1 //! Implementation of lint checking.
3 //! The lint checking is mostly consolidated into one pass which runs
4 //! after all other analyses. Throughout compilation, lint warnings
5 //! can be added via the `add_lint` method on the Session structure. This
6 //! requires a span and an ID of the node that the lint is being added to. The
7 //! lint isn't actually emitted at that time because it is unknown what the
8 //! actual lint level at that location is.
10 //! To actually emit lint warnings/errors, a separate pass is used.
11 //! A context keeps track of the current state of all lint levels.
12 //! Upon entering a node of the ast which can modify the lint settings, the
13 //! previous lint state is pushed onto a stack and the ast is then recursed
14 //! upon. As the ast is traversed, this keeps track of the current lint level
15 //! for all lint attributes.
17 use self::TargetLint::*;
19 use crate::levels::LintLevelsBuilder;
20 use crate::passes::{EarlyLintPassObject, LateLintPassObject};
22 use rustc_ast::util::lev_distance::find_best_match_for_name;
23 use rustc_data_structures::fx::FxHashMap;
24 use rustc_data_structures::sync;
25 use rustc_errors::{struct_span_err, Applicability};
27 use rustc_hir::def::Res;
28 use rustc_hir::def_id::{CrateNum, DefId};
29 use rustc_hir::definitions::{DefPathData, DisambiguatedDefPathData};
30 use rustc_middle::lint::LintDiagnosticBuilder;
31 use rustc_middle::middle::privacy::AccessLevels;
32 use rustc_middle::middle::stability;
33 use rustc_middle::ty::layout::{LayoutError, TyAndLayout};
34 use rustc_middle::ty::print::with_no_trimmed_paths;
35 use rustc_middle::ty::{self, print::Printer, subst::GenericArg, Ty, TyCtxt};
36 use rustc_session::lint::{add_elided_lifetime_in_path_suggestion, BuiltinLintDiagnostics};
37 use rustc_session::lint::{FutureIncompatibleInfo, Level, Lint, LintBuffer, LintId};
38 use rustc_session::Session;
39 use rustc_span::{symbol::Symbol, MultiSpan, Span, DUMMY_SP};
40 use rustc_target::abi::LayoutOf;
45 /// Information about the registered lints.
47 /// This is basically the subset of `Context` that we can
48 /// build early in the compile pipeline.
49 pub struct LintStore {
51 lints: Vec<&'static Lint>,
53 /// Constructor functions for each variety of lint pass.
55 /// These should only be called once, but since we want to avoid locks or
56 /// interior mutability, we don't enforce this (and lints should, in theory,
57 /// be compatible with being constructed more than once, though not
58 /// necessarily in a sane manner. This is safe though.)
59 pub pre_expansion_passes: Vec<Box<dyn Fn() -> EarlyLintPassObject + sync::Send + sync::Sync>>,
60 pub early_passes: Vec<Box<dyn Fn() -> EarlyLintPassObject + sync::Send + sync::Sync>>,
61 pub late_passes: Vec<Box<dyn Fn() -> LateLintPassObject + sync::Send + sync::Sync>>,
62 /// This is unique in that we construct them per-module, so not once.
63 pub late_module_passes: Vec<Box<dyn Fn() -> LateLintPassObject + sync::Send + sync::Sync>>,
65 /// Lints indexed by name.
66 by_name: FxHashMap<String, TargetLint>,
68 /// Map of registered lint groups to what lints they expand to.
69 lint_groups: FxHashMap<&'static str, LintGroup>,
72 /// The target of the `by_name` map, which accounts for renaming/deprecation.
74 /// A direct lint target
77 /// Temporary renaming, used for easing migration pain; see #16545
78 Renamed(String, LintId),
80 /// Lint with this name existed previously, but has been removed/deprecated.
81 /// The string argument is the reason for removal.
85 pub enum FindLintError {
92 /// Whether deprecation warnings should be suppressed for this alias.
97 lint_ids: Vec<LintId>,
99 depr: Option<LintAlias>,
102 pub enum CheckLintNameResult<'a> {
104 /// Lint doesn't exist. Potentially contains a suggestion for a correct lint name.
105 NoLint(Option<Symbol>),
106 /// The lint is either renamed or removed. This is the warning
107 /// message, and an optional new name (`None` if removed).
108 Warning(String, Option<String>),
109 /// The lint is from a tool. If the Option is None, then either
110 /// the lint does not exist in the tool or the code was not
111 /// compiled with the tool and therefore the lint was never
112 /// added to the `LintStore`. Otherwise the `LintId` will be
113 /// returned as if it where a rustc lint.
