diff options
Diffstat (limited to 'src/librustdoc/html/render/context.rs')
| -rw-r--r-- | src/librustdoc/html/render/context.rs | 53 |
1 files changed, 51 insertions, 2 deletions
diff --git a/src/librustdoc/html/render/context.rs b/src/librustdoc/html/render/context.rs index bb1c186668c..0bc10c5e10f 100644 --- a/src/librustdoc/html/render/context.rs +++ b/src/librustdoc/html/render/context.rs @@ -7,8 +7,10 @@ use std::sync::mpsc::{channel, Receiver}; use rustc_data_structures::fx::{FxHashMap, FxHashSet}; use rustc_hir::def_id::{DefIdMap, LOCAL_CRATE}; +use rustc_middle::ty::fast_reject::{DeepRejectCtxt, TreatParams}; use rustc_middle::ty::TyCtxt; use rustc_session::Session; +use rustc_span::def_id::DefId; use rustc_span::edition::Edition; use rustc_span::source_map::FileName; use rustc_span::{sym, Symbol}; @@ -22,13 +24,13 @@ use super::{ sidebar::{sidebar_module_like, Sidebar}, AllTypes, LinkFromSrc, StylePath, }; -use crate::clean::{self, types::ExternalLocation, ExternalCrate}; +use crate::clean::{self, types::ExternalLocation, ExternalCrate, TypeAliasItem}; use crate::config::{ModuleSorting, RenderOptions}; use crate::docfs::{DocFS, PathError}; use crate::error::Error; use crate::formats::cache::Cache; use crate::formats::item_type::ItemType; -use crate::formats::FormatRenderer; +use crate::formats::{self, FormatRenderer}; use crate::html::escape::Escape; use crate::html::format::{join_with_double_colon, Buffer}; use crate::html::markdown::{self, plain_text_summary, ErrorCodes, IdMap}; @@ -147,6 +149,53 @@ impl SharedContext<'_> { pub(crate) fn edition(&self) -> Edition { self.tcx.sess.edition() } + + /// Returns a list of impls on the given type, and, if it's a type alias, + /// other types that it aliases. + pub(crate) fn all_impls_for_item<'a>( + &'a self, + it: &clean::Item, + did: DefId, + ) -> Vec<&'a formats::Impl> { + let tcx = self.tcx; + let cache = &self.cache; + let mut saw_impls = FxHashSet::default(); + let mut v: Vec<&formats::Impl> = cache + .impls + .get(&did) + .map(Vec::as_slice) + .unwrap_or(&[]) + .iter() + .filter(|i| saw_impls.insert(i.def_id())) + .collect(); + if let TypeAliasItem(ait) = &*it.kind && + let aliased_clean_type = ait.item_type.as_ref().unwrap_or(&ait.type_) && + let Some(aliased_type_defid) = aliased_clean_type.def_id(cache) && + let Some(av) = cache.impls.get(&aliased_type_defid) && + let Some(alias_def_id) = it.item_id.as_def_id() + { + // This branch of the compiler compares types structually, but does + // not check trait bounds. That's probably fine, since type aliases + // don't normally constrain on them anyway. + // https://github.com/rust-lang/rust/issues/21903 + // + // FIXME(lazy_type_alias): Once the feature is complete or stable, rewrite this to use type unification. + // Be aware of `tests/rustdoc/issue-112515-impl-ty-alias.rs` which might regress. + let aliased_ty = tcx.type_of(alias_def_id).skip_binder(); + let reject_cx = DeepRejectCtxt { + treat_obligation_params: TreatParams::AsCandidateKey, + }; + v.extend(av.iter().filter(|impl_| { + if let Some(impl_def_id) = impl_.impl_item.item_id.as_def_id() { + reject_cx.types_may_unify(aliased_ty, tcx.type_of(impl_def_id).skip_binder()) + && saw_impls.insert(impl_def_id) + } else { + false + } + })); + } + v + } } impl<'tcx> Context<'tcx> { |