to a const anon. - let span_for_const_anon_suggestion = if self.body_depth == 1 - && parent_def_kind == DefKind::Const + let span_for_const_anon_suggestion = if parent_def_kind == DefKind::Const && parent_opt_item_name != Some(kw::Underscore) && let Some(parent) = parent.as_local() && let Node::Item(item) = cx.tcx.hir_node_by_def_id(parent) @@ -215,9 +191,76 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions { None }; + let mut collector = PathCollector { paths: Vec::new() }; + collector.visit_ty(&impl_.self_ty); + if let Some(of_trait) = &impl_.of_trait { + collector.visit_trait_ref(of_trait); + } + collector.visit_generics(&impl_.generics); + + let mut may_move: Vec<Span> = collector + .paths + .into_iter() + .filter_map(|path| { + if let Some(did) = path.res.opt_def_id() + && did_has_local_parent(did, cx.tcx, parent, parent_parent) + { + Some(cx.tcx.def_span(did)) + } else { + None + } + }) + .collect(); + may_move.sort(); + may_move.dedup(); + + let const_anon = matches!(parent_def_kind, DefKind::Const | DefKind::Static { .. }) + .then_some(span_for_const_anon_suggestion); + + let may_remove = match &impl_.self_ty.kind { + TyKind::Ptr(mut_ty) | TyKind::Ref(_, mut_ty) + if ty_has_local_parent(&mut_ty.ty.kind, cx, parent, parent_parent) => + { + let type_ = + if matches!(impl_.self_ty.kind, TyKind::Ptr(_)) { "*" } else { "&" }; + let part = format!("{}{}", type_, mut_ty.mutbl.prefix_str()); + Some((impl_.self_ty.span.shrink_to_lo().until(mut_ty.ty.span), part)) + } + _ => None, + }; + + let impl_span = item.span.shrink_to_lo().to(impl_.self_ty.span); + let mut ms = MultiSpan::from_span(impl_span); + + let (self_ty_span, self_ty_str) = + self_ty_kind_for_diagnostic(&impl_.self_ty, cx.tcx); + + ms.push_span_label( + self_ty_span, + fluent::lint_non_local_definitions_self_ty_not_local, + ); + let of_trait_str = if let Some(of_trait) = &impl_.of_trait { + ms.push_span_label( + path_span_without_args(&of_trait.path), + fluent::lint_non_local_definitions_of_trait_not_local, + ); + Some(path_name_to_string(&of_trait.path)) + } else { + None + }; + let move_to = if may_move.is_empty() { + ms.push_span_label( + cx.tcx.def_span(parent), + fluent::lint_non_local_definitions_impl_move_help, + ); + None + } else { + Some((cx.tcx.def_span(parent), may_move)) + }; + cx.emit_span_lint( NON_LOCAL_DEFINITIONS, - item.span, + ms, NonLocalDefinitionsDiag::Impl { depth: self.body_depth, body_kind_descr: cx.tcx.def_kind_descr(parent_def_kind, parent), @@ -225,7 +268,12 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions { .map(|s| s.to_ident_string()) .unwrap_or_else(|| "<unnameable>".to_string()), cargo_update: cargo_update(), - const_anon: span_for_const_anon_suggestion, + const_anon, + self_ty_str, + of_trait_str, + move_to, + may_remove, + has_trait: impl_.of_trait.is_some(), }, ) } @@ -250,7 +298,6 @@ impl<'tcx> LateLintPass<'tcx> for NonLocalDefinitions { cargo_update: cargo_update(), help: (!is_at_toplevel_doctest).then_some(()), doctest_help: is_at_toplevel_doctest.then_some(()), - notes: (), }, ) } @@ -343,6 +390,54 @@ impl<'a, 'tcx, F: FnMut(DefId) -> bool> TypeFolder<TyCtxt<'tcx>> } } +/// Simple hir::Path collector +struct PathCollector<'tcx> { + paths: Vec<Path<'tcx>>, +} + +impl<'tcx> Visitor<'tcx> for PathCollector<'tcx> { + fn visit_path(&mut self, path: &Path<'tcx>, _id: HirId) { + self.paths.push(path.clone()); // need to clone, bc of the restricted lifetime + intravisit::walk_path(self, path) + } +} + +/// Given a `Ty` we check if the (outermost) type is local. +fn ty_has_local_parent( + ty_kind: &TyKind<'_>, + cx: &LateContext<'_>, + impl_parent: DefId, + impl_parent_parent: Option<DefId>, +) -> bool { + match ty_kind { + TyKind::Path(QPath::Resolved(_, ty_path)) => { + path_has_local_parent(ty_path, cx, impl_parent, impl_parent_parent) + } + TyKind::TraitObject([principle_poly_trait_ref, ..], _, _) => path_has_local_parent( + principle_poly_trait_ref.trait_ref.path, + cx, + impl_parent, + impl_parent_parent, + ), + TyKind::TraitObject([], _, _) + | TyKind::InferDelegation(_, _) + | TyKind::Slice(_) + | TyKind::Array(_, _) + | TyKind::Ptr(_) + | TyKind::Ref(_, _) + | TyKind::BareFn(_) + | TyKind::Never + | TyKind::Tup(_) + | TyKind::Path(_) + | TyKind::Pat(..) + | TyKind::AnonAdt(_) + | TyKind::OpaqueDef(_, _, _) + | TyKind::Typeof(_) + | TyKind::Infer + | TyKind::Err(_) => false, + } +} + /// Given a path and a parent impl def id, this checks if the if parent resolution /// def id correspond to the def id of the parent impl definition. /// @@ -384,3 +479,52 @@ fn did_has_local_parent( false } } + +/// Return for a given `Path` the span until the last args +fn path_span_without_args(path: &Path<'_>) -> Span { + if let Some(args) = &path.segments.last().unwrap().args { + path.span.until(args.span_ext) + } else { + path.span + } +} + +/// Return a "error message-able" ident for the last segment of the `Path` +fn path_name_to_string(path: &Path<'_>) -> String { + path.segments.last().unwrap().ident.name.to_ident_string() +} + +/// Compute the `Span` and visual representation for the `Self` we want to point at; +/// It follows part of the actual logic of non-local, and if possible return the least +/// amount possible for the span and representation. +fn self_ty_kind_for_diagnostic(ty: &rustc_hir::Ty<'_>, tcx: TyCtxt<'_>) -> (Span, String) { + match ty.kind { + TyKind::Path(QPath::Resolved(_, ty_path)) => ( + path_span_without_args(ty_path), + ty_path + .res + .opt_def_id() + .map(|did| tcx.opt_item_name(did)) + .flatten() + .as_ref() + .map(|s| Symbol::as_str(s)) + .unwrap_or("<unnameable>") + .to_string(), + ), + TyKind::TraitObject([principle_poly_trait_ref, ..], _, _) => { + let path = &principle_poly_trait_ref.trait_ref.path; + ( + path_span_without_args(path), + path.res + .opt_def_id() + .map(|did| tcx.opt_item_name(did)) + .flatten() + .as_ref() + .map(|s| Symbol::as_str(s)) + .unwrap_or("<unnameable>") + .to_string(), + ) + } + _ => (ty.span, rustc_hir_pretty::ty_to_string(&tcx, ty)), + } +} |