src/librustc_save_analysis/dump_visitor.rs

   1 //! Write the output of rustc's analysis to an implementor of Dump.
   2 //!
   3 //! Dumping the analysis is implemented by walking the AST and getting a bunch of
   4 //! info out from all over the place. We use `DefId`s to identify objects. The
   5 //! tricky part is getting syntactic (span, source text) and semantic (reference
   6 //! `DefId`s) information for parts of expressions which the compiler has discarded.
   7 //! E.g., in a path `foo::bar::baz`, the compiler only keeps a span for the whole
   8 //! path and a reference to `baz`, but we want spans and references for all three
   9 //! idents.
  10 //!
  11 //! SpanUtils is used to manipulate spans. In particular, to extract sub-spans
  12 //! from spans (e.g., the span for `bar` from the above example path).
  13 //! DumpVisitor walks the AST and processes it, and Dumper is used for
  14 //! recording the output.
  15
  16 use rustc_ast::ast::{self};
  17 use rustc_ast::{token, walk_list};
  18 use rustc_data_structures::fx::FxHashSet;
  19 use rustc_hir as hir;
  20 use rustc_hir::def::{DefKind as HirDefKind, Res};
  21 use rustc_hir::def_id::{DefId, LocalDefId};
  22 use rustc_hir::intravisit::{self, Visitor};
  23 use rustc_hir_pretty::{bounds_to_string, fn_to_string, generic_params_to_string, ty_to_string};
  24 use rustc_middle::hir::map::Map;
  25 use rustc_middle::span_bug;
  26 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
  27 use rustc_session::config::Input;
  28 use rustc_span::source_map::respan;
  29 use rustc_span::symbol::Ident;
  30 use rustc_span::*;
  31
  32 use std::env;
  33 use std::path::Path;
  34
  35 use crate::dumper::{Access, Dumper};
  36 use crate::sig;
  37 use crate::span_utils::SpanUtils;
  38 use crate::{
  39     escape, generated_code, id_from_def_id, id_from_hir_id, lower_attributes, PathCollector,
  40     SaveContext,
  41 };
  42
  43 use rls_data::{
  44     CompilationOptions, CratePreludeData, Def, DefKind, GlobalCrateId, Import, ImportKind, Ref,
  45     RefKind, Relation, RelationKind, SpanData,
  46 };
  47
  48 use tracing::{debug, error};
  49
  50 macro_rules! down_cast_data {
  51     ($id:ident, $kind:ident, $sp:expr) => {
  52         let $id = if let super::Data::$kind(data) = $id {
  53             data
  54         } else {
  55             span_bug!($sp, "unexpected data kind: {:?}", $id);
  56         };
  57     };
  58 }
  59
  60 macro_rules! access_from {
  61     ($save_ctxt:expr, $item:expr, $id:expr) => {
  62         Access {
  63             public: $item.vis.node.is_pub(),
  64             reachable: $save_ctxt.access_levels.is_reachable($id),
  65         }
  66     };
  67 }
  68
  69 macro_rules! access_from_vis {
  70     ($save_ctxt:expr, $vis:expr, $id:expr) => {
  71         Access { public: $vis.node.is_pub(), reachable: $save_ctxt.access_levels.is_reachable($id) }
  72     };
  73 }
  74
  75 pub struct DumpVisitor<'tcx> {
  76     pub save_ctxt: SaveContext<'tcx>,
  77     tcx: TyCtxt<'tcx>,
  78     dumper: Dumper,
  79
  80     span: SpanUtils<'tcx>,
  81     // Set of macro definition (callee) spans, and the set
  82     // of macro use (callsite) spans. We store these to ensure
  83     // we only write one macro def per unique macro definition, and
  84     // one macro use per unique callsite span.
  85     // mac_defs: FxHashSet<Span>,
  86     // macro_calls: FxHashSet<Span>,
  87 }
  88
  89 impl<'tcx> DumpVisitor<'tcx> {
  90     pub fn new(save_ctxt: SaveContext<'tcx>) -> DumpVisitor<'tcx> {
  91         let span_utils = SpanUtils::new(&save_ctxt.tcx.sess);
  92         let dumper = Dumper::new(save_ctxt.config.clone());
  93         DumpVisitor {
  94             tcx: save_ctxt.tcx,
  95             save_ctxt,
  96             dumper,
  97             span: span_utils,
  98             // mac_defs: FxHashSet::default(),
  99             // macro_calls: FxHashSet::default(),
 100         }
 101     }
 102
 103     pub fn analysis(&self) -> &rls_data::Analysis {
 104         self.dumper.analysis()
 105     }
 106
 107     fn nest_typeck_results<F>(&mut self, item_def_id: LocalDefId, f: F)
 108     where
 109         F: FnOnce(&mut Self),
 110     {
 111         let typeck_results = if self.tcx.has_typeck_results(item_def_id) {
 112             Some(self.tcx.typeck(item_def_id))
 113         } else {
 114             None
 115         };
 116
 117         let old_maybe_typeck_results = self.save_ctxt.maybe_typeck_results;
 118         self.save_ctxt.maybe_typeck_results = typeck_results;
 119         f(self);
 120         self.save_ctxt.maybe_typeck_results = old_maybe_typeck_results;
 121     }
 122
 123     fn span_from_span(&self, span: Span) -> SpanData {
 124         self.save_ctxt.span_from_span(span)
 125     }
 126
 127     fn lookup_def_id(&self, ref_id: hir::HirId) -> Option<DefId> {
 128         self.save_ctxt.lookup_def_id(ref_id)
 129     }
 130
 131     pub fn dump_crate_info(&mut self, name: &str, krate: &hir::Crate<'_>) {
 132         let source_file = self.tcx.sess.local_crate_source_file.as_ref();
 133         let crate_root = source_file.map(|source_file| {
 134             let source_file = Path::new(source_file);
 135             match source_file.file_name() {
 136                 Some(_) => source_file.parent().unwrap().display(),
 137                 None => source_file.display(),
 138             }
 139             .to_string()
 140         });
 141
 142         let data = CratePreludeData {
 143             crate_id: GlobalCrateId {
 144                 name: name.into(),
 145                 disambiguator: self
 146                     .tcx
 147                     .sess
 148                     .local_crate_disambiguator()
 149                     .to_fingerprint()
 150                     .as_value(),
 151             },
 152             crate_root: crate_root.unwrap_or_else(|| "<no source>".to_owned()),
 153             external_crates: self.save_ctxt.get_external_crates(),
 154             span: self.span_from_span(krate.item.span),
 155         };
 156
 157         self.dumper.crate_prelude(data);
 158     }
 159
 160     pub fn dump_compilation_options(&mut self, input: &Input, crate_name: &str) {
 161         // Apply possible `remap-path-prefix` remapping to the input source file
 162         // (and don't include remapping args anymore)
 163         let (program, arguments) = {
 164             let remap_arg_indices = {
 165                 let mut indices = FxHashSet::default();
 166                 // Args are guaranteed to be valid UTF-8 (checked early)
 167                 for (i, e) in env::args().enumerate() {
 168                     if e.starts_with("--remap-path-prefix=") {
 169                         indices.insert(i);
 170                     } else if e == "--remap-path-prefix" {
 171                         indices.insert(i);
 172                         indices.insert(i + 1);
 173                     }
 174                 }
 175                 indices
 176             };
 177
 178             let mut args = env::args()
 179                 .enumerate()
 180                 .filter(|(i, _)| !remap_arg_indices.contains(i))
 181                 .map(|(_, arg)| match input {
 182                     Input::File(ref path) if path == Path::new(&arg) => {
 183                         let mapped = &self.tcx.sess.local_crate_source_file;
 184                         mapped.as_ref().unwrap().to_string_lossy().into()
 185                     }
 186                     _ => arg,
 187                 });
 188
 189             (args.next().unwrap(), args.collect())
 190         };
 191
 192         let data = CompilationOptions {
 193             directory: self.tcx.sess.working_dir.0.clone(),
 194             program,
 195             arguments,
 196             output: self.save_ctxt.compilation_output(crate_name),
 197         };
 198
 199         self.dumper.compilation_opts(data);
 200     }
 201
 202     fn write_segments(&mut self, segments: impl IntoIterator<Item = &'tcx hir::PathSegment<'tcx>>) {
 203         for seg in segments {
 204             if let Some(data) = self.save_ctxt.get_path_segment_data(seg) {
 205                 self.dumper.dump_ref(data);
 206             }
 207         }
 208     }
 209
 210     fn write_sub_paths(&mut self, path: &'tcx hir::Path<'tcx>) {
 211         self.write_segments(path.segments)
 212     }
 213
 214     // As write_sub_paths, but does not process the last ident in the path (assuming it
 215     // will be processed elsewhere). See note on write_sub_paths about global.
