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android / toolchain / rustc / 89a0a0cd9cbd0a0138a09bd877bbc73859a8c330 / . / src / librustdoc / clean / mod.rs
blob: 64a18757b26e5f166770913e93b732b00c012460 [file] [log] [blame]
//! This module contains the "cleaned" pieces of the AST, and the functions
//! that clean them.
mod auto_trait;
mod blanket_impl;
pub(crate) mod cfg;
pub(crate) mod inline;
mod render_macro_matchers;
mod simplify;
pub(crate) mod types;
pub(crate) mod utils;
use rustc_ast as ast;
use rustc_attr as attr;
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
use rustc_hir as hir;
use rustc_hir::def::{CtorKind, DefKind, Res};
use rustc_hir::def_id::{DefId, LOCAL_CRATE};
use rustc_hir::PredicateOrigin;
use rustc_hir_analysis::hir_ty_to_ty;
use rustc_infer::infer::region_constraints::{Constraint, RegionConstraintData};
use rustc_middle::middle::resolve_lifetime as rl;
use rustc_middle::ty::fold::TypeFolder;
use rustc_middle::ty::InternalSubsts;
use rustc_middle::ty::{self, AdtKind, DefIdTree, EarlyBinder, Ty, TyCtxt};
use rustc_middle::{bug, span_bug};
use rustc_span::hygiene::{AstPass, MacroKind};
use rustc_span::symbol::{kw, sym, Ident, Symbol};
use rustc_span::{self, ExpnKind};
use std::assert_matches::assert_matches;
use std::collections::hash_map::Entry;
use std::collections::BTreeMap;
use std::default::Default;
use std::hash::Hash;
use std::mem;
use thin_vec::ThinVec;
use crate::core::{self, DocContext, ImplTraitParam};
use crate::formats::item_type::ItemType;
use crate::visit_ast::Module as DocModule;
use utils::*;
pub(crate) use self::types::*;
pub(crate) use self::utils::{get_auto_trait_and_blanket_impls, krate, register_res};
pub(crate) fn clean_doc_module<'tcx>(doc: &DocModule<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
let mut items: Vec<Item> = vec![];
let mut inserted = FxHashSet::default();
items.extend(doc.foreigns.iter().map(|(item, renamed)| {
let item = clean_maybe_renamed_foreign_item(cx, item, *renamed);
if let Some(name) = item.name && !item.attrs.lists(sym::doc).has_word(sym::hidden) {
inserted.insert((item.type_(), name));
}
item
}));
items.extend(doc.mods.iter().filter_map(|x| {
if !inserted.insert((ItemType::Module, x.name)) {
return None;
}
let item = clean_doc_module(x, cx);
if item.attrs.lists(sym::doc).has_word(sym::hidden) {
// Hidden modules are stripped at a later stage.
// If a hidden module has the same name as a visible one, we want
// to keep both of them around.
inserted.remove(&(ItemType::Module, x.name));
}
Some(item)
}));
// Split up imports from all other items.
//
// This covers the case where somebody does an import which should pull in an item,
// but there's already an item with the same namespace and same name. Rust gives
// priority to the not-imported one, so we should, too.
items.extend(doc.items.iter().flat_map(|(item, renamed)| {
// First, lower everything other than imports.
if matches!(item.kind, hir::ItemKind::Use(_, hir::UseKind::Glob)) {
return Vec::new();
}
let v = clean_maybe_renamed_item(cx, item, *renamed);
for item in &v {
if let Some(name) = item.name && !item.attrs.lists(sym::doc).has_word(sym::hidden) {
inserted.insert((item.type_(), name));
}
}
v
}));
items.extend(doc.items.iter().flat_map(|(item, renamed)| {
// Now we actually lower the imports, skipping everything else.
if let hir::ItemKind::Use(path, hir::UseKind::Glob) = item.kind {
let name = renamed.unwrap_or_else(|| cx.tcx.hir().name(item.hir_id()));
clean_use_statement(item, name, path, hir::UseKind::Glob, cx, &mut inserted)
} else {
// skip everything else
Vec::new()
}
}));
// determine if we should display the inner contents or
// the outer `mod` item for the source code.
let span = Span::new({
let where_outer = doc.where_outer(cx.tcx);
let sm = cx.sess().source_map();
let outer = sm.lookup_char_pos(where_outer.lo());
let inner = sm.lookup_char_pos(doc.where_inner.lo());
if outer.file.start_pos == inner.file.start_pos {
// mod foo { ... }
where_outer
} else {
// mod foo; (and a separate SourceFile for the contents)
doc.where_inner
}
});
Item::from_hir_id_and_parts(doc.id, Some(doc.name), ModuleItem(Module { items, span }), cx)
}
fn clean_generic_bound<'tcx>(
bound: &hir::GenericBound<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Option<GenericBound> {
Some(match *bound {
hir::GenericBound::Outlives(lt) => GenericBound::Outlives(clean_lifetime(lt, cx)),
hir::GenericBound::LangItemTrait(lang_item, span, _, generic_args) => {
let def_id = cx.tcx.require_lang_item(lang_item, Some(span));
let trait_ref = ty::TraitRef::identity(cx.tcx, def_id).skip_binder();
let generic_args = clean_generic_args(generic_args, cx);
let GenericArgs::AngleBracketed { bindings, .. } = generic_args
else {
bug!("clean: parenthesized `GenericBound::LangItemTrait`");
};
let trait_ = clean_trait_ref_with_bindings(cx, trait_ref, bindings);
GenericBound::TraitBound(
PolyTrait { trait_, generic_params: vec![] },
hir::TraitBoundModifier::None,
)
}
hir::GenericBound::Trait(ref t, modifier) => {
// `T: ~const Destruct` is hidden because `T: Destruct` is a no-op.
if modifier == hir::TraitBoundModifier::MaybeConst
&& cx.tcx.lang_items().destruct_trait() == Some(t.trait_ref.trait_def_id().unwrap())
{
return None;
}
GenericBound::TraitBound(clean_poly_trait_ref(t, cx), modifier)
}
})
}
pub(crate) fn clean_trait_ref_with_bindings<'tcx>(
cx: &mut DocContext<'tcx>,
trait_ref: ty::TraitRef<'tcx>,
bindings: ThinVec<TypeBinding>,
) -> Path {
let kind = cx.tcx.def_kind(trait_ref.def_id).into();
if !matches!(kind, ItemType::Trait | ItemType::TraitAlias) {
span_bug!(cx.tcx.def_span(trait_ref.def_id), "`TraitRef` had unexpected kind {:?}", kind);
}
inline::record_extern_fqn(cx, trait_ref.def_id, kind);
let path = external_path(cx, trait_ref.def_id, true, bindings, trait_ref.substs);
debug!("ty::TraitRef\n subst: {:?}\n", trait_ref.substs);
path
}
fn clean_poly_trait_ref_with_bindings<'tcx>(
cx: &mut DocContext<'tcx>,
poly_trait_ref: ty::PolyTraitRef<'tcx>,
bindings: ThinVec<TypeBinding>,
) -> GenericBound {
// collect any late bound regions
let late_bound_regions: Vec<_> = cx
.tcx
.collect_referenced_late_bound_regions(&poly_trait_ref)
.into_iter()
.filter_map(|br| match br {
ty::BrNamed(_, name) if name != kw::UnderscoreLifetime => Some(GenericParamDef {
name,
kind: GenericParamDefKind::Lifetime { outlives: vec![] },
}),
_ => None,
})
.collect();
let trait_ = clean_trait_ref_with_bindings(cx, poly_trait_ref.skip_binder(), bindings);
GenericBound::TraitBound(
PolyTrait { trait_, generic_params: late_bound_regions },
hir::TraitBoundModifier::None,
)
}
fn clean_lifetime<'tcx>(lifetime: &hir::Lifetime, cx: &mut DocContext<'tcx>) -> Lifetime {
let def = cx.tcx.named_region(lifetime.hir_id);
if let Some(
rl::Region::EarlyBound(node_id)
| rl::Region::LateBound(_, _, node_id)
| rl::Region::Free(_, node_id),
) = def
{
if let Some(lt) = cx.substs.get(&node_id).and_then(|p| p.as_lt()).cloned() {
return lt;
}
}
Lifetime(lifetime.name.ident().name)
}
pub(crate) fn clean_const<'tcx>(constant: &hir::ConstArg, cx: &mut DocContext<'tcx>) -> Constant {
let def_id = cx.tcx.hir().body_owner_def_id(constant.value.body).to_def_id();
Constant {
type_: clean_middle_ty(cx.tcx.type_of(def_id), cx, Some(def_id)),
kind: ConstantKind::Anonymous { body: constant.value.body },
}
}
pub(crate) fn clean_middle_const<'tcx>(
constant: ty::Const<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Constant {
// FIXME: instead of storing the stringified expression, store `self` directly instead.
Constant {
type_: clean_middle_ty(constant.ty(), cx, None),
kind: ConstantKind::TyConst { expr: constant.to_string() },
}
}
pub(crate) fn clean_middle_region<'tcx>(region: ty::Region<'tcx>) -> Option<Lifetime> {
match *region {
ty::ReStatic => Some(Lifetime::statik()),
ty::ReLateBound(_, ty::BoundRegion { kind: ty::BrNamed(_, name), .. }) => {
if name != kw::UnderscoreLifetime { Some(Lifetime(name)) } else { None }
}
ty::ReEarlyBound(ref data) => {
if data.name != kw::UnderscoreLifetime {
Some(Lifetime(data.name))
} else {
None
}
}
ty::ReLateBound(..)
| ty::ReFree(..)
| ty::ReVar(..)
| ty::RePlaceholder(..)
| ty::ReErased => {
debug!("cannot clean region {:?}", region);
None
}
}
}
fn clean_where_predicate<'tcx>(
predicate: &hir::WherePredicate<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Option<WherePredicate> {
if !predicate.in_where_clause() {
return None;
}
Some(match *predicate {
hir::WherePredicate::BoundPredicate(ref wbp) => {
let bound_params = wbp
.bound_generic_params
.iter()
.map(|param| {
// Higher-ranked params must be lifetimes.
