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Member "rustc-1.72.1-src/src/librustdoc/core.rs" (13 Sep 2023, 20274 Bytes) of package /linux/misc/rustc-1.72.1-src.tar.xz:


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    1 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
    2 use rustc_data_structures::sync::{self, Lrc};
    3 use rustc_data_structures::unord::UnordSet;
    4 use rustc_errors::emitter::{Emitter, EmitterWriter};
    5 use rustc_errors::json::JsonEmitter;
    6 use rustc_errors::TerminalUrl;
    7 use rustc_feature::UnstableFeatures;
    8 use rustc_hir::def::Res;
    9 use rustc_hir::def_id::{DefId, DefIdMap, DefIdSet, LocalDefId};
   10 use rustc_hir::intravisit::{self, Visitor};
   11 use rustc_hir::{HirId, Path};
   12 use rustc_interface::interface;
   13 use rustc_middle::hir::nested_filter;
   14 use rustc_middle::ty::{ParamEnv, Ty, TyCtxt};
   15 use rustc_session::config::{self, CrateType, ErrorOutputType, ResolveDocLinks};
   16 use rustc_session::Session;
   17 use rustc_session::{lint, EarlyErrorHandler};
   18 use rustc_span::symbol::sym;
   19 use rustc_span::{source_map, Span};
   20 
   21 use std::cell::RefCell;
   22 use std::mem;
   23 use std::rc::Rc;
   24 use std::sync::LazyLock;
   25 
   26 use crate::clean::inline::build_external_trait;
   27 use crate::clean::{self, ItemId};
   28 use crate::config::{Options as RustdocOptions, OutputFormat, RenderOptions};
   29 use crate::formats::cache::Cache;
   30 use crate::passes::{self, Condition::*};
   31 
   32 pub(crate) use rustc_session::config::{Input, Options, UnstableOptions};
   33 
   34 pub(crate) struct DocContext<'tcx> {
   35     pub(crate) tcx: TyCtxt<'tcx>,
   36     /// Used for normalization.
   37     ///
   38     /// Most of this logic is copied from rustc_lint::late.
   39     pub(crate) param_env: ParamEnv<'tcx>,
   40     /// Later on moved through `clean::Crate` into `cache`
   41     pub(crate) external_traits: Rc<RefCell<FxHashMap<DefId, clean::Trait>>>,
   42     /// Used while populating `external_traits` to ensure we don't process the same trait twice at
   43     /// the same time.
   44     pub(crate) active_extern_traits: DefIdSet,
   45     // The current set of parameter substitutions,
   46     // for expanding type aliases at the HIR level:
   47     /// Table `DefId` of type, lifetime, or const parameter -> substituted type, lifetime, or const
   48     pub(crate) substs: DefIdMap<clean::SubstParam>,
   49     pub(crate) current_type_aliases: DefIdMap<usize>,
   50     /// Table synthetic type parameter for `impl Trait` in argument position -> bounds
   51     pub(crate) impl_trait_bounds: FxHashMap<ImplTraitParam, Vec<clean::GenericBound>>,
   52     /// Auto-trait or blanket impls processed so far, as `(self_ty, trait_def_id)`.
   53     // FIXME(eddyb) make this a `ty::TraitRef<'tcx>` set.
   54     pub(crate) generated_synthetics: FxHashSet<(Ty<'tcx>, DefId)>,
   55     pub(crate) auto_traits: Vec<DefId>,
   56     /// The options given to rustdoc that could be relevant to a pass.
   57     pub(crate) render_options: RenderOptions,
   58     /// This same cache is used throughout rustdoc, including in [`crate::html::render`].
   59     pub(crate) cache: Cache,
   60     /// Used by [`clean::inline`] to tell if an item has already been inlined.
   61     pub(crate) inlined: FxHashSet<ItemId>,
   62     /// Used by `calculate_doc_coverage`.
   63     pub(crate) output_format: OutputFormat,
   64     /// Used by `strip_private`.