 216     fn write_sub_paths_truncated(&mut self, path: &'tcx hir::Path<'tcx>) {
 217         if let [segments @ .., _] = path.segments {
 218             self.write_segments(segments)
 219         }
 220     }
 221
 222     fn process_formals(&mut self, formals: &'tcx [hir::Param<'tcx>], qualname: &str) {
 223         for arg in formals {
 224             self.visit_pat(&arg.pat);
 225             let mut collector = PathCollector::new(self.tcx);
 226             collector.visit_pat(&arg.pat);
 227
 228             for (hir_id, ident, ..) in collector.collected_idents {
 229                 let typ = match self.save_ctxt.typeck_results().node_type_opt(hir_id) {
 230                     Some(s) => s.to_string(),
 231                     None => continue,
 232                 };
 233                 if !self.span.filter_generated(ident.span) {
 234                     let id = id_from_hir_id(hir_id, &self.save_ctxt);
 235                     let span = self.span_from_span(ident.span);
 236
 237                     self.dumper.dump_def(
 238                         &Access { public: false, reachable: false },
 239                         Def {
 240                             kind: DefKind::Local,
 241                             id,
 242                             span,
 243                             name: ident.to_string(),
 244                             qualname: format!("{}::{}", qualname, ident.to_string()),
 245                             value: typ,
 246                             parent: None,
 247                             children: vec![],
 248                             decl_id: None,
 249                             docs: String::new(),
 250                             sig: None,
 251                             attributes: vec![],
 252                         },
 253                     );
 254                 }
 255             }
 256         }
 257     }
 258
 259     fn process_method(
 260         &mut self,
 261         sig: &'tcx hir::FnSig<'tcx>,
 262         body: Option<hir::BodyId>,
 263         hir_id: hir::HirId,
 264         ident: Ident,
 265         generics: &'tcx hir::Generics<'tcx>,
 266         vis: &hir::Visibility<'tcx>,
 267         span: Span,
 268     ) {
 269         debug!("process_method: {}:{}", hir_id, ident);
 270
 271         let map = &self.tcx.hir();
 272         self.nest_typeck_results(map.local_def_id(hir_id), |v| {
 273             if let Some(mut method_data) = v.save_ctxt.get_method_data(hir_id, ident, span) {
 274                 if let Some(body) = body {
 275                     v.process_formals(map.body(body).params, &method_data.qualname);
 276                 }
 277                 v.process_generic_params(&generics, &method_data.qualname, hir_id);
 278
 279                 method_data.value =
 280                     fn_to_string(sig.decl, sig.header, Some(ident.name), generics, vis, &[], None);
 281                 method_data.sig = sig::method_signature(hir_id, ident, generics, sig, &v.save_ctxt);
 282
 283                 v.dumper.dump_def(&access_from_vis!(v.save_ctxt, vis, hir_id), method_data);
 284             }
 285
 286             // walk arg and return types
 287             for arg in sig.decl.inputs {
 288                 v.visit_ty(arg);
 289             }
 290
 291             if let hir::FnRetTy::Return(ref ret_ty) = sig.decl.output {
 292                 v.visit_ty(ret_ty)
 293             }
 294
 295             // walk the fn body
 296             if let Some(body) = body {
 297                 v.visit_expr(&map.body(body).value);
 298             }
 299         });
 300     }
 301
 302     fn process_struct_field_def(
 303         &mut self,
 304         field: &'tcx hir::StructField<'tcx>,
 305         parent_id: hir::HirId,
 306     ) {
 307         let field_data = self.save_ctxt.get_field_data(field, parent_id);
 308         if let Some(field_data) = field_data {
 309             self.dumper.dump_def(&access_from!(self.save_ctxt, field, field.hir_id), field_data);
 310         }
 311     }
 312
 313     // Dump generic params bindings, then visit_generics
 314     fn process_generic_params(
 315         &mut self,
 316         generics: &'tcx hir::Generics<'tcx>,
 317         prefix: &str,
 318         id: hir::HirId,
 319     ) {
 320         for param in generics.params {
 321             match param.kind {
 322                 hir::GenericParamKind::Lifetime { .. } => {}
 323                 hir::GenericParamKind::Type { .. } => {
 324                     let param_ss = param.name.ident().span;
 325                     let name = escape(self.span.snippet(param_ss));
 326                     // Append $id to name to make sure each one is unique.