// Higher-ranked lifetimes can't have bounds.
assert_matches!(
param,
hir::GenericParam { kind: hir::GenericParamKind::Lifetime { .. }, .. }
);
Lifetime(param.name.ident().name)
})
.collect();
WherePredicate::BoundPredicate {
ty: clean_ty(wbp.bounded_ty, cx),
bounds: wbp.bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect(),
bound_params,
}
}
hir::WherePredicate::RegionPredicate(ref wrp) => WherePredicate::RegionPredicate {
lifetime: clean_lifetime(wrp.lifetime, cx),
bounds: wrp.bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect(),
},
hir::WherePredicate::EqPredicate(ref wrp) => WherePredicate::EqPredicate {
lhs: Box::new(clean_ty(wrp.lhs_ty, cx)),
rhs: Box::new(clean_ty(wrp.rhs_ty, cx).into()),
bound_params: Vec::new(),
},
})
}
pub(crate) fn clean_predicate<'tcx>(
predicate: ty::Predicate<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Option<WherePredicate> {
let bound_predicate = predicate.kind();
match bound_predicate.skip_binder() {
ty::PredicateKind::Trait(pred) => {
clean_poly_trait_predicate(bound_predicate.rebind(pred), cx)
}
ty::PredicateKind::RegionOutlives(pred) => clean_region_outlives_predicate(pred),
ty::PredicateKind::TypeOutlives(pred) => clean_type_outlives_predicate(pred, cx),
ty::PredicateKind::Projection(pred) => {
Some(clean_projection_predicate(bound_predicate.rebind(pred), cx))
}
ty::PredicateKind::ConstEvaluatable(..) => None,
ty::PredicateKind::WellFormed(..) => None,
ty::PredicateKind::Subtype(..)
| ty::PredicateKind::Coerce(..)
| ty::PredicateKind::ObjectSafe(..)
| ty::PredicateKind::ClosureKind(..)
| ty::PredicateKind::ConstEquate(..)
| ty::PredicateKind::TypeWellFormedFromEnv(..) => panic!("not user writable"),
}
}
fn clean_poly_trait_predicate<'tcx>(
pred: ty::PolyTraitPredicate<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Option<WherePredicate> {
// `T: ~const Destruct` is hidden because `T: Destruct` is a no-op.
if pred.skip_binder().constness == ty::BoundConstness::ConstIfConst
&& Some(pred.skip_binder().def_id()) == cx.tcx.lang_items().destruct_trait()
{
return None;
}
let poly_trait_ref = pred.map_bound(|pred| pred.trait_ref);
Some(WherePredicate::BoundPredicate {
ty: clean_middle_ty(poly_trait_ref.skip_binder().self_ty(), cx, None),
bounds: vec![clean_poly_trait_ref_with_bindings(cx, poly_trait_ref, ThinVec::new())],
bound_params: Vec::new(),
})
}
fn clean_region_outlives_predicate<'tcx>(
pred: ty::OutlivesPredicate<ty::Region<'tcx>, ty::Region<'tcx>>,
) -> Option<WherePredicate> {
let ty::OutlivesPredicate(a, b) = pred;
Some(WherePredicate::RegionPredicate {
lifetime: clean_middle_region(a).expect("failed to clean lifetime"),
bounds: vec![GenericBound::Outlives(
clean_middle_region(b).expect("failed to clean bounds"),
)],
})
}
fn clean_type_outlives_predicate<'tcx>(
pred: ty::OutlivesPredicate<Ty<'tcx>, ty::Region<'tcx>>,
cx: &mut DocContext<'tcx>,
) -> Option<WherePredicate> {
let ty::OutlivesPredicate(ty, lt) = pred;
Some(WherePredicate::BoundPredicate {
ty: clean_middle_ty(ty, cx, None),
bounds: vec![GenericBound::Outlives(
clean_middle_region(lt).expect("failed to clean lifetimes"),
)],
bound_params: Vec::new(),
})
}
fn clean_middle_term<'tcx>(term: ty::Term<'tcx>, cx: &mut DocContext<'tcx>) -> Term {
match term.unpack() {
ty::TermKind::Ty(ty) => Term::Type(clean_middle_ty(ty, cx, None)),
ty::TermKind::Const(c) => Term::Constant(clean_middle_const(c, cx)),
}
}
fn clean_hir_term<'tcx>(term: &hir::Term<'tcx>, cx: &mut DocContext<'tcx>) -> Term {
match term {
hir::Term::Ty(ty) => Term::Type(clean_ty(ty, cx)),
hir::Term::Const(c) => {
let def_id = cx.tcx.hir().local_def_id(c.hir_id);
Term::Constant(clean_middle_const(ty::Const::from_anon_const(cx.tcx, def_id), cx))
}
}
}
fn clean_projection_predicate<'tcx>(
pred: ty::Binder<'tcx, ty::ProjectionPredicate<'tcx>>,
cx: &mut DocContext<'tcx>,
) -> WherePredicate {
let late_bound_regions = cx
.tcx
.collect_referenced_late_bound_regions(&pred)
.into_iter()
.filter_map(|br| match br {
ty::BrNamed(_, name) if name != kw::UnderscoreLifetime => Some(Lifetime(name)),
_ => None,
})
.collect();
let ty::ProjectionPredicate { projection_ty, term } = pred.skip_binder();
WherePredicate::EqPredicate {
lhs: Box::new(clean_projection(projection_ty, cx, None)),
rhs: Box::new(clean_middle_term(term, cx)),
bound_params: late_bound_regions,
}
}
fn clean_projection<'tcx>(
ty: ty::ProjectionTy<'tcx>,
cx: &mut DocContext<'tcx>,
def_id: Option<DefId>,
) -> Type {
if cx.tcx.def_kind(ty.item_def_id) == DefKind::ImplTraitPlaceholder {
let bounds = cx
.tcx
.explicit_item_bounds(ty.item_def_id)
.iter()
.map(|(bound, _)| EarlyBinder(*bound).subst(cx.tcx, ty.substs))
.collect::<Vec<_>>();
return clean_middle_opaque_bounds(cx, bounds);
}
let trait_ = clean_trait_ref_with_bindings(cx, ty.trait_ref(cx.tcx), ThinVec::new());
let self_type = clean_middle_ty(ty.self_ty(), cx, None);
let self_def_id = if let Some(def_id) = def_id {
cx.tcx.opt_parent(def_id).or(Some(def_id))
} else {
self_type.def_id(&cx.cache)
};
let should_show_cast = compute_should_show_cast(self_def_id, &trait_, &self_type);
Type::QPath(Box::new(QPathData {
assoc: projection_to_path_segment(ty, cx),
should_show_cast,
self_type,
trait_,
}))
}
fn compute_should_show_cast(self_def_id: Option<DefId>, trait_: &Path, self_type: &Type) -> bool {
!trait_.segments.is_empty()
&& self_def_id
.zip(Some(trait_.def_id()))
.map_or(!self_type.is_self_type(), |(id, trait_)| id != trait_)
}
fn projection_to_path_segment<'tcx>(
ty: ty::ProjectionTy<'tcx>,
cx: &mut DocContext<'tcx>,
) -> PathSegment {
let item = cx.tcx.associated_item(ty.item_def_id);
let generics = cx.tcx.generics_of(ty.item_def_id);
PathSegment {
name: item.name,
args: GenericArgs::AngleBracketed {
args: substs_to_args(cx, &ty.substs[generics.parent_count..], false).into(),
bindings: Default::default(),
},
}
}
fn clean_generic_param_def<'tcx>(
def: &ty::GenericParamDef,
cx: &mut DocContext<'tcx>,
) -> GenericParamDef {
let (name, kind) = match def.kind {
ty::GenericParamDefKind::Lifetime => {
(def.name, GenericParamDefKind::Lifetime { outlives: vec![] })
}
ty::GenericParamDefKind::Type { has_default, synthetic, .. } => {
let default = if has_default {
Some(clean_middle_ty(cx.tcx.type_of(def.def_id), cx, Some(def.def_id)))
} else {
None
};
(
def.name,
GenericParamDefKind::Type {
did: def.def_id,
bounds: vec![], // These are filled in from the where-clauses.
default: default.map(Box::new),
synthetic,
},
)
}
ty::GenericParamDefKind::Const { has_default } => (
def.name,
GenericParamDefKind::Const {
did: def.def_id,
ty: Box::new(clean_middle_ty(cx.tcx.type_of(def.def_id), cx, Some(def.def_id))),
default: match has_default {
true => Some(Box::new(cx.tcx.const_param_default(def.def_id).to_string())),
false => None,
},
},
),
};
GenericParamDef { name, kind }
}
fn clean_generic_param<'tcx>(
cx: &mut DocContext<'tcx>,
generics: Option<&hir::Generics<'tcx>>,
param: &hir::GenericParam<'tcx>,
) -> GenericParamDef {
let did = cx.tcx.hir().local_def_id(param.hir_id);
let (name, kind) = match param.kind {
hir::GenericParamKind::Lifetime { .. } => {
let outlives = if let Some(generics) = generics {
generics
.outlives_for_param(did)
.filter(|bp| !bp.in_where_clause)
.flat_map(|bp| bp.bounds)
.map(|bound| match bound {
hir::GenericBound::Outlives(lt) => clean_lifetime(lt, cx),
_ => panic!(),
})
.collect()
} else {
Vec::new()
};
(param.name.ident().name, GenericParamDefKind::Lifetime { outlives })
}
hir::GenericParamKind::Type { ref default, synthetic } => {
let bounds = if let Some(generics) = generics {
generics
.bounds_for_param(did)
.filter(|bp| bp.origin != PredicateOrigin::WhereClause)
.flat_map(|bp| bp.bounds)
.filter_map(|x| clean_generic_bound(x, cx))
.collect()
} else {
Vec::new()
};
(
param.name.ident().name,
GenericParamDefKind::Type {
did: did.to_def_id(),
bounds,
default: default.map(|t| clean_ty(t, cx)).map(Box::new),
synthetic,
},
)
}
hir::GenericParamKind::Const { ty, default } => (
param.name.ident().name,
GenericParamDefKind::Const {
did: did.to_def_id(),
ty: Box::new(clean_ty(ty, cx)),
default: default.map(|ct| {
let def_id = cx.tcx.hir().local_def_id(ct.hir_id);
Box::new(ty::Const::from_anon_const(cx.tcx, def_id).to_string())
}),
},
),
};
GenericParamDef { name, kind }
}
/// Synthetic type-parameters are inserted after normal ones.
