1 use crate::hir::def_id::DefId;
2 use crate::hir::map::definitions::DefPathData;
3 use crate::middle::region;
4 use crate::ty::subst::{self, Subst, SubstsRef};
5 use crate::ty::{BrAnon, BrEnv, BrFresh, BrNamed};
6 use crate::ty::{Bool, Char, Adt};
7 use crate::ty::{Error, Str, Array, Slice, Float, FnDef, FnPtr};
8 use crate::ty::{Param, Bound, RawPtr, Ref, Never, Tuple};
9 use crate::ty::{Closure, Generator, GeneratorWitness, Foreign, Projection, Opaque};
10 use crate::ty::{Placeholder, UnnormalizedProjection, Dynamic, Int, Uint, Infer};
11 use crate::ty::{self, Ty, TyCtxt, TypeFoldable, GenericParamCount, GenericParamDefKind, ParamConst};
12 use crate::mir::interpret::ConstValue;
13 use crate::util::nodemap::FxHashSet;
19 use rustc_target::spec::abi::Abi;
20 use syntax::ast::CRATE_NODE_ID;
21 use syntax::symbol::{Symbol, InternedString};
24 /// The "region highlights" are used to control region printing during
25 /// specific error messages. When a "region highlight" is enabled, it
26 /// gives an alternate way to print specific regions. For now, we
27 /// always print those regions using a number, so something like "`'0`".
29 /// Regions not selected by the region highlight mode are presently
31 #[derive(Copy, Clone, Default)]
32 pub struct RegionHighlightMode {
33 /// If enabled, when we see the selected region, use "`'N`"
34 /// instead of the ordinary behavior.
35 highlight_regions: [Option<(ty::RegionKind, usize)>; 3],
37 /// If enabled, when printing a "free region" that originated from
38 /// the given `ty::BoundRegion`, print it as "`'1`". Free regions that would ordinarily
39 /// have names print as normal.
41 /// This is used when you have a signature like `fn foo(x: &u32,
42 /// y: &'a u32)` and we want to give a name to the region of the
44 highlight_bound_region: Option<(ty::BoundRegion, usize)>,
48 /// Mechanism for highlighting of specific regions for display in NLL region inference errors.
49 /// Contains region to highlight and counter for number to use when highlighting.
50 static REGION_HIGHLIGHT_MODE: Cell<RegionHighlightMode> =
51 Cell::new(RegionHighlightMode::default())
54 impl RegionHighlightMode {
55 /// Reads and returns the current region highlight settings (accesses thread-local state).
56 pub fn get() -> Self {
57 REGION_HIGHLIGHT_MODE.with(|c| c.get())
60 // Internal helper to update current settings during the execution of `op`.
64 op: impl FnOnce() -> R,
66 REGION_HIGHLIGHT_MODE.with(|c| {
74 /// If `region` and `number` are both `Some`, invokes
75 /// `highlighting_region`; otherwise, just invokes `op` directly.
76 pub fn maybe_highlighting_region<R>(
77 region: Option<ty::Region<'_>>,
78 number: Option<usize>,
79 op: impl FnOnce() -> R,
81 if let Some(k) = region {
82 if let Some(n) = number {
83 return Self::highlighting_region(k, n, op);
90 /// During the execution of `op`, highlights the region inference
91 /// variable `vid` as `'N`. We can only highlight one region `vid`
93 pub fn highlighting_region<R>(
94 region: ty::Region<'_>,
96 op: impl FnOnce() -> R,
98 let old_mode = Self::get();
99 let mut new_mode = old_mode;
100 let first_avail_slot = new_mode.highlight_regions.iter_mut()
101 .filter(|s| s.is_none())
105 "can only highlight {} placeholders at a time",
106 old_mode.highlight_regions.len(),
109 *first_avail_slot = Some((*region, number));
110 Self::set(old_mode, new_mode, op)
113 /// Convenience wrapper for `highlighting_region`.
114 pub fn highlighting_region_vid<R>(
117 op: impl FnOnce() -> R,
119 Self::highlighting_region(&ty::ReVar(vid), number, op)
122 /// Returns `true` if any placeholders are highlighted, and `false` otherwise.
123 fn any_region_vids_highlighted(&self) -> bool {
128 Some((ty::ReVar(_), _)) => true,
133 /// Returns `Some(n)` with the number to use for the given region, if any.
134 fn region_highlighted(&self, region: ty::Region<'_>) -> Option<usize> {
138 .filter_map(|h| match h {
139 Some((r, n)) if r == region => Some(*n),
145 /// During the execution of `op`, highlight the given bound
146 /// region. We can only highlight one bound region at a time. See
147 /// the field `highlight_bound_region` for more detailed notes.
148 pub fn highlighting_bound_region<R>(
151 op: impl FnOnce() -> R,
153 let old_mode = Self::get();
154 assert!(old_mode.highlight_bound_region.is_none());
158 highlight_bound_region: Some((br, number)),
165 /// Returns `true` if any placeholders are highlighted, and `false` otherwise.
166 pub fn any_placeholders_highlighted(&self) -> bool {
171 Some((ty::RePlaceholder(_), _)) => true,
176 /// Returns `Some(N)` if the placeholder `p` is highlighted to print as "`'N`".