 327                     let qualname = format!("{}::{}${}", prefix, name, id);
 328                     if !self.span.filter_generated(param_ss) {
 329                         let id = id_from_hir_id(param.hir_id, &self.save_ctxt);
 330                         let span = self.span_from_span(param_ss);
 331
 332                         self.dumper.dump_def(
 333                             &Access { public: false, reachable: false },
 334                             Def {
 335                                 kind: DefKind::Type,
 336                                 id,
 337                                 span,
 338                                 name,
 339                                 qualname,
 340                                 value: String::new(),
 341                                 parent: None,
 342                                 children: vec![],
 343                                 decl_id: None,
 344                                 docs: String::new(),
 345                                 sig: None,
 346                                 attributes: vec![],
 347                             },
 348                         );
 349                     }
 350                 }
 351                 hir::GenericParamKind::Const { .. } => {}
 352             }
 353         }
 354         self.visit_generics(generics);
 355     }
 356
 357     fn process_fn(
 358         &mut self,
 359         item: &'tcx hir::Item<'tcx>,
 360         decl: &'tcx hir::FnDecl<'tcx>,
 361         _header: &'tcx hir::FnHeader,
 362         ty_params: &'tcx hir::Generics<'tcx>,
 363         body: hir::BodyId,
 364     ) {
 365         let map = &self.tcx.hir();
 366         self.nest_typeck_results(map.local_def_id(item.hir_id), |v| {
 367             let body = map.body(body);
 368             if let Some(fn_data) = v.save_ctxt.get_item_data(item) {
 369                 down_cast_data!(fn_data, DefData, item.span);
 370                 v.process_formals(body.params, &fn_data.qualname);
 371                 v.process_generic_params(ty_params, &fn_data.qualname, item.hir_id);
 372
 373                 v.dumper.dump_def(&access_from!(v.save_ctxt, item, item.hir_id), fn_data);
 374             }
 375
 376             for arg in decl.inputs {
 377                 v.visit_ty(arg)
 378             }
 379
 380             if let hir::FnRetTy::Return(ref ret_ty) = decl.output {
 381                 v.visit_ty(ret_ty)
 382             }
 383
 384             v.visit_expr(&body.value);
 385         });
 386     }
 387
 388     fn process_static_or_const_item(
 389         &mut self,
 390         item: &'tcx hir::Item<'tcx>,
 391         typ: &'tcx hir::Ty<'tcx>,
 392         expr: &'tcx hir::Expr<'tcx>,
 393     ) {
 394         self.nest_typeck_results(self.tcx.hir().local_def_id(item.hir_id), |v| {
 395             if let Some(var_data) = v.save_ctxt.get_item_data(item) {
 396                 down_cast_data!(var_data, DefData, item.span);
 397                 v.dumper.dump_def(&access_from!(v.save_ctxt, item, item.hir_id), var_data);
 398             }
 399             v.visit_ty(&typ);
 400             v.visit_expr(expr);
 401         });
 402     }
 403
 404     fn process_assoc_const(
 405         &mut self,
 406         hir_id: hir::HirId,
 407         ident: Ident,
 408         typ: &'tcx hir::Ty<'tcx>,
 409         expr: Option<&'tcx hir::Expr<'tcx>>,
 410         parent_id: DefId,
 411         vis: &hir::Visibility<'tcx>,
 412         attrs: &'tcx [ast::Attribute],
 413     ) {
 414         let qualname =
 415             format!("::{}", self.tcx.def_path_str(self.tcx.hir().local_def_id(hir_id).to_def_id()));
 416
 417         if !self.span.filter_generated(ident.span) {
 418             let sig = sig::assoc_const_signature(hir_id, ident.name, typ, expr, &self.save_ctxt);
 419             let span = self.span_from_span(ident.span);
 420
 421             self.dumper.dump_def(
 422                 &access_from_vis!(self.save_ctxt, vis, hir_id),
 423                 Def {
 424                     kind: DefKind::Const,
 425                     id: id_from_hir_id(hir_id, &self.save_ctxt),
 426                     span,
 427                     name: ident.name.to_string(),
 428                     qualname,
 429                     value: ty_to_string(&typ),
 430                     parent: Some(id_from_def_id(parent_id)),
 431                     children: vec![],
 432                     decl_id: None,
 433                     docs: self.save_ctxt.docs_for_attrs(attrs),
 434                     sig,
 435                     attributes: lower_attributes(attrs.to_owned(), &self.save_ctxt),
 436                 },
 437             );
 438         }
 439
 440         // walk type and init value
 441         self.nest_typeck_results(self.tcx.hir().local_def_id(hir_id), |v| {
 442             v.visit_ty(typ);
 443             if let Some(expr) = expr {
 444                 v.visit_expr(expr);
 445             }
 446         });
 447     }
 448
 449     // FIXME tuple structs should generate tuple-specific data.
 450     fn process_struct(
 451         &mut self,
 452         item: &'tcx hir::Item<'tcx>,
 453         def: &'tcx hir::VariantData<'tcx>,
 454         ty_params: &'tcx hir::Generics<'tcx>,
 455     ) {
 456         debug!("process_struct {:?} {:?}", item, item.span);
 457         let name = item.ident.to_string();
 458         let qualname = format!(
 459             "::{}",
 460             self.tcx.def_path_str(self.tcx.hir().local_def_id(item.hir_id).to_def_id())
 461         );
 462
 463         let kind = match item.kind {
 464             hir::ItemKind::Struct(_, _) => DefKind::Struct,
 465             hir::ItemKind::Union(_, _) => DefKind::Union,
 466             _ => unreachable!(),
 467         };
 468
 469         let (value, fields) = match item.kind {
 470             hir::ItemKind::Struct(hir::VariantData::Struct(ref fields, ..), ..)
 471             | hir::ItemKind::Union(hir::VariantData::Struct(ref fields, ..), ..) => {
 472                 let include_priv_fields = !self.save_ctxt.config.pub_only;
 473                 let fields_str = fields
 474                     .iter()
 475                     .filter_map(|f| {
 476                         if include_priv_fields || f.vis.node.is_pub() {
 477                             Some(f.ident.to_string())
 478                         } else {
 479                             None
 480                         }
 481                     })
 482                     .collect::<Vec<_>>()
 483                     .join(", ");
 484                 let value = format!("{} {{ {} }}", name, fields_str);
 485                 (value, fields.iter().map(|f| id_from_hir_id(f.hir_id, &self.save_ctxt)).collect())
 486             }
 487             _ => (String::new(), vec![]),
 488         };
 489
 490         if !self.span.filter_generated(item.ident.span) {
 491             let span = self.span_from_span(item.ident.span);
 492             self.dumper.dump_def(
 493                 &access_from!(self.save_ctxt, item, item.hir_id),
 494                 Def {
 495                     kind,
 496                     id: id_from_hir_id(item.hir_id, &self.save_ctxt),
 497                     span,
 498                     name,
 499                     qualname: qualname.clone(),
 500                     value,
 501                     parent: None,
 502                     children: fields,
 503                     decl_id: None,
 504                     docs: self.save_ctxt.docs_for_attrs(&item.attrs),
 505                     sig: sig::item_signature(item, &self.save_ctxt),
 506                     attributes: lower_attributes(item.attrs.to_vec(), &self.save_ctxt),
 507                 },
 508             );
 509         }
 510
 511         self.nest_typeck_results(self.tcx.hir().local_def_id(item.hir_id), |v| {
 512             for field in def.fields() {
 513                 v.process_struct_field_def(field, item.hir_id);
 514                 v.visit_ty(&field.ty);
 515             }
 516
 517             v.process_generic_params(ty_params, &qualname, item.hir_id);
 518         });
 519     }
 520
 521     fn process_enum(
 522         &mut self,
 523         item: &'tcx hir::Item<'tcx>,
 524         enum_definition: &'tcx hir::EnumDef<'tcx>,
 525         ty_params: &'tcx hir::Generics<'tcx>,
 526     ) {
 527         let enum_data = self.save_ctxt.get_item_data(item);
 528         let enum_data = match enum_data {
 529             None => return,
 530             Some(data) => data,
 531         };
 532         down_cast_data!(enum_data, DefData, item.span);
 533
 534         let access = access_from!(self.save_ctxt, item, item.hir_id);
 535
 536         for variant in enum_definition.variants {
 537             let name = variant.ident.name.to_string();
 538             let qualname = format!("{}::{}", enum_data.qualname, name);
 539             let name_span = variant.ident.span;
 540
 541             match variant.data {
 542                 hir::VariantData::Struct(ref fields, ..) => {
 543                     let fields_str =
 544                         fields.iter().map(|f| f.ident.to_string()).collect::<Vec<_>>().join(", ");
 545                     let value = format!("{}::{} {{ {} }}", enum_data.name, name, fields_str);