/// In order for normal parameters to be able to refer to synthetic ones,
/// scans them first.
fn is_impl_trait(param: &hir::GenericParam<'_>) -> bool {
match param.kind {
hir::GenericParamKind::Type { synthetic, .. } => synthetic,
_ => false,
}
}
/// This can happen for `async fn`, e.g. `async fn f<'_>(&'_ self)`.
///
/// See `lifetime_to_generic_param` in `rustc_ast_lowering` for more information.
fn is_elided_lifetime(param: &hir::GenericParam<'_>) -> bool {
matches!(param.kind, hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::Elided })
}
pub(crate) fn clean_generics<'tcx>(
gens: &hir::Generics<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Generics {
let impl_trait_params = gens
.params
.iter()
.filter(|param| is_impl_trait(param))
.map(|param| {
let param = clean_generic_param(cx, Some(gens), param);
match param.kind {
GenericParamDefKind::Lifetime { .. } => unreachable!(),
GenericParamDefKind::Type { did, ref bounds, .. } => {
cx.impl_trait_bounds.insert(did.into(), bounds.clone());
}
GenericParamDefKind::Const { .. } => unreachable!(),
}
param
})
.collect::<Vec<_>>();
let mut params = Vec::with_capacity(gens.params.len());
for p in gens.params.iter().filter(|p| !is_impl_trait(p) && !is_elided_lifetime(p)) {
let p = clean_generic_param(cx, Some(gens), p);
params.push(p);
}
params.extend(impl_trait_params);
let mut generics = Generics {
params,
where_predicates: gens
.predicates
.iter()
.filter_map(|x| clean_where_predicate(x, cx))
.collect(),
};
// Some duplicates are generated for ?Sized bounds between type params and where
// predicates. The point in here is to move the bounds definitions from type params
// to where predicates when such cases occur.
for where_pred in &mut generics.where_predicates {
match *where_pred {
WherePredicate::BoundPredicate { ty: Generic(ref name), ref mut bounds, .. } => {
if bounds.is_empty() {
for param in &mut generics.params {
match param.kind {
GenericParamDefKind::Lifetime { .. } => {}
GenericParamDefKind::Type { bounds: ref mut ty_bounds, .. } => {
if &param.name == name {
mem::swap(bounds, ty_bounds);
break;
}
}
GenericParamDefKind::Const { .. } => {}
}
}
}
}
_ => continue,
}
}
generics
}
fn clean_ty_generics<'tcx>(
cx: &mut DocContext<'tcx>,
gens: &ty::Generics,
preds: ty::GenericPredicates<'tcx>,
) -> Generics {
// Don't populate `cx.impl_trait_bounds` before `clean`ning `where` clauses,
// since `Clean for ty::Predicate` would consume them.
let mut impl_trait = BTreeMap::<ImplTraitParam, Vec<GenericBound>>::default();
// Bounds in the type_params and lifetimes fields are repeated in the
// predicates field (see rustc_hir_analysis::collect::ty_generics), so remove
// them.
let stripped_params = gens
.params
.iter()
.filter_map(|param| match param.kind {
ty::GenericParamDefKind::Lifetime if param.name == kw::UnderscoreLifetime => None,
ty::GenericParamDefKind::Lifetime => Some(clean_generic_param_def(param, cx)),
ty::GenericParamDefKind::Type { synthetic, .. } => {
if param.name == kw::SelfUpper {
assert_eq!(param.index, 0);
return None;
}
if synthetic {
impl_trait.insert(param.index.into(), vec![]);
return None;
}
Some(clean_generic_param_def(param, cx))
}
ty::GenericParamDefKind::Const { .. } => Some(clean_generic_param_def(param, cx)),
})
.collect::<Vec<GenericParamDef>>();
// param index -> [(trait DefId, associated type name & generics, type, higher-ranked params)]
let mut impl_trait_proj =
FxHashMap::<u32, Vec<(DefId, PathSegment, Ty<'_>, Vec<GenericParamDef>)>>::default();
let where_predicates = preds
.predicates
.iter()
.flat_map(|(p, _)| {
let mut projection = None;
let param_idx = (|| {
let bound_p = p.kind();
match bound_p.skip_binder() {
ty::PredicateKind::Trait(pred) => {
if let ty::Param(param) = pred.self_ty().kind() {
return Some(param.index);
}
}
ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(ty, _reg)) => {
if let ty::Param(param) = ty.kind() {
return Some(param.index);
}
}
ty::PredicateKind::Projection(p) => {
if let ty::Param(param) = p.projection_ty.self_ty().kind() {
projection = Some(bound_p.rebind(p));
return Some(param.index);
}
}
_ => (),
}
None
})();
if let Some(param_idx) = param_idx {
if let Some(b) = impl_trait.get_mut(&param_idx.into()) {
let p: WherePredicate = clean_predicate(*p, cx)?;
b.extend(
p.get_bounds()
.into_iter()
.flatten()
.cloned()
.filter(|b| !b.is_sized_bound(cx)),
);
let proj = projection.map(|p| {
(
clean_projection(p.skip_binder().projection_ty, cx, None),
p.skip_binder().term,
)
});
if let Some(((_, trait_did, name), rhs)) = proj
.as_ref()
.and_then(|(lhs, rhs): &(Type, _)| Some((lhs.projection()?, rhs)))
{
// FIXME(...): Remove this unwrap()
impl_trait_proj.entry(param_idx).or_default().push((
trait_did,
name,
rhs.ty().unwrap(),
p.get_bound_params()
.into_iter()
.flatten()
.map(|param| GenericParamDef {
name: param.0,
kind: GenericParamDefKind::Lifetime { outlives: Vec::new() },
})
.collect(),
));
}
return None;
}
}
Some(p)
})
.collect::<Vec<_>>();
for (param, mut bounds) in impl_trait {
// Move trait bounds to the front.
bounds.sort_by_key(|b| !matches!(b, GenericBound::TraitBound(..)));
let crate::core::ImplTraitParam::ParamIndex(idx) = param else { unreachable!() };
if let Some(proj) = impl_trait_proj.remove(&idx) {
for (trait_did, name, rhs, bound_params) in proj {
let rhs = clean_middle_ty(rhs, cx, None);
simplify::merge_bounds(
cx,
&mut bounds,
bound_params,
trait_did,
name,
&Term::Type(rhs),
);
}
}
cx.impl_trait_bounds.insert(param, bounds);
}
// Now that `cx.impl_trait_bounds` is populated, we can process
// remaining predicates which could contain `impl Trait`.
let mut where_predicates =
where_predicates.into_iter().flat_map(|p| clean_predicate(*p, cx)).collect::<Vec<_>>();
// In the surface language, all type parameters except `Self` have an
// implicit `Sized` bound unless removed with `?Sized`.
// However, in the list of where-predicates below, `Sized` appears like a
// normal bound: It's either present (the type is sized) or
// absent (the type is unsized) but never *maybe* (i.e. `?Sized`).
//
// This is unsuitable for rendering.
// Thus, as a first step remove all `Sized` bounds that should be implicit.
//
// Note that associated types also have an implicit `Sized` bound but we
// don't actually know the set of associated types right here so that's
// handled when cleaning associated types.
let mut sized_params = FxHashSet::default();
where_predicates.retain(|pred| {
if let WherePredicate::BoundPredicate { ty: Generic(g), bounds, .. } = pred
&& *g != kw::SelfUpper
&& bounds.iter().any(|b| b.is_sized_bound(cx))
{
sized_params.insert(*g);
false
} else {
true
}
});
// As a final step, go through the type parameters again and insert a
// `?Sized` bound for each one we didn't find to be `Sized`.
for tp in &stripped_params {
if let types::GenericParamDefKind::Type { .. } = tp.kind
&& !sized_params.contains(&tp.name)
{
where_predicates.push(WherePredicate::BoundPredicate {
ty: Type::Generic(tp.name),
bounds: vec![GenericBound::maybe_sized(cx)],
bound_params: Vec::new(),
})
}
}
// It would be nice to collect all of the bounds on a type and recombine
// them if possible, to avoid e.g., `where T: Foo, T: Bar, T: Sized, T: 'a`
// and instead see `where T: Foo + Bar + Sized + 'a`
Generics {
params: stripped_params,
where_predicates: simplify::where_clauses(cx, where_predicates),
}
}
fn clean_fn_or_proc_macro<'tcx>(
item: &hir::Item<'tcx>,
sig: &hir::FnSig<'tcx>,
generics: &hir::Generics<'tcx>,
body_id: hir::BodyId,
name: &mut Symbol,
cx: &mut DocContext<'tcx>,
) -> ItemKind {
let attrs = cx.tcx.hir().attrs(item.hir_id());
let macro_kind = attrs.iter().find_map(|a| {
if a.has_name(sym::proc_macro) {
Some(MacroKind::Bang)
} else if a.has_name(sym::proc_macro_derive) {
Some(MacroKind::Derive)
} else if a.has_name(sym::proc_macro_attribute) {
Some(MacroKind::Attr)
} else {
None
}
});
match macro_kind {
Some(kind) => {
if kind == MacroKind::Derive {
*name = attrs
.lists(sym::proc_macro_derive)
.find_map(|mi| mi.ident())
.expect("proc-macro derives require a name")
.name;
}
let mut helpers = Vec::new();
for mi in attrs.lists(sym::proc_macro_derive) {
if !mi.has_name(sym::attributes) {
continue;
}
if let Some(list) = mi.meta_item_list() {
for inner_mi in list {
if let Some(ident) = inner_mi.ident() {
helpers.push(ident.name);
}
}
}
}
ProcMacroItem(ProcMacro { kind, helpers })
}
None => {
let mut func = clean_function(cx, sig, generics, body_id);
clean_fn_decl_legacy_const_generics(&mut func, attrs);
FunctionItem(func)
}
}
}
/// This is needed to make it more "readable" when documenting functions using
/// `rustc_legacy_const_generics`. More information in
/// <https://github.com/rust-lang/rust/issues/83167>.