177 pub fn placeholder_highlight(&self, p: ty::PlaceholderRegion) -> Option<usize> {
178 self.region_highlighted(&ty::RePlaceholder(p))
182 macro_rules! gen_display_debug_body {
184 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
185 let mut cx = PrintContext::new();
186 $with(self, f, &mut cx)
190 macro_rules! gen_display_debug {
191 ( ($($x:tt)+) $target:ty, display yes ) => {
192 impl<$($x)+> fmt::Display for $target {
193 gen_display_debug_body! { Print::print_display }
196 ( () $target:ty, display yes ) => {
197 impl fmt::Display for $target {
198 gen_display_debug_body! { Print::print_display }
201 ( ($($x:tt)+) $target:ty, debug yes ) => {
202 impl<$($x)+> fmt::Debug for $target {
203 gen_display_debug_body! { Print::print_debug }
206 ( () $target:ty, debug yes ) => {
207 impl fmt::Debug for $target {
208 gen_display_debug_body! { Print::print_debug }
211 ( $generic:tt $target:ty, $t:ident no ) => {};
213 macro_rules! gen_print_impl {
214 ( ($($x:tt)+) $target:ty, ($self:ident, $f:ident, $cx:ident) $disp:block $dbg:block ) => {
215 impl<$($x)+> Print for $target {
216 fn print<F: fmt::Write>(&$self, $f: &mut F, $cx: &mut PrintContext) -> fmt::Result {
222 ( () $target:ty, ($self:ident, $f:ident, $cx:ident) $disp:block $dbg:block ) => {
223 impl Print for $target {
224 fn print<F: fmt::Write>(&$self, $f: &mut F, $cx: &mut PrintContext) -> fmt::Result {
230 ( $generic:tt $target:ty,
231 $vars:tt $gendisp:ident $disp:block $gendbg:ident $dbg:block ) => {
232 gen_print_impl! { $generic $target, $vars $disp $dbg }
233 gen_display_debug! { $generic $target, display $gendisp }
234 gen_display_debug! { $generic $target, debug $gendbg }
237 macro_rules! define_print {
238 ( $generic:tt $target:ty,
239 $vars:tt { display $disp:block debug $dbg:block } ) => {
240 gen_print_impl! { $generic $target, $vars yes $disp yes $dbg }
242 ( $generic:tt $target:ty,
243 $vars:tt { debug $dbg:block display $disp:block } ) => {
244 gen_print_impl! { $generic $target, $vars yes $disp yes $dbg }
246 ( $generic:tt $target:ty,
247 $vars:tt { debug $dbg:block } ) => {
248 gen_print_impl! { $generic $target, $vars no {
249 bug!(concat!("display not implemented for ", stringify!($target)));
252 ( $generic:tt $target:ty,
253 ($self:ident, $f:ident, $cx:ident) { display $disp:block } ) => {
254 gen_print_impl! { $generic $target, ($self, $f, $cx) yes $disp no {
255 write!($f, "{:?}", $self)
259 macro_rules! define_print_multi {
260 ( [ $($generic:tt $target:ty),* ] $vars:tt $def:tt ) => {
261 $(define_print! { $generic $target, $vars $def })*
264 macro_rules! print_inner {
265 ( $f:expr, $cx:expr, write ($($data:expr),+) ) => {
266 write!($f, $($data),+)
268 ( $f:expr, $cx:expr, $kind:ident ($data:expr) ) => {
273 ( $f:expr, $cx:expr $(, $kind:ident $data:tt)+ ) => {
274 Ok(())$(.and_then(|_| print_inner!($f, $cx, $kind $data)))+
279 struct LateBoundRegionNameCollector(FxHashSet<InternedString>);
280 impl<'tcx> ty::fold::TypeVisitor<'tcx> for LateBoundRegionNameCollector {
281 fn visit_region(&mut self, r: ty::Region<'tcx>) -> bool {
283 ty::ReLateBound(_, ty::BrNamed(_, name)) => {
288 r.super_visit_with(self)
293 pub struct PrintContext {
296 identify_regions: bool,
297 used_region_names: Option<FxHashSet<InternedString>>,
303 ty::tls::with_opt(|tcx| {
304 let (is_verbose, identify_regions) = tcx.map(
305 |tcx| (tcx.sess.verbose(), tcx.sess.opts.debugging_opts.identify_regions)
306 ).unwrap_or((false, false));
309 is_verbose: is_verbose,
310 identify_regions: identify_regions,
311 used_region_names: None,
317 fn prepare_late_bound_region_info<'tcx, T>(&mut self, value: &ty::Binder<T>)
318 where T: TypeFoldable<'tcx>
320 let mut collector = LateBoundRegionNameCollector(Default::default());
321 value.visit_with(&mut collector);
322 self.used_region_names = Some(collector.0);
323 self.region_index = 0;
328 fn print<F: fmt::Write>(&self, f: &mut F, cx: &mut PrintContext) -> fmt::Result;
329 fn print_to_string(&self, cx: &mut PrintContext) -> String {
330 let mut result = String::new();
331 let _ = self.print(&mut result, cx);
334 fn print_display<F: fmt::Write>(&self, f: &mut F, cx: &mut PrintContext) -> fmt::Result {
335 let old_debug = cx.is_debug;
337 let result = self.print(f, cx);
338 cx.is_debug = old_debug;
341 fn print_display_to_string(&self, cx: &mut PrintContext) -> String {
342 let mut result = String::new();
343 let _ = self.print_display(&mut result, cx);
346 fn print_debug<F: fmt::Write>(&self, f: &mut F, cx: &mut PrintContext) -> fmt::Result {
347 let old_debug = cx.is_debug;
349 let result = self.print(f, cx);
350 cx.is_debug = old_debug;
353 fn print_debug_to_string(&self, cx: &mut PrintContext) -> String {
354 let mut result = String::new();
355 let _ = self.print_debug(&mut result, cx);
361 fn fn_sig<F: fmt::Write>(&mut self,
368 let mut inputs = inputs.iter();
369 if let Some(&ty) = inputs.next() {
370 print!(f, self, print_display(ty))?;