 546                     if !self.span.filter_generated(name_span) {
 547                         let span = self.span_from_span(name_span);
 548                         let id = id_from_hir_id(variant.id, &self.save_ctxt);
 549                         let parent = Some(id_from_hir_id(item.hir_id, &self.save_ctxt));
 550
 551                         self.dumper.dump_def(
 552                             &access,
 553                             Def {
 554                                 kind: DefKind::StructVariant,
 555                                 id,
 556                                 span,
 557                                 name,
 558                                 qualname,
 559                                 value,
 560                                 parent,
 561                                 children: vec![],
 562                                 decl_id: None,
 563                                 docs: self.save_ctxt.docs_for_attrs(&variant.attrs),
 564                                 sig: sig::variant_signature(variant, &self.save_ctxt),
 565                                 attributes: lower_attributes(
 566                                     variant.attrs.to_vec(),
 567                                     &self.save_ctxt,
 568                                 ),
 569                             },
 570                         );
 571                     }
 572                 }
 573                 ref v => {
 574                     let mut value = format!("{}::{}", enum_data.name, name);
 575                     if let &hir::VariantData::Tuple(ref fields, _) = v {
 576                         value.push('(');
 577                         value.push_str(
 578                             &fields
 579                                 .iter()
 580                                 .map(|f| ty_to_string(&f.ty))
 581                                 .collect::<Vec<_>>()
 582                                 .join(", "),
 583                         );
 584                         value.push(')');
 585                     }
 586                     if !self.span.filter_generated(name_span) {
 587                         let span = self.span_from_span(name_span);
 588                         let id = id_from_hir_id(variant.id, &self.save_ctxt);
 589                         let parent = Some(id_from_hir_id(item.hir_id, &self.save_ctxt));
 590
 591                         self.dumper.dump_def(
 592                             &access,
 593                             Def {
 594                                 kind: DefKind::TupleVariant,
 595                                 id,
 596                                 span,
 597                                 name,
 598                                 qualname,
 599                                 value,
 600                                 parent,
 601                                 children: vec![],
 602                                 decl_id: None,
 603                                 docs: self.save_ctxt.docs_for_attrs(&variant.attrs),
 604                                 sig: sig::variant_signature(variant, &self.save_ctxt),
 605                                 attributes: lower_attributes(
 606                                     variant.attrs.to_vec(),
 607                                     &self.save_ctxt,
 608                                 ),
 609                             },
 610                         );
 611                     }
 612                 }
 613             }
 614
 615             for field in variant.data.fields() {
 616                 self.process_struct_field_def(field, variant.id);
 617                 self.visit_ty(field.ty);
 618             }
 619         }
 620         self.process_generic_params(ty_params, &enum_data.qualname, item.hir_id);
 621         self.dumper.dump_def(&access, enum_data);
 622     }
 623
 624     fn process_impl(
 625         &mut self,
 626         item: &'tcx hir::Item<'tcx>,
 627         generics: &'tcx hir::Generics<'tcx>,
 628         trait_ref: &'tcx Option<hir::TraitRef<'tcx>>,
 629         typ: &'tcx hir::Ty<'tcx>,
 630         impl_items: &'tcx [hir::ImplItemRef<'tcx>],
 631     ) {
 632         if let Some(impl_data) = self.save_ctxt.get_item_data(item) {
 633             if !self.span.filter_generated(item.span) {
 634                 if let super::Data::RelationData(rel, imp) = impl_data {
 635                     self.dumper.dump_relation(rel);
 636                     self.dumper.dump_impl(imp);
 637                 } else {
 638                     span_bug!(item.span, "unexpected data kind: {:?}", impl_data);
 639                 }
 640             }
 641         }
 642
 643         let map = &self.tcx.hir();
 644         self.nest_typeck_results(map.local_def_id(item.hir_id), |v| {
 645             v.visit_ty(&typ);
 646             if let &Some(ref trait_ref) = trait_ref {
 647                 v.process_path(trait_ref.hir_ref_id, &hir::QPath::Resolved(None, &trait_ref.path));
 648             }
 649             v.process_generic_params(generics, "", item.hir_id);
 650             for impl_item in impl_items {
 651                 v.process_impl_item(
 652                     map.impl_item(impl_item.id),
 653                     map.local_def_id(item.hir_id).to_def_id(),
 654                 );
 655             }
 656         });
 657     }
 658
 659     fn process_trait(
 660         &mut self,
 661         item: &'tcx hir::Item<'tcx>,
 662         generics: &'tcx hir::Generics<'tcx>,
 663         trait_refs: hir::GenericBounds<'tcx>,
 664         methods: &'tcx [hir::TraitItemRef],
 665     ) {
 666         let name = item.ident.to_string();
 667         let qualname = format!(
 668             "::{}",
 669             self.tcx.def_path_str(self.tcx.hir().local_def_id(item.hir_id).to_def_id())
 670         );
 671         let mut val = name.clone();
 672         if !generics.params.is_empty() {
 673             val.push_str(&generic_params_to_string(generics.params));
 674         }
 675         if !trait_refs.is_empty() {
 676             val.push_str(": ");
 677             val.push_str(&bounds_to_string(trait_refs));
 678         }
 679         if !self.span.filter_generated(item.ident.span) {
 680             let id = id_from_hir_id(item.hir_id, &self.save_ctxt);
 681             let span = self.span_from_span(item.ident.span);
 682             let children =
 683                 methods.iter().map(|i| id_from_hir_id(i.id.hir_id, &self.save_ctxt)).collect();
 684             self.dumper.dump_def(
 685                 &access_from!(self.save_ctxt, item, item.hir_id),
 686                 Def {
 687                     kind: DefKind::Trait,
 688                     id,
 689                     span,
 690                     name,
 691                     qualname: qualname.clone(),
 692                     value: val,
 693                     parent: None,
 694                     children,
 695                     decl_id: None,
 696                     docs: self.save_ctxt.docs_for_attrs(&item.attrs),
 697                     sig: sig::item_signature(item, &self.save_ctxt),
 698                     attributes: lower_attributes(item.attrs.to_vec(), &self.save_ctxt),
 699                 },
 700             );
 701         }
 702
 703         // super-traits
 704         for super_bound in trait_refs.iter() {
 705             let (def_id, sub_span) = match *super_bound {
 706                 hir::GenericBound::Trait(ref trait_ref, _) => (
 707                     self.lookup_def_id(trait_ref.trait_ref.hir_ref_id),
 708                     trait_ref.trait_ref.path.segments.last().unwrap().ident.span,
 709                 ),
 710                 hir::GenericBound::LangItemTrait(lang_item, span, _, _) => {
 711                     (Some(self.tcx.require_lang_item(lang_item, Some(span))), span)
 712                 }
 713                 hir::GenericBound::Outlives(..) => continue,
 714             };
 715
 716             if let Some(id) = def_id {
 717                 if !self.span.filter_generated(sub_span) {
 718                     let span = self.span_from_span(sub_span);
 719                     self.dumper.dump_ref(Ref {
 720                         kind: RefKind::Type,
 721                         span: span.clone(),
 722                         ref_id: id_from_def_id(id),
 723                     });
 724
 725                     self.dumper.dump_relation(Relation {
 726                         kind: RelationKind::SuperTrait,
 727                         span,
 728                         from: id_from_def_id(id),
 729                         to: id_from_hir_id(item.hir_id, &self.save_ctxt),
 730                     });
 731                 }
 732             }
 733         }
 734
 735         // walk generics and methods
 736         self.process_generic_params(generics, &qualname, item.hir_id);
 737         for method in methods {
 738             let map = &self.tcx.hir();
 739             self.process_trait_item(
 740                 map.trait_item(method.id),
 741                 map.local_def_id(item.hir_id).to_def_id(),
 742             )
 743         }
 744     }
 745
 746     // `item` is the module in question, represented as an( item.