fn clean_fn_decl_legacy_const_generics(func: &mut Function, attrs: &[ast::Attribute]) {
for meta_item_list in attrs
.iter()
.filter(|a| a.has_name(sym::rustc_legacy_const_generics))
.filter_map(|a| a.meta_item_list())
{
for (pos, literal) in meta_item_list.iter().filter_map(|meta| meta.literal()).enumerate() {
match literal.kind {
ast::LitKind::Int(a, _) => {
let gen = func.generics.params.remove(0);
if let GenericParamDef { name, kind: GenericParamDefKind::Const { ty, .. } } =
gen
{
func.decl
.inputs
.values
.insert(a as _, Argument { name, type_: *ty, is_const: true });
} else {
panic!("unexpected non const in position {pos}");
}
}
_ => panic!("invalid arg index"),
}
}
}
}
fn clean_function<'tcx>(
cx: &mut DocContext<'tcx>,
sig: &hir::FnSig<'tcx>,
generics: &hir::Generics<'tcx>,
body_id: hir::BodyId,
) -> Box<Function> {
let (generics, decl) = enter_impl_trait(cx, |cx| {
// NOTE: generics must be cleaned before args
let generics = clean_generics(generics, cx);
let args = clean_args_from_types_and_body_id(cx, sig.decl.inputs, body_id);
let mut decl = clean_fn_decl_with_args(cx, sig.decl, args);
if sig.header.is_async() {
decl.output = decl.sugared_async_return_type();
}
(generics, decl)
});
Box::new(Function { decl, generics })
}
fn clean_args_from_types_and_names<'tcx>(
cx: &mut DocContext<'tcx>,
types: &[hir::Ty<'tcx>],
names: &[Ident],
) -> Arguments {
Arguments {
values: types
.iter()
.enumerate()
.map(|(i, ty)| {
let mut name = names.get(i).map_or(kw::Empty, |ident| ident.name);
if name.is_empty() {
name = kw::Underscore;
}
Argument { name, type_: clean_ty(ty, cx), is_const: false }
})
.collect(),
}
}
fn clean_args_from_types_and_body_id<'tcx>(
cx: &mut DocContext<'tcx>,
types: &[hir::Ty<'tcx>],
body_id: hir::BodyId,
) -> Arguments {
let body = cx.tcx.hir().body(body_id);
Arguments {
values: types
.iter()
.enumerate()
.map(|(i, ty)| Argument {
name: name_from_pat(body.params[i].pat),
type_: clean_ty(ty, cx),
is_const: false,
})
.collect(),
}
}
fn clean_fn_decl_with_args<'tcx>(
cx: &mut DocContext<'tcx>,
decl: &hir::FnDecl<'tcx>,
args: Arguments,
) -> FnDecl {
let output = match decl.output {
hir::FnRetTy::Return(typ) => Return(clean_ty(typ, cx)),
hir::FnRetTy::DefaultReturn(..) => DefaultReturn,
};
FnDecl { inputs: args, output, c_variadic: decl.c_variadic }
}
fn clean_fn_decl_from_did_and_sig<'tcx>(
cx: &mut DocContext<'tcx>,
did: Option<DefId>,
sig: ty::PolyFnSig<'tcx>,
) -> FnDecl {
let mut names = did.map_or(&[] as &[_], |did| cx.tcx.fn_arg_names(did)).iter();
// We assume all empty tuples are default return type. This theoretically can discard `-> ()`,
// but shouldn't change any code meaning.
let output = match clean_middle_ty(sig.skip_binder().output(), cx, None) {
Type::Tuple(inner) if inner.is_empty() => DefaultReturn,
ty => Return(ty),
};
FnDecl {
output,
c_variadic: sig.skip_binder().c_variadic,
inputs: Arguments {
values: sig
.skip_binder()
.inputs()
.iter()
.map(|t| Argument {
type_: clean_middle_ty(*t, cx, None),
name: names.next().map_or(kw::Empty, |i| i.name),
is_const: false,
})
.collect(),
},
}
}
fn clean_trait_ref<'tcx>(trait_ref: &hir::TraitRef<'tcx>, cx: &mut DocContext<'tcx>) -> Path {
let path = clean_path(trait_ref.path, cx);
register_res(cx, path.res);
path
}
fn clean_poly_trait_ref<'tcx>(
poly_trait_ref: &hir::PolyTraitRef<'tcx>,
cx: &mut DocContext<'tcx>,
) -> PolyTrait {
PolyTrait {
trait_: clean_trait_ref(&poly_trait_ref.trait_ref, cx),
generic_params: poly_trait_ref
.bound_generic_params
.iter()
.filter(|p| !is_elided_lifetime(p))
.map(|x| clean_generic_param(cx, None, x))
.collect(),
}
}
fn clean_trait_item<'tcx>(trait_item: &hir::TraitItem<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
let local_did = trait_item.owner_id.to_def_id();
cx.with_param_env(local_did, |cx| {
let inner = match trait_item.kind {
hir::TraitItemKind::Const(ty, Some(default)) => AssocConstItem(
clean_ty(ty, cx),
ConstantKind::Local { def_id: local_did, body: default },
),
hir::TraitItemKind::Const(ty, None) => TyAssocConstItem(clean_ty(ty, cx)),
hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Provided(body)) => {
let m = clean_function(cx, sig, trait_item.generics, body);
MethodItem(m, None)
}
hir::TraitItemKind::Fn(ref sig, hir::TraitFn::Required(names)) => {
let (generics, decl) = enter_impl_trait(cx, |cx| {
// NOTE: generics must be cleaned before args
let generics = clean_generics(trait_item.generics, cx);
let args = clean_args_from_types_and_names(cx, sig.decl.inputs, names);
let decl = clean_fn_decl_with_args(cx, sig.decl, args);
(generics, decl)
});
TyMethodItem(Box::new(Function { decl, generics }))
}
hir::TraitItemKind::Type(bounds, Some(default)) => {
let generics = enter_impl_trait(cx, |cx| clean_generics(trait_item.generics, cx));
let bounds = bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect();
let item_type = clean_middle_ty(hir_ty_to_ty(cx.tcx, default), cx, None);
AssocTypeItem(
Box::new(Typedef {
type_: clean_ty(default, cx),
generics,
item_type: Some(item_type),
}),
bounds,
)
}
hir::TraitItemKind::Type(bounds, None) => {
let generics = enter_impl_trait(cx, |cx| clean_generics(trait_item.generics, cx));
let bounds = bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect();
TyAssocTypeItem(Box::new(generics), bounds)
}
};
let what_rustc_thinks =
Item::from_def_id_and_parts(local_did, Some(trait_item.ident.name), inner, cx);
// Trait items always inherit the trait's visibility -- we don't want to show `pub`.
Item { visibility: Inherited, ..what_rustc_thinks }
})
}
pub(crate) fn clean_impl_item<'tcx>(
impl_: &hir::ImplItem<'tcx>,
cx: &mut DocContext<'tcx>,
) -> Item {
let local_did = impl_.owner_id.to_def_id();
cx.with_param_env(local_did, |cx| {
let inner = match impl_.kind {
hir::ImplItemKind::Const(ty, expr) => {
let default = ConstantKind::Local { def_id: local_did, body: expr };
AssocConstItem(clean_ty(ty, cx), default)
}
hir::ImplItemKind::Fn(ref sig, body) => {
let m = clean_function(cx, sig, impl_.generics, body);
let defaultness = cx.tcx.impl_defaultness(impl_.owner_id);
MethodItem(m, Some(defaultness))
}
hir::ImplItemKind::Type(hir_ty) => {
let type_ = clean_ty(hir_ty, cx);
let generics = clean_generics(impl_.generics, cx);
let item_type = clean_middle_ty(hir_ty_to_ty(cx.tcx, hir_ty), cx, None);
AssocTypeItem(
Box::new(Typedef { type_, generics, item_type: Some(item_type) }),
Vec::new(),
)
}
};
let mut what_rustc_thinks =
Item::from_def_id_and_parts(local_did, Some(impl_.ident.name), inner, cx);
let impl_ref = cx.tcx.impl_trait_ref(cx.tcx.local_parent(impl_.owner_id.def_id));
// Trait impl items always inherit the impl's visibility --
// we don't want to show `pub`.
if impl_ref.is_some() {
what_rustc_thinks.visibility = Inherited;
}
what_rustc_thinks
})
}
pub(crate) fn clean_middle_assoc_item<'tcx>(
assoc_item: &ty::AssocItem,
cx: &mut DocContext<'tcx>,
) -> Item {
let tcx = cx.tcx;
let kind = match assoc_item.kind {
ty::AssocKind::Const => {
let ty = clean_middle_ty(tcx.type_of(assoc_item.def_id), cx, Some(assoc_item.def_id));
let provided = match assoc_item.container {
ty::ImplContainer => true,
ty::TraitContainer => tcx.impl_defaultness(assoc_item.def_id).has_value(),
};
if provided {
AssocConstItem(ty, ConstantKind::Extern { def_id: assoc_item.def_id })
} else {
TyAssocConstItem(ty)
}
}
ty::AssocKind::Fn => {
let generics = clean_ty_generics(
cx,
tcx.generics_of(assoc_item.def_id),
tcx.explicit_predicates_of(assoc_item.def_id),
);
let sig = tcx.fn_sig(assoc_item.def_id);
let mut decl = clean_fn_decl_from_did_and_sig(cx, Some(assoc_item.def_id), sig);
if assoc_item.fn_has_self_parameter {
let self_ty = match assoc_item.container {
ty::ImplContainer => tcx.type_of(assoc_item.container_id(tcx)),
ty::TraitContainer => tcx.types.self_param,
};
let self_arg_ty = sig.input(0).skip_binder();
if self_arg_ty == self_ty {
decl.inputs.values[0].type_ = Generic(kw::SelfUpper);
} else if let ty::Ref(_, ty, _) = *self_arg_ty.kind() {
if ty == self_ty {
match decl.inputs.values[0].type_ {
BorrowedRef { ref mut type_, .. } => **type_ = Generic(kw::SelfUpper),
_ => unreachable!(),
}
}
}
}
let provided = match assoc_item.container {
ty::ImplContainer => true,
ty::TraitContainer => assoc_item.defaultness(tcx).has_value(),
};
if provided {
let defaultness = match assoc_item.container {
ty::ImplContainer => Some(assoc_item.defaultness(tcx)),
ty::TraitContainer => None,
};
MethodItem(Box::new(Function { generics, decl }), defaultness)
} else {
TyMethodItem(Box::new(Function { generics, decl }))
}
}
ty::AssocKind::Type => {
let my_name = assoc_item.name;
fn param_eq_arg(param: &GenericParamDef, arg: &GenericArg) -> bool {
match (&param.kind, arg) {
(GenericParamDefKind::Type { .. }, GenericArg::Type(Type::Generic(ty)))
if *ty == param.name =>
{
true
}
(GenericParamDefKind::Lifetime { .. }, GenericArg::Lifetime(Lifetime(lt)))
if *lt == param.name =>
{
true
}
(GenericParamDefKind::Const { .. }, GenericArg::Const(c)) => match &c.kind {
ConstantKind::TyConst { expr } => expr == param.name.as_str(),
_ => false,
},
_ => false,
}
}
if let ty::TraitContainer = assoc_item.container {
let bounds = tcx.explicit_item_bounds(assoc_item.def_id);
let predicates = tcx.explicit_predicates_of(assoc_item.def_id).predicates;
let predicates =
tcx.arena.alloc_from_iter(bounds.into_iter().chain(predicates).copied());
let mut generics = clean_ty_generics(
cx,
tcx.generics_of(assoc_item.def_id),
ty::GenericPredicates { parent: None, predicates },
);
// Move bounds that are (likely) directly attached to the associated type
// from the where clause to the associated type.