372 print!(f, self, write(", "), print_display(ty))?;
379 if !output.is_unit() {
380 print!(f, self, write(" -> "), print_display(output))?;
386 fn parameterized<F: fmt::Write>(&mut self,
388 substs: SubstsRef<'_>,
390 projections: &[ty::ProjectionPredicate<'_>])
392 let key = ty::tls::with(|tcx| tcx.def_key(did));
394 let verbose = self.is_verbose;
395 let mut num_supplied_defaults = 0;
396 let mut has_self = false;
397 let mut own_counts: GenericParamCount = Default::default();
398 let mut is_value_path = false;
399 let mut item_name = Some(key.disambiguated_data.data.as_interned_str());
400 let fn_trait_kind = ty::tls::with(|tcx| {
401 // Unfortunately, some kinds of items (e.g., closures) don't have
402 // generics. So walk back up the find the closest parent that DOES
404 let mut item_def_id = did;
406 let key = tcx.def_key(item_def_id);
407 match key.disambiguated_data.data {
408 DefPathData::AssocTypeInTrait(_) |
409 DefPathData::AssocTypeInImpl(_) |
410 DefPathData::AssocExistentialInImpl(_) |
411 DefPathData::Trait(_) |
412 DefPathData::TraitAlias(_) |
414 DefPathData::TypeNs(_) => {
417 DefPathData::ValueNs(_) |
418 DefPathData::EnumVariant(_) => {
419 is_value_path = true;
422 DefPathData::CrateRoot |
424 DefPathData::Module(_) |
425 DefPathData::MacroDef(_) |
426 DefPathData::ClosureExpr |
427 DefPathData::TypeParam(_) |
428 DefPathData::LifetimeParam(_) |
429 DefPathData::ConstParam(_) |
430 DefPathData::Field(_) |
431 DefPathData::StructCtor |
432 DefPathData::AnonConst |
433 DefPathData::ImplTrait |
434 DefPathData::GlobalMetaData(_) => {
435 // if we're making a symbol for something, there ought
436 // to be a value or type-def or something in there
438 item_def_id.index = key.parent.unwrap_or_else(|| {
439 bug!("finding type for {:?}, encountered def-id {:?} with no \
440 parent", did, item_def_id);
445 let mut generics = tcx.generics_of(item_def_id);
446 let child_own_counts = generics.own_counts();
447 let mut path_def_id = did;
448 has_self = generics.has_self;
450 let mut child_types = 0;
451 if let Some(def_id) = generics.parent {
453 assert!(is_value_path);
454 child_types = child_own_counts.types;
455 generics = tcx.generics_of(def_id);
456 own_counts = generics.own_counts();
459 print!(f, self, write("<"), print_display(substs.type_at(0)), write(" as "))?;
462 path_def_id = def_id;
468 assert_eq!(has_self, false);
471 own_counts = child_own_counts;
476 let mut type_params =
477 generics.params.iter().rev().filter_map(|param| match param.kind {
478 GenericParamDefKind::Lifetime => None,
479 GenericParamDefKind::Type { has_default, .. } => {
480 Some((param.def_id, has_default))
482 GenericParamDefKind::Const => None, // FIXME(const_generics:defaults)
485 let has_default = type_params.peek().map(|(_, has_default)| has_default);
486 *has_default.unwrap_or(&false)
489 if let Some(substs) = tcx.lift(&substs) {
490 let types = substs.types().rev().skip(child_types);
491 for ((def_id, has_default), actual) in type_params.zip(types) {
495 if tcx.type_of(def_id).subst(tcx, substs) != actual {
498 num_supplied_defaults += 1;
504 print!(f, self, write("{}", tcx.item_path_str(path_def_id)))?;
505 Ok(tcx.lang_items().fn_trait_kind(path_def_id))
508 if !verbose && fn_trait_kind.is_some() && projections.len() == 1 {
509 let projection_ty = projections[0].ty;
510 if let Tuple(ref args) = substs.type_at(1).sty {
511 return self.fn_sig(f, args, false, projection_ty);
515 let empty = Cell::new(true);
516 let start_or_continue = |f: &mut F, start: &str, cont: &str| {
519 write!(f, "{}", start)
521 write!(f, "{}", cont)
525 let print_regions = |f: &mut F, start: &str, skip, count| {
526 // Don't print any regions if they're all erased.
527 let regions = || substs.regions().skip(skip).take(count);
528 if regions().all(|r: ty::Region<'_>| *r == ty::ReErased) {
532 for region in regions() {
533 let region: ty::Region<'_> = region;
534 start_or_continue(f, start, ", ")?;
536 write!(f, "{:?}", region)?;
538 let s = region.to_string();
540 // This happens when the value of the region
541 // parameter is not easily serialized. This may be
542 // because the user omitted it in the first place,
543 // or because it refers to some block in the code,
544 // etc. I'm not sure how best to serialize this.
555 print_regions(f, "<", 0, own_counts.lifetimes)?;
557 let tps = substs.types()
558 .take(own_counts.types - num_supplied_defaults)
559 .skip(has_self as usize);
562 start_or_continue(f, "<", ", ")?;
563 ty.print_display(f, self)?;
566 for projection in projections {
567 start_or_continue(f, "<", ", ")?;
571 tcx.associated_item(projection.projection_ty.item_def_id).ident),
572 print_display(projection.ty))
576 // FIXME(const_generics::defaults)
577 let consts = substs.consts();
580 start_or_continue(f, "<", ", ")?;
581 ct.print_display(f, self)?;
584 start_or_continue(f, "", ">")?;
586 // For values, also print their name and type parameters.
