1 use crate::clean::auto_trait::AutoTraitFinder;
2 use crate::clean::blanket_impl::BlanketImplFinder;
4 inline, Clean, Crate, ExternalCrate, Generic, GenericArg, GenericArgs, ImportSource, Item,
5 ItemKind, Lifetime, Path, PathSegment, Primitive, PrimitiveType, ResolvedPath, Type,
6 TypeBinding, Visibility,
8 use crate::core::DocContext;
9 use crate::formats::item_type::ItemType;
10 use crate::visit_lib::LibEmbargoVisitor;
13 use rustc_ast::tokenstream::TokenTree;
15 use rustc_hir::def::{DefKind, Res};
16 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
17 use rustc_middle::mir::interpret::ConstValue;
18 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef};
19 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
20 use rustc_span::symbol::{kw, sym, Symbol};
21 use std::fmt::Write as _;
27 crate fn krate(cx: &mut DocContext<'_>) -> Crate {
28 let module = crate::visit_ast::RustdocVisitor::new(cx).visit();
30 for &cnum in cx.tcx.crates(()) {
31 // Analyze doc-reachability for extern items
32 LibEmbargoVisitor::new(cx).visit_lib(cnum);
35 // Clean the crate, translating the entire librustc_ast AST to one that is
36 // understood by rustdoc.
37 let mut module = module.clean(cx);
40 ItemKind::ModuleItem(ref module) => {
41 for it in &module.items {
42 // `compiler_builtins` should be masked too, but we can't apply
43 // `#[doc(masked)]` to the injected `extern crate` because it's unstable.
44 if it.is_extern_crate()
45 && (it.attrs.has_doc_flag(sym::masked)
46 || cx.tcx.is_compiler_builtins(it.def_id.krate()))
48 cx.cache.masked_crates.insert(it.def_id.krate());
55 let local_crate = ExternalCrate { crate_num: LOCAL_CRATE };
56 let primitives = local_crate.primitives(cx.tcx);
57 let keywords = local_crate.keywords(cx.tcx);
59 let m = match *module.kind {
60 ItemKind::ModuleItem(ref mut m) => m,
63 m.items.extend(primitives.iter().map(|&(def_id, prim)| {
64 Item::from_def_id_and_parts(
67 ItemKind::PrimitiveItem(prim),
71 m.items.extend(keywords.into_iter().map(|(def_id, kw)| {
72 Item::from_def_id_and_parts(def_id, Some(kw), ItemKind::KeywordItem(kw), cx)
76 Crate { module, primitives, external_traits: cx.external_traits.clone(), collapsed: false }
79 fn external_generic_args(
80 cx: &mut DocContext<'_>,
83 bindings: Vec<TypeBinding>,
84 substs: SubstsRef<'_>,
86 let mut skip_self = has_self;
87 let mut ty_kind = None;
88 let args: Vec<_> = substs
90 .filter_map(|kind| match kind.unpack() {
91 GenericArgKind::Lifetime(lt) => match lt {
92 ty::ReLateBound(_, ty::BoundRegion { kind: ty::BrAnon(_), .. }) => {
93 Some(GenericArg::Lifetime(Lifetime::elided()))
95 _ => lt.clean(cx).map(GenericArg::Lifetime),
97 GenericArgKind::Type(_) if skip_self => {
101 GenericArgKind::Type(ty) => {
102 ty_kind = Some(ty.kind());
103 Some(GenericArg::Type(ty.clean(cx)))
105 GenericArgKind::Const(ct) => Some(GenericArg::Const(Box::new(ct.clean(cx)))),
109 if cx.tcx.fn_trait_kind_from_lang_item(did).is_some() {
110 let inputs = match ty_kind.unwrap() {
111 ty::Tuple(tys) => tys.iter().map(|t| t.expect_ty().clean(cx)).collect(),
112 _ => return GenericArgs::AngleBracketed { args, bindings },
115 // FIXME(#20299) return type comes from a projection now
116 // match types[1].kind {
117 // ty::Tuple(ref v) if v.is_empty() => None, // -> ()
118 // _ => Some(types[1].clean(cx))
120 GenericArgs::Parenthesized { inputs, output }
122 GenericArgs::AngleBracketed { args, bindings }
126 pub(super) fn external_path(
127 cx: &mut DocContext<'_>,
130 bindings: Vec<TypeBinding>,
131 substs: SubstsRef<'_>,
133 let def_kind = cx.tcx.def_kind(did);
134 let name = cx.tcx.item_name(did);
136 res: Res::Def(def_kind, did),
137 segments: vec![PathSegment {
139 args: external_generic_args(cx, did, has_self, bindings, substs),
144 /// Remove the generic arguments from a path.