// There is no guarantee that this is what the user actually wrote but we have
// no way of knowing.
let mut bounds = generics
.where_predicates
.drain_filter(|pred| match *pred {
WherePredicate::BoundPredicate {
ty: QPath(box QPathData { ref assoc, ref self_type, ref trait_, .. }),
..
} => {
if assoc.name != my_name {
return false;
}
if trait_.def_id() != assoc_item.container_id(tcx) {
return false;
}
match *self_type {
Generic(ref s) if *s == kw::SelfUpper => {}
_ => return false,
}
match &assoc.args {
GenericArgs::AngleBracketed { args, bindings } => {
if !bindings.is_empty()
|| generics
.params
.iter()
.zip(args.iter())
.any(|(param, arg)| !param_eq_arg(param, arg))
{
return false;
}
}
GenericArgs::Parenthesized { .. } => {
// The only time this happens is if we're inside the rustdoc for Fn(),
// which only has one associated type, which is not a GAT, so whatever.
}
}
true
}
_ => false,
})
.flat_map(|pred| {
if let WherePredicate::BoundPredicate { bounds, .. } = pred {
bounds
} else {
unreachable!()
}
})
.collect::<Vec<_>>();
// Our Sized/?Sized bound didn't get handled when creating the generics
// because we didn't actually get our whole set of bounds until just now
// (some of them may have come from the trait). If we do have a sized
// bound, we remove it, and if we don't then we add the `?Sized` bound
// at the end.
match bounds.iter().position(|b| b.is_sized_bound(cx)) {
Some(i) => {
bounds.remove(i);
}
None => bounds.push(GenericBound::maybe_sized(cx)),
}
// Move bounds that are (likely) directly attached to the parameters of the
// (generic) associated type from the where clause to the respective parameter.
// There is no guarantee that this is what the user actually wrote but we have
// no way of knowing.
let mut where_predicates = Vec::new();
for mut pred in generics.where_predicates {
if let WherePredicate::BoundPredicate { ty: Generic(arg), bounds, .. } = &mut pred
&& let Some(GenericParamDef {
kind: GenericParamDefKind::Type { bounds: param_bounds, .. },
..
}) = generics.params.iter_mut().find(|param| &param.name == arg)
{
param_bounds.extend(mem::take(bounds));
} else {
where_predicates.push(pred);
}
}
generics.where_predicates = where_predicates;
if tcx.impl_defaultness(assoc_item.def_id).has_value() {
AssocTypeItem(
Box::new(Typedef {
type_: clean_middle_ty(
tcx.type_of(assoc_item.def_id),
cx,
Some(assoc_item.def_id),
),
generics,
// FIXME: should we obtain the Type from HIR and pass it on here?
item_type: None,
}),
bounds,
)
} else {
TyAssocTypeItem(Box::new(generics), bounds)
}
} else {
// FIXME: when could this happen? Associated items in inherent impls?
AssocTypeItem(
Box::new(Typedef {
type_: clean_middle_ty(
tcx.type_of(assoc_item.def_id),
cx,
Some(assoc_item.def_id),
),
generics: Generics { params: Vec::new(), where_predicates: Vec::new() },
item_type: None,
}),
Vec::new(),
)
}
}
};
let mut what_rustc_thinks =
Item::from_def_id_and_parts(assoc_item.def_id, Some(assoc_item.name), kind, cx);
let impl_ref = tcx.impl_trait_ref(tcx.parent(assoc_item.def_id));
// Trait impl items always inherit the impl's visibility --
// we don't want to show `pub`.
if impl_ref.is_some() {
what_rustc_thinks.visibility = Visibility::Inherited;
}
what_rustc_thinks
}
fn clean_qpath<'tcx>(hir_ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> Type {
let hir::Ty { hir_id: _, span, ref kind } = *hir_ty;
let hir::TyKind::Path(qpath) = kind else { unreachable!() };
match qpath {
hir::QPath::Resolved(None, path) => {
if let Res::Def(DefKind::TyParam, did) = path.res {
if let Some(new_ty) = cx.substs.get(&did).and_then(|p| p.as_ty()).cloned() {
return new_ty;
}
if let Some(bounds) = cx.impl_trait_bounds.remove(&did.into()) {
return ImplTrait(bounds);
}
}
if let Some(expanded) = maybe_expand_private_type_alias(cx, path) {
expanded
} else {
let path = clean_path(path, cx);
resolve_type(cx, path)
}
}
hir::QPath::Resolved(Some(qself), p) => {
// Try to normalize `<X as Y>::T` to a type
let ty = hir_ty_to_ty(cx.tcx, hir_ty);
if let Some(normalized_value) = normalize(cx, ty) {
return clean_middle_ty(normalized_value, cx, None);
}
let trait_segments = &p.segments[..p.segments.len() - 1];
let trait_def = cx.tcx.associated_item(p.res.def_id()).container_id(cx.tcx);
let trait_ = self::Path {
res: Res::Def(DefKind::Trait, trait_def),
segments: trait_segments.iter().map(|x| clean_path_segment(x, cx)).collect(),
};
register_res(cx, trait_.res);
let self_def_id = DefId::local(qself.hir_id.owner.def_id.local_def_index);
let self_type = clean_ty(qself, cx);
let should_show_cast = compute_should_show_cast(Some(self_def_id), &trait_, &self_type);
Type::QPath(Box::new(QPathData {
assoc: clean_path_segment(p.segments.last().expect("segments were empty"), cx),
should_show_cast,
self_type,
trait_,
}))
}
hir::QPath::TypeRelative(qself, segment) => {
let ty = hir_ty_to_ty(cx.tcx, hir_ty);
let res = match ty.kind() {
ty::Projection(proj) => Res::Def(DefKind::Trait, proj.trait_ref(cx.tcx).def_id),
// Rustdoc handles `ty::Error`s by turning them into `Type::Infer`s.
ty::Error(_) => return Type::Infer,
_ => bug!("clean: expected associated type, found `{:?}`", ty),
};
let trait_ = clean_path(&hir::Path { span, res, segments: &[] }, cx);
register_res(cx, trait_.res);
let self_def_id = res.opt_def_id();
let self_type = clean_ty(qself, cx);
let should_show_cast = compute_should_show_cast(self_def_id, &trait_, &self_type);
Type::QPath(Box::new(QPathData {
assoc: clean_path_segment(segment, cx),
should_show_cast,
self_type,
trait_,
}))
}
hir::QPath::LangItem(..) => bug!("clean: requiring documentation of lang item"),
}
}
fn maybe_expand_private_type_alias<'tcx>(
cx: &mut DocContext<'tcx>,
path: &hir::Path<'tcx>,
) -> Option<Type> {
let Res::Def(DefKind::TyAlias, def_id) = path.res else { return None };
// Substitute private type aliases
let def_id = def_id.as_local()?;
let alias = if !cx.cache.effective_visibilities.is_exported(def_id.to_def_id()) {
&cx.tcx.hir().expect_item(def_id).kind
} else {
return None;
};
let hir::ItemKind::TyAlias(ty, generics) = alias else { return None };
let provided_params = &path.segments.last().expect("segments were empty");
let mut substs = FxHashMap::default();
let generic_args = provided_params.args();
let mut indices: hir::GenericParamCount = Default::default();
for param in generics.params.iter() {
match param.kind {
hir::GenericParamKind::Lifetime { .. } => {
let mut j = 0;
let lifetime = generic_args.args.iter().find_map(|arg| match arg {
hir::GenericArg::Lifetime(lt) => {
if indices.lifetimes == j {
return Some(lt);
}
j += 1;
None
}
_ => None,
});
if let Some(lt) = lifetime {
let lt_def_id = cx.tcx.hir().local_def_id(param.hir_id);
let cleaned =
if !lt.is_elided() { clean_lifetime(lt, cx) } else { Lifetime::elided() };
substs.insert(lt_def_id.to_def_id(), SubstParam::Lifetime(cleaned));
}
indices.lifetimes += 1;
}
hir::GenericParamKind::Type { ref default, .. } => {
let ty_param_def_id = cx.tcx.hir().local_def_id(param.hir_id);
let mut j = 0;
let type_ = generic_args.args.iter().find_map(|arg| match arg {
hir::GenericArg::Type(ty) => {
if indices.types == j {
return Some(ty);
}
j += 1;
None
}
_ => None,
});
if let Some(ty) = type_ {
substs.insert(ty_param_def_id.to_def_id(), SubstParam::Type(clean_ty(ty, cx)));
} else if let Some(default) = *default {
substs.insert(
ty_param_def_id.to_def_id(),
SubstParam::Type(clean_ty(default, cx)),
);
}
indices.types += 1;
}
hir::GenericParamKind::Const { .. } => {
let const_param_def_id = cx.tcx.hir().local_def_id(param.hir_id);
let mut j = 0;
let const_ = generic_args.args.iter().find_map(|arg| match arg {
hir::GenericArg::Const(ct) => {
if indices.consts == j {
return Some(ct);
}
j += 1;
None
}
_ => None,
});
if let Some(ct) = const_ {
substs.insert(
const_param_def_id.to_def_id(),
SubstParam::Constant(clean_const(ct, cx)),
);
}
// FIXME(const_generics_defaults)
indices.consts += 1;
}
}
}
Some(cx.enter_alias(substs, |cx| clean_ty(ty, cx)))
}
pub(crate) fn clean_ty<'tcx>(ty: &hir::Ty<'tcx>, cx: &mut DocContext<'tcx>) -> Type {
use rustc_hir::*;
match ty.kind {
TyKind::Never => Primitive(PrimitiveType::Never),
TyKind::Ptr(ref m) => RawPointer(m.mutbl, Box::new(clean_ty(m.ty, cx))),
TyKind::Rptr(ref l, ref m) => {
// There are two times a `Fresh` lifetime can be created:
// 1. For `&'_ x`, written by the user. This corresponds to `lower_lifetime` in `rustc_ast_lowering`.