114 Tool(Result<&'a [LintId], (Option<&'a [LintId]>, String)>),
118 pub fn new() -> LintStore {
121 pre_expansion_passes: vec![],
122 early_passes: vec![],
124 late_module_passes: vec![],
125 by_name: Default::default(),
126 lint_groups: Default::default(),
130 pub fn get_lints<'t>(&'t self) -> &'t [&'static Lint] {
134 pub fn get_lint_groups<'t>(&'t self) -> Vec<(&'static str, Vec<LintId>, bool)> {
137 .filter(|(_, LintGroup { depr, .. })| {
138 // Don't display deprecated lint groups.
141 .map(|(k, LintGroup { lint_ids, from_plugin, .. })| {
142 (*k, lint_ids.clone(), *from_plugin)
147 pub fn register_early_pass(
149 pass: impl Fn() -> EarlyLintPassObject + 'static + sync::Send + sync::Sync,
151 self.early_passes.push(Box::new(pass));
154 pub fn register_pre_expansion_pass(
156 pass: impl Fn() -> EarlyLintPassObject + 'static + sync::Send + sync::Sync,
158 self.pre_expansion_passes.push(Box::new(pass));
161 pub fn register_late_pass(
163 pass: impl Fn() -> LateLintPassObject + 'static + sync::Send + sync::Sync,
165 self.late_passes.push(Box::new(pass));
168 pub fn register_late_mod_pass(
170 pass: impl Fn() -> LateLintPassObject + 'static + sync::Send + sync::Sync,
172 self.late_module_passes.push(Box::new(pass));
175 // Helper method for register_early/late_pass
176 pub fn register_lints(&mut self, lints: &[&'static Lint]) {
178 self.lints.push(lint);
180 let id = LintId::of(lint);
181 if self.by_name.insert(lint.name_lower(), Id(id)).is_some() {
182 bug!("duplicate specification of lint {}", lint.name_lower())
185 if let Some(FutureIncompatibleInfo { edition, .. }) = lint.future_incompatible {
186 if let Some(edition) = edition {
188 .entry(edition.lint_name())
189 .or_insert(LintGroup {
191 from_plugin: lint.is_plugin,
199 .entry("future_incompatible")
200 .or_insert(LintGroup {
202 from_plugin: lint.is_plugin,
211 pub fn register_group_alias(&mut self, lint_name: &'static str, alias: &'static str) {
212 self.lint_groups.insert(
217 depr: Some(LintAlias { name: lint_name, silent: true }),
222 pub fn register_group(
226 deprecated_name: Option<&'static str>,
231 .insert(name, LintGroup { lint_ids: to, from_plugin, depr: None })
233 if let Some(deprecated) = deprecated_name {
234 self.lint_groups.insert(
239 depr: Some(LintAlias { name, silent: false }),
245 bug!("duplicate specification of lint group {}", name);
249 pub fn register_renamed(&mut self, old_name: &str, new_name: &str) {
250 let target = match self.by_name.get(new_name) {
251 Some(&Id(lint_id)) => lint_id,
252 _ => bug!("invalid lint renaming of {} to {}", old_name, new_name),
254 self.by_name.insert(old_name.to_string(), Renamed(new_name.to_string(), target));
257 pub fn register_removed(&mut self, name: &str, reason: &str) {
258 self.by_name.insert(name.into(), Removed(reason.into()));
261 pub fn find_lints(&self, mut lint_name: &str) -> Result<Vec<LintId>, FindLintError> {
262 match self.by_name.get(lint_name) {
263 Some(&Id(lint_id)) => Ok(vec![lint_id]),
264 Some(&Renamed(_, lint_id)) => Ok(vec![lint_id]),
265 Some(&Removed(_)) => Err(FindLintError::Removed),
267 return match self.lint_groups.get(lint_name) {
268 Some(LintGroup { lint_ids, depr, .. }) => {
269 if let Some(LintAlias { name, .. }) = depr {
275 None => Err(FindLintError::Removed),
281 /// Checks the validity of lint names derived from the command line
282 pub fn check_lint_name_cmdline(&self, sess: &Session, lint_name: &str, level: Level) {
283 let db = match self.check_lint_name(lint_name, None) {
284 CheckLintNameResult::Ok(_) => None,
285 CheckLintNameResult::Warning(ref msg, _) => Some(sess.struct_warn(msg)),
286 CheckLintNameResult::NoLint(suggestion) => {
288 struct_span_err!(sess, DUMMY_SP, E0602, "unknown lint: `{}`", lint_name);
290 if let Some(suggestion) = suggestion {
291 err.help(&format!("did you mean: `{}`", suggestion));
296 CheckLintNameResult::Tool(result) => match result {
297 Err((Some(_), new_name)) => Some(sess.struct_warn(&format!(
298 "lint name `{}` is deprecated \
299 and does not have an effect anymore. \
307 if let Some(mut db) = db {
309 "requested on the command line with `{} {}`",
311 Level::Allow => "-A",
314 Level::Forbid => "-F",
323 /// Checks the name of a lint for its existence, and whether it was
324 /// renamed or removed. Generates a DiagnosticBuilder containing a
325 /// warning for renamed and removed lints. This is over both lint
326 /// names from attributes and those passed on the command line. Since
327 /// it emits non-fatal warnings and there are *two* lint passes that
328 /// inspect attributes, this is only run from the late pass to avoid
329 /// printing duplicate warnings.