145 crate fn strip_path_generics(path: Path) -> Path {
149 .map(|s| PathSegment {
151 args: GenericArgs::AngleBracketed { args: vec![], bindings: vec![] },
155 Path { res: path.res, segments }
158 crate fn qpath_to_string(p: &hir::QPath<'_>) -> String {
159 let segments = match *p {
160 hir::QPath::Resolved(_, path) => &path.segments,
161 hir::QPath::TypeRelative(_, segment) => return segment.ident.to_string(),
162 hir::QPath::LangItem(lang_item, ..) => return lang_item.name().to_string(),
165 let mut s = String::new();
166 for (i, seg) in segments.iter().enumerate() {
170 if seg.ident.name != kw::PathRoot {
171 s.push_str(&seg.ident.as_str());
177 crate fn build_deref_target_impls(cx: &mut DocContext<'_>, items: &[Item], ret: &mut Vec<Item>) {
181 let target = match *item.kind {
182 ItemKind::TypedefItem(ref t, true) => &t.type_,
186 if let Some(prim) = target.primitive_type() {
187 for &did in prim.impls(tcx).iter().filter(|did| !did.is_local()) {
188 inline::build_impl(cx, None, did, None, ret);
190 } else if let ResolvedPath { did, .. } = *target {
192 inline::build_impls(cx, None, did, None, ret);
198 crate fn name_from_pat(p: &hir::Pat<'_>) -> Symbol {
200 debug!("trying to get a name from pattern: {:?}", p);
202 Symbol::intern(&match p.kind {
203 PatKind::Wild | PatKind::Struct(..) => return kw::Underscore,
204 PatKind::Binding(_, _, ident, _) => return ident.name,
205 PatKind::TupleStruct(ref p, ..) | PatKind::Path(ref p) => qpath_to_string(p),
206 PatKind::Or(pats) => {
207 pats.iter().map(|p| name_from_pat(p).to_string()).collect::<Vec<String>>().join(" | ")
209 PatKind::Tuple(elts, _) => format!(
211 elts.iter().map(|p| name_from_pat(p).to_string()).collect::<Vec<String>>().join(", ")
213 PatKind::Box(p) => return name_from_pat(&*p),
214 PatKind::Ref(p, _) => return name_from_pat(&*p),
215 PatKind::Lit(..) => {
217 "tried to get argument name from PatKind::Lit, which is silly in function arguments"
219 return Symbol::intern("()");
221 PatKind::Range(..) => return kw::Underscore,
222 PatKind::Slice(begin, ref mid, end) => {
223 let begin = begin.iter().map(|p| name_from_pat(p).to_string());
224 let mid = mid.as_ref().map(|p| format!("..{}", name_from_pat(&**p))).into_iter();
225 let end = end.iter().map(|p| name_from_pat(p).to_string());
226 format!("[{}]", begin.chain(mid).chain(end).collect::<Vec<_>>().join(", "))
231 crate fn print_const(cx: &DocContext<'_>, n: &'tcx ty::Const<'_>) -> String {
233 ty::ConstKind::Unevaluated(ty::Unevaluated { def, substs_: _, promoted }) => {
234 let mut s = if let Some(def) = def.as_local() {
235 let hir_id = cx.tcx.hir().local_def_id_to_hir_id(def.did);
236 print_const_expr(cx.tcx, cx.tcx.hir().body_owned_by(hir_id))
238 inline::print_inlined_const(cx.tcx, def.did)
240 if let Some(promoted) = promoted {
241 s.push_str(&format!("::{:?}", promoted))
246 let mut s = n.to_string();
247 // array lengths are obviously usize
248 if s.ends_with("_usize") {
249 let n = s.len() - "_usize".len();
251 if s.ends_with(": ") {
252 let n = s.len() - ": ".len();
261 crate fn print_evaluated_const(tcx: TyCtxt<'_>, def_id: DefId) -> Option<String> {
262 tcx.const_eval_poly(def_id).ok().and_then(|val| {
263 let ty = tcx.type_of(def_id);
264 match (val, ty.kind()) {
265 (_, &ty::Ref(..)) => None,
266 (ConstValue::Scalar(_), &ty::Adt(_, _)) => None,
267 (ConstValue::Scalar(_), _) => {
268 let const_ = ty::Const::from_value(tcx, val, ty);
269 Some(print_const_with_custom_print_scalar(tcx, const_))
276 fn format_integer_with_underscore_sep(num: &str) -> String {
277 let num_chars: Vec<_> = num.chars().collect();
278 let mut num_start_index = if num_chars.get(0) == Some(&'-') { 1 } else { 0 };
279 let chunk_size = match num[num_start_index..].as_bytes() {
280 [b'0', b'b' | b'x', ..] => {
281 num_start_index += 2;
284 [b'0', b'o', ..] => {
285 num_start_index += 2;
286 let remaining_chars = num_chars.len() - num_start_index;
287 if remaining_chars <= 6 {
288 // don't add underscores to Unix permissions like 0755 or 100755
289 return num.to_string();
296 num_chars[..num_start_index]
298 .chain(num_chars[num_start_index..].rchunks(chunk_size).rev().intersperse(&['_']).flatten())
302 fn print_const_with_custom_print_scalar(tcx: TyCtxt<'_>, ct: &'tcx ty::Const<'tcx>) -> String {
303 // Use a slightly different format for integer types which always shows the actual value.
