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 Def IDs to identify objects. The
   5 //! tricky part is getting syntactic (span, source text) and semantic (reference
   6 //! Def IDs) 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 JsonDumper is used for
  14 //! recording the output.
  15
  16 use rustc::hir::def::Def as HirDef;
  17 use rustc::hir::def_id::DefId;
  18 use rustc::session::config::Input;
  19 use rustc::ty::{self, TyCtxt};
  20 use rustc_data_structures::fx::FxHashSet;
  21
  22 use std::path::Path;
  23 use std::env;
  24
  25 use syntax::ast::{self, Attribute, NodeId, PatKind, CRATE_NODE_ID};
  26 use syntax::parse::token;
  27 use syntax::visit::{self, Visitor};
  28 use syntax::print::pprust::{
  29     bounds_to_string,
  30     generic_params_to_string,
  31     ty_to_string
  32 };
  33 use syntax::ptr::P;
  34 use syntax::source_map::{Spanned, DUMMY_SP, respan};
  35 use syntax_pos::*;
  36
  37 use {escape, generated_code, lower_attributes, PathCollector, SaveContext};
  38 use json_dumper::{Access, DumpOutput, JsonDumper};
  39 use span_utils::SpanUtils;
  40 use sig;
  41
  42 use rls_data::{CompilationOptions, CratePreludeData, Def, DefKind, GlobalCrateId, Import,
  43                ImportKind, Ref, RefKind, Relation, RelationKind, SpanData};
  44
  45 macro_rules! down_cast_data {
  46     ($id:ident, $kind:ident, $sp:expr) => {
  47         let $id = if let super::Data::$kind(data) = $id {
  48             data
  49         } else {
  50             span_bug!($sp, "unexpected data kind: {:?}", $id);
  51         };
  52     };
  53 }
  54
  55 macro_rules! access_from {
  56     ($save_ctxt:expr, $vis:expr, $id:expr) => {
  57         Access {
  58             public: $vis.node.is_pub(),
  59             reachable: $save_ctxt.access_levels.is_reachable($id),
  60         }
  61     };
  62
  63     ($save_ctxt:expr, $item:expr) => {
  64         Access {
  65             public: $item.vis.node.is_pub(),
  66             reachable: $save_ctxt.access_levels.is_reachable($item.id),
  67         }
  68     };
  69 }
  70
  71 pub struct DumpVisitor<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> {
  72     save_ctxt: SaveContext<'l, 'tcx>,
  73     tcx: TyCtxt<'l, 'tcx, 'tcx>,
  74     dumper: &'ll mut JsonDumper<O>,
  75
  76     span: SpanUtils<'l>,
  77
  78     cur_scope: NodeId,
  79
  80     // Set of macro definition (callee) spans, and the set
  81     // of macro use (callsite) spans. We store these to ensure
  82     // we only write one macro def per unique macro definition, and
  83     // one macro use per unique callsite span.
  84     // mac_defs: FxHashSet<Span>,
  85     // macro_calls: FxHashSet<Span>,
  86 }
  87
  88 impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> DumpVisitor<'l, 'tcx, 'll, O> {
  89     pub fn new(
  90         save_ctxt: SaveContext<'l, 'tcx>,
  91         dumper: &'ll mut JsonDumper<O>,
  92     ) -> DumpVisitor<'l, 'tcx, 'll, O> {
  93         let span_utils = SpanUtils::new(&save_ctxt.tcx.sess);
  94         DumpVisitor {
  95             tcx: save_ctxt.tcx,
  96             save_ctxt,
  97             dumper,
  98             span: span_utils,
  99             cur_scope: CRATE_NODE_ID,
 100             // mac_defs: FxHashSet::default(),
 101             // macro_calls: FxHashSet::default(),
 102         }
 103     }
 104
 105     fn nest_scope<F>(&mut self, scope_id: NodeId, f: F)
 106     where
 107         F: FnOnce(&mut DumpVisitor<'l, 'tcx, 'll, O>),
 108     {
 109         let parent_scope = self.cur_scope;
 110         self.cur_scope = scope_id;
 111         f(self);
 112         self.cur_scope = parent_scope;
 113     }
 114
 115     fn nest_tables<F>(&mut self, item_id: NodeId, f: F)
 116     where
 117         F: FnOnce(&mut DumpVisitor<'l, 'tcx, 'll, O>),
 118     {
 119         let item_def_id = self.tcx.hir().local_def_id(item_id);
 120         if self.tcx.has_typeck_tables(item_def_id) {
 121             let tables = self.tcx.typeck_tables_of(item_def_id);
 122             let old_tables = self.save_ctxt.tables;
 123             self.save_ctxt.tables = tables;
 124             f(self);
 125             self.save_ctxt.tables = old_tables;
 126         } else {
 127             f(self);
 128         }
 129     }
 130
 131     fn span_from_span(&self, span: Span) -> SpanData {
 132         self.save_ctxt.span_from_span(span)
 133     }
 134
 135     pub fn dump_crate_info(&mut self, name: &str, krate: &ast::Crate) {
 136         let source_file = self.tcx.sess.local_crate_source_file.as_ref();
 137         let crate_root = source_file.map(|source_file| {
 138             let source_file = Path::new(source_file);
 139             match source_file.file_name() {
 140                 Some(_) => source_file.parent().unwrap().display(),
 141                 None => source_file.display(),
 142             }.to_string()
 143         });
 144
 145         let data = CratePreludeData {
 146             crate_id: GlobalCrateId {
 147                 name: name.into(),
 148                 disambiguator: self.tcx
 149                     .sess
 150                     .local_crate_disambiguator()
 151                     .to_fingerprint()
 152                     .as_value(),
 153             },
 154             crate_root: crate_root.unwrap_or_else(|| "<no source>".to_owned()),
 155             external_crates: self.save_ctxt.get_external_crates(),
 156             span: self.span_from_span(krate.span),
 157         };
 158
 159         self.dumper.crate_prelude(data);
 160     }
 161
 162     pub fn dump_compilation_options(&mut self, input: &Input, crate_name: &str) {
 163         // Apply possible `remap-path-prefix` remapping to the input source file
 164         // (and don't include remapping args anymore)
 165         let (program, arguments) = {
 166             let remap_arg_indices = {
 167                 let mut indices = FxHashSet::default();