   65     pub(crate) show_coverage: bool,
   66 }
   67 
   68 impl<'tcx> DocContext<'tcx> {
   69     pub(crate) fn sess(&self) -> &'tcx Session {
   70         self.tcx.sess
   71     }
   72 
   73     pub(crate) fn with_param_env<T, F: FnOnce(&mut Self) -> T>(
   74         &mut self,
   75         def_id: DefId,
   76         f: F,
   77     ) -> T {
   78         let old_param_env = mem::replace(&mut self.param_env, self.tcx.param_env(def_id));
   79         let ret = f(self);
   80         self.param_env = old_param_env;
   81         ret
   82     }
   83 
   84     /// Call the closure with the given parameters set as
   85     /// the substitutions for a type alias' RHS.
   86     pub(crate) fn enter_alias<F, R>(
   87         &mut self,
   88         substs: DefIdMap<clean::SubstParam>,
   89         def_id: DefId,
   90         f: F,
   91     ) -> R
   92     where
   93         F: FnOnce(&mut Self) -> R,
   94     {
   95         let old_substs = mem::replace(&mut self.substs, substs);
   96         *self.current_type_aliases.entry(def_id).or_insert(0) += 1;
   97         let r = f(self);
   98         self.substs = old_substs;
   99         if let Some(count) = self.current_type_aliases.get_mut(&def_id) {
  100             *count -= 1;
  101             if *count == 0 {
  102                 self.current_type_aliases.remove(&def_id);
  103             }
  104         }
  105         r
  106     }
  107 
  108     /// Like `hir().local_def_id_to_hir_id()`, but skips calling it on fake DefIds.
  109     /// (This avoids a slice-index-out-of-bounds panic.)
  110     pub(crate) fn as_local_hir_id(tcx: TyCtxt<'_>, item_id: ItemId) -> Option<HirId> {
  111         match item_id {
  112             ItemId::DefId(real_id) => {
  113                 real_id.as_local().map(|def_id| tcx.hir().local_def_id_to_hir_id(def_id))
  114             }
  115             // FIXME: Can this be `Some` for `Auto` or `Blanket`?
  116             _ => None,
  117         }
  118     }
  119 }
  120 
  121 /// Creates a new diagnostic `Handler` that can be used to emit warnings and errors.
  122 ///
  123 /// If the given `error_format` is `ErrorOutputType::Json` and no `SourceMap` is given, a new one
  124 /// will be created for the handler.
  125 pub(crate) fn new_handler(
  126     error_format: ErrorOutputType,
  127     source_map: Option<Lrc<source_map::SourceMap>>,
  128     diagnostic_width: Option<usize>,
  129     unstable_opts: &UnstableOptions,
  130 ) -> rustc_errors::Handler {
  131     let fallback_bundle = rustc_errors::fallback_fluent_bundle(
  132         rustc_driver::DEFAULT_LOCALE_RESOURCES.to_vec(),
  133         false,
  134     );
  135     let emitter: Box<dyn Emitter + sync::Send> = match error_format {
  136         ErrorOutputType::HumanReadable(kind) => {
  137             let (short, color_config) = kind.unzip();
  138             Box::new(
  139                 EmitterWriter::stderr(
  140                     color_config,
  141                     source_map.map(|sm| sm as _),
  142                     None,
  143                     fallback_bundle,
  144                     short,
  145                     unstable_opts.teach,
  146                     diagnostic_width,
  147                     false,
  148                     unstable_opts.track_diagnostics,
  149                     TerminalUrl::No,
  150                 )
  151                 .ui_testing(unstable_opts.ui_testing),
  152             )
  153         }
  154         ErrorOutputType::Json { pretty, json_rendered } => {
  155             let source_map = source_map.unwrap_or_else(|| {
  156                 Lrc::new(source_map::SourceMap::new(source_map::FilePathMapping::empty()))
  157             });
  158             Box::new(
  159                 JsonEmitter::stderr(
  160                     None,
  161                     source_map,
  162                     None,
  163                     fallback_bundle,
  164                     pretty,
  165                     json_rendered,
  166                     diagnostic_width,
  167                     false,
  168                     unstable_opts.track_diagnostics,
  169                     TerminalUrl::No,
  170                 )
  171                 .ui_testing(unstable_opts.ui_testing),
  172             )
  173         }
  174     };
  175 
  176     rustc_errors::Handler::with_emitter_and_flags(
  177         emitter,
  178         unstable_opts.diagnostic_handler_flags(true),
  179     )
  180 }
  181 
  182 /// Parse, resolve, and typecheck the given crate.