304 // For all other types, fallback to the original `pretty_print_const`.
305 match (ct.val, ct.ty.kind()) {
306 (ty::ConstKind::Value(ConstValue::Scalar(int)), ty::Uint(ui)) => {
307 format!("{}{}", format_integer_with_underscore_sep(&int.to_string()), ui.name_str())
309 (ty::ConstKind::Value(ConstValue::Scalar(int)), ty::Int(i)) => {
310 let ty = tcx.lift(ct.ty).unwrap();
311 let size = tcx.layout_of(ty::ParamEnv::empty().and(ty)).unwrap().size;
312 let data = int.assert_bits(size);
313 let sign_extended_data = size.sign_extend(data) as i128;
317 format_integer_with_underscore_sep(&sign_extended_data.to_string()),
325 crate fn is_literal_expr(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> bool {
326 if let hir::Node::Expr(expr) = tcx.hir().get(hir_id) {
327 if let hir::ExprKind::Lit(_) = &expr.kind {
331 if let hir::ExprKind::Unary(hir::UnOp::Neg, expr) = &expr.kind {
332 if let hir::ExprKind::Lit(_) = &expr.kind {
341 crate fn print_const_expr(tcx: TyCtxt<'_>, body: hir::BodyId) -> String {
343 let value = &hir.body(body).value;
345 let snippet = if !value.span.from_expansion() {
346 tcx.sess.source_map().span_to_snippet(value.span).ok()
351 snippet.unwrap_or_else(|| rustc_hir_pretty::id_to_string(&hir, body.hir_id))
354 /// Given a type Path, resolve it to a Type using the TyCtxt
355 crate fn resolve_type(cx: &mut DocContext<'_>, path: Path) -> Type {
356 debug!("resolve_type({:?})", path);
359 Res::PrimTy(p) => Primitive(PrimitiveType::from(p)),
360 Res::SelfTy(..) if path.segments.len() == 1 => Generic(kw::SelfUpper),
361 Res::Def(DefKind::TyParam, _) if path.segments.len() == 1 => Generic(path.segments[0].name),
363 let did = register_res(cx, path.res);
364 ResolvedPath { path, did }
369 crate fn get_auto_trait_and_blanket_impls(
370 cx: &mut DocContext<'tcx>,
372 ) -> impl Iterator<Item = Item> {
376 .generic_activity("get_auto_trait_impls")
377 .run(|| AutoTraitFinder::new(cx).get_auto_trait_impls(item_def_id));
378 let blanket_impls = cx
381 .generic_activity("get_blanket_impls")
382 .run(|| BlanketImplFinder { cx }.get_blanket_impls(item_def_id));
383 auto_impls.into_iter().chain(blanket_impls)
386 /// If `res` has a documentation page associated, store it in the cache.
388 /// This is later used by [`href()`] to determine the HTML link for the item.
390 /// [`href()`]: crate::html::format::href
391 crate fn register_res(cx: &mut DocContext<'_>, res: Res) -> DefId {
393 debug!("register_res({:?})", res);
395 let (did, kind) = match res {
396 // Each of these have their own page.