594 if let Some(item_name) = item_name {
595 write!(f, "::{}", item_name)?;
598 print_regions(f, "::<", own_counts.lifetimes, usize::MAX)?;
600 // FIXME: consider being smart with defaults here too
601 for ty in substs.types().skip(own_counts.types) {
602 start_or_continue(f, "::<", ", ")?;
603 ty.print_display(f, self)?;
606 start_or_continue(f, "", ">")?;
612 fn in_binder<'a, 'gcx, 'tcx, T, U, F>(&mut self,
614 tcx: TyCtxt<'a, 'gcx, 'tcx>,
615 original: &ty::Binder<T>,
616 lifted: Option<ty::Binder<U>>) -> fmt::Result
617 where T: Print, U: Print + TypeFoldable<'tcx>, F: fmt::Write
619 fn name_by_region_index(index: usize) -> InternedString {
621 0 => Symbol::intern("'r"),
622 1 => Symbol::intern("'s"),
623 i => Symbol::intern(&format!("'t{}", i-2)),
627 // Replace any anonymous late-bound regions with named
628 // variants, using gensym'd identifiers, so that we can
629 // clearly differentiate between named and unnamed regions in
630 // the output. We'll probably want to tweak this over time to
631 // decide just how much information to give.
632 let value = if let Some(v) = lifted {
635 return original.skip_binder().print_display(f, self);
638 if self.binder_depth == 0 {
639 self.prepare_late_bound_region_info(&value);
642 let mut empty = true;
643 let mut start_or_continue = |f: &mut F, start: &str, cont: &str| {
646 write!(f, "{}", start)
648 write!(f, "{}", cont)
652 let old_region_index = self.region_index;
653 let mut region_index = old_region_index;
654 let new_value = tcx.replace_late_bound_regions(&value, |br| {
655 let _ = start_or_continue(f, "for<", ", ");
657 ty::BrNamed(_, name) => {
658 let _ = write!(f, "{}", name);
665 let name = name_by_region_index(region_index);
667 if !self.is_name_used(&name) {
671 let _ = write!(f, "{}", name);
672 ty::BrNamed(tcx.hir().local_def_id(CRATE_NODE_ID), name)
675 tcx.mk_region(ty::ReLateBound(ty::INNERMOST, br))
677 start_or_continue(f, "", "> ")?;
679 // Push current state to gcx, and restore after writing new_value.
680 self.binder_depth += 1;
681 self.region_index = region_index;
682 let result = new_value.print_display(f, self);
683 self.region_index = old_region_index;
684 self.binder_depth -= 1;
688 fn is_name_used(&self, name: &InternedString) -> bool {
689 match self.used_region_names {
690 Some(ref names) => names.contains(name),
696 pub fn verbose() -> bool {
697 ty::tls::with(|tcx| tcx.sess.verbose())
700 pub fn identify_regions() -> bool {
701 ty::tls::with(|tcx| tcx.sess.opts.debugging_opts.identify_regions)
704 pub fn parameterized<F: fmt::Write>(f: &mut F,
705 substs: SubstsRef<'_>,
707 projections: &[ty::ProjectionPredicate<'_>])
709 PrintContext::new().parameterized(f, substs, did, projections)
712 impl<'a, T: Print> Print for &'a T {
713 fn print<F: fmt::Write>(&self, f: &mut F, cx: &mut PrintContext) -> fmt::Result {
719 ('tcx) &'tcx ty::List<ty::ExistentialPredicate<'tcx>>, (self, f, cx) {
721 // Generate the main trait ref, including associated types.
722 ty::tls::with(|tcx| {
723 // Use a type that can't appear in defaults of type parameters.
724 let dummy_self = tcx.mk_infer(ty::FreshTy(0));
725 let mut first = true;
727 if let Some(principal) = self.principal() {
730 .expect("could not lift TraitRef for printing")
731 .with_self_ty(tcx, dummy_self);
732 let projections = self.projection_bounds().map(|p| {
734 .expect("could not lift projection for printing")
735 .with_self_ty(tcx, dummy_self)
736 }).collect::<Vec<_>>();
737 cx.parameterized(f, principal.substs, principal.def_id, &projections)?;
742 let mut auto_traits: Vec<_> = self.auto_traits().map(|did| {
743 tcx.item_path_str(did)
746 // The auto traits come ordered by `DefPathHash`. While
747 // `DefPathHash` is *stable* in the sense that it depends on
748 // neither the host nor the phase of the moon, it depends
749 // "pseudorandomly" on the compiler version and the target.
751 // To avoid that causing instabilities in compiletest
752 // output, sort the auto-traits alphabetically.
