Normalize `<X as Y>::T` for rustdoc
- Only run for `QPath::Resolved` with `Some` self parameter (`<X as Y>::T`) - Fall back to the previous behavior if the path can't be resolved - Show what the behavior is if the type can't be normalized - Run `resolve_vars_if_possible` It's not clear whether or not this is necessary. See https://github.com/rust-lang/rust/pull/77616 for more context. - Add a test for cross-crate re-exports - Use the same code for both `hir::Ty` and `Ty`
This commit is contained in:
parent
7f60ee0ccd
commit
a192e5d9c2
|
@ -1290,6 +1290,7 @@ fn clean_qpath(hir_ty: &hir::Ty<'_>, cx: &DocContext<'_>) -> Type {
|
|||
hir::TyKind::Path(qpath) => qpath,
|
||||
_ => unreachable!(),
|
||||
};
|
||||
|
||||
match qpath {
|
||||
hir::QPath::Resolved(None, ref path) => {
|
||||
if let Res::Def(DefKind::TyParam, did) = path.res {
|
||||
|
@ -1393,6 +1394,12 @@ fn clean_qpath(hir_ty: &hir::Ty<'_>, cx: &DocContext<'_>) -> Type {
|
|||
resolve_type(cx, path.clean(cx), hir_id)
|
||||
}
|
||||
hir::QPath::Resolved(Some(ref qself), ref 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.tcx, ty) {
|
||||
return normalized_value.clean(cx);
|
||||
}
|
||||
|
||||
let segments = if p.is_global() { &p.segments[1..] } else { &p.segments };
|
||||
let trait_segments = &segments[..segments.len() - 1];
|
||||
let trait_path = self::Path {
|
||||
|
@ -1410,18 +1417,12 @@ fn clean_qpath(hir_ty: &hir::Ty<'_>, cx: &DocContext<'_>) -> Type {
|
|||
}
|
||||
}
|
||||
hir::QPath::TypeRelative(ref qself, ref segment) => {
|
||||
let mut res = Res::Err;
|
||||
/*
|
||||
let hir_ty = hir::Ty {
|
||||
kind: hir::TyKind::Path((*qpath).clone()),
|
||||
hir_id,
|
||||
span,
|
||||
};
|
||||
*/
|
||||
let ty = hir_ty_to_ty(cx.tcx, hir_ty);
|
||||
if let ty::Projection(proj) = ty.kind() {
|
||||
res = Res::Def(DefKind::Trait, proj.trait_ref(cx.tcx).def_id);
|
||||
}
|
||||
let res = if let ty::Projection(proj) = ty.kind() {
|
||||
Res::Def(DefKind::Trait, proj.trait_ref(cx.tcx).def_id)
|
||||
} else {
|
||||
Res::Err
|
||||
};
|
||||
let trait_path = hir::Path { span, res, segments: &[] };
|
||||
Type::QPath {
|
||||
name: segment.ident.name.clean(cx),
|
||||
|
@ -1496,10 +1497,42 @@ impl Clean<Type> for hir::Ty<'_> {
|
|||
}
|
||||
}
|
||||
|
||||
/// Returns `None` if the type could not be normalized
|
||||
fn normalize(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Option<Ty<'tcx>> {
|
||||
use crate::rustc_trait_selection::infer::TyCtxtInferExt;
|
||||
use crate::rustc_trait_selection::traits::query::normalize::AtExt;
|
||||
use rustc_middle::traits::ObligationCause;
|
||||
use rustc_middle::ty::ParamEnv;
|
||||
|
||||
// Try to normalize `<X as Y>::T` to a type
|
||||
// FIXME: rustdoc won't be able to perform 'partial' normalization
|
||||
// until this param env is actually correct
|
||||
// 'partial': `<Vec<T> as IntoIterator>::IntoIter>` -> `vec::IntoIter<T>`
|
||||
let param_env = ParamEnv::empty();
|
||||
let lifted = ty.lift_to_tcx(tcx).unwrap();
|
||||
let normalized = tcx.infer_ctxt().enter(|infcx| {
|
||||
infcx
|
||||
.at(&ObligationCause::dummy(), param_env)
|
||||
.normalize(lifted)
|
||||
.map(|resolved| infcx.resolve_vars_if_possible(resolved.value))
|
||||
});
|
||||
match normalized {
|
