Restructure add_item_to_search_index to eliminate code paths

Many of the code paths it handled were actually impossible. In other
cases, the various checks and transformations were spread around in such
a way that it was hard to tell what was going on.
This commit is contained in:
Noah Lev 2024-08-02 14:48:36 -07:00
parent 08f4d54ea9
commit 220c2d8c9b

View File

@ -442,7 +442,9 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
}
fn add_item_to_search_index(tcx: TyCtxt<'_>, cache: &mut Cache, item: &clean::Item, name: Symbol) {
let ((parent_did, parent_path), is_impl_child) = match *item.kind {
// Item has a name, so it must also have a DefId (can't be an impl, let alone a blanket or auto impl).
let item_def_id = item.item_id.as_def_id().unwrap();
let (parent_did, parent_path) = match *item.kind {
clean::StrippedItem(..) => return,
clean::AssocConstItem(..) | clean::AssocTypeItem(..)
if cache.parent_stack.last().is_some_and(|parent| parent.is_trait_impl()) =>
@ -454,123 +456,114 @@ fn add_item_to_search_index(tcx: TyCtxt<'_>, cache: &mut Cache, item: &clean::It
| clean::TyAssocConstItem(..)
| clean::TyAssocTypeItem(..)
| clean::StructFieldItem(..)
| clean::VariantItem(..) => (
(
Some(
cache
.parent_stack
.last()
.expect("parent_stack is empty")
.item_id()
.expect_def_id(),
),
Some(&cache.stack[..cache.stack.len() - 1]),
),
false,
),
| clean::VariantItem(..) => {
// Don't index if containing module is stripped (i.e., private),
// or if item is tuple struct/variant field (name is a number -> not useful for search).
if cache.stripped_mod
|| item.type_() == ItemType::StructField
&& name.as_str().chars().all(|c| c.is_digit(10))
{
return;
}
let parent_did =
cache.parent_stack.last().expect("parent_stack is empty").item_id().expect_def_id();
let parent_path = &cache.stack[..cache.stack.len() - 1];
(Some(parent_did), parent_path)
}
clean::MethodItem(..) | clean::AssocConstItem(..) | clean::AssocTypeItem(..) => {
let last = cache.parent_stack.last().expect("parent_stack is empty 2");
let did = match &*last {
ParentStackItem::Impl {
// impl Trait for &T { fn method(self); }
//
// When generating a function index with the above shape, we want it
// associated with `T`, not with the primitive reference type. It should
// show up as `T::method`, rather than `reference::method`, in the search
// results page.
for_: clean::Type::BorrowedRef { type_, .. },
..
} => type_.def_id(&cache),
let parent_did = match &*last {
// impl Trait for &T { fn method(self); }
//
// When generating a function index with the above shape, we want it
// associated with `T`, not with the primitive reference type. It should
// show up as `T::method`, rather than `reference::method`, in the search
// results page.
ParentStackItem::Impl { for_: clean::Type::BorrowedRef { type_, .. }, .. } => {
type_.def_id(&cache)
}
ParentStackItem::Impl { for_, .. } => for_.def_id(&cache),
ParentStackItem::Type(item_id) => item_id.as_def_id(),
};
let path = did
.and_then(|did| cache.paths.get(&did))
// The current stack not necessarily has correlation
// for where the type was defined. On the other
// hand, `paths` always has the right
// information if present.
.map(|(fqp, _)| &fqp[..fqp.len() - 1]);
((did, path), true)
let Some(parent_did) = parent_did else { return };
// The current stack not necessarily has correlation
// for where the type was defined. On the other
// hand, `paths` always has the right
// information if present.
match cache.paths.get(&parent_did) {
Some((fqp, _)) => (Some(parent_did), &fqp[..fqp.len() - 1]),
None => {
handle_orphan_impl_child(cache, item, parent_did);
return;
}
}
}
_ => {
// Don't index if item is crate root, which is inserted later on when serializing the index.
if item_def_id.is_crate_root() {
return;
}
(None, &*cache.stack)
}
_ => ((None, Some(&*cache.stack)), false),
};