755 for auto_trait in auto_traits {
761 write!(f, "{}", auto_trait)?;
772 impl fmt::Debug for ty::GenericParamDef {
773 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
774 let type_name = match self.kind {
775 ty::GenericParamDefKind::Lifetime => "Lifetime",
776 ty::GenericParamDefKind::Type { .. } => "Type",
777 ty::GenericParamDefKind::Const => "Const",
779 write!(f, "{}({}, {:?}, {})",
787 impl fmt::Debug for ty::TraitDef {
788 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
789 ty::tls::with(|tcx| {
790 write!(f, "{}", tcx.item_path_str(self.def_id))
795 impl fmt::Debug for ty::AdtDef {
796 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
797 ty::tls::with(|tcx| {
798 write!(f, "{}", tcx.item_path_str(self.did))
803 impl<'tcx> fmt::Debug for ty::ClosureUpvar<'tcx> {
804 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
805 write!(f, "ClosureUpvar({:?},{:?})",
811 impl fmt::Debug for ty::UpvarId {
812 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
813 write!(f, "UpvarId({:?};`{}`;{:?})",
814 self.var_path.hir_id,
815 ty::tls::with(|tcx| tcx.hir().name_by_hir_id(self.var_path.hir_id)),
816 self.closure_expr_id)
820 impl<'tcx> fmt::Debug for ty::UpvarBorrow<'tcx> {
821 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
822 write!(f, "UpvarBorrow({:?}, {:?})",
823 self.kind, self.region)
828 ('tcx) &'tcx ty::List<Ty<'tcx>>, (self, f, cx) {
831 let mut tys = self.iter();
832 if let Some(&ty) = tys.next() {
833 print!(f, cx, print(ty))?;
835 print!(f, cx, write(", "), print(ty))?;
844 ('tcx) ty::TypeAndMut<'tcx>, (self, f, cx) {
847 write("{}", if self.mutbl == hir::MutMutable { "mut " } else { "" }),
854 ('tcx) ty::ExistentialTraitRef<'tcx>, (self, f, cx) {
856 cx.parameterized(f, self.substs, self.def_id, &[])
859 ty::tls::with(|tcx| {
860 let dummy_self = tcx.mk_infer(ty::FreshTy(0));
862 let trait_ref = *tcx.lift(&ty::Binder::bind(*self))
863 .expect("could not lift TraitRef for printing")
864 .with_self_ty(tcx, dummy_self).skip_binder();
865 cx.parameterized(f, trait_ref.substs, trait_ref.def_id, &[])
872 ('tcx) ty::adjustment::Adjustment<'tcx>, (self, f, cx) {
874 print!(f, cx, write("{:?} -> ", self.kind), print(self.target))
880 () ty::BoundRegion, (self, f, cx) {
883 return self.print_debug(f, cx);
886 if let Some((region, counter)) = RegionHighlightMode::get().highlight_bound_region {
889 BrNamed(_, name) => write!(f, "{}", name),
890 BrAnon(_) | BrFresh(_) | BrEnv => write!(f, "'{}", counter)
896 BrNamed(_, name) => write!(f, "{}", name),
897 BrAnon(_) | BrFresh(_) | BrEnv => Ok(())
902 BrAnon(n) => write!(f, "BrAnon({:?})", n),
903 BrFresh(n) => write!(f, "BrFresh({:?})", n),
904 BrNamed(did, name) => {
905 write!(f, "BrNamed({:?}:{:?}, {})",
906 did.krate, did.index, name)
908 BrEnv => write!(f, "BrEnv"),
915 () ty::PlaceholderRegion, (self, f, cx) {
918 return self.print_debug(f, cx);
921 let highlight = RegionHighlightMode::get();
922 if let Some(counter) = highlight.placeholder_highlight(*self) {
923 write!(f, "'{}", counter)
924 } else if highlight.any_placeholders_highlighted() {
927 write!(f, "{}", self.name)
934 () ty::RegionKind, (self, f, cx) {
937 return self.print_debug(f, cx);
940 // Watch out for region highlights.
941 if let Some(n) = RegionHighlightMode::get().region_highlighted(self) {
942 return write!(f, "'{:?}", n);
945 // These printouts are concise. They do not contain all the information
946 // the user might want to diagnose an error, but there is basically no way
947 // to fit that into a short string. Hence the recommendation to use
948 // `explain_region()` or `note_and_explain_region()`.
950 ty::ReEarlyBound(ref data) => {
951 write!(f, "{}", data.name)
953 ty::ReLateBound(_, br) |
954 ty::ReFree(ty::FreeRegion { bound_region: br, .. }) => {
957 ty::RePlaceholder(p) => {
960 ty::ReScope(scope) if cx.identify_regions => {
962 region::ScopeData::Node =>
963 write!(f, "'{}s", scope.item_local_id().as_usize()),
964 region::ScopeData::CallSite =>
965 write!(f, "'{}cs", scope.item_local_id().as_usize()),
966 region::ScopeData::Arguments =>
967 write!(f, "'{}as", scope.item_local_id().as_usize()),
968 region::ScopeData::Destruction =>
969 write!(f, "'{}ds", scope.item_local_id().as_usize()),
970 region::ScopeData::Remainder(first_statement_index) => write!(
973 scope.item_local_id().as_usize(),
974 first_statement_index.index()
978 ty::ReVar(region_vid) => {
979 if RegionHighlightMode::get().any_region_vids_highlighted() {
980 write!(f, "{:?}", region_vid)
981 } else if cx.identify_regions {
982 write!(f, "'{}rv", region_vid.index())
988 ty::ReErased => Ok(()),
989 ty::ReStatic => write!(f, "'static"),
990 ty::ReEmpty => write!(f, "'<empty>"),
992 // The user should never encounter these in unsubstituted form.