 168                 // Args are guaranteed to be valid UTF-8 (checked early)
 169                 for (i, e) in env::args().enumerate() {
 170                     if e.starts_with("--remap-path-prefix=") {
 171                         indices.insert(i);
 172                     } else if e == "--remap-path-prefix" {
 173                         indices.insert(i);
 174                         indices.insert(i + 1);
 175                     }
 176                 }
 177                 indices
 178             };
 179
 180             let mut args = env::args()
 181                 .enumerate()
 182                 .filter(|(i, _)| !remap_arg_indices.contains(i))
 183                 .map(|(_, arg)| {
 184                     match input {
 185                         Input::File(ref path) if path == Path::new(&arg) => {
 186                             let mapped = &self.tcx.sess.local_crate_source_file;
 187                             mapped
 188                                 .as_ref()
 189                                 .unwrap()
 190                                 .to_string_lossy()
 191                                 .into()
 192                         },
 193                         _ => arg,
 194                     }
 195                 });
 196
 197             (args.next().unwrap(), args.collect())
 198         };
 199
 200         let data = CompilationOptions {
 201             directory: self.tcx.sess.working_dir.0.clone(),
 202             program,
 203             arguments,
 204             output: self.save_ctxt.compilation_output(crate_name),
 205         };
 206
 207         self.dumper.compilation_opts(data);
 208     }
 209
 210     fn write_sub_paths(&mut self, path: &ast::Path) {
 211         for seg in &path.segments {
 212             if let Some(data) = self.save_ctxt.get_path_segment_data(seg) {
 213                 self.dumper.dump_ref(data);
 214             }
 215         }
 216     }
 217
 218     // As write_sub_paths, but does not process the last ident in the path (assuming it
 219     // will be processed elsewhere). See note on write_sub_paths about global.
 220     fn write_sub_paths_truncated(&mut self, path: &ast::Path) {
 221         for seg in &path.segments[..path.segments.len() - 1] {
 222             if let Some(data) = self.save_ctxt.get_path_segment_data(seg) {
 223                 self.dumper.dump_ref(data);
 224             }
 225         }
 226     }
 227
 228     fn lookup_def_id(&self, ref_id: NodeId) -> Option<DefId> {
 229         match self.save_ctxt.get_path_def(ref_id) {
 230             HirDef::PrimTy(..) | HirDef::SelfTy(..) | HirDef::Err => None,
 231             def => Some(def.def_id()),
 232         }
 233     }
 234
 235     fn process_formals(&mut self, formals: &'l [ast::Arg], qualname: &str) {
 236         for arg in formals {
 237             self.visit_pat(&arg.pat);
 238             let mut collector = PathCollector::new();
 239             collector.visit_pat(&arg.pat);
 240
 241             for (id, ident, ..) in collector.collected_idents {
 242                 let hir_id = self.tcx.hir().node_to_hir_id(id);
 243                 let typ = match self.save_ctxt.tables.node_id_to_type_opt(hir_id) {
 244                     Some(s) => s.to_string(),
 245                     None => continue,
 246                 };
 247                 if !self.span.filter_generated(ident.span) {
 248                     let id = ::id_from_node_id(id, &self.save_ctxt);
 249                     let span = self.span_from_span(ident.span);
 250
 251                     self.dumper.dump_def(
 252                         &Access {
 253                             public: false,
 254                             reachable: false,
 255                         },
 256                         Def {
 257                             kind: DefKind::Local,
 258                             id,
 259                             span,
 260                             name: ident.to_string(),
 261                             qualname: format!("{}::{}", qualname, ident.to_string()),
 262                             value: typ,
 263                             parent: None,
 264                             children: vec![],
 265                             decl_id: None,
 266                             docs: String::new(),
 267                             sig: None,
 268                             attributes: vec![],
 269                         },
 270                     );
 271                 }
 272             }
 273         }
 274     }
 275
 276     fn process_method(
 277         &mut self,
 278         sig: &'l ast::MethodSig,
 279         body: Option<&'l ast::Block>,
 280         id: ast::NodeId,
 281         ident: ast::Ident,
 282         generics: &'l ast::Generics,
 283         vis: ast::Visibility,
 284         span: Span,
 285     ) {
 286         debug!("process_method: {}:{}", id, ident);
 287
 288         if let Some(mut method_data) = self.save_ctxt.get_method_data(id, ident, span) {
 289             let sig_str = ::make_signature(&sig.decl, &generics);
 290             if body.is_some() {
 291                 self.nest_tables(
 292                     id,
 293                     |v| v.process_formals(&sig.decl.inputs, &method_data.qualname),
 294                 );
 295             }
 296
 297             self.process_generic_params(&generics, &method_data.qualname, id);
 298
 299             method_data.value = sig_str;
 300             method_data.sig = sig::method_signature(id, ident, generics, sig, &self.save_ctxt);
 301             self.dumper.dump_def(&access_from!(self.save_ctxt, vis, id), method_data);
 302         }
 303
 304         // walk arg and return types
 305         for arg in &sig.decl.inputs {
 306             self.visit_ty(&arg.ty);
 307         }
 308
 309         if let ast::FunctionRetTy::Ty(ref ret_ty) = sig.decl.output {