330 pub fn check_lint_name(
333 tool_name: Option<Symbol>,
334 ) -> CheckLintNameResult<'_> {
335 let complete_name = if let Some(tool_name) = tool_name {
336 format!("{}::{}", tool_name, lint_name)
338 lint_name.to_string()
340 // If the lint was scoped with `tool::` check if the tool lint exists
341 if tool_name.is_some() {
342 match self.by_name.get(&complete_name) {
343 None => match self.lint_groups.get(&*complete_name) {
344 None => return CheckLintNameResult::Tool(Err((None, String::new()))),
345 Some(LintGroup { lint_ids, .. }) => {
346 return CheckLintNameResult::Tool(Ok(&lint_ids));
349 Some(&Id(ref id)) => return CheckLintNameResult::Tool(Ok(slice::from_ref(id))),
350 // If the lint was registered as removed or renamed by the lint tool, we don't need
351 // to treat tool_lints and rustc lints different and can use the code below.
355 match self.by_name.get(&complete_name) {
356 Some(&Renamed(ref new_name, _)) => CheckLintNameResult::Warning(
357 format!("lint `{}` has been renamed to `{}`", complete_name, new_name),
358 Some(new_name.to_owned()),
360 Some(&Removed(ref reason)) => CheckLintNameResult::Warning(
361 format!("lint `{}` has been removed: `{}`", complete_name, reason),
364 None => match self.lint_groups.get(&*complete_name) {
365 // If neither the lint, nor the lint group exists check if there is a `clippy::`
366 // variant of this lint
367 None => self.check_tool_name_for_backwards_compat(&complete_name, "clippy"),
368 Some(LintGroup { lint_ids, depr, .. }) => {
369 // Check if the lint group name is deprecated
370 if let Some(LintAlias { name, silent }) = depr {
371 let LintGroup { lint_ids, .. } = self.lint_groups.get(name).unwrap();
373 CheckLintNameResult::Ok(&lint_ids)
375 CheckLintNameResult::Tool(Err((Some(&lint_ids), (*name).to_string())))
378 CheckLintNameResult::Ok(&lint_ids)
381 Some(&Id(ref id)) => CheckLintNameResult::Ok(slice::from_ref(id)),
385 fn check_tool_name_for_backwards_compat(
389 ) -> CheckLintNameResult<'_> {
390 let complete_name = format!("{}::{}", tool_name, lint_name);
391 match self.by_name.get(&complete_name) {
392 None => match self.lint_groups.get(&*complete_name) {
393 // Now we are sure, that this lint exists nowhere
396 self.by_name.keys().map(|name| Symbol::intern(&name)).collect::<Vec<_>>();
398 let suggestion = find_best_match_for_name(
400 Symbol::intern(&lint_name.to_lowercase()),
404 CheckLintNameResult::NoLint(suggestion)
406 Some(LintGroup { lint_ids, depr, .. }) => {
407 // Reaching this would be weird, but let's cover this case anyway
408 if let Some(LintAlias { name, silent }) = depr {
409 let LintGroup { lint_ids, .. } = self.lint_groups.get(name).unwrap();
411 CheckLintNameResult::Tool(Err((Some(&lint_ids), complete_name)))
413 CheckLintNameResult::Tool(Err((Some(&lint_ids), (*name).to_string())))
416 CheckLintNameResult::Tool(Err((Some(&lint_ids), complete_name)))
419 Some(&Id(ref id)) => {
420 CheckLintNameResult::Tool(Err((Some(slice::from_ref(id)), complete_name)))
422 _ => CheckLintNameResult::NoLint(None),
427 /// Context for lint checking after type checking.