993 ty::ReClosureBound(vid) => write!(f, "{:?}", vid),
998 ty::ReEarlyBound(ref data) => {
999 write!(f, "ReEarlyBound({}, {})",
1004 ty::ReClosureBound(ref vid) => {
1005 write!(f, "ReClosureBound({:?})",
1009 ty::ReLateBound(binder_id, ref bound_region) => {
1010 write!(f, "ReLateBound({:?}, {:?})",
1015 ty::ReFree(ref fr) => write!(f, "{:?}", fr),
1017 ty::ReScope(id) => {
1018 write!(f, "ReScope({:?})", id)
1021 ty::ReStatic => write!(f, "ReStatic"),
1023 ty::ReVar(ref vid) => {
1024 write!(f, "{:?}", vid)
1027 ty::RePlaceholder(placeholder) => {
1028 write!(f, "RePlaceholder({:?})", placeholder)
1031 ty::ReEmpty => write!(f, "ReEmpty"),
1033 ty::ReErased => write!(f, "ReErased")
1040 () ty::FreeRegion, (self, f, cx) {
1042 write!(f, "ReFree({:?}, {:?})", self.scope, self.bound_region)
1048 () ty::Variance, (self, f, cx) {
1050 f.write_str(match *self {
1051 ty::Covariant => "+",
1052 ty::Contravariant => "-",
1053 ty::Invariant => "o",
1054 ty::Bivariant => "*",
1061 ('tcx) ty::GenericPredicates<'tcx>, (self, f, cx) {
1063 write!(f, "GenericPredicates({:?})", self.predicates)
1069 ('tcx) ty::InstantiatedPredicates<'tcx>, (self, f, cx) {
1071 write!(f, "InstantiatedPredicates({:?})", self.predicates)
1077 ('tcx) ty::FnSig<'tcx>, (self, f, cx) {
1079 if self.unsafety == hir::Unsafety::Unsafe {
1080 write!(f, "unsafe ")?;
1083 if self.abi != Abi::Rust {
1084 write!(f, "extern {} ", self.abi)?;
1088 cx.fn_sig(f, self.inputs(), self.c_variadic, self.output())
1091 write!(f, "({:?}; c_variadic: {})->{:?}", self.inputs(), self.c_variadic, self.output())
1096 impl fmt::Debug for ty::TyVid {
1097 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1098 write!(f, "_#{}t", self.index)
1102 impl<'tcx> fmt::Debug for ty::ConstVid<'tcx> {
1103 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1104 write!(f, "_#{}f", self.index)
1108 impl fmt::Debug for ty::IntVid {
1109 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1110 write!(f, "_#{}i", self.index)
1114 impl fmt::Debug for ty::FloatVid {
1115 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1116 write!(f, "_#{}f", self.index)
1120 impl fmt::Debug for ty::RegionVid {
1121 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1122 if let Some(counter) = RegionHighlightMode::get().region_highlighted(&ty::ReVar(*self)) {
1123 return write!(f, "'{:?}", counter);
1124 } else if RegionHighlightMode::get().any_region_vids_highlighted() {
1125 return write!(f, "'_");
1128 write!(f, "'_#{}r", self.index())
1133 () ty::InferTy, (self, f, cx) {
1136 print!(f, cx, print_debug(self))
1139 ty::TyVar(_) => write!(f, "_"),
1140 ty::IntVar(_) => write!(f, "{}", "{integer}"),
1141 ty::FloatVar(_) => write!(f, "{}", "{float}"),
1142 ty::FreshTy(v) => write!(f, "FreshTy({})", v),
1143 ty::FreshIntTy(v) => write!(f, "FreshIntTy({})", v),
1144 ty::FreshFloatTy(v) => write!(f, "FreshFloatTy({})", v)
1150 ty::TyVar(ref v) => write!(f, "{:?}", v),
1151 ty::IntVar(ref v) => write!(f, "{:?}", v),
1152 ty::FloatVar(ref v) => write!(f, "{:?}", v),
1153 ty::FreshTy(v) => write!(f, "FreshTy({:?})", v),
1154 ty::FreshIntTy(v) => write!(f, "FreshIntTy({:?})", v),
1155 ty::FreshFloatTy(v) => write!(f, "FreshFloatTy({:?})", v)
1161 impl fmt::Debug for ty::IntVarValue {
1162 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1164 ty::IntType(ref v) => v.fmt(f),
1165 ty::UintType(ref v) => v.fmt(f),
1170 impl fmt::Debug for ty::FloatVarValue {
1171 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1176 // The generic impl doesn't work yet because projections are not
1177 // normalized under HRTB.
1178 /*impl<T> fmt::Display for ty::Binder<T>
1179 where T: fmt::Display + for<'a> ty::Lift<'a>,
1180 for<'a> <T as ty::Lift<'a>>::Lifted: fmt::Display + TypeFoldable<'a>
1182 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1183 ty::tls::with(|tcx| in_binder(f, tcx, self, tcx.lift(self)))
1187 define_print_multi! {
1189 ('tcx) ty::Binder<&'tcx ty::List<ty::ExistentialPredicate<'tcx>>>,
1190 ('tcx) ty::Binder<ty::TraitRef<'tcx>>,
1191 ('tcx) ty::Binder<ty::FnSig<'tcx>>,
1192 ('tcx) ty::Binder<ty::TraitPredicate<'tcx>>,
1193 ('tcx) ty::Binder<ty::SubtypePredicate<'tcx>>,
1194 ('tcx) ty::Binder<ty::ProjectionPredicate<'tcx>>,
1195 ('tcx) ty::Binder<ty::OutlivesPredicate<Ty<'tcx>, ty::Region<'tcx>>>,
1196 ('tcx) ty::Binder<ty::OutlivesPredicate<ty::Region<'tcx>, ty::Region<'tcx>>>
1200 ty::tls::with(|tcx| cx.in_binder(f, tcx, self, tcx.lift(self)))
1206 ('tcx) ty::TraitRef<'tcx>, (self, f, cx) {
1208 cx.parameterized(f, self.substs, self.def_id, &[])
1211 // when printing out the debug representation, we don't need
1212 // to enumerate the `for<...>` etc because the debruijn index
1213 // tells you everything you need to know.