 310             self.visit_ty(ret_ty);
 311         }
 312
 313         // walk the fn body
 314         if let Some(body) = body {
 315             self.nest_tables(id, |v| v.nest_scope(id, |v| v.visit_block(body)));
 316         }
 317     }
 318
 319     fn process_struct_field_def(&mut self, field: &ast::StructField, parent_id: NodeId) {
 320         let field_data = self.save_ctxt.get_field_data(field, parent_id);
 321         if let Some(field_data) = field_data {
 322             self.dumper.dump_def(&access_from!(self.save_ctxt, field), field_data);
 323         }
 324     }
 325
 326     // Dump generic params bindings, then visit_generics
 327     fn process_generic_params(
 328         &mut self,
 329         generics: &'l ast::Generics,
 330         prefix: &str,
 331         id: NodeId,
 332     ) {
 333         for param in &generics.params {
 334             match param.kind {
 335                 ast::GenericParamKind::Lifetime { .. } => {}
 336                 ast::GenericParamKind::Type { .. } => {
 337                     let param_ss = param.ident.span;
 338                     let name = escape(self.span.snippet(param_ss));
 339                     // Append $id to name to make sure each one is unique.
 340                     let qualname = format!("{}::{}${}", prefix, name, id);
 341                     if !self.span.filter_generated(param_ss) {
 342                         let id = ::id_from_node_id(param.id, &self.save_ctxt);
 343                         let span = self.span_from_span(param_ss);
 344
 345                         self.dumper.dump_def(
 346                             &Access {
 347                                 public: false,
 348                                 reachable: false,
 349                             },
 350                             Def {
 351                                 kind: DefKind::Type,
 352                                 id,
 353                                 span,
 354                                 name,
 355                                 qualname,
 356                                 value: String::new(),
 357                                 parent: None,
 358                                 children: vec![],
 359                                 decl_id: None,
 360                                 docs: String::new(),
 361                                 sig: None,
 362                                 attributes: vec![],
 363                             },
 364                         );
 365                     }
 366                 }
 367             }
 368         }
 369         self.visit_generics(generics);
 370     }
 371
 372     fn process_fn(
 373         &mut self,
 374         item: &'l ast::Item,
 375         decl: &'l ast::FnDecl,
 376         ty_params: &'l ast::Generics,
 377         body: &'l ast::Block,
 378     ) {
 379         if let Some(fn_data) = self.save_ctxt.get_item_data(item) {
 380             down_cast_data!(fn_data, DefData, item.span);
 381             self.nest_tables(
 382                 item.id,
 383                 |v| v.process_formals(&decl.inputs, &fn_data.qualname),
 384             );
 385             self.process_generic_params(ty_params, &fn_data.qualname, item.id);
 386             self.dumper.dump_def(&access_from!(self.save_ctxt, item), fn_data);
 387         }
 388
 389         for arg in &decl.inputs {
 390             self.visit_ty(&arg.ty);
 391         }
 392
 393         if let ast::FunctionRetTy::Ty(ref ret_ty) = decl.output {
 394             self.visit_ty(&ret_ty);
 395         }
 396
 397         self.nest_tables(item.id, |v| v.nest_scope(item.id, |v| v.visit_block(&body)));
 398     }
 399
 400     fn process_static_or_const_item(
 401         &mut self,
 402         item: &'l ast::Item,
 403         typ: &'l ast::Ty,
 404         expr: &'l ast::Expr,
 405     ) {
 406         self.nest_tables(item.id, |v| {
 407             if let Some(var_data) = v.save_ctxt.get_item_data(item) {
 408                 down_cast_data!(var_data, DefData, item.span);
 409                 v.dumper.dump_def(&access_from!(v.save_ctxt, item), var_data);
 410             }
 411             v.visit_ty(&typ);
 412             v.visit_expr(expr);
 413         });
 414     }
 415
 416     fn process_assoc_const(
 417         &mut self,
 418         id: ast::NodeId,
 419         ident: ast::Ident,
 420         typ: &'l ast::Ty,
 421         expr: Option<&'l ast::Expr>,
 422         parent_id: DefId,
 423         vis: ast::Visibility,
 424         attrs: &'l [Attribute],
 425     ) {
 426         let qualname = format!("::{}", self.tcx.node_path_str(id));
 427
 428         if !self.span.filter_generated(ident.span) {
 429             let sig = sig::assoc_const_signature(id, ident.name, typ, expr, &self.save_ctxt);
 430             let span = self.span_from_span(ident.span);
 431
 432             self.dumper.dump_def(
 433                 &access_from!(self.save_ctxt, vis, id),
 434                 Def {
 435                     kind: DefKind::Const,
 436                     id: ::id_from_node_id(id, &self.save_ctxt),
 437                     span,
 438                     name: ident.name.to_string(),
 439                     qualname,
 440                     value: ty_to_string(&typ),
 441                     parent: Some(::id_from_def_id(parent_id)),
 442                     children: vec![],
 443                     decl_id: None,
 444                     docs: self.save_ctxt.docs_for_attrs(attrs),
 445                     sig,
 446                     attributes: lower_attributes(attrs.to_owned(), &self.save_ctxt),
 447                 },
 448             );
 449         }
 450
 451         // walk type and init value
 452         self.visit_ty(typ);
 453         if let Some(expr) = expr {
 454             self.visit_expr(expr);
 455         }
 456     }
 457
 458     // FIXME tuple structs should generate tuple-specific data.