  183 pub(crate) fn create_config(
  184     handler: &EarlyErrorHandler,
  185     RustdocOptions {
  186         input,
  187         crate_name,
  188         proc_macro_crate,
  189         error_format,
  190         diagnostic_width,
  191         libs,
  192         externs,
  193         mut cfgs,
  194         check_cfgs,
  195         codegen_options,
  196         unstable_opts,
  197         target,
  198         edition,
  199         maybe_sysroot,
  200         lint_opts,
  201         describe_lints,
  202         lint_cap,
  203         scrape_examples_options,
  204         ..
  205     }: RustdocOptions,
  206     RenderOptions { document_private, .. }: &RenderOptions,
  207 ) -> rustc_interface::Config {
  208     // Add the doc cfg into the doc build.
  209     cfgs.push("doc".to_string());
  210 
  211     let input = Input::File(input);
  212 
  213     // By default, rustdoc ignores all lints.
  214     // Specifically unblock lints relevant to documentation or the lint machinery itself.
  215     let mut lints_to_show = vec![
  216         // it's unclear whether these should be part of rustdoc directly (#77364)
  217         rustc_lint::builtin::MISSING_DOCS.name.to_string(),
  218         rustc_lint::builtin::INVALID_DOC_ATTRIBUTES.name.to_string(),
  219         // these are definitely not part of rustdoc, but we want to warn on them anyway.
  220         rustc_lint::builtin::RENAMED_AND_REMOVED_LINTS.name.to_string(),
  221         rustc_lint::builtin::UNKNOWN_LINTS.name.to_string(),
  222         rustc_lint::builtin::UNEXPECTED_CFGS.name.to_string(),
  223         // this lint is needed to support `#[expect]` attributes
  224         rustc_lint::builtin::UNFULFILLED_LINT_EXPECTATIONS.name.to_string(),
  225     ];
  226     lints_to_show.extend(crate::lint::RUSTDOC_LINTS.iter().map(|lint| lint.name.to_string()));
  227 
  228     let (lint_opts, lint_caps) = crate::lint::init_lints(lints_to_show, lint_opts, |lint| {
  229         Some((lint.name_lower(), lint::Allow))
  230     });
  231 
  232     let crate_types =
  233         if proc_macro_crate { vec![CrateType::ProcMacro] } else { vec![CrateType::Rlib] };
  234     let resolve_doc_links =
  235         if *document_private { ResolveDocLinks::All } else { ResolveDocLinks::Exported };
  236     let test = scrape_examples_options.map(|opts| opts.scrape_tests).unwrap_or(false);
  237     // plays with error output here!
  238     let sessopts = config::Options {
  239         maybe_sysroot,
  240         search_paths: libs,
  241         crate_types,
  242         lint_opts,
  243         lint_cap,
  244         cg: codegen_options,
  245         externs,
  246         target_triple: target,
  247         unstable_features: UnstableFeatures::from_environment(crate_name.as_deref()),
  248         actually_rustdoc: true,
  249         resolve_doc_links,
  250         unstable_opts,
  251         error_format,
  252         diagnostic_width,
  253         edition,
  254         describe_lints,
  255         crate_name,
  256         test,
  257         ..Options::default()
  258     };
  259 
  260     interface::Config {
  261         opts: sessopts,
  262         crate_cfg: interface::parse_cfgspecs(handler, cfgs),
  263         crate_check_cfg: interface::parse_check_cfg(handler, check_cfgs),
  264         input,
  265         output_file: None,
  266         output_dir: None,
  267         file_loader: None,
  268         locale_resources: rustc_driver::DEFAULT_LOCALE_RESOURCES,
  269         lint_caps,
  270         parse_sess_created: None,
  271         register_lints: Some(Box::new(crate::lint::register_lints)),
  272         override_queries: Some(|_sess, providers, _external_providers| {
  273             // Most lints will require typechecking, so just don't run them.