// 2. For `&x` as a parameter to an `async fn`. This corresponds to `elided_ref_lifetime in `rustc_ast_lowering`.
// See #59286 for more information.
// Ideally we would only hide the `'_` for case 2., but I don't know a way to distinguish it.
// Turning `fn f(&'_ self)` into `fn f(&self)` isn't the worst thing in the world, though;
// there's no case where it could cause the function to fail to compile.
let elided =
l.is_elided() || matches!(l.name, LifetimeName::Param(_, ParamName::Fresh));
let lifetime = if elided { None } else { Some(clean_lifetime(*l, cx)) };
BorrowedRef { lifetime, mutability: m.mutbl, type_: Box::new(clean_ty(m.ty, cx)) }
}
TyKind::Slice(ty) => Slice(Box::new(clean_ty(ty, cx))),
TyKind::Array(ty, ref length) => {
let length = match length {
hir::ArrayLen::Infer(_, _) => "_".to_string(),
hir::ArrayLen::Body(anon_const) => {
let def_id = cx.tcx.hir().local_def_id(anon_const.hir_id);
// NOTE(min_const_generics): We can't use `const_eval_poly` for constants
// as we currently do not supply the parent generics to anonymous constants
// but do allow `ConstKind::Param`.
//
// `const_eval_poly` tries to first substitute generic parameters which
// results in an ICE while manually constructing the constant and using `eval`
// does nothing for `ConstKind::Param`.
let ct = ty::Const::from_anon_const(cx.tcx, def_id);
let param_env = cx.tcx.param_env(def_id);
print_const(cx, ct.eval(cx.tcx, param_env))
}
};
Array(Box::new(clean_ty(ty, cx)), length)
}
TyKind::Tup(tys) => Tuple(tys.iter().map(|ty| clean_ty(ty, cx)).collect()),
TyKind::OpaqueDef(item_id, _, _) => {
let item = cx.tcx.hir().item(item_id);
if let hir::ItemKind::OpaqueTy(ref ty) = item.kind {
ImplTrait(ty.bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect())
} else {
unreachable!()
}
}
TyKind::Path(_) => clean_qpath(ty, cx),
TyKind::TraitObject(bounds, ref lifetime, _) => {
let bounds = bounds.iter().map(|bound| clean_poly_trait_ref(bound, cx)).collect();
let lifetime =
if !lifetime.is_elided() { Some(clean_lifetime(*lifetime, cx)) } else { None };
DynTrait(bounds, lifetime)
}
TyKind::BareFn(barefn) => BareFunction(Box::new(clean_bare_fn_ty(barefn, cx))),
// Rustdoc handles `TyKind::Err`s by turning them into `Type::Infer`s.
TyKind::Infer | TyKind::Err | TyKind::Typeof(..) => Infer,
}
}
/// Returns `None` if the type could not be normalized
fn normalize<'tcx>(cx: &mut DocContext<'tcx>, ty: Ty<'tcx>) -> Option<Ty<'tcx>> {
// HACK: low-churn fix for #79459 while we wait for a trait normalization fix
if !cx.tcx.sess.opts.unstable_opts.normalize_docs {
return None;
}
use crate::rustc_trait_selection::infer::TyCtxtInferExt;
use crate::rustc_trait_selection::traits::query::normalize::AtExt;
use rustc_middle::traits::ObligationCause;
// Try to normalize `<X as Y>::T` to a type
let infcx = cx.tcx.infer_ctxt().build();
let normalized = infcx
.at(&ObligationCause::dummy(), cx.param_env)
.normalize(ty)
.map(|resolved| infcx.resolve_vars_if_possible(resolved.value));
match normalized {
Ok(normalized_value) => {
debug!("normalized {:?} to {:?}", ty, normalized_value);
Some(normalized_value)
}
Err(err) => {
debug!("failed to normalize {:?}: {:?}", ty, err);
None
}
}
}
pub(crate) fn clean_middle_ty<'tcx>(
ty: Ty<'tcx>,
cx: &mut DocContext<'tcx>,
def_id: Option<DefId>,
) -> Type {
trace!("cleaning type: {:?}", ty);
let ty = normalize(cx, ty).unwrap_or(ty);
match *ty.kind() {
ty::Never => Primitive(PrimitiveType::Never),
ty::Bool => Primitive(PrimitiveType::Bool),
ty::Char => Primitive(PrimitiveType::Char),
ty::Int(int_ty) => Primitive(int_ty.into()),
ty::Uint(uint_ty) => Primitive(uint_ty.into()),
ty::Float(float_ty) => Primitive(float_ty.into()),
ty::Str => Primitive(PrimitiveType::Str),
ty::Slice(ty) => Slice(Box::new(clean_middle_ty(ty, cx, None))),
ty::Array(ty, mut n) => {
n = n.eval(cx.tcx, ty::ParamEnv::reveal_all());
let n = print_const(cx, n);
Array(Box::new(clean_middle_ty(ty, cx, None)), n)
}
ty::RawPtr(mt) => RawPointer(mt.mutbl, Box::new(clean_middle_ty(mt.ty, cx, None))),
ty::Ref(r, ty, mutbl) => BorrowedRef {
lifetime: clean_middle_region(r),
mutability: mutbl,
type_: Box::new(clean_middle_ty(ty, cx, None)),
},
ty::FnDef(..) | ty::FnPtr(_) => {
let sig = ty.fn_sig(cx.tcx);
let decl = clean_fn_decl_from_did_and_sig(cx, None, sig);
BareFunction(Box::new(BareFunctionDecl {
unsafety: sig.unsafety(),
generic_params: Vec::new(),
decl,
abi: sig.abi(),
}))
}
ty::Adt(def, substs) => {
let did = def.did();
let kind = match def.adt_kind() {
AdtKind::Struct => ItemType::Struct,
AdtKind::Union => ItemType::Union,
AdtKind::Enum => ItemType::Enum,
};
inline::record_extern_fqn(cx, did, kind);
let path = external_path(cx, did, false, ThinVec::new(), substs);
Type::Path { path }
}
ty::Foreign(did) => {
inline::record_extern_fqn(cx, did, ItemType::ForeignType);
let path = external_path(cx, did, false, ThinVec::new(), InternalSubsts::empty());
Type::Path { path }
}
ty::Dynamic(obj, ref reg, _) => {
// HACK: pick the first `did` as the `did` of the trait object. Someone
// might want to implement "native" support for marker-trait-only
// trait objects.
let mut dids = obj.auto_traits();
let did = obj
.principal_def_id()
.or_else(|| dids.next())
.unwrap_or_else(|| panic!("found trait object `{:?}` with no traits?", ty));
let substs = match obj.principal() {
Some(principal) => principal.skip_binder().substs,
// marker traits have no substs.
_ => cx.tcx.intern_substs(&[]),
};
inline::record_extern_fqn(cx, did, ItemType::Trait);
let lifetime = clean_middle_region(*reg);
let mut bounds = dids
.map(|did| {
let empty = cx.tcx.intern_substs(&[]);
let path = external_path(cx, did, false, ThinVec::new(), empty);
inline::record_extern_fqn(cx, did, ItemType::Trait);
PolyTrait { trait_: path, generic_params: Vec::new() }
})
.collect::<Vec<_>>();
let bindings = obj
.projection_bounds()
.map(|pb| TypeBinding {
assoc: projection_to_path_segment(
pb.skip_binder()
// HACK(compiler-errors): Doesn't actually matter what self
// type we put here, because we're only using the GAT's substs.
.with_self_ty(cx.tcx, cx.tcx.types.self_param)
.projection_ty,
cx,
),
kind: TypeBindingKind::Equality {
term: clean_middle_term(pb.skip_binder().term, cx),
},
})
.collect();
let path = external_path(cx, did, false, bindings, substs);
bounds.insert(0, PolyTrait { trait_: path, generic_params: Vec::new() });
DynTrait(bounds, lifetime)
}
ty::Tuple(t) => Tuple(t.iter().map(|t| clean_middle_ty(t, cx, None)).collect()),
ty::Projection(ref data) => clean_projection(*data, cx, def_id),
ty::Param(ref p) => {
if let Some(bounds) = cx.impl_trait_bounds.remove(&p.index.into()) {
ImplTrait(bounds)
} else {
Generic(p.name)
}
}
ty::Opaque(def_id, substs) => {
// Grab the "TraitA + TraitB" from `impl TraitA + TraitB`,
// by looking up the bounds associated with the def_id.