 459     fn process_struct(
 460         &mut self,
 461         item: &'l ast::Item,
 462         def: &'l ast::VariantData,
 463         ty_params: &'l ast::Generics,
 464     ) {
 465         debug!("process_struct {:?} {:?}", item, item.span);
 466         let name = item.ident.to_string();
 467         let qualname = format!("::{}", self.tcx.node_path_str(item.id));
 468
 469         let kind = match item.node {
 470             ast::ItemKind::Struct(_, _) => DefKind::Struct,
 471             ast::ItemKind::Union(_, _) => DefKind::Union,
 472             _ => unreachable!(),
 473         };
 474
 475         let (value, fields) = match item.node {
 476             ast::ItemKind::Struct(ast::VariantData::Struct(ref fields, _), _) |
 477             ast::ItemKind::Union(ast::VariantData::Struct(ref fields, _), _) => {
 478                 let include_priv_fields = !self.save_ctxt.config.pub_only;
 479                 let fields_str = fields
 480                     .iter()
 481                     .enumerate()
 482                     .filter_map(|(i, f)| {
 483                         if include_priv_fields || f.vis.node.is_pub() {
 484                             f.ident
 485                                 .map(|i| i.to_string())
 486                                 .or_else(|| Some(i.to_string()))
 487                         } else {
 488                             None
 489                         }
 490                     })
 491                     .collect::<Vec<_>>()
 492                     .join(", ");
 493                 let value = format!("{} {{ {} }}", name, fields_str);
 494                 (
 495                     value,
 496                     fields
 497                         .iter()
 498                         .map(|f| ::id_from_node_id(f.id, &self.save_ctxt))
 499                         .collect(),
 500                 )
 501             }
 502             _ => (String::new(), vec![]),
 503         };
 504
 505         if !self.span.filter_generated(item.ident.span) {
 506             let span = self.span_from_span(item.ident.span);
 507             self.dumper.dump_def(
 508                 &access_from!(self.save_ctxt, item),
 509                 Def {
 510                     kind,
 511                     id: ::id_from_node_id(item.id, &self.save_ctxt),
 512                     span,
 513                     name,
 514                     qualname: qualname.clone(),
 515                     value,
 516                     parent: None,
 517                     children: fields,
 518                     decl_id: None,
 519                     docs: self.save_ctxt.docs_for_attrs(&item.attrs),
 520                     sig: sig::item_signature(item, &self.save_ctxt),
 521                     attributes: lower_attributes(item.attrs.clone(), &self.save_ctxt),
 522                 },
 523             );
 524         }
 525
 526         for field in def.fields() {
 527             self.process_struct_field_def(field, item.id);
 528             self.visit_ty(&field.ty);
 529         }
 530
 531         self.process_generic_params(ty_params, &qualname, item.id);
 532     }
 533
 534     fn process_enum(
 535         &mut self,
 536         item: &'l ast::Item,
 537         enum_definition: &'l ast::EnumDef,
 538         ty_params: &'l ast::Generics,
 539     ) {
 540         let enum_data = self.save_ctxt.get_item_data(item);
 541         let enum_data = match enum_data {
 542             None => return,
 543             Some(data) => data,
 544         };
 545         down_cast_data!(enum_data, DefData, item.span);
 546
 547         let access = access_from!(self.save_ctxt, item);
 548
 549         for variant in &enum_definition.variants {
 550             let name = variant.node.ident.name.to_string();
 551             let qualname = format!("{}::{}", enum_data.qualname, name);
 552             let name_span = variant.node.ident.span;
 553
 554             match variant.node.data {
 555                 ast::VariantData::Struct(ref fields, _) => {
 556                     let fields_str = fields
 557                         .iter()
 558                         .enumerate()
 559                         .map(|(i, f)| {
 560                             f.ident.map(|i| i.to_string()).unwrap_or_else(|| i.to_string())
 561                         })
 562                         .collect::<Vec<_>>()
 563                         .join(", ");
 564                     let value = format!("{}::{} {{ {} }}", enum_data.name, name, fields_str);
 565                     if !self.span.filter_generated(name_span) {
 566                         let span = self.span_from_span(name_span);
 567                         let id = ::id_from_node_id(variant.node.data.id(), &self.save_ctxt);
 568                         let parent = Some(::id_from_node_id(item.id, &self.save_ctxt));
 569
 570                         self.dumper.dump_def(
 571                             &access,
 572                             Def {
 573                                 kind: DefKind::StructVariant,
 574                                 id,
 575                                 span,
 576                                 name,
 577                                 qualname,
 578                                 value,
 579                                 parent,
 580                                 children: vec![],
 581                                 decl_id: None,
 582                                 docs: self.save_ctxt.docs_for_attrs(&variant.node.attrs),