428 pub struct LateContext<'tcx> {
429 /// Type context we're checking in.
430 pub tcx: TyCtxt<'tcx>,
432 /// Current body, or `None` if outside a body.
433 pub enclosing_body: Option<hir::BodyId>,
435 /// Type-checking results for the current body. Access using the `typeck_results`
436 /// and `maybe_typeck_results` methods, which handle querying the typeck results on demand.
437 // FIXME(eddyb) move all the code accessing internal fields like this,
438 // to this module, to avoid exposing it to lint logic.
439 pub(super) cached_typeck_results: Cell<Option<&'tcx ty::TypeckResults<'tcx>>>,
441 /// Parameter environment for the item we are in.
442 pub param_env: ty::ParamEnv<'tcx>,
444 /// Items accessible from the crate being checked.
445 pub access_levels: &'tcx AccessLevels,
447 /// The store of registered lints and the lint levels.
448 pub lint_store: &'tcx LintStore,
450 pub last_node_with_lint_attrs: hir::HirId,
452 /// Generic type parameters in scope for the item we are in.
453 pub generics: Option<&'tcx hir::Generics<'tcx>>,
455 /// We are only looking at one module
456 pub only_module: bool,
459 /// Context for lint checking of the AST, after expansion, before lowering to
461 pub struct EarlyContext<'a> {
462 /// Type context we're checking in.
463 pub sess: &'a Session,
465 /// The crate being checked.
466 pub krate: &'a ast::Crate,
468 pub builder: LintLevelsBuilder<'a>,
470 /// The store of registered lints and the lint levels.
471 pub lint_store: &'a LintStore,
473 pub buffered: LintBuffer,
476 pub trait LintPassObject: Sized {}
478 impl LintPassObject for EarlyLintPassObject {}
480 impl LintPassObject for LateLintPassObject {}
482 pub trait LintContext: Sized {
483 type PassObject: LintPassObject;
485 fn sess(&self) -> &Session;
486 fn lints(&self) -> &LintStore;
488 fn lookup_with_diagnostics(
491 span: Option<impl Into<MultiSpan>>,
492 decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>),
493 diagnostic: BuiltinLintDiagnostics,
495 self.lookup(lint, span, |lint| {
496 // We first generate a blank diagnostic.
497 let mut db = lint.build("");
499 // Now, set up surrounding context.
500 let sess = self.sess();
502 BuiltinLintDiagnostics::Normal => (),
503 BuiltinLintDiagnostics::BareTraitObject(span, is_global) => {
504 let (sugg, app) = match sess.source_map().span_to_snippet(span) {
505 Ok(s) if is_global => {
506 (format!("dyn ({})", s), Applicability::MachineApplicable)
508 Ok(s) => (format!("dyn {}", s), Applicability::MachineApplicable),
509 Err(_) => ("dyn <type>".to_string(), Applicability::HasPlaceholders),
511 db.span_suggestion(span, "use `dyn`", sugg, app);
513 BuiltinLintDiagnostics::AbsPathWithModule(span) => {
514 let (sugg, app) = match sess.source_map().span_to_snippet(span) {
516 // FIXME(Manishearth) ideally the emitting code
517 // can tell us whether or not this is global
519 if s.trim_start().starts_with("::") { "" } else { "::" };
521 (format!("crate{}{}", opt_colon, s), Applicability::MachineApplicable)
523 Err(_) => ("crate::<path>".to_string(), Applicability::HasPlaceholders),
525 db.span_suggestion(span, "use `crate`", sugg, app);
527 BuiltinLintDiagnostics::ProcMacroDeriveResolutionFallback(span) => {
530 "names from parent modules are not accessible without an explicit import",
533 BuiltinLintDiagnostics::MacroExpandedMacroExportsAccessedByAbsolutePaths(
536 db.span_note(span_def, "the macro is defined here");
538 BuiltinLintDiagnostics::ElidedLifetimesInPaths(
545 add_elided_lifetime_in_path_suggestion(
555 BuiltinLintDiagnostics::UnknownCrateTypes(span, note, sugg) => {
556 db.span_suggestion(span, ¬e, sugg, Applicability::MaybeIncorrect);
558 BuiltinLintDiagnostics::UnusedImports(message, replaces) => {
559 if !replaces.is_empty() {
560 db.tool_only_multipart_suggestion(
563 Applicability::MachineApplicable,
567 BuiltinLintDiagnostics::RedundantImport(spans, ident) => {
568 for (span, is_imported) in spans {
569 let introduced = if is_imported { "imported" } else { "defined" };
572 format!("the item `{}` is already {} here", ident, introduced),
576 BuiltinLintDiagnostics::DeprecatedMacro(suggestion, span) => {
577 stability::deprecation_suggestion(&mut db, "macro", suggestion, span)
579 BuiltinLintDiagnostics::UnusedDocComment(span) => {
580 db.span_label(span, "rustdoc does not generate documentation for macro invocations");
581 db.help("to document an item produced by a macro, \
582 the macro must produce the documentation as part of its expansion");
585 // Rewrap `db`, and pass control to the user.