 747     fn process_mod(&mut self, item: &'tcx hir::Item<'tcx>) {
 748         if let Some(mod_data) = self.save_ctxt.get_item_data(item) {
 749             down_cast_data!(mod_data, DefData, item.span);
 750             self.dumper.dump_def(&access_from!(self.save_ctxt, item, item.hir_id), mod_data);
 751         }
 752     }
 753
 754     fn dump_path_ref(&mut self, id: hir::HirId, path: &hir::QPath<'tcx>) {
 755         let path_data = self.save_ctxt.get_path_data(id, path);
 756         if let Some(path_data) = path_data {
 757             self.dumper.dump_ref(path_data);
 758         }
 759     }
 760
 761     fn dump_path_segment_ref(&mut self, id: hir::HirId, segment: &hir::PathSegment<'tcx>) {
 762         let segment_data = self.save_ctxt.get_path_segment_data_with_id(segment, id);
 763         if let Some(segment_data) = segment_data {
 764             self.dumper.dump_ref(segment_data);
 765         }
 766     }
 767
 768     fn process_path(&mut self, id: hir::HirId, path: &hir::QPath<'tcx>) {
 769         if self.span.filter_generated(path.span()) {
 770             return;
 771         }
 772         self.dump_path_ref(id, path);
 773
 774         // Type arguments
 775         let segments = match path {
 776             hir::QPath::Resolved(ty, path) => {
 777                 if let Some(ty) = ty {
 778                     self.visit_ty(ty);
 779                 }
 780                 path.segments
 781             }
 782             hir::QPath::TypeRelative(ty, segment) => {
 783                 self.visit_ty(ty);
 784                 std::slice::from_ref(*segment)
 785             }
 786             hir::QPath::LangItem(..) => return,
 787         };
 788         for seg in segments {
 789             if let Some(ref generic_args) = seg.args {
 790                 for arg in generic_args.args {
 791                     if let hir::GenericArg::Type(ref ty) = arg {
 792                         self.visit_ty(ty);
 793                     }
 794                 }
 795             }
 796         }
 797
 798         if let hir::QPath::Resolved(_, path) = path {
 799             self.write_sub_paths_truncated(path);
 800         }
 801     }
 802
 803     fn process_struct_lit(
 804         &mut self,
 805         ex: &'tcx hir::Expr<'tcx>,
 806         path: &'tcx hir::QPath<'tcx>,
 807         fields: &'tcx [hir::Field<'tcx>],
 808         variant: &'tcx ty::VariantDef,
 809         base: Option<&'tcx hir::Expr<'tcx>>,
 810     ) {
 811         if let Some(struct_lit_data) = self.save_ctxt.get_expr_data(ex) {
 812             if let hir::QPath::Resolved(_, path) = path {
 813                 self.write_sub_paths_truncated(path);
 814             }
 815             down_cast_data!(struct_lit_data, RefData, ex.span);
 816             if !generated_code(ex.span) {
 817                 self.dumper.dump_ref(struct_lit_data);
 818             }
 819
 820             for field in fields {
 821                 if let Some(field_data) = self.save_ctxt.get_field_ref_data(field, variant) {
 822                     self.dumper.dump_ref(field_data);
 823                 }
 824
 825                 self.visit_expr(&field.expr)
 826             }
 827         }
 828
 829         walk_list!(self, visit_expr, base);
 830     }
 831
 832     fn process_method_call(
 833         &mut self,
 834         ex: &'tcx hir::Expr<'tcx>,
 835         seg: &'tcx hir::PathSegment<'tcx>,
 836         args: &'tcx [hir::Expr<'tcx>],
 837     ) {
 838         debug!("process_method_call {:?} {:?}", ex, ex.span);
 839         if let Some(mcd) = self.save_ctxt.get_expr_data(ex) {
 840             down_cast_data!(mcd, RefData, ex.span);
 841             if !generated_code(ex.span) {
 842                 self.dumper.dump_ref(mcd);
 843             }
 844         }
 845
 846         // Explicit types in the turbo-fish.
 847         if let Some(generic_args) = seg.args {
 848             for arg in generic_args.args {
 849                 if let hir::GenericArg::Type(ty) = arg {
 850                     self.visit_ty(&ty)
 851                 };
 852             }
 853         }
 854
 855         // walk receiver and args
 856         walk_list!(self, visit_expr, args);
 857     }
 858
 859     fn process_pat(&mut self, p: &'tcx hir::Pat<'tcx>) {
 860         match p.kind {
 861             hir::PatKind::Struct(ref _path, fields, _) => {
 862                 // FIXME do something with _path?
 863                 let adt = match self.save_ctxt.typeck_results().node_type_opt(p.hir_id) {
 864                     Some(ty) if ty.ty_adt_def().is_some() => ty.ty_adt_def().unwrap(),
 865                     _ => {
 866                         intravisit::walk_pat(self, p);
 867                         return;
 868                     }
 869                 };
 870                 let variant = adt.variant_of_res(self.save_ctxt.get_path_res(p.hir_id));
 871
 872                 for field in fields {
 873                     if let Some(index) = self.tcx.find_field_index(field.ident, variant) {
 874                         if !self.span.filter_generated(field.ident.span) {
 875                             let span = self.span_from_span(field.ident.span);
 876                             self.dumper.dump_ref(Ref {
 877                                 kind: RefKind::Variable,
 878                                 span,
 879                                 ref_id: id_from_def_id(variant.fields[index].did),
 880                             });
 881                         }
 882                     }
 883                     self.visit_pat(&field.pat);
 884                 }
 885             }
 886             _ => intravisit::walk_pat(self, p),
 887         }
 888     }
 889
 890     fn process_var_decl(&mut self, pat: &'tcx hir::Pat<'tcx>) {
 891         // The pattern could declare multiple new vars,
 892         // we must walk the pattern and collect them all.
 893         let mut collector = PathCollector::new(self.tcx);
 894         collector.visit_pat(&pat);
 895         self.visit_pat(&pat);
 896
 897         // Process collected paths.
 898         for (id, ident, _) in collector.collected_idents {
 899             let res = self.save_ctxt.get_path_res(id);
 900             match res {
 901                 Res::Local(hir_id) => {
 902                     let typ = self
 903                         .save_ctxt
 904                         .typeck_results()
 905                         .node_type_opt(hir_id)
 906                         .map(|t| t.to_string())
 907                         .unwrap_or_default();
 908
 909                     // Rust uses the id of the pattern for var lookups, so we'll use it too.
 910                     if !self.span.filter_generated(ident.span) {
 911                         let qualname = format!("{}${}", ident.to_string(), hir_id);
 912                         let id = id_from_hir_id(hir_id, &self.save_ctxt);
 913                         let span = self.span_from_span(ident.span);
 914
 915                         self.dumper.dump_def(
 916                             &Access { public: false, reachable: false },
 917                             Def {
 918                                 kind: DefKind::Local,
 919                                 id,
 920                                 span,
 921                                 name: ident.to_string(),
 922                                 qualname,
 923                                 value: typ,
 924                                 parent: None,
 925                                 children: vec![],
 926                                 decl_id: None,
 927                                 docs: String::new(),
 928                                 sig: None,
 929                                 attributes: vec![],
 930                             },
 931                         );
 932                     }
 933                 }
 934                 Res::Def(
 935                     HirDefKind::Ctor(..)
 936                     | HirDefKind::Const
 937                     | HirDefKind::AssocConst
 938                     | HirDefKind::Struct
 939                     | HirDefKind::Variant
 940                     | HirDefKind::TyAlias
 941                     | HirDefKind::AssocTy,
 942                     _,
 943                 )
 944                 | Res::SelfTy(..) => {
 945                     self.dump_path_segment_ref(id, &hir::PathSegment::from_ident(ident));
 946                 }
 947                 def => {
 948                     error!("unexpected definition kind when processing collected idents: {:?}", def)
 949                 }
 950             }
 951         }
 952
 953         for (id, ref path) in collector.collected_paths {
 954             self.process_path(id, path);
 955         }
 956     }
 957
 958     /// Extracts macro use and definition information from the AST node defined
 959     /// by the given NodeId, using the expansion information from the node's
 960     /// span.