  274             providers.lint_mod = |_, _| {};
  275             // hack so that `used_trait_imports` won't try to call typeck
  276             providers.used_trait_imports = |_, _| {
  277                 static EMPTY_SET: LazyLock<UnordSet<LocalDefId>> = LazyLock::new(UnordSet::default);
  278                 &EMPTY_SET
  279             };
  280             // In case typeck does end up being called, don't ICE in case there were name resolution errors
  281             providers.typeck = move |tcx, def_id| {
  282                 // Closures' tables come from their outermost function,
  283                 // as they are part of the same "inference environment".
  284                 // This avoids emitting errors for the parent twice (see similar code in `typeck_with_fallback`)
  285                 let typeck_root_def_id = tcx.typeck_root_def_id(def_id.to_def_id()).expect_local();
  286                 if typeck_root_def_id != def_id {
  287                     return tcx.typeck(typeck_root_def_id);
  288                 }
  289 
  290                 let hir = tcx.hir();
  291                 let body = hir.body(hir.body_owned_by(def_id));
  292                 debug!("visiting body for {:?}", def_id);
  293                 EmitIgnoredResolutionErrors::new(tcx).visit_body(body);
  294                 (rustc_interface::DEFAULT_QUERY_PROVIDERS.typeck)(tcx, def_id)
  295             };
  296         }),
  297         make_codegen_backend: None,
  298         registry: rustc_driver::diagnostics_registry(),
  299     }
  300 }
  301 
  302 pub(crate) fn run_global_ctxt(
  303     tcx: TyCtxt<'_>,
  304     show_coverage: bool,
  305     render_options: RenderOptions,
  306     output_format: OutputFormat,
  307 ) -> (clean::Crate, RenderOptions, Cache) {
  308     // Certain queries assume that some checks were run elsewhere
  309     // (see https://github.com/rust-lang/rust/pull/73566#issuecomment-656954425),
  310     // so type-check everything other than function bodies in this crate before running lints.
  311 
  312     // NOTE: this does not call `tcx.analysis()` so that we won't
  313     // typeck function bodies or run the default rustc lints.
  314     // (see `override_queries` in the `config`)
  315 
  316     // HACK(jynelson) this calls an _extremely_ limited subset of `typeck`
  317     // and might break if queries change their assumptions in the future.
  318     tcx.sess.time("type_collecting", || {
  319         tcx.hir().for_each_module(|module| tcx.ensure().collect_mod_item_types(module))
  320     });
  321 
  322     // NOTE: This is copy/pasted from typeck/lib.rs and should be kept in sync with those changes.
  323     tcx.sess.time("item_types_checking", || {
  324         tcx.hir().for_each_module(|module| tcx.ensure().check_mod_item_types(module))
  325     });
  326     tcx.sess.abort_if_errors();
  327     tcx.sess.time("missing_docs", || {
  328         rustc_lint::check_crate(tcx, rustc_lint::builtin::MissingDoc::new);
  329     });
  330     tcx.sess.time("check_mod_attrs", || {
  331         tcx.hir().for_each_module(|module| tcx.ensure().check_mod_attrs(module))
  332     });
  333     rustc_passes::stability::check_unused_or_stable_features(tcx);
  334 
  335     let auto_traits =
  336         tcx.all_traits().filter(|&trait_def_id| tcx.trait_is_auto(trait_def_id)).collect();
  337 
  338     let mut ctxt = DocContext {
  339         tcx,
  340         param_env: ParamEnv::empty(),
  341         external_traits: Default::default(),
  342         active_extern_traits: Default::default(),
  343         substs: Default::default(),
  344         current_type_aliases: Default::default(),
  345         impl_trait_bounds: Default::default(),
  346         generated_synthetics: Default::default(),
  347         auto_traits,
  348         cache: Cache::new(render_options.document_private),
  349         inlined: FxHashSet::default(),
  350         output_format,
  351         render_options,
  352         show_coverage,
  353     };
  354 
  355     for cnum in tcx.crates(()) {
  356         crate::visit_lib::lib_embargo_visit_item(&mut ctxt, cnum.as_def_id());
  357     }
  358 
  359     // Small hack to force the Sized trait to be present.