 583                                 sig: sig::variant_signature(variant, &self.save_ctxt),
 584                                 attributes: lower_attributes(
 585                                     variant.node.attrs.clone(),
 586                                     &self.save_ctxt,
 587                                 ),
 588                             },
 589                         );
 590                     }
 591                 }
 592                 ref v => {
 593                     let mut value = format!("{}::{}", enum_data.name, name);
 594                     if let &ast::VariantData::Tuple(ref fields, _) = v {
 595                         value.push('(');
 596                         value.push_str(&fields
 597                             .iter()
 598                             .map(|f| ty_to_string(&f.ty))
 599                             .collect::<Vec<_>>()
 600                             .join(", "));
 601                         value.push(')');
 602                     }
 603                     if !self.span.filter_generated(name_span) {
 604                         let span = self.span_from_span(name_span);
 605                         let id = ::id_from_node_id(variant.node.data.id(), &self.save_ctxt);
 606                         let parent = Some(::id_from_node_id(item.id, &self.save_ctxt));
 607
 608                         self.dumper.dump_def(
 609                             &access,
 610                             Def {
 611                                 kind: DefKind::TupleVariant,
 612                                 id,
 613                                 span,
 614                                 name,
 615                                 qualname,
 616                                 value,
 617                                 parent,
 618                                 children: vec![],
 619                                 decl_id: None,
 620                                 docs: self.save_ctxt.docs_for_attrs(&variant.node.attrs),
 621                                 sig: sig::variant_signature(variant, &self.save_ctxt),
 622                                 attributes: lower_attributes(
 623                                     variant.node.attrs.clone(),
 624                                     &self.save_ctxt,
 625                                 ),
 626                             },
 627                         );
 628                     }
 629                 }
 630             }
 631
 632
 633             for field in variant.node.data.fields() {
 634                 self.process_struct_field_def(field, variant.node.data.id());
 635                 self.visit_ty(&field.ty);
 636             }
 637         }
 638         self.process_generic_params(ty_params, &enum_data.qualname, item.id);
 639         self.dumper.dump_def(&access, enum_data);
 640     }
 641
 642     fn process_impl(
 643         &mut self,
 644         item: &'l ast::Item,
 645         type_parameters: &'l ast::Generics,
 646         trait_ref: &'l Option<ast::TraitRef>,
 647         typ: &'l ast::Ty,
 648         impl_items: &'l [ast::ImplItem],
 649     ) {
 650         if let Some(impl_data) = self.save_ctxt.get_item_data(item) {
 651             if !self.span.filter_generated(item.span) {
 652                 if let super::Data::RelationData(rel, imp) = impl_data {
 653                     self.dumper.dump_relation(rel);
 654                     self.dumper.dump_impl(imp);
 655                 } else {
 656                     span_bug!(item.span, "unexpected data kind: {:?}", impl_data);
 657                 }
 658             }
 659         }
 660         self.visit_ty(&typ);
 661         if let &Some(ref trait_ref) = trait_ref {
 662             self.process_path(trait_ref.ref_id, &trait_ref.path);
 663         }
 664         self.process_generic_params(type_parameters, "", item.id);
 665         for impl_item in impl_items {
 666             let map = &self.tcx.hir();
 667             self.process_impl_item(impl_item, map.local_def_id(item.id));
 668         }
 669     }
 670
 671     fn process_trait(
 672         &mut self,
 673         item: &'l ast::Item,
 674         generics: &'l ast::Generics,
 675         trait_refs: &'l ast::GenericBounds,
 676         methods: &'l [ast::TraitItem],
 677     ) {
 678         let name = item.ident.to_string();
 679         let qualname = format!("::{}", self.tcx.node_path_str(item.id));
 680         let mut val = name.clone();
 681         if !generics.params.is_empty() {
 682             val.push_str(&generic_params_to_string(&generics.params));
 683         }
 684         if !trait_refs.is_empty() {
 685             val.push_str(": ");
 686             val.push_str(&bounds_to_string(trait_refs));
 687         }
 688         if !self.span.filter_generated(item.ident.span) {
 689             let id = ::id_from_node_id(item.id, &self.save_ctxt);
 690             let span = self.span_from_span(item.ident.span);
 691             let children = methods
 692                 .iter()
 693                 .map(|i| ::id_from_node_id(i.id, &self.save_ctxt))
 694                 .collect();
 695             self.dumper.dump_def(
 696                 &access_from!(self.save_ctxt, item),
 697                 Def {
 698                     kind: DefKind::Trait,
 699                     id,
 700                     span,
 701                     name,
 702                     qualname: qualname.clone(),