 961     ///
 962     /// If the span is not macro-generated, do nothing, else use callee and
 963     /// callsite spans to record macro definition and use data, using the
 964     /// mac_uses and mac_defs sets to prevent multiples.
 965     fn process_macro_use(&mut self, _span: Span) {
 966         // FIXME if we're not dumping the defs (see below), there is no point
 967         // dumping refs either.
 968         // let source_span = span.source_callsite();
 969         // if !self.macro_calls.insert(source_span) {
 970         //     return;
 971         // }
 972
 973         // let data = match self.save_ctxt.get_macro_use_data(span) {
 974         //     None => return,
 975         //     Some(data) => data,
 976         // };
 977
 978         // self.dumper.macro_use(data);
 979
 980         // FIXME write the macro def
 981         // let mut hasher = DefaultHasher::new();
 982         // data.callee_span.hash(&mut hasher);
 983         // let hash = hasher.finish();
 984         // let qualname = format!("{}::{}", data.name, hash);
 985         // Don't write macro definition for imported macros
 986         // if !self.mac_defs.contains(&data.callee_span)
 987         //     && !data.imported {
 988         //     self.mac_defs.insert(data.callee_span);
 989         //     if let Some(sub_span) = self.span.span_for_macro_def_name(data.callee_span) {
 990         //         self.dumper.macro_data(MacroData {
 991         //             span: sub_span,
 992         //             name: data.name.clone(),
 993         //             qualname: qualname.clone(),
 994         //             // FIXME where do macro docs come from?
 995         //             docs: String::new(),
 996         //         }.lower(self.tcx));
 997         //     }
 998         // }
 999     }
1000
1001     fn process_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>, trait_id: DefId) {
1002         self.process_macro_use(trait_item.span);
1003         let vis_span = trait_item.span.shrink_to_lo();
1004         match trait_item.kind {
1005             hir::TraitItemKind::Const(ref ty, body) => {
1006                 let body = body.map(|b| &self.tcx.hir().body(b).value);
1007                 let respan = respan(vis_span, hir::VisibilityKind::Public);
1008                 self.process_assoc_const(
1009                     trait_item.hir_id,
1010                     trait_item.ident,
1011                     &ty,
1012                     body,
1013                     trait_id,
1014                     &respan,
1015                     &trait_item.attrs,
1016                 );
1017             }
1018             hir::TraitItemKind::Fn(ref sig, ref trait_fn) => {
1019                 let body =
1020                     if let hir::TraitFn::Provided(body) = trait_fn { Some(*body) } else { None };
1021                 let respan = respan(vis_span, hir::VisibilityKind::Public);
1022                 self.process_method(
1023                     sig,
1024                     body,
1025                     trait_item.hir_id,
1026                     trait_item.ident,
1027                     &trait_item.generics,
1028                     &respan,
1029                     trait_item.span,
1030                 );
1031             }
1032             hir::TraitItemKind::Type(ref bounds, ref default_ty) => {
1033                 // FIXME do something with _bounds (for type refs)
1034                 let name = trait_item.ident.name.to_string();
1035                 let qualname = format!(
1036                     "::{}",
1037                     self.tcx
1038                         .def_path_str(self.tcx.hir().local_def_id(trait_item.hir_id).to_def_id())
1039                 );
1040
1041                 if !self.span.filter_generated(trait_item.ident.span) {
1042                     let span = self.span_from_span(trait_item.ident.span);
1043                     let id = id_from_hir_id(trait_item.hir_id, &self.save_ctxt);
1044
1045                     self.dumper.dump_def(
1046                         &Access { public: true, reachable: true },
1047                         Def {
1048                             kind: DefKind::Type,
1049                             id,
1050                             span,
1051                             name,
1052                             qualname,
1053                             value: self.span.snippet(trait_item.span),
1054                             parent: Some(id_from_def_id(trait_id)),
1055                             children: vec![],
1056                             decl_id: None,
1057                             docs: self.save_ctxt.docs_for_attrs(&trait_item.attrs),
1058                             sig: sig::assoc_type_signature(
1059                                 trait_item.hir_id,
1060                                 trait_item.ident,
1061                                 Some(bounds),
1062                                 default_ty.as_ref().map(|ty| &**ty),
1063                                 &self.save_ctxt,
1064                             ),
1065                             attributes: lower_attributes(
1066                                 trait_item.attrs.to_vec(),
1067                                 &self.save_ctxt,
1068                             ),
1069                         },
1070                     );
1071                 }
1072
1073                 if let &Some(ref default_ty) = default_ty {
1074                     self.visit_ty(default_ty)
1075                 }
1076             }
1077         }
1078     }
1079
1080     fn process_impl_item(&mut self, impl_item: &'tcx hir::ImplItem<'tcx>, impl_id: DefId) {
1081         self.process_macro_use(impl_item.span);
1082         match impl_item.kind {
1083             hir::ImplItemKind::Const(ref ty, body) => {
1084                 let body = self.tcx.hir().body(body);
1085                 self.process_assoc_const(
1086                     impl_item.hir_id,
1087                     impl_item.ident,
1088                     &ty,
1089                     Some(&body.value),
1090                     impl_id,
1091                     &impl_item.vis,
1092                     &impl_item.attrs,
1093                 );
1094             }
1095             hir::ImplItemKind::Fn(ref sig, body) => {
1096                 self.process_method(
1097                     sig,
1098                     Some(body),
1099                     impl_item.hir_id,
1100                     impl_item.ident,
1101                     &impl_item.generics,
1102                     &impl_item.vis,
1103                     impl_item.span,
1104                 );
1105             }
1106             hir::ImplItemKind::TyAlias(ref ty) => {
1107                 // FIXME: uses of the assoc type should ideally point to this
1108                 // 'def' and the name here should be a ref to the def in the
1109                 // trait.