  360     //
  361     // Note that in case of `#![no_core]`, the trait is not available.
  362     if let Some(sized_trait_did) = ctxt.tcx.lang_items().sized_trait() {
  363         let sized_trait = build_external_trait(&mut ctxt, sized_trait_did);
  364         ctxt.external_traits.borrow_mut().insert(sized_trait_did, sized_trait);
  365     }
  366 
  367     debug!("crate: {:?}", tcx.hir().krate());
  368 
  369     let mut krate = tcx.sess.time("clean_crate", || clean::krate(&mut ctxt));
  370 
  371     if krate.module.doc_value().is_empty() {
  372         let help = format!(
  373             "The following guide may be of use:\n\
  374             {}/rustdoc/how-to-write-documentation.html",
  375             crate::DOC_RUST_LANG_ORG_CHANNEL
  376         );
  377         tcx.struct_lint_node(
  378             crate::lint::MISSING_CRATE_LEVEL_DOCS,
  379             DocContext::as_local_hir_id(tcx, krate.module.item_id).unwrap(),
  380             "no documentation found for this crate's top-level module",
  381             |lint| lint.help(help),
  382         );
  383     }
  384 
  385     fn report_deprecated_attr(name: &str, diag: &rustc_errors::Handler, sp: Span) {
  386         let mut msg =
  387             diag.struct_span_warn(sp, format!("the `#![doc({})]` attribute is deprecated", name));
  388         msg.note(
  389             "see issue #44136 <https://github.com/rust-lang/rust/issues/44136> \
  390             for more information",
  391         );
  392 
  393         if name == "no_default_passes" {
  394             msg.help("`#![doc(no_default_passes)]` no longer functions; you may want to use `#![doc(document_private_items)]`");
  395         } else if name.starts_with("passes") {
  396             msg.help("`#![doc(passes = \"...\")]` no longer functions; you may want to use `#![doc(document_private_items)]`");
  397         } else if name.starts_with("plugins") {
  398             msg.warn("`#![doc(plugins = \"...\")]` no longer functions; see CVE-2018-1000622 <https://nvd.nist.gov/vuln/detail/CVE-2018-1000622>");
  399         }
  400 
  401         msg.emit();
  402     }
  403 
  404     // Process all of the crate attributes, extracting plugin metadata along
  405     // with the passes which we are supposed to run.