1216 print(self.self_ty()),
1218 cx.parameterized(f, self.substs, self.def_id, &[])?;
1225 ('tcx) ty::TyKind<'tcx>, (self, f, cx) {
1228 Bool => write!(f, "bool"),
1229 Char => write!(f, "char"),
1230 Int(t) => write!(f, "{}", t.ty_to_string()),
1231 Uint(t) => write!(f, "{}", t.ty_to_string()),
1232 Float(t) => write!(f, "{}", t.ty_to_string()),
1234 write!(f, "*{} ", match tm.mutbl {
1235 hir::MutMutable => "mut",
1236 hir::MutImmutable => "const",
1240 Ref(r, ty, mutbl) => {
1242 let s = r.print_to_string(cx);
1244 write!(f, "{}", s)?;
1249 ty::TypeAndMut { ty, mutbl }.print(f, cx)
1251 Never => write!(f, "!"),
1254 let mut tys = tys.iter();
1255 if let Some(&ty) = tys.next() {
1256 print!(f, cx, print(ty), write(","))?;
1257 if let Some(&ty) = tys.next() {
1258 print!(f, cx, write(" "), print(ty))?;
1260 print!(f, cx, write(", "), print(ty))?;
1266 FnDef(def_id, substs) => {
1267 ty::tls::with(|tcx| {
1268 let mut sig = tcx.fn_sig(def_id);
1269 if let Some(substs) = tcx.lift(&substs) {
1270 sig = sig.subst(tcx, substs);
1272 print!(f, cx, print(sig), write(" {{"))
1274 cx.parameterized(f, substs, def_id, &[])?;
1277 FnPtr(ref bare_fn) => {
1278 bare_fn.print(f, cx)
1280 Infer(infer_ty) => write!(f, "{}", infer_ty),
1281 Error => write!(f, "[type error]"),
1282 Param(ref param_ty) => write!(f, "{}", param_ty),
1283 Bound(debruijn, bound_ty) => {
1284 match bound_ty.kind {
1285 ty::BoundTyKind::Anon => {
1286 if debruijn == ty::INNERMOST {
1287 write!(f, "^{}", bound_ty.var.index())
1289 write!(f, "^{}_{}", debruijn.index(), bound_ty.var.index())
1293 ty::BoundTyKind::Param(p) => write!(f, "{}", p),
1296 Adt(def, substs) => cx.parameterized(f, substs, def.did, &[]),
1297 Dynamic(data, r) => {
1298 let r = r.print_to_string(cx);
1305 write!(f, " + {})", r)
1310 Foreign(def_id) => parameterized(f, subst::InternalSubsts::empty(), def_id, &[]),
1311 Projection(ref data) => data.print(f, cx),
1312 UnnormalizedProjection(ref data) => {
1313 write!(f, "Unnormalized(")?;
1317 Placeholder(placeholder) => {
1318 write!(f, "Placeholder({:?})", placeholder)
1320 Opaque(def_id, substs) => {
1322 return write!(f, "Opaque({:?}, {:?})", def_id, substs);
1325 ty::tls::with(|tcx| {
1326 let def_key = tcx.def_key(def_id);
1327 if let Some(name) = def_key.disambiguated_data.data.get_opt_name() {
1328 write!(f, "{}", name)?;
1329 let mut substs = substs.iter();
1330 if let Some(first) = substs.next() {
1332 write!(f, "{}", first)?;
1333 for subst in substs {
1334 write!(f, ", {}", subst)?;
1340 // Grab the "TraitA + TraitB" from `impl TraitA + TraitB`,
1341 // by looking up the projections associated with the def_id.
1342 let predicates_of = tcx.predicates_of(def_id);
1343 let substs = tcx.lift(&substs).unwrap_or_else(|| {
1344 tcx.intern_substs(&[])
1346 let bounds = predicates_of.instantiate(tcx, substs);
1348 let mut first = true;
1349 let mut is_sized = false;
1351 for predicate in bounds.predicates {
1352 if let Some(trait_ref) = predicate.to_opt_poly_trait_ref() {
1353 // Don't print +Sized, but rather +?Sized if absent.
1354 if Some(trait_ref.def_id()) == tcx.lang_items().sized_trait() {
1360 write("{}", if first { " " } else { "+" }),
1366 write!(f, "{}?Sized", if first { " " } else { "+" })?;
1368 write!(f, " Sized")?;
1373 Str => write!(f, "str"),
1374 Generator(did, substs, movability) => ty::tls::with(|tcx| {
1375 let upvar_tys = substs.upvar_tys(did, tcx);
1376 let witness = substs.witness(did, tcx);
1377 if movability == hir::GeneratorMovability::Movable {
1378 write!(f, "[generator")?;
1380 write!(f, "[static generator")?;
1383 if let Some(hir_id) = tcx.hir().as_local_hir_id(did) {
1384 write!(f, "@{:?}", tcx.hir().span_by_hir_id(hir_id))?;
1386 tcx.with_freevars(hir_id, |freevars| {
1387 for (freevar, upvar_ty) in freevars.iter().zip(upvar_tys) {
1391 tcx.hir().name(freevar.var_id())),
1398 // cross-crate closure types should only be
1399 // visible in codegen bug reports, I imagine.
1400 write!(f, "@{:?}", did)?;
1402 for (index, upvar_ty) in upvar_tys.enumerate() {
1404 write("{}{}:", sep, index),
1410 print!(f, cx, write(" "), print(witness), write("]"))
1412 GeneratorWitness(types) => {
1413 ty::tls::with(|tcx| cx.in_binder(f, tcx, &types, tcx.lift(&types)))
1415 Closure(did, substs) => ty::tls::with(|tcx| {
1416 let upvar_tys = substs.upvar_tys(did, tcx);
1417 write!(f, "[closure")?;
1419 if let Some(hir_id) = tcx.hir().as_local_hir_id(did) {
1420 if tcx.sess.opts.debugging_opts.span_free_formats {
1421 write!(f, "@{:?}", hir_id)?;
1423 write!(f, "@{:?}", tcx.hir().span_by_hir_id(hir_id))?;
1426 tcx.with_freevars(hir_id, |freevars| {
1427 for (freevar, upvar_ty) in freevars.iter().zip(upvar_tys) {
1431 tcx.hir().name(freevar.var_id())),
1438 // cross-crate closure types should only be
1439 // visible in codegen bug reports, I imagine.