 703                     value: val,
 704                     parent: None,
 705                     children,
 706                     decl_id: None,
 707                     docs: self.save_ctxt.docs_for_attrs(&item.attrs),
 708                     sig: sig::item_signature(item, &self.save_ctxt),
 709                     attributes: lower_attributes(item.attrs.clone(), &self.save_ctxt),
 710                 },
 711             );
 712         }
 713
 714         // super-traits
 715         for super_bound in trait_refs.iter() {
 716             let trait_ref = match *super_bound {
 717                 ast::GenericBound::Trait(ref trait_ref, _) => trait_ref,
 718                 ast::GenericBound::Outlives(..) => continue,
 719             };
 720
 721             let trait_ref = &trait_ref.trait_ref;
 722             if let Some(id) = self.lookup_def_id(trait_ref.ref_id) {
 723                 let sub_span = trait_ref.path.segments.last().unwrap().ident.span;
 724                 if !self.span.filter_generated(sub_span) {
 725                     let span = self.span_from_span(sub_span);
 726                     self.dumper.dump_ref(Ref {
 727                         kind: RefKind::Type,
 728                         span: span.clone(),
 729                         ref_id: ::id_from_def_id(id),
 730                     });
 731
 732                     self.dumper.dump_relation(Relation {
 733                         kind: RelationKind::SuperTrait,
 734                         span,
 735                         from: ::id_from_def_id(id),
 736                         to: ::id_from_node_id(item.id, &self.save_ctxt),
 737                     });
 738                 }
 739             }
 740         }
 741
 742         // walk generics and methods
 743         self.process_generic_params(generics, &qualname, item.id);
 744         for method in methods {
 745             let map = &self.tcx.hir();
 746             self.process_trait_item(method, map.local_def_id(item.id))
 747         }
 748     }
 749
 750     // `item` is the module in question, represented as an item.
 751     fn process_mod(&mut self, item: &ast::Item) {
 752         if let Some(mod_data) = self.save_ctxt.get_item_data(item) {
 753             down_cast_data!(mod_data, DefData, item.span);
 754             self.dumper.dump_def(&access_from!(self.save_ctxt, item), mod_data);
 755         }
 756     }
 757
 758     fn dump_path_ref(&mut self, id: NodeId, path: &ast::Path) {
 759         let path_data = self.save_ctxt.get_path_data(id, path);
 760         if let Some(path_data) = path_data {
 761             self.dumper.dump_ref(path_data);
 762         }
 763     }
 764
 765     fn process_path(&mut self, id: NodeId, path: &'l ast::Path) {
 766         if self.span.filter_generated(path.span) {
 767             return;
 768         }
 769         self.dump_path_ref(id, path);
 770
 771         // Type arguments
 772         for seg in &path.segments {
 773             if let Some(ref generic_args) = seg.args {
 774                 match **generic_args {
 775                     ast::GenericArgs::AngleBracketed(ref data) => {
 776                         for arg in &data.args {
 777                             match arg {
 778                                 ast::GenericArg::Type(ty) => self.visit_ty(ty),
 779                                 _ => {}
 780                             }
 781                         }
 782                     }
 783                     ast::GenericArgs::Parenthesized(ref data) => {
 784                         for t in &data.inputs {
 785                             self.visit_ty(t);
 786                         }
 787                         if let Some(ref t) = data.output {
 788                             self.visit_ty(t);
 789                         }
 790                     }
 791                 }
 792             }
 793         }
 794
 795         self.write_sub_paths_truncated(path);
 796     }
 797
 798     fn process_struct_lit(
 799         &mut self,
 800         ex: &'l ast::Expr,
 801         path: &'l ast::Path,
 802         fields: &'l [ast::Field],
 803         variant: &'l ty::VariantDef,
 804         base: &'l Option<P<ast::Expr>>,
 805     ) {
 806         if let Some(struct_lit_data) = self.save_ctxt.get_expr_data(ex) {
 807             self.write_sub_paths_truncated(path);
 808             down_cast_data!(struct_lit_data, RefData, ex.span);
 809             if !generated_code(ex.span) {
 810                 self.dumper.dump_ref(struct_lit_data);
 811             }
 812
 813             for field in fields {
 814                 if let Some(field_data) = self.save_ctxt.get_field_ref_data(field, variant) {
 815                     self.dumper.dump_ref(field_data);
 816                 }
 817
 818                 self.visit_expr(&field.expr)
 819             }
 820         }
 821
 822         walk_list!(self, visit_expr, base);
 823     }
 824
 825     fn process_method_call(
 826         &mut self,
 827         ex: &'l ast::Expr,
 828         seg: &'l ast::PathSegment,
 829         args: &'l [P<ast::Expr>],
 830     ) {
 831         debug!("process_method_call {:?} {:?}", ex, ex.span);
 832         if let Some(mcd) = self.save_ctxt.get_expr_data(ex) {
 833             down_cast_data!(mcd, RefData, ex.span);
 834             if !generated_code(ex.span) {
 835                 self.dumper.dump_ref(mcd);
 836             }
 837         }
 838
 839         // Explicit types in the turbo-fish.