1110                 self.visit_ty(ty)
1111             }
1112         }
1113     }
1114
1115     pub(crate) fn process_crate(&mut self, krate: &'tcx hir::Crate<'tcx>) {
1116         let id = hir::CRATE_HIR_ID;
1117         let qualname =
1118             format!("::{}", self.tcx.def_path_str(self.tcx.hir().local_def_id(id).to_def_id()));
1119
1120         let sm = self.tcx.sess.source_map();
1121         let filename = sm.span_to_filename(krate.item.span);
1122         let data_id = id_from_hir_id(id, &self.save_ctxt);
1123         let children = krate
1124             .item
1125             .module
1126             .item_ids
1127             .iter()
1128             .map(|i| id_from_hir_id(i.id, &self.save_ctxt))
1129             .collect();
1130         let span = self.span_from_span(krate.item.span);
1131
1132         self.dumper.dump_def(
1133             &Access { public: true, reachable: true },
1134             Def {
1135                 kind: DefKind::Mod,
1136                 id: data_id,
1137                 name: String::new(),
1138                 qualname,
1139                 span,
1140                 value: filename.to_string(),
1141                 children,
1142                 parent: None,
1143                 decl_id: None,
1144                 docs: self.save_ctxt.docs_for_attrs(krate.item.attrs),
1145                 sig: None,
1146                 attributes: lower_attributes(krate.item.attrs.to_owned(), &self.save_ctxt),
1147             },
1148         );
1149         intravisit::walk_crate(self, krate);
1150     }
1151
1152     fn process_bounds(&mut self, bounds: hir::GenericBounds<'tcx>) {
1153         for bound in bounds {
1154             if let hir::GenericBound::Trait(ref trait_ref, _) = *bound {
1155                 self.process_path(
1156                     trait_ref.trait_ref.hir_ref_id,
1157                     &hir::QPath::Resolved(None, &trait_ref.trait_ref.path),
1158                 )
1159             }
1160         }
1161     }
1162 }
1163
1164 impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
1165     type Map = Map<'tcx>;
1166
1167     fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
1168         intravisit::NestedVisitorMap::All(self.tcx.hir())
1169     }
1170
1171     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
1172         self.process_macro_use(item.span);
1173         match item.kind {
1174             hir::ItemKind::Use(path, hir::UseKind::Single) => {
1175                 let sub_span = path.segments.last().unwrap().ident.span;
1176                 if !self.span.filter_generated(sub_span) {
1177                     let access = access_from!(self.save_ctxt, item, item.hir_id);
1178                     let ref_id = self.lookup_def_id(item.hir_id).map(id_from_def_id);
1179                     let span = self.span_from_span(sub_span);
1180                     let parent = self
1181                         .save_ctxt
1182                         .tcx
1183                         .hir()
1184                         .opt_local_def_id(item.hir_id)
1185                         .and_then(|id| self.save_ctxt.tcx.parent(id.to_def_id()))
1186                         .map(id_from_def_id);
1187                     self.dumper.import(
1188                         &access,
1189                         Import {
1190                             kind: ImportKind::Use,
1191                             ref_id,
1192                             span,
1193                             alias_span: None,
1194                             name: item.ident.to_string(),
1195                             value: String::new(),
1196                             parent,
1197                         },
1198                     );
1199                     self.write_sub_paths_truncated(&path);
1200                 }
1201             }
1202             hir::ItemKind::Use(path, hir::UseKind::Glob) => {
1203                 // Make a comma-separated list of names of imported modules.
1204                 let def_id = self.tcx.hir().local_def_id(item.hir_id);
1205                 let names = self.tcx.names_imported_by_glob_use(def_id);
1206                 let names: Vec<_> = names.iter().map(|n| n.to_string()).collect();
1207
1208                 // Otherwise it's a span with wrong macro expansion info, which
1209                 // we don't want to track anyway, since it's probably macro-internal `use`
1210                 if let Some(sub_span) =
1211                     self.span.sub_span_of_token(item.span, token::BinOp(token::Star))
1212                 {
1213                     if !self.span.filter_generated(item.span) {
1214                         let access = access_from!(self.save_ctxt, item, item.hir_id);
1215                         let span = self.span_from_span(sub_span);
1216                         let parent = self
1217                             .save_ctxt
1218                             .tcx
1219                             .hir()
1220                             .opt_local_def_id(item.hir_id)
1221                             .and_then(|id| self.save_ctxt.tcx.parent(id.to_def_id()))
1222                             .map(id_from_def_id);
1223                         self.dumper.import(
1224                             &access,
1225                             Import {
1226                                 kind: ImportKind::GlobUse,
1227                                 ref_id: None,
1228                                 span,
1229                                 alias_span: None,
1230                                 name: "*".to_owned(),
1231                                 value: names.join(", "),
1232                                 parent,
1233                             },
1234                         );
1235                         self.write_sub_paths(&path);
1236                     }
1237                 }
1238             }
1239             hir::ItemKind::ExternCrate(_) => {
1240                 let name_span = item.ident.span;
1241                 if !self.span.filter_generated(name_span) {
1242                     let span = self.span_from_span(name_span);
1243                     let parent = self
1244                         .save_ctxt
1245                         .tcx
1246                         .hir()
1247                         .opt_local_def_id(item.hir_id)
1248                         .and_then(|id| self.save_ctxt.tcx.parent(id.to_def_id()))
1249                         .map(id_from_def_id);
1250                     self.dumper.import(
1251                         &Access { public: false, reachable: false },
1252                         Import {
1253                             kind: ImportKind::ExternCrate,
1254                             ref_id: None,
1255                             span,
1256                             alias_span: None,
1257                             name: item.ident.to_string(),
1258                             value: String::new(),
1259                             parent,
1260                         },
1261                     );
1262                 }
1263             }
1264             hir::ItemKind::Fn(ref sig, ref ty_params, body) => {
1265                 self.process_fn(item, sig.decl, &sig.header, ty_params, body)
1266             }
1267             hir::ItemKind::Static(ref typ, _, body) => {
1268                 let body = self.tcx.hir().body(body);
1269                 self.process_static_or_const_item(item, typ, &body.value)
1270             }
1271             hir::ItemKind::Const(ref typ, body) => {
1272                 let body = self.tcx.hir().body(body);
1273                 self.process_static_or_const_item(item, typ, &body.value)
1274             }
1275             hir::ItemKind::Struct(ref def, ref ty_params)
1276             | hir::ItemKind::Union(ref def, ref ty_params) => {
1277                 self.process_struct(item, def, ty_params)
1278             }
1279             hir::ItemKind::Enum(ref def, ref ty_params) => self.process_enum(item, def, ty_params),
1280             hir::ItemKind::Impl { ref generics, ref of_trait, ref self_ty, ref items, .. } => {
1281                 self.process_impl(item, generics, of_trait, &self_ty, items)
1282             }
1283             hir::ItemKind::Trait(_, _, ref generics, ref trait_refs, methods) => {
1284                 self.process_trait(item, generics, trait_refs, methods)
1285             }
1286             hir::ItemKind::Mod(ref m) => {
1287                 self.process_mod(item);
1288                 intravisit::walk_mod(self, m, item.hir_id);
1289             }
1290             hir::ItemKind::TyAlias(ty, ref generics) => {
1291                 let qualname = format!(
1292                     "::{}",
1293                     self.tcx.def_path_str(self.tcx.hir().local_def_id(item.hir_id).to_def_id())
1294                 );
1295                 let value = ty_to_string(&ty);
1296                 if !self.span.filter_generated(item.ident.span) {
1297                     let span = self.span_from_span(item.ident.span);
1298                     let id = id_from_hir_id(item.hir_id, &self.save_ctxt);
1299
1300                     self.dumper.dump_def(
1301                         &access_from!(self.save_ctxt, item, item.hir_id),
1302                         Def {
1303                             kind: DefKind::Type,
1304                             id,
1305                             span,