400 (AssocTy | AssocFn | AssocConst | Variant | Fn | TyAlias | Enum | Trait | Struct
401 | Union | Mod | ForeignTy | Const | Static | Macro(..) | TraitAlias),
403 ) => (i, kind.into()),
404 // This is part of a trait definition; document the trait.
405 Res::SelfTy(Some(trait_def_id), _) => (trait_def_id, ItemType::Trait),
406 // This is an inherent impl; it doesn't have its own page.
407 Res::SelfTy(None, Some((impl_def_id, _))) => return impl_def_id,
408 Res::SelfTy(None, None)
413 | Res::NonMacroAttr(_)
414 | Res::Err => return res.def_id(),
416 TyParam | ConstParam | Ctor(..) | ExternCrate | Use | ForeignMod | AnonConst
417 | InlineConst | OpaqueTy | Field | LifetimeParam | GlobalAsm | Impl | Closure
425 inline::record_extern_fqn(cx, did, kind);
426 if let ItemType::Trait = kind {
427 inline::record_extern_trait(cx, did);
432 crate fn resolve_use_source(cx: &mut DocContext<'_>, path: Path) -> ImportSource {
434 did: if path.res.opt_def_id().is_none() { None } else { Some(register_res(cx, path.res)) },
439 crate fn enter_impl_trait<F, R>(cx: &mut DocContext<'_>, f: F) -> R
441 F: FnOnce(&mut DocContext<'_>) -> R,
443 let old_bounds = mem::take(&mut cx.impl_trait_bounds);
445 assert!(cx.impl_trait_bounds.is_empty());
446 cx.impl_trait_bounds = old_bounds;
450 /// Find the nearest parent module of a [`DefId`].
451 crate fn find_nearest_parent_module(tcx: TyCtxt<'_>, def_id: DefId) -> Option<DefId> {
452 if def_id.is_top_level_module() {
453 // The crate root has no parent. Use it as the root instead.
456 let mut current = def_id;
457 // The immediate parent might not always be a module.
458 // Find the first parent which is.
459 while let Some(parent) = tcx.parent(current) {
460 if tcx.def_kind(parent) == DefKind::Mod {
469 /// Checks for the existence of `hidden` in the attribute below if `flag` is `sym::hidden`:
476 /// This function exists because it runs on `hir::Attributes` whereas the other is a
477 /// `clean::Attributes` method.
478 crate fn has_doc_flag(attrs: ty::Attributes<'_>, flag: Symbol) -> bool {
479 attrs.iter().any(|attr| {
480 attr.has_name(sym::doc)
481 && attr.meta_item_list().map_or(false, |l| rustc_attr::list_contains_name(&l, flag))
485 /// A link to `doc.rust-lang.org` that includes the channel name. Use this instead of manual links
486 /// so that the channel is consistent.
488 /// Set by `bootstrap::Builder::doc_rust_lang_org_channel` in order to keep tests passing on beta/stable.
489 crate const DOC_RUST_LANG_ORG_CHANNEL: &str = env!("DOC_RUST_LANG_ORG_CHANNEL");
491 /// Render a sequence of macro arms in a format suitable for displaying to the user
492 /// as part of an item declaration.
493 pub(super) fn render_macro_arms<'a>(
494 matchers: impl Iterator<Item = &'a TokenTree>,
497 let mut out = String::new();
498 for matcher in matchers {
499 writeln!(out, " {} => {{ ... }}{}", render_macro_matcher(matcher), arm_delim).unwrap();
504 /// Render a macro matcher in a format suitable for displaying to the user
505 /// as part of an item declaration.
506 pub(super) fn render_macro_matcher(matcher: &TokenTree) -> String {
507 rustc_ast_pretty::pprust::tt_to_string(matcher)
510 pub(super) fn display_macro_source(
511 cx: &mut DocContext<'_>,
517 let tts: Vec<_> = def.body.inner_tokens().into_trees().collect();
518 // Extract the spans of all matchers. They represent the "interface" of the macro.
519 let matchers = tts.chunks(4).map(|arm| &arm[0]);
522 format!("macro_rules! {} {{\n{}}}", name, render_macro_arms(matchers, ";"))
524 if matchers.len() <= 1 {
526 "{}macro {}{} {{\n ...\n}}",
527 vis.to_src_with_space(cx.tcx, def_id),
529 matchers.map(render_macro_matcher).collect::<String>(),
533 "{}macro {} {{\n{}}}",
534 vis.to_src_with_space(cx.tcx, def_id),
536 render_macro_arms(matchers, ","),