if let Some(parent_did) = parent_did
&& parent_path.is_none()
&& is_impl_child
{
// We have a parent, but we don't know where they're
// defined yet. Wait for later to index this item.
let impl_generics = clean_impl_generics(cache.parent_stack.last());
let impl_id = if let Some(ParentStackItem::Impl { item_id, .. }) = cache.parent_stack.last()
{
item_id.as_def_id()
} else {
None
};
let orphan_item =
OrphanImplItem { parent: parent_did, item: item.clone(), impl_generics, impl_id };
cache.orphan_impl_items.push(orphan_item);
} else if let Some(path) = parent_path
&& (is_impl_child || !cache.stripped_mod)
{
debug_assert!(!item.is_stripped());
debug_assert!(!item.is_stripped());
// A crate has a module at its root, containing all items,
// which should not be indexed. The crate-item itself is
// inserted later on when serializing the search-index.
if item.item_id.as_def_id().is_some_and(|idx| !idx.is_crate_root())
&& let ty = item.type_()
&& (ty != ItemType::StructField || u16::from_str_radix(name.as_str(), 10).is_err())
{
let desc = short_markdown_summary(&item.doc_value(), &item.link_names(cache));
// For searching purposes, a re-export is a duplicate if:
//
// - It's either an inline, or a true re-export
// - It's got the same name
// - Both of them have the same exact path
let defid = (match &*item.kind {
&clean::ItemKind::ImportItem(ref import) => import.source.did,
_ => None,
})
.or_else(|| item.item_id.as_def_id());
// In case this is a field from a tuple struct, we don't add it into
// the search index because its name is something like "0", which is
// not useful for rustdoc search.
let path = join_with_double_colon(path);
let impl_id =
if let Some(ParentStackItem::Impl { item_id, .. }) = cache.parent_stack.last() {
item_id.as_def_id()
} else {
None
};
let search_type = get_function_type_for_search(
&item,
tcx,
clean_impl_generics(cache.parent_stack.last()).as_ref(),
parent_did,
cache,
);
let aliases = item.attrs.get_doc_aliases();
let deprecation = item.deprecation(tcx);
let index_item = IndexItem {
ty,
defid,
name,
path,
desc,
parent: parent_did,
parent_idx: None,
exact_path: None,
impl_id,
search_type,
aliases,
deprecation,
};
cache.search_index.push(index_item);
}
}
let desc = short_markdown_summary(&item.doc_value(), &item.link_names(cache));
// For searching purposes, a re-export is a duplicate if:
//
// - It's either an inline, or a true re-export
// - It's got the same name
// - Both of them have the same exact path
let defid = match &*item.kind {
clean::ItemKind::ImportItem(import) => import.source.did.unwrap_or(item_def_id),
_ => item_def_id,
};
let path = join_with_double_colon(parent_path);
let impl_id = if let Some(ParentStackItem::Impl { item_id, .. }) = cache.parent_stack.last() {
item_id.as_def_id()
} else {
None
};
let search_type = get_function_type_for_search(
&item,
tcx,
clean_impl_generics(cache.parent_stack.last()).as_ref(),
parent_did,
cache,
);
let aliases = item.attrs.get_doc_aliases();
let deprecation = item.deprecation(tcx);
let index_item = IndexItem {
ty: item.type_(),
defid: Some(defid),
name,
path,
desc,
parent: parent_did,
parent_idx: None,
exact_path: None,
impl_id,
search_type,
aliases,
deprecation,
};
cache.search_index.push(index_item);
}
/// We have a parent, but we don't know where they're
/// defined yet. Wait for later to index this item.
/// See [`Cache::orphan_impl_items`].
fn handle_orphan_impl_child(cache: &mut Cache, item: &clean::Item, parent_did: DefId) {
let impl_generics = clean_impl_generics(cache.parent_stack.last());
let impl_id = if let Some(ParentStackItem::Impl { item_id, .. }) = cache.parent_stack.last() {
item_id.as_def_id()
} else {
None
};
let orphan_item =
OrphanImplItem { parent: parent_did, item: item.clone(), impl_generics, impl_id };
cache.orphan_impl_items.push(orphan_item);
}
pub(crate) struct OrphanImplItem {