586 decorate(LintDiagnosticBuilder::new(db));
590 // FIXME: These methods should not take an Into<MultiSpan> -- instead, callers should need to
591 // set the span in their `decorate` function (preferably using set_span).
592 fn lookup<S: Into<MultiSpan>>(
596 decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>),
599 fn struct_span_lint<S: Into<MultiSpan>>(
603 decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>),
605 self.lookup(lint, Some(span), decorate);
607 /// Emit a lint at the appropriate level, with no associated span.
608 fn lint(&self, lint: &'static Lint, decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>)) {
609 self.lookup(lint, None as Option<Span>, decorate);
613 impl<'a> EarlyContext<'a> {
616 lint_store: &'a LintStore,
617 krate: &'a ast::Crate,
618 buffered: LintBuffer,
619 warn_about_weird_lints: bool,
620 ) -> EarlyContext<'a> {
625 builder: LintLevelsBuilder::new(sess, warn_about_weird_lints, lint_store),
631 impl LintContext for LateContext<'_> {
632 type PassObject = LateLintPassObject;
634 /// Gets the overall compiler `Session` object.
635 fn sess(&self) -> &Session {
639 fn lints(&self) -> &LintStore {
643 fn lookup<S: Into<MultiSpan>>(
647 decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>),
649 let hir_id = self.last_node_with_lint_attrs;
652 Some(s) => self.tcx.struct_span_lint_hir(lint, hir_id, s, decorate),
653 None => self.tcx.struct_lint_node(lint, hir_id, decorate),
658 impl LintContext for EarlyContext<'_> {
659 type PassObject = EarlyLintPassObject;
661 /// Gets the overall compiler `Session` object.
662 fn sess(&self) -> &Session {
666 fn lints(&self) -> &LintStore {
670 fn lookup<S: Into<MultiSpan>>(
674 decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>),
676 self.builder.struct_lint(lint, span.map(|s| s.into()), decorate)
680 impl<'tcx> LateContext<'tcx> {
681 /// Gets the type-checking results for the current body,
682 /// or `None` if outside a body.
683 pub fn maybe_typeck_results(&self) -> Option<&'tcx ty::TypeckResults<'tcx>> {
684 self.cached_typeck_results.get().or_else(|| {
685 self.enclosing_body.map(|body| {
686 let typeck_results = self.tcx.typeck_body(body);
687 self.cached_typeck_results.set(Some(typeck_results));
693 /// Gets the type-checking results for the current body.
694 /// As this will ICE if called outside bodies, only call when working with
695 /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
697 pub fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
698 self.maybe_typeck_results().expect("`LateContext::typeck_results` called outside of body")
701 /// Returns the final resolution of a `QPath`, or `Res::Err` if unavailable.
702 /// Unlike `.typeck_results().qpath_res(qpath, id)`, this can be used even outside
703 /// bodies (e.g. for paths in `hir::Ty`), without any risk of ICE-ing.
704 pub fn qpath_res(&self, qpath: &hir::QPath<'_>, id: hir::HirId) -> Res {
706 hir::QPath::Resolved(_, ref path) => path.res,
707 hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
708 .maybe_typeck_results()
709 .and_then(|typeck_results| typeck_results.type_dependent_def(id))
710 .map_or(Res::Err, |(kind, def_id)| Res::Def(kind, def_id)),
714 /// Check if a `DefId`'s path matches the given absolute type path usage.
716 /// Anonymous scopes such as `extern` imports are matched with `kw::Invalid`;
717 /// inherent `impl` blocks are matched with the name of the type.