||||
Ok(normalized_value) => {
|
||||
debug!("resolved {:?} to {:?}", ty, normalized_value);
|
||||
Some(normalized_value)
|
||||
}
|
||||
Err(err) => {
|
||||
debug!("failed to resolve {:?}: {:?}", ty, err);
|
||||
None
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'tcx> Clean<Type> for Ty<'tcx> {
|
||||
fn clean(&self, cx: &DocContext<'_>) -> Type {
|
||||
debug!("cleaning type: {:?}", self);
|
||||
match *self.kind() {
|
||||
let ty = normalize(cx.tcx, self.lift_to_tcx(cx.tcx).unwrap()).unwrap_or(self);
|
||||
match *ty.kind() {
|
||||
ty::Never => Never,
|
||||
ty::Bool => Primitive(PrimitiveType::Bool),
|
||||
ty::Char => Primitive(PrimitiveType::Char),
|
||||
|
|
|
@ -0,0 +1,12 @@
|
|||
#![crate_name = "inner"]
|
||||
pub trait MyTrait {
|
||||
type Y;
|
||||
}
|
||||
|
||||
impl MyTrait for u32 {
|
||||
type Y = i32;
|
||||
}
|
||||
|
||||
pub fn foo() -> <u32 as MyTrait>::Y {
|
||||
0
|
||||
}
|
|
@ -0,0 +1,63 @@
|
|||
// ignore-tidy-linelength
|
||||
// aux-build:normalize-assoc-item.rs
|
||||
// build-aux-docs
|
||||
|
||||
pub trait Trait {
|
||||
type X;
|
||||
}
|
||||
|
||||
impl Trait for usize {
|
||||
type X = isize;
|
||||
}
|
||||
|
||||
// @has 'normalize_assoc_item/fn.f.html' '//pre[@class="rust fn"]' 'pub fn f() -> isize'
|
||||
pub fn f() -> <usize as Trait>::X {
|
||||
0
|
||||
}
|
||||
|
||||
pub struct S {
|
||||
// @has 'normalize_assoc_item/struct.S.html' '//span[@id="structfield.box_me_up"]' 'box_me_up: Box<S>'
|
||||
pub box_me_up: <S as Trait>::X,
|
||||
// @has 'normalize_assoc_item/struct.S.html' '//span[@id="structfield.generic"]' 'generic: (usize, isize)'
|
||||
pub generic: <Generic<usize> as Trait>::X,
|
||||
}
|
||||
|
||||
impl Trait for S {
|
||||
type X = Box<S>;
|
||||
}
|
||||
|
||||
pub struct Generic<Inner>(Inner);
|
||||
|
||||
impl<Inner: Trait> Trait for Generic<Inner> {
|
||||
type X = (Inner, Inner::X);
|
||||
}
|
||||
|
||||
// These can't be normalized because they depend on a generic parameter.
|
||||
// However the user can choose whether the text should be displayed as `Inner::X` or `<Inner as Trait>::X`.
|
||||
|
||||
// @has 'normalize_assoc_item/struct.Unknown.html' '//pre[@class="rust struct"]' 'pub struct Unknown<Inner: Trait>(pub <Inner as Trait>::X);'
|
||||
pub struct Unknown<Inner: Trait>(pub <Inner as Trait>::X);
|
||||
|
||||
// @has 'normalize_assoc_item/struct.Unknown2.html' '//pre[@class="rust struct"]' 'pub struct Unknown2<Inner: Trait>(pub Inner::X);'
|
||||
pub struct Unknown2<Inner: Trait>(pub Inner::X);
|
||||
|
||||
trait Lifetimes<'a> {
|
||||
type Y;
|
||||
}
|
||||
|
||||
impl<'a> Lifetimes<'a> for usize {
|
||||
type Y = &'a isize;
|
||||
}
|
||||
|
||||
// @has 'normalize_assoc_item/fn.g.html' '//pre[@class="rust fn"]' "pub fn g() -> &isize"
|
||||
pub fn g() -> <usize as Lifetimes<'static>>::Y {
|
||||
&0
|
||||
}
|
||||
|
||||
// @has 'normalize_assoc_item/constant.A.html' '//pre[@class="rust const"]' "pub const A: &isize"
|
||||
pub const A: <usize as Lifetimes<'static>>::Y = &0;
|
||||
|
||||
// test cross-crate re-exports
|
||||
extern crate inner;
|
||||
// @has 'normalize_assoc_item/fn.foo.html' '//pre[@class="rust fn"]' "pub fn foo() -> i32"
|
||||
pub use inner::foo;
|
Loading…
Reference in New Issue