1306                             name: item.ident.to_string(),
1307                             qualname: qualname.clone(),
1308                             value,
1309                             parent: None,
1310                             children: vec![],
1311                             decl_id: None,
1312                             docs: self.save_ctxt.docs_for_attrs(&item.attrs),
1313                             sig: sig::item_signature(item, &self.save_ctxt),
1314                             attributes: lower_attributes(item.attrs.to_vec(), &self.save_ctxt),
1315                         },
1316                     );
1317                 }
1318
1319                 self.visit_ty(ty);
1320                 self.process_generic_params(generics, &qualname, item.hir_id);
1321             }
1322             _ => intravisit::walk_item(self, item),
1323         }
1324     }
1325
1326     fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
1327         for param in generics.params {
1328             match param.kind {
1329                 hir::GenericParamKind::Lifetime { .. } => {}
1330                 hir::GenericParamKind::Type { ref default, .. } => {
1331                     self.process_bounds(param.bounds);
1332                     if let Some(ref ty) = default {
1333                         self.visit_ty(ty);
1334                     }
1335                 }
1336                 hir::GenericParamKind::Const { ref ty } => {
1337                     self.process_bounds(param.bounds);
1338                     self.visit_ty(ty);
1339                 }
1340             }
1341         }
1342         for pred in generics.where_clause.predicates {
1343             if let hir::WherePredicate::BoundPredicate(ref wbp) = *pred {
1344                 self.process_bounds(wbp.bounds);
1345                 self.visit_ty(wbp.bounded_ty);
1346             }
1347         }
1348     }
1349
1350     fn visit_ty(&mut self, t: &'tcx hir::Ty<'tcx>) {
1351         self.process_macro_use(t.span);
1352         match t.kind {
1353             hir::TyKind::Path(ref path) => {
1354                 if generated_code(t.span) {
1355                     return;
1356                 }
1357
1358                 if let Some(id) = self.lookup_def_id(t.hir_id) {
1359                     let sub_span = path.last_segment_span();
1360                     let span = self.span_from_span(sub_span);
1361                     self.dumper.dump_ref(Ref {
1362                         kind: RefKind::Type,
1363                         span,
1364                         ref_id: id_from_def_id(id),
1365                     });
1366                 }
1367
1368                 if let hir::QPath::Resolved(_, path) = path {
1369                     self.write_sub_paths_truncated(path);
1370                 }
1371                 intravisit::walk_qpath(self, path, t.hir_id, t.span);
1372             }
1373             hir::TyKind::Array(ref ty, ref anon_const) => {
1374                 self.visit_ty(ty);
1375                 let map = self.tcx.hir();
1376                 self.nest_typeck_results(self.tcx.hir().local_def_id(anon_const.hir_id), |v| {
1377                     v.visit_expr(&map.body(anon_const.body).value)
1378                 });
1379             }
1380             hir::TyKind::OpaqueDef(item_id, _) => {
1381                 let item = self.tcx.hir().item(item_id.id);
1382                 self.nest_typeck_results(self.tcx.hir().local_def_id(item_id.id), |v| {
1383                     v.visit_item(item)
1384                 });
1385             }
1386             _ => intravisit::walk_ty(self, t),
1387         }
1388     }
1389
1390     fn visit_expr(&mut self, ex: &'tcx hir::Expr<'tcx>) {
1391         debug!("visit_expr {:?}", ex.kind);
1392         self.process_macro_use(ex.span);
1393         match ex.kind {
1394             hir::ExprKind::Struct(ref path, ref fields, ref base) => {
1395                 let hir_expr = self.save_ctxt.tcx.hir().expect_expr(ex.hir_id);
1396                 let adt = match self.save_ctxt.typeck_results().expr_ty_opt(&hir_expr) {
1397                     Some(ty) if ty.ty_adt_def().is_some() => ty.ty_adt_def().unwrap(),
1398                     _ => {
1399                         intravisit::walk_expr(self, ex);
1400                         return;
1401                     }
1402                 };
1403                 let res = self.save_ctxt.get_path_res(hir_expr.hir_id);
1404                 self.process_struct_lit(ex, path, fields, adt.variant_of_res(res), *base)
1405             }
1406             hir::ExprKind::MethodCall(ref seg, _, args, _) => {
1407                 self.process_method_call(ex, seg, args)
1408             }
1409             hir::ExprKind::Field(ref sub_ex, _) => {
1410                 self.visit_expr(&sub_ex);
1411
1412                 if let Some(field_data) = self.save_ctxt.get_expr_data(ex) {
1413                     down_cast_data!(field_data, RefData, ex.span);
1414                     if !generated_code(ex.span) {
1415                         self.dumper.dump_ref(field_data);
1416                     }
1417                 }
1418             }
1419             hir::ExprKind::Closure(_, ref decl, body, _fn_decl_span, _) => {
1420                 let id = format!("${}", ex.hir_id);
1421
1422                 // walk arg and return types
1423                 for ty in decl.inputs {
1424                     self.visit_ty(ty);
1425                 }
1426
1427                 if let hir::FnRetTy::Return(ref ret_ty) = decl.output {
1428                     self.visit_ty(ret_ty);
1429                 }
1430
1431                 // walk the body
1432                 let map = self.tcx.hir();
1433                 self.nest_typeck_results(self.tcx.hir().local_def_id(ex.hir_id), |v| {
1434                     let body = map.body(body);
1435                     v.process_formals(body.params, &id);
1436                     v.visit_expr(&body.value)
1437                 });
1438             }
1439             hir::ExprKind::Repeat(ref expr, ref anon_const) => {
1440                 self.visit_expr(expr);
1441                 let map = self.tcx.hir();
1442                 self.nest_typeck_results(self.tcx.hir().local_def_id(anon_const.hir_id), |v| {
1443                     v.visit_expr(&map.body(anon_const.body).value)
1444                 });
1445             }
1446             // In particular, we take this branch for call and path expressions,
1447             // where we'll index the idents involved just by continuing to walk.
1448             _ => intravisit::walk_expr(self, ex),
1449         }
1450     }
1451
1452     fn visit_pat(&mut self, p: &'tcx hir::Pat<'tcx>) {
1453         self.process_macro_use(p.span);
1454         self.process_pat(p);
1455     }
1456
1457     fn visit_arm(&mut self, arm: &'tcx hir::Arm<'tcx>) {
1458         self.process_var_decl(&arm.pat);
1459         if let Some(hir::Guard::If(expr)) = &arm.guard {
1460             self.visit_expr(expr);
1461         }
1462         self.visit_expr(&arm.body);
1463     }
1464
1465     fn visit_qpath(&mut self, path: &'tcx hir::QPath<'tcx>, id: hir::HirId, _: Span) {
1466         self.process_path(id, path);
1467     }
1468
1469     fn visit_stmt(&mut self, s: &'tcx hir::Stmt<'tcx>) {
1470         self.process_macro_use(s.span);
1471         intravisit::walk_stmt(self, s)
1472     }
1473
1474     fn visit_local(&mut self, l: &'tcx hir::Local<'tcx>) {
1475         self.process_macro_use(l.span);
1476         self.process_var_decl(&l.pat);
1477
1478         // Just walk the initialiser and type (don't want to walk the pattern again).
1479         walk_list!(self, visit_ty, &l.ty);
1480         walk_list!(self, visit_expr, &l.init);
1481     }
1482
1483     fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem<'tcx>) {
1484         let access = access_from!(self.save_ctxt, item, item.hir_id);
1485
1486         match item.kind {
1487             hir::ForeignItemKind::Fn(decl, _, ref generics) => {
1488                 if let Some(fn_data) = self.save_ctxt.get_extern_item_data(item) {
1489                     down_cast_data!(fn_data, DefData, item.span);
1490
1491                     self.process_generic_params(generics, &fn_data.qualname, item.hir_id);
1492                     self.dumper.dump_def(&access, fn_data);
1493                 }
1494
1495                 for ty in decl.inputs {
1496                     self.visit_ty(ty);
1497                 }
1498
1499                 if let hir::FnRetTy::Return(ref ret_ty) = decl.output {
1500                     self.visit_ty(ret_ty);
1501                 }
1502             }
1503             hir::ForeignItemKind::Static(ref ty, _) => {
1504                 if let Some(var_data) = self.save_ctxt.get_extern_item_data(item) {
1505                     down_cast_data!(var_data, DefData, item.span);
1506                     self.dumper.dump_def(&access, var_data);
1507                 }
1508
1509                 self.visit_ty(ty);
1510             }
1511             hir::ForeignItemKind::Type => {
1512                 if let Some(var_data) = self.save_ctxt.get_extern_item_data(item) {
1513                     down_cast_data!(var_data, DefData, item.span);
1514                     self.dumper.dump_def(&access, var_data);
1515                 }
1516             }
1517         }
1518     }
1519 }