let bounds = cx
.tcx
.explicit_item_bounds(def_id)
.iter()
.map(|(bound, _)| EarlyBinder(*bound).subst(cx.tcx, substs))
.collect::<Vec<_>>();
clean_middle_opaque_bounds(cx, bounds)
}
ty::Closure(..) => panic!("Closure"),
ty::Generator(..) => panic!("Generator"),
ty::Bound(..) => panic!("Bound"),
ty::Placeholder(..) => panic!("Placeholder"),
ty::GeneratorWitness(..) => panic!("GeneratorWitness"),
ty::Infer(..) => panic!("Infer"),
ty::Error(_) => panic!("Error"),
}
}
fn clean_middle_opaque_bounds<'tcx>(
cx: &mut DocContext<'tcx>,
bounds: Vec<ty::Predicate<'tcx>>,
) -> Type {
let mut regions = vec![];
let mut has_sized = false;
let mut bounds = bounds
.iter()
.filter_map(|bound| {
let bound_predicate = bound.kind();
let trait_ref = match bound_predicate.skip_binder() {
ty::PredicateKind::Trait(tr) => bound_predicate.rebind(tr.trait_ref),
ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(_ty, reg)) => {
if let Some(r) = clean_middle_region(reg) {
regions.push(GenericBound::Outlives(r));
}
return None;
}
_ => return None,
};
if let Some(sized) = cx.tcx.lang_items().sized_trait() {
if trait_ref.def_id() == sized {
has_sized = true;
return None;
}
}
let bindings: ThinVec<_> = bounds
.iter()
.filter_map(|bound| {
if let ty::PredicateKind::Projection(proj) = bound.kind().skip_binder() {
if proj.projection_ty.trait_ref(cx.tcx) == trait_ref.skip_binder() {
Some(TypeBinding {
assoc: projection_to_path_segment(proj.projection_ty, cx),
kind: TypeBindingKind::Equality {
term: clean_middle_term(proj.term, cx),
},
})
} else {
None
}
} else {
None
}
})
.collect();
Some(clean_poly_trait_ref_with_bindings(cx, trait_ref, bindings))
})
.collect::<Vec<_>>();
bounds.extend(regions);
if !has_sized && !bounds.is_empty() {
bounds.insert(0, GenericBound::maybe_sized(cx));
}
ImplTrait(bounds)
}
pub(crate) fn clean_field<'tcx>(field: &hir::FieldDef<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
let def_id = cx.tcx.hir().local_def_id(field.hir_id).to_def_id();
clean_field_with_def_id(def_id, field.ident.name, clean_ty(field.ty, cx), cx)
}
pub(crate) fn clean_middle_field<'tcx>(field: &ty::FieldDef, cx: &mut DocContext<'tcx>) -> Item {
clean_field_with_def_id(
field.did,
field.name,
clean_middle_ty(cx.tcx.type_of(field.did), cx, Some(field.did)),
cx,
)
}
pub(crate) fn clean_field_with_def_id(
def_id: DefId,
name: Symbol,
ty: Type,
cx: &mut DocContext<'_>,
) -> Item {
let what_rustc_thinks =
Item::from_def_id_and_parts(def_id, Some(name), StructFieldItem(ty), cx);
if is_field_vis_inherited(cx.tcx, def_id) {
// Variant fields inherit their enum's visibility.
Item { visibility: Visibility::Inherited, ..what_rustc_thinks }
} else {
what_rustc_thinks
}
}
fn is_field_vis_inherited(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
let parent = tcx.parent(def_id);
match tcx.def_kind(parent) {
DefKind::Struct | DefKind::Union => false,
DefKind::Variant => true,
parent_kind => panic!("unexpected parent kind: {:?}", parent_kind),
}
}
pub(crate) fn clean_visibility(vis: ty::Visibility<DefId>) -> Visibility {
match vis {
ty::Visibility::Public => Visibility::Public,
ty::Visibility::Restricted(module) => Visibility::Restricted(module),
}
}
pub(crate) fn clean_variant_def<'tcx>(variant: &ty::VariantDef, cx: &mut DocContext<'tcx>) -> Item {
let kind = match variant.ctor_kind {
CtorKind::Const => Variant::CLike(match variant.discr {
ty::VariantDiscr::Explicit(def_id) => Some(Discriminant { expr: None, value: def_id }),
ty::VariantDiscr::Relative(_) => None,
}),
CtorKind::Fn => Variant::Tuple(
variant.fields.iter().map(|field| clean_middle_field(field, cx)).collect(),
),
CtorKind::Fictive => Variant::Struct(VariantStruct {
struct_type: CtorKind::Fictive,
fields: variant.fields.iter().map(|field| clean_middle_field(field, cx)).collect(),
}),
};
let what_rustc_thinks =
Item::from_def_id_and_parts(variant.def_id, Some(variant.name), VariantItem(kind), cx);
// don't show `pub` for variants, which always inherit visibility
Item { visibility: Inherited, ..what_rustc_thinks }
}
fn clean_variant_data<'tcx>(
variant: &hir::VariantData<'tcx>,
disr_expr: &Option<hir::AnonConst>,
cx: &mut DocContext<'tcx>,
) -> Variant {
match variant {
hir::VariantData::Struct(..) => Variant::Struct(VariantStruct {
struct_type: CtorKind::from_hir(variant),
fields: variant.fields().iter().map(|x| clean_field(x, cx)).collect(),
}),
hir::VariantData::Tuple(..) => {
Variant::Tuple(variant.fields().iter().map(|x| clean_field(x, cx)).collect())
}
hir::VariantData::Unit(..) => Variant::CLike(disr_expr.map(|disr| Discriminant {
expr: Some(disr.body),
value: cx.tcx.hir().local_def_id(disr.hir_id).to_def_id(),
})),
}
}
fn clean_path<'tcx>(path: &hir::Path<'tcx>, cx: &mut DocContext<'tcx>) -> Path {
Path {
res: path.res,
segments: path.segments.iter().map(|x| clean_path_segment(x, cx)).collect(),
}
}
fn clean_generic_args<'tcx>(
generic_args: &hir::GenericArgs<'tcx>,
cx: &mut DocContext<'tcx>,
) -> GenericArgs {
if generic_args.parenthesized {
let output = clean_ty(generic_args.bindings[0].ty(), cx);
let output = if output != Type::Tuple(Vec::new()) { Some(Box::new(output)) } else { None };
let inputs =
generic_args.inputs().iter().map(|x| clean_ty(x, cx)).collect::<Vec<_>>().into();
GenericArgs::Parenthesized { inputs, output }
} else {
let args = generic_args
.args
.iter()
.map(|arg| match arg {
hir::GenericArg::Lifetime(lt) if !lt.is_elided() => {
GenericArg::Lifetime(clean_lifetime(*lt, cx))
}
hir::GenericArg::Lifetime(_) => GenericArg::Lifetime(Lifetime::elided()),
hir::GenericArg::Type(ty) => GenericArg::Type(clean_ty(ty, cx)),
hir::GenericArg::Const(ct) => GenericArg::Const(Box::new(clean_const(ct, cx))),
hir::GenericArg::Infer(_inf) => GenericArg::Infer,
})
.collect::<Vec<_>>()
.into();
let bindings =
generic_args.bindings.iter().map(|x| clean_type_binding(x, cx)).collect::<ThinVec<_>>();
GenericArgs::AngleBracketed { args, bindings }
}
}
fn clean_path_segment<'tcx>(
path: &hir::PathSegment<'tcx>,
cx: &mut DocContext<'tcx>,
) -> PathSegment {
PathSegment { name: path.ident.name, args: clean_generic_args(path.args(), cx) }
}
fn clean_bare_fn_ty<'tcx>(
bare_fn: &hir::BareFnTy<'tcx>,
cx: &mut DocContext<'tcx>,
) -> BareFunctionDecl {
let (generic_params, decl) = enter_impl_trait(cx, |cx| {
// NOTE: generics must be cleaned before args
let generic_params = bare_fn
.generic_params
.iter()
.filter(|p| !is_elided_lifetime(p))
.map(|x| clean_generic_param(cx, None, x))
.collect();
let args = clean_args_from_types_and_names(cx, bare_fn.decl.inputs, bare_fn.param_names);
let decl = clean_fn_decl_with_args(cx, bare_fn.decl, args);
(generic_params, decl)
});
BareFunctionDecl { unsafety: bare_fn.unsafety, abi: bare_fn.abi, decl, generic_params }
}
fn clean_maybe_renamed_item<'tcx>(
cx: &mut DocContext<'tcx>,
item: &hir::Item<'tcx>,
renamed: Option<Symbol>,
) -> Vec<Item> {
use hir::ItemKind;
let def_id = item.owner_id.to_def_id();
let mut name = renamed.unwrap_or_else(|| cx.tcx.hir().name(item.hir_id()));
cx.with_param_env(def_id, |cx| {
let kind = match item.kind {
ItemKind::Static(ty, mutability, body_id) => {
StaticItem(Static { type_: clean_ty(ty, cx), mutability, expr: Some(body_id) })
}
ItemKind::Const(ty, body_id) => ConstantItem(Constant {
type_: clean_ty(ty, cx),
kind: ConstantKind::Local { body: body_id, def_id },
}),
ItemKind::OpaqueTy(ref ty) => OpaqueTyItem(OpaqueTy {
bounds: ty.bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect(),
generics: clean_generics(ty.generics, cx),
}),
ItemKind::TyAlias(hir_ty, generics) => {
let rustdoc_ty = clean_ty(hir_ty, cx);
let ty = clean_middle_ty(hir_ty_to_ty(cx.tcx, hir_ty), cx, None);
TypedefItem(Box::new(Typedef {
type_: rustdoc_ty,
generics: clean_generics(generics, cx),
item_type: Some(ty),
}))
}
ItemKind::Enum(ref def, generics) => EnumItem(Enum {
variants: def.variants.iter().map(|v| clean_variant(v, cx)).collect(),
generics: clean_generics(generics, cx),
}),
ItemKind::TraitAlias(generics, bounds) => TraitAliasItem(TraitAlias {
generics: clean_generics(generics, cx),
bounds: bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect(),
}),
ItemKind::Union(ref variant_data, generics) => UnionItem(Union {
generics: clean_generics(generics, cx),
fields: variant_data.fields().iter().map(|x| clean_field(x, cx)).collect(),
}),
ItemKind::Struct(ref variant_data, generics) => StructItem(Struct {
struct_type: CtorKind::from_hir(variant_data),
generics: clean_generics(generics, cx),
fields: variant_data.fields().iter().map(|x| clean_field(x, cx)).collect(),
}),
ItemKind::Impl(impl_) => return clean_impl(impl_, item.hir_id(), cx),
// proc macros can have a name set by attributes
ItemKind::Fn(ref sig, generics, body_id) => {
clean_fn_or_proc_macro(item, sig, generics, body_id, &mut name, cx)
}
ItemKind::Macro(ref macro_def, _) => {
let ty_vis = clean_visibility(cx.tcx.visibility(def_id));
MacroItem(Macro {
source: display_macro_source(cx, name, macro_def, def_id, ty_vis),
})
}
ItemKind::Trait(_, _, generics, bounds, item_ids) => {
let items = item_ids
.iter()
.map(|ti| clean_trait_item(cx.tcx.hir().trait_item(ti.id), cx))
.collect();
TraitItem(Box::new(Trait {
def_id,
items,
generics: clean_generics(generics, cx),
bounds: bounds.iter().filter_map(|x| clean_generic_bound(x, cx)).collect(),
}))
}
ItemKind::ExternCrate(orig_name) => {
return clean_extern_crate(item, name, orig_name, cx);
}
ItemKind::Use(path, kind) => {
return clean_use_statement(item, name, path, kind, cx, &mut FxHashSet::default());
}
_ => unreachable!("not yet converted"),
};
vec![Item::from_def_id_and_parts(def_id, Some(name), kind, cx)]
})
}
fn clean_variant<'tcx>(variant: &hir::Variant<'tcx>, cx: &mut DocContext<'tcx>) -> Item {
let kind = VariantItem(clean_variant_data(&variant.data, &variant.disr_expr, cx));
let what_rustc_thinks =
Item::from_hir_id_and_parts(variant.id, Some(variant.ident.name), kind, cx);
// don't show `pub` for variants, which are always public
Item { visibility: Inherited, ..what_rustc_thinks }
}
fn clean_impl<'tcx>(
impl_: &hir::Impl<'tcx>,
hir_id: hir::HirId,
cx: &mut DocContext<'tcx>,
) -> Vec<Item> {
let tcx = cx.tcx;
let mut ret = Vec::new();
let trait_ = impl_.of_trait.as_ref().map(|t| clean_trait_ref(t, cx));
let items = impl_
.items
.iter()
.map(|ii| clean_impl_item(tcx.hir().impl_item(ii.id), cx))
.collect::<Vec<_>>();
let def_id = tcx.hir().local_def_id(hir_id);
// If this impl block is an implementation of the Deref trait, then we
// need to try inlining the target's inherent impl blocks as well.