 840         if let Some(ref generic_args) = seg.args {
 841             if let ast::GenericArgs::AngleBracketed(ref data) = **generic_args {
 842                 for arg in &data.args {
 843                     match arg {
 844                         ast::GenericArg::Type(ty) => self.visit_ty(ty),
 845                         _ => {}
 846                     }
 847                 }
 848             }
 849         }
 850
 851         // walk receiver and args
 852         walk_list!(self, visit_expr, args);
 853     }
 854
 855     fn process_pat(&mut self, p: &'l ast::Pat) {
 856         match p.node {
 857             PatKind::Struct(ref _path, ref fields, _) => {
 858                 // FIXME do something with _path?
 859                 let hir_id = self.tcx.hir().node_to_hir_id(p.id);
 860                 let adt = match self.save_ctxt.tables.node_id_to_type_opt(hir_id) {
 861                     Some(ty) => ty.ty_adt_def().unwrap(),
 862                     None => {
 863                         visit::walk_pat(self, p);
 864                         return;
 865                     }
 866                 };
 867                 let variant = adt.variant_of_def(self.save_ctxt.get_path_def(p.id));
 868
 869                 for &Spanned { node: ref field, .. } in fields {
 870                     if let Some(index) = self.tcx.find_field_index(field.ident, variant) {
 871                         if !self.span.filter_generated(field.ident.span) {
 872                             let span = self.span_from_span(field.ident.span);
 873                             self.dumper.dump_ref(Ref {
 874                                 kind: RefKind::Variable,
 875                                 span,
 876                                 ref_id: ::id_from_def_id(variant.fields[index].did),
 877                             });
 878                         }
 879                     }
 880                     self.visit_pat(&field.pat);
 881                 }
 882             }
 883             _ => visit::walk_pat(self, p),
 884         }
 885     }
 886
 887     fn process_var_decl_multi(&mut self, pats: &'l [P<ast::Pat>]) {
 888         let mut collector = PathCollector::new();
 889         for pattern in pats {
 890             // collect paths from the arm's patterns
 891             collector.visit_pat(&pattern);
 892             self.visit_pat(&pattern);
 893         }
 894
 895         // process collected paths
 896         for (id, ident, immut) in collector.collected_idents {
 897             match self.save_ctxt.get_path_def(id) {
 898                 HirDef::Local(id) => {
 899                     let mut value = if immut == ast::Mutability::Immutable {
 900                         self.span.snippet(ident.span)
 901                     } else {
 902                         "<mutable>".to_owned()
 903                     };
 904                     let hir_id = self.tcx.hir().node_to_hir_id(id);
 905                     let typ = self.save_ctxt
 906                         .tables
 907                         .node_id_to_type_opt(hir_id)
 908                         .map(|t| t.to_string())
 909                         .unwrap_or_default();
 910                     value.push_str(": ");
 911                     value.push_str(&typ);
 912
 913                     if !self.span.filter_generated(ident.span) {
 914                         let qualname = format!("{}${}", ident.to_string(), id);
 915                         let id = ::id_from_node_id(id, &self.save_ctxt);
 916                         let span = self.span_from_span(ident.span);
 917
 918                         self.dumper.dump_def(
 919                             &Access {
 920                                 public: false,
 921                                 reachable: false,
 922                             },
 923                             Def {
 924                                 kind: DefKind::Local,
 925                                 id,
 926                                 span,
 927                                 name: ident.to_string(),
 928                                 qualname,
 929                                 value: typ,
 930                                 parent: None,
 931                                 children: vec![],
 932                                 decl_id: None,
 933                                 docs: String::new(),
 934                                 sig: None,
 935                                 attributes: vec![],
 936                             },
 937                         );
 938                     }
 939                 }
 940                 HirDef::StructCtor(..) |
 941                 HirDef::VariantCtor(..) |
 942                 HirDef::Const(..) |
 943                 HirDef::AssociatedConst(..) |
 944                 HirDef::Struct(..) |
 945                 HirDef::Variant(..) |
 946                 HirDef::TyAlias(..) |
 947                 HirDef::AssociatedTy(..) |
 948                 HirDef::SelfTy(..) => {
 949                     self.dump_path_ref(id, &ast::Path::from_ident(ident));
 950                 }
 951                 def => error!(
 952                     "unexpected definition kind when processing collected idents: {:?}",
 953                     def
 954                 ),
 955             }
 956         }
 957
 958         for (id, ref path) in collector.collected_paths {
 959             self.process_path(id, path);
 960         }
 961     }
 962
 963     fn process_var_decl(&mut self, p: &'l ast::Pat, value: String) {
 964         // The local could declare multiple new vars, we must walk the
 965         // pattern and collect them all.