  406     for attr in krate.module.attrs.lists(sym::doc) {
  407         let diag = ctxt.sess().diagnostic();
  408 
  409         let name = attr.name_or_empty();
  410         // `plugins = "..."`, `no_default_passes`, and `passes = "..."` have no effect
  411         if attr.is_word() && name == sym::no_default_passes {
  412             report_deprecated_attr("no_default_passes", diag, attr.span());
  413         } else if attr.value_str().is_some() {
  414             match name {
  415                 sym::passes => {
  416                     report_deprecated_attr("passes = \"...\"", diag, attr.span());
  417                 }
  418                 sym::plugins => {
  419                     report_deprecated_attr("plugins = \"...\"", diag, attr.span());
  420                 }
  421                 _ => (),
  422             }
  423         }
  424 
  425         if attr.is_word() && name == sym::document_private_items {
  426             ctxt.render_options.document_private = true;
  427         }
  428     }
  429 
  430     info!("Executing passes");
  431 
  432     for p in passes::defaults(show_coverage) {
  433         let run = match p.condition {
  434             Always => true,
  435             WhenDocumentPrivate => ctxt.render_options.document_private,
  436             WhenNotDocumentPrivate => !ctxt.render_options.document_private,
  437             WhenNotDocumentHidden => !ctxt.render_options.document_hidden,
  438         };
  439         if run {
  440             debug!("running pass {}", p.pass.name);
  441             krate = tcx.sess.time(p.pass.name, || (p.pass.run)(krate, &mut ctxt));
  442         }
  443     }
  444 
  445     tcx.sess.time("check_lint_expectations", || tcx.check_expectations(Some(sym::rustdoc)));
  446 
  447     if tcx.sess.diagnostic().has_errors_or_lint_errors().is_some() {
  448         rustc_errors::FatalError.raise();
  449     }
  450 
  451     krate = tcx.sess.time("create_format_cache", || Cache::populate(&mut ctxt, krate));
  452 
  453     (krate, ctxt.render_options, ctxt.cache)
  454 }
  455 
  456 /// Due to <https://github.com/rust-lang/rust/pull/73566>,
  457 /// the name resolution pass may find errors that are never emitted.
  458 /// If typeck is called after this happens, then we'll get an ICE:
  459 /// 'Res::Error found but not reported'. To avoid this, emit the errors now.
  460 struct EmitIgnoredResolutionErrors<'tcx> {
  461     tcx: TyCtxt<'tcx>,
  462 }
  463 
  464 impl<'tcx> EmitIgnoredResolutionErrors<'tcx> {
  465     fn new(tcx: TyCtxt<'tcx>) -> Self {
  466         Self { tcx }
  467     }
  468 }
  469 
  470 impl<'tcx> Visitor<'tcx> for EmitIgnoredResolutionErrors<'tcx> {
  471     type NestedFilter = nested_filter::OnlyBodies;
  472 
  473     fn nested_visit_map(&mut self) -> Self::Map {
  474         // We need to recurse into nested closures,
  475         // since those will fallback to the parent for type checking.
  476         self.tcx.hir()
  477     }
  478 
  479     fn visit_path(&mut self, path: &Path<'tcx>, _id: HirId) {
  480         debug!("visiting path {:?}", path);
  481         if path.res == Res::Err {
  482             // We have less context here than in rustc_resolve,
  483             // so we can only emit the name and span.
  484             // However we can give a hint that rustc_resolve will have more info.
  485             let label = format!(
  486                 "could not resolve path `{}`",
  487                 path.segments
  488                     .iter()
  489                     .map(|segment| segment.ident.as_str())
  490                     .intersperse("::")
  491                     .collect::<String>()
  492             );
  493             let mut err = rustc_errors::struct_span_err!(
  494                 self.tcx.sess,
  495                 path.span,
  496                 E0433,
  497                 "failed to resolve: {}",
  498                 label
  499             );
  500             err.span_label(path.span, label);
  501             err.note("this error was originally ignored because you are running `rustdoc`");
  502             err.note("try running again with `rustc` or `cargo check` and you may get a more detailed error");
  503             err.emit();
  504         }
  505         // We could have an outer resolution that succeeded,
  506         // but with generic parameters that failed.
  507         // Recurse into the segments so we catch those too.
  508         intravisit::walk_path(self, path);
  509     }
  510 }
  511 
  512 /// `DefId` or parameter index (`ty::ParamTy.index`) of a synthetic type parameter
  513 /// for `impl Trait` in argument position.
  514 #[derive(Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord)]
  515 pub(crate) enum ImplTraitParam {
  516     DefId(DefId),
  517     ParamIndex(u32),
  518 }
  519 
  520 impl From<DefId> for ImplTraitParam {
  521     fn from(did: DefId) -> Self {
  522         ImplTraitParam::DefId(did)
  523     }
  524 }
  525 
  526 impl From<u32> for ImplTraitParam {
  527     fn from(idx: u32) -> Self {
  528         ImplTraitParam::ParamIndex(idx)
  529     }
  530 }