if trait_.as_ref().map(|t| t.def_id()) == tcx.lang_items().deref_trait() {
build_deref_target_impls(cx, &items, &mut ret);
}
let for_ = clean_ty(impl_.self_ty, cx);
let type_alias = for_.def_id(&cx.cache).and_then(|did| match tcx.def_kind(did) {
DefKind::TyAlias => Some(clean_middle_ty(tcx.type_of(did), cx, Some(did))),
_ => None,
});
let mut make_item = |trait_: Option<Path>, for_: Type, items: Vec<Item>| {
let kind = ImplItem(Box::new(Impl {
unsafety: impl_.unsafety,
generics: clean_generics(impl_.generics, cx),
trait_,
for_,
items,
polarity: tcx.impl_polarity(def_id),
kind: if utils::has_doc_flag(tcx, def_id.to_def_id(), sym::fake_variadic) {
ImplKind::FakeVaradic
} else {
ImplKind::Normal
},
}));
Item::from_hir_id_and_parts(hir_id, None, kind, cx)
};
if let Some(type_alias) = type_alias {
ret.push(make_item(trait_.clone(), type_alias, items.clone()));
}
ret.push(make_item(trait_, for_, items));
ret
}
fn clean_extern_crate<'tcx>(
krate: &hir::Item<'tcx>,
name: Symbol,
orig_name: Option<Symbol>,
cx: &mut DocContext<'tcx>,
) -> Vec<Item> {
// this is the ID of the `extern crate` statement
let cnum = cx.tcx.extern_mod_stmt_cnum(krate.owner_id.def_id).unwrap_or(LOCAL_CRATE);
// this is the ID of the crate itself
let crate_def_id = cnum.as_def_id();
let attrs = cx.tcx.hir().attrs(krate.hir_id());
let ty_vis = cx.tcx.visibility(krate.owner_id);
let please_inline = ty_vis.is_public()
&& attrs.iter().any(|a| {
a.has_name(sym::doc)
&& match a.meta_item_list() {
Some(l) => attr::list_contains_name(&l, sym::inline),
None => false,
}
});
if please_inline {
let mut visited = FxHashSet::default();
let res = Res::Def(DefKind::Mod, crate_def_id);
if let Some(items) = inline::try_inline(
cx,
cx.tcx.parent_module(krate.hir_id()).to_def_id(),
Some(krate.owner_id.to_def_id()),
res,
name,
Some(attrs),
&mut visited,
) {
return items;
}
}
// FIXME: using `from_def_id_and_kind` breaks `rustdoc/masked` for some reason
vec![Item {
name: Some(name),
attrs: Box::new(Attributes::from_ast(attrs)),
item_id: crate_def_id.into(),
visibility: clean_visibility(ty_vis),
kind: Box::new(ExternCrateItem { src: orig_name }),
cfg: attrs.cfg(cx.tcx, &cx.cache.hidden_cfg),
}]
}
fn clean_use_statement<'tcx>(
import: &hir::Item<'tcx>,
name: Symbol,
path: &hir::Path<'tcx>,
kind: hir::UseKind,
cx: &mut DocContext<'tcx>,
inlined_names: &mut FxHashSet<(ItemType, Symbol)>,
) -> Vec<Item> {
// We need this comparison because some imports (for std types for example)
// are "inserted" as well but directly by the compiler and they should not be
// taken into account.
if import.span.ctxt().outer_expn_data().kind == ExpnKind::AstPass(AstPass::StdImports) {
return Vec::new();
}
let visibility = cx.tcx.visibility(import.owner_id);
let attrs = cx.tcx.hir().attrs(import.hir_id());
let inline_attr = attrs.lists(sym::doc).get_word_attr(sym::inline);
let pub_underscore = visibility.is_public() && name == kw::Underscore;
let current_mod = cx.tcx.parent_module_from_def_id(import.owner_id.def_id);
// The parent of the module in which this import resides. This
// is the same as `current_mod` if that's already the top
// level module.
let parent_mod = cx.tcx.parent_module_from_def_id(current_mod);
// This checks if the import can be seen from a higher level module.
// In other words, it checks if the visibility is the equivalent of
// `pub(super)` or higher. If the current module is the top level
// module, there isn't really a parent module, which makes the results
// meaningless. In this case, we make sure the answer is `false`.
let is_visible_from_parent_mod =
visibility.is_accessible_from(parent_mod, cx.tcx) && !current_mod.is_top_level_module();
if pub_underscore {
if let Some(ref inline) = inline_attr {
rustc_errors::struct_span_err!(
cx.tcx.sess,
inline.span(),
E0780,
"anonymous imports cannot be inlined"
)
.span_label(import.span, "anonymous import")
.emit();
}
}
// We consider inlining the documentation of `pub use` statements, but we
// forcefully don't inline if this is not public or if the
// #[doc(no_inline)] attribute is present.
// Don't inline doc(hidden) imports so they can be stripped at a later stage.
let mut denied = cx.output_format.is_json()
|| !(visibility.is_public()
|| (cx.render_options.document_private && is_visible_from_parent_mod))
|| pub_underscore
|| attrs.iter().any(|a| {
a.has_name(sym::doc)
&& match a.meta_item_list() {
Some(l) => {
attr::list_contains_name(&l, sym::no_inline)
|| attr::list_contains_name(&l, sym::hidden)
}
None => false,
}
});
// Also check whether imports were asked to be inlined, in case we're trying to re-export a
// crate in Rust 2018+
let path = clean_path(path, cx);
let inner = if kind == hir::UseKind::Glob {
if !denied {
let mut visited = FxHashSet::default();
if let Some(items) = inline::try_inline_glob(cx, path.res, &mut visited, inlined_names)
{
return items;
}
}
Import::new_glob(resolve_use_source(cx, path), true)
} else {
if inline_attr.is_none() {
if let Res::Def(DefKind::Mod, did) = path.res {
if !did.is_local() && did.is_crate_root() {
// if we're `pub use`ing an extern crate root, don't inline it unless we
// were specifically asked for it
denied = true;
}
}
}
if !denied {
let mut visited = FxHashSet::default();
let import_def_id = import.owner_id.to_def_id();
if let Some(mut items) = inline::try_inline(
cx,
cx.tcx.parent_module(import.hir_id()).to_def_id(),
Some(import_def_id),
path.res,
name,
Some(attrs),
&mut visited,
) {
items.push(Item::from_def_id_and_parts(
import_def_id,
None,
ImportItem(Import::new_simple(name, resolve_use_source(cx, path), false)),
cx,
));
return items;
}
}
Import::new_simple(name, resolve_use_source(cx, path), true)
};
vec![Item::from_def_id_and_parts(import.owner_id.to_def_id(), None, ImportItem(inner), cx)]
}
fn clean_maybe_renamed_foreign_item<'tcx>(
cx: &mut DocContext<'tcx>,
item: &hir::ForeignItem<'tcx>,
renamed: Option<Symbol>,
) -> Item {
let def_id = item.owner_id.to_def_id();
cx.with_param_env(def_id, |cx| {
let kind = match item.kind {
hir::ForeignItemKind::Fn(decl, names, generics) => {
let (generics, decl) = enter_impl_trait(cx, |cx| {
// NOTE: generics must be cleaned before args
let generics = clean_generics(generics, cx);
let args = clean_args_from_types_and_names(cx, decl.inputs, names);
let decl = clean_fn_decl_with_args(cx, decl, args);
(generics, decl)
});
ForeignFunctionItem(Box::new(Function { decl, generics }))
}
hir::ForeignItemKind::Static(ty, mutability) => {
ForeignStaticItem(Static { type_: clean_ty(ty, cx), mutability, expr: None })
}
hir::ForeignItemKind::Type => ForeignTypeItem,
};
Item::from_hir_id_and_parts(
item.hir_id(),
Some(renamed.unwrap_or(item.ident.name)),
kind,
cx,
)
})
}
fn clean_type_binding<'tcx>(
type_binding: &hir::TypeBinding<'tcx>,
cx: &mut DocContext<'tcx>,
) -> TypeBinding {
TypeBinding {
assoc: PathSegment {
name: type_binding.ident.name,
args: clean_generic_args(type_binding.gen_args, cx),
},
kind: match type_binding.kind {
hir::TypeBindingKind::Equality { ref term } => {
TypeBindingKind::Equality { term: clean_hir_term(term, cx) }
}
hir::TypeBindingKind::Constraint { bounds } => TypeBindingKind::Constraint {
bounds: bounds.iter().filter_map(|b| clean_generic_bound(b, cx)).collect(),
},
},
}
}