1440 write!(f, "@{:?}", did)?;
1442 for (index, upvar_ty) in upvar_tys.enumerate() {
1444 write("{}{}:", sep, index),
1453 " closure_kind_ty={:?} closure_sig_ty={:?}",
1454 substs.closure_kind_ty(did, tcx),
1455 substs.closure_sig_ty(did, tcx),
1462 print!(f, cx, write("["), print(ty), write("; "))?;
1464 ty::LazyConst::Unevaluated(_def_id, _substs) => {
1467 ty::LazyConst::Evaluated(c) => ty::tls::with(|tcx| {
1469 ConstValue::Infer(..) => write!(f, "_"),
1470 ConstValue::Param(ParamConst { name, .. }) =>
1471 write!(f, "{}", name),
1472 _ => write!(f, "{}", c.unwrap_usize(tcx)),
1479 print!(f, cx, write("["), print(ty), write("]"))
1487 ('tcx) ty::TyS<'tcx>, (self, f, cx) {
1489 self.sty.print(f, cx)
1492 self.sty.print_display(f, cx)
1498 ('tcx) ConstValue<'tcx>, (self, f, cx) {
1501 ConstValue::Infer(..) => write!(f, "_"),
1502 ConstValue::Param(ParamConst { name, .. }) => write!(f, "{}", name),
1503 _ => write!(f, "{:?}", self),
1510 ('tcx) ty::Const<'tcx>, (self, f, cx) {
1512 write!(f, "{} : {}", self.val, self.ty)
1518 ('tcx) ty::LazyConst<'tcx>, (self, f, cx) {
1521 ty::LazyConst::Unevaluated(..) => write!(f, "_ : _"),
1522 ty::LazyConst::Evaluated(c) => write!(f, "{}", c),
1529 () ty::ParamTy, (self, f, cx) {
1531 write!(f, "{}", self.name)
1534 write!(f, "{}/#{}", self.name, self.idx)
1540 () ty::ParamConst, (self, f, cx) {
1542 write!(f, "{}", self.name)
1545 write!(f, "{}/#{}", self.name, self.index)
1551 ('tcx, T: Print + fmt::Debug, U: Print + fmt::Debug) ty::OutlivesPredicate<T, U>,
1554 print!(f, cx, print(self.0), write(" : "), print(self.1))
1560 ('tcx) ty::SubtypePredicate<'tcx>, (self, f, cx) {
1562 print!(f, cx, print(self.a), write(" <: "), print(self.b))
1568 ('tcx) ty::TraitPredicate<'tcx>, (self, f, cx) {
1570 write!(f, "TraitPredicate({:?})",
1574 print!(f, cx, print(self.trait_ref.self_ty()), write(": "), print(self.trait_ref))
1580 ('tcx) ty::ProjectionPredicate<'tcx>, (self, f, cx) {
1583 write("ProjectionPredicate("),
1584 print(self.projection_ty),
1590 print!(f, cx, print(self.projection_ty), write(" == "), print(self.ty))
1596 ('tcx) ty::ProjectionTy<'tcx>, (self, f, cx) {
1598 // FIXME(tschottdorf): use something like
1599 // parameterized(f, self.substs, self.item_def_id, &[])
1600 // (which currently ICEs).
1601 let (trait_ref, item_name) = ty::tls::with(|tcx|
1602 (self.trait_ref(tcx), tcx.associated_item(self.item_def_id).ident)
1604 print!(f, cx, print_debug(trait_ref), write("::{}", item_name))
1610 () ty::ClosureKind, (self, f, cx) {
1613 ty::ClosureKind::Fn => write!(f, "Fn"),
1614 ty::ClosureKind::FnMut => write!(f, "FnMut"),
1615 ty::ClosureKind::FnOnce => write!(f, "FnOnce"),
1622 ('tcx) ty::Predicate<'tcx>, (self, f, cx) {
1625 ty::Predicate::Trait(ref data) => data.print(f, cx),
1626 ty::Predicate::Subtype(ref predicate) => predicate.print(f, cx),
1627 ty::Predicate::RegionOutlives(ref predicate) => predicate.print(f, cx),
1628 ty::Predicate::TypeOutlives(ref predicate) => predicate.print(f, cx),
1629 ty::Predicate::Projection(ref predicate) => predicate.print(f, cx),
1630 ty::Predicate::WellFormed(ty) => print!(f, cx, print(ty), write(" well-formed")),
1631 ty::Predicate::ObjectSafe(trait_def_id) =>
1632 ty::tls::with(|tcx| {
1633 write!(f, "the trait `{}` is object-safe", tcx.item_path_str(trait_def_id))
1635 ty::Predicate::ClosureKind(closure_def_id, _closure_substs, kind) =>
1636 ty::tls::with(|tcx| {
1637 write!(f, "the closure `{}` implements the trait `{}`",
1638 tcx.item_path_str(closure_def_id), kind)
1640 ty::Predicate::ConstEvaluatable(def_id, substs) => {
1641 write!(f, "the constant `")?;
1642 cx.parameterized(f, substs, def_id, &[])?;
1643 write!(f, "` can be evaluated")
1649 ty::Predicate::Trait(ref a) => a.print(f, cx),
1650 ty::Predicate::Subtype(ref pair) => pair.print(f, cx),
1651 ty::Predicate::RegionOutlives(ref pair) => pair.print(f, cx),
1652 ty::Predicate::TypeOutlives(ref pair) => pair.print(f, cx),
1653 ty::Predicate::Projection(ref pair) => pair.print(f, cx),
1654 ty::Predicate::WellFormed(ty) => ty.print(f, cx),
1655 ty::Predicate::ObjectSafe(trait_def_id) => {
1656 write!(f, "ObjectSafe({:?})", trait_def_id)
1658 ty::Predicate::ClosureKind(closure_def_id, closure_substs, kind) => {
1659 write!(f, "ClosureKind({:?}, {:?}, {:?})", closure_def_id, closure_substs, kind)
1661 ty::Predicate::ConstEvaluatable(def_id, substs) => {
1662 write!(f, "ConstEvaluatable({:?}, {:?})", def_id, substs)