719 /// Instead of using this method, it is often preferable to instead use
720 /// `rustc_diagnostic_item` or a `lang_item`. This is less prone to errors
721 /// as paths get invalidated if the target definition moves.
725 /// ```rust,ignore (no context or def id available)
726 /// if cx.match_def_path(def_id, &[sym::core, sym::option, sym::Option]) {
727 /// // The given `def_id` is that of an `Option` type
730 pub fn match_def_path(&self, def_id: DefId, path: &[Symbol]) -> bool {
731 let names = self.get_def_path(def_id);
733 names.len() == path.len() && names.into_iter().zip(path.iter()).all(|(a, &b)| a == b)
736 /// Gets the absolute path of `def_id` as a vector of `Symbol`.
740 /// ```rust,ignore (no context or def id available)
741 /// let def_path = cx.get_def_path(def_id);
742 /// if let &[sym::core, sym::option, sym::Option] = &def_path[..] {
743 /// // The given `def_id` is that of an `Option` type
746 pub fn get_def_path(&self, def_id: DefId) -> Vec<Symbol> {
747 pub struct AbsolutePathPrinter<'tcx> {
748 pub tcx: TyCtxt<'tcx>,
751 impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
754 type Path = Vec<Symbol>;
757 type DynExistential = ();
760 fn tcx(&self) -> TyCtxt<'tcx> {
764 fn print_region(self, _region: ty::Region<'_>) -> Result<Self::Region, Self::Error> {
768 fn print_type(self, _ty: Ty<'tcx>) -> Result<Self::Type, Self::Error> {
772 fn print_dyn_existential(
774 _predicates: &'tcx ty::List<ty::ExistentialPredicate<'tcx>>,
775 ) -> Result<Self::DynExistential, Self::Error> {
779 fn print_const(self, _ct: &'tcx ty::Const<'tcx>) -> Result<Self::Const, Self::Error> {
783 fn path_crate(self, cnum: CrateNum) -> Result<Self::Path, Self::Error> {
784 Ok(vec![self.tcx.original_crate_name(cnum)])
790 trait_ref: Option<ty::TraitRef<'tcx>>,
791 ) -> Result<Self::Path, Self::Error> {
792 if trait_ref.is_none() {
793 if let ty::Adt(def, substs) = self_ty.kind() {
794 return self.print_def_path(def.did, substs);
798 // This shouldn't ever be needed, but just in case:
799 with_no_trimmed_paths(|| {
800 Ok(vec![match trait_ref {
801 Some(trait_ref) => Symbol::intern(&format!("{:?}", trait_ref)),
802 None => Symbol::intern(&format!("<{}>", self_ty)),
809 print_prefix: impl FnOnce(Self) -> Result<Self::Path, Self::Error>,
810 _disambiguated_data: &DisambiguatedDefPathData,
812 trait_ref: Option<ty::TraitRef<'tcx>>,
813 ) -> Result<Self::Path, Self::Error> {
814 let mut path = print_prefix(self)?;
816 // This shouldn't ever be needed, but just in case:
817 path.push(match trait_ref {
818 Some(trait_ref) => with_no_trimmed_paths(|| {
819 Symbol::intern(&format!(
821 trait_ref.print_only_trait_path(),
826 with_no_trimmed_paths(|| Symbol::intern(&format!("<impl {}>", self_ty)))
835 print_prefix: impl FnOnce(Self) -> Result<Self::Path, Self::Error>,
836 disambiguated_data: &DisambiguatedDefPathData,
837 ) -> Result<Self::Path, Self::Error> {
838 let mut path = print_prefix(self)?;
840 // Skip `::{{constructor}}` on tuple/unit structs.
841 if let DefPathData::Ctor = disambiguated_data.data {
845 path.push(Symbol::intern(&disambiguated_data.data.to_string()));
849 fn path_generic_args(
851 print_prefix: impl FnOnce(Self) -> Result<Self::Path, Self::Error>,
852 _args: &[GenericArg<'tcx>],
853 ) -> Result<Self::Path, Self::Error> {
858 AbsolutePathPrinter { tcx: self.tcx }.print_def_path(def_id, &[]).unwrap()
862 impl<'tcx> LayoutOf for LateContext<'tcx> {
864 type TyAndLayout = Result<TyAndLayout<'tcx>, LayoutError<'tcx>>;
866 fn layout_of(&self, ty: Ty<'tcx>) -> Self::TyAndLayout {
867 self.tcx.layout_of(self.param_env.and(ty))