 966         let mut collector = PathCollector::new();
 967         collector.visit_pat(&p);
 968         self.visit_pat(&p);
 969
 970         for (id, ident, immut) in collector.collected_idents {
 971             let mut value = match immut {
 972                 ast::Mutability::Immutable => value.to_string(),
 973                 _ => String::new(),
 974             };
 975             let hir_id = self.tcx.hir().node_to_hir_id(id);
 976             let typ = match self.save_ctxt.tables.node_id_to_type_opt(hir_id) {
 977                 Some(typ) => {
 978                     let typ = typ.to_string();
 979                     if !value.is_empty() {
 980                         value.push_str(": ");
 981                     }
 982                     value.push_str(&typ);
 983                     typ
 984                 }
 985                 None => String::new(),
 986             };
 987
 988             // Rust uses the id of the pattern for var lookups, so we'll use it too.
 989             if !self.span.filter_generated(ident.span) {
 990                 let qualname = format!("{}${}", ident.to_string(), id);
 991                 let id = ::id_from_node_id(id, &self.save_ctxt);
 992                 let span = self.span_from_span(ident.span);
 993
 994                 self.dumper.dump_def(
 995                     &Access {
 996                         public: false,
 997                         reachable: false,
 998                     },
 999                     Def {
1000                         kind: DefKind::Local,
1001                         id,
1002                         span,
1003                         name: ident.to_string(),
1004                         qualname,
1005                         value: typ,
1006                         parent: None,
1007                         children: vec![],
1008                         decl_id: None,
1009                         docs: String::new(),
1010                         sig: None,
1011                         attributes: vec![],
1012                     },
1013                 );
1014             }
1015         }
1016     }
1017
1018     /// Extract macro use and definition information from the AST node defined
1019     /// by the given NodeId, using the expansion information from the node's
1020     /// span.
1021     ///
1022     /// If the span is not macro-generated, do nothing, else use callee and
1023     /// callsite spans to record macro definition and use data, using the
1024     /// mac_uses and mac_defs sets to prevent multiples.
1025     fn process_macro_use(&mut self, _span: Span) {
1026         // FIXME if we're not dumping the defs (see below), there is no point
1027         // dumping refs either.
1028         // let source_span = span.source_callsite();
1029         // if !self.macro_calls.insert(source_span) {
1030         //     return;
1031         // }
1032
1033         // let data = match self.save_ctxt.get_macro_use_data(span) {
1034         //     None => return,
1035         //     Some(data) => data,
1036         // };
1037
1038         // self.dumper.macro_use(data);
1039
1040         // FIXME write the macro def
1041         // let mut hasher = DefaultHasher::new();
1042         // data.callee_span.hash(&mut hasher);
1043         // let hash = hasher.finish();
1044         // let qualname = format!("{}::{}", data.name, hash);
1045         // Don't write macro definition for imported macros
1046         // if !self.mac_defs.contains(&data.callee_span)
1047         //     && !data.imported {
1048         //     self.mac_defs.insert(data.callee_span);
1049         //     if let Some(sub_span) = self.span.span_for_macro_def_name(data.callee_span) {
1050         //         self.dumper.macro_data(MacroData {
1051         //             span: sub_span,
1052         //             name: data.name.clone(),
1053         //             qualname: qualname.clone(),
1054         //             // FIXME where do macro docs come from?
1055         //             docs: String::new(),
1056         //         }.lower(self.tcx));
1057         //     }
1058         // }
1059     }
1060
1061     fn process_trait_item(&mut self, trait_item: &'l ast::TraitItem, trait_id: DefId) {
1062         self.process_macro_use(trait_item.span);
1063         let vis_span = trait_item.span.shrink_to_lo();
1064         match trait_item.node {
1065             ast::TraitItemKind::Const(ref ty, ref expr) => {
1066                 self.process_assoc_const(
1067                     trait_item.id,
1068                     trait_item.ident,
1069                     &ty,
1070                     expr.as_ref().map(|e| &**e),
1071                     trait_id,
1072                     respan(vis_span, ast::VisibilityKind::Public),
1073                     &trait_item.attrs,
1074                 );
1075             }
1076             ast::TraitItemKind::Method(ref sig, ref body) => {
1077                 self.process_method(
1078                     sig,
1079                     body.as_ref().map(|x| &**x),
1080                     trait_item.id,
1081                     trait_item.ident,
1082                     &trait_item.generics,
1083                     respan(vis_span, ast::VisibilityKind::Public),
1084                     trait_item.span,
1085                 );
1086             }
1087             ast::TraitItemKind::Type(ref bounds, ref default_ty) => {
1088                 // FIXME do something with _bounds (for type refs)
1089                 let name = trait_item.ident.name.to_string();
1090                 let qualname = format!("::{}", self.tcx.node_path_str(trait_item.id));
1091
1092                 if !self.span.filter_generated(trait_item.ident.span) {
1093                     let span = self.span_from_span(trait_item.ident.span);
1094                     let id = ::id_from_node_id(trait_item.id, &self.save_ctxt);
1095
1096                     self.dumper.dump_def(
1097                         &Access {
1098                             public: true,
1099                             reachable: true,
1100                         },
1101                         Def {
1102                             kind: DefKind::Type,
1103                             id,
1104                             span,
1105                             name,
1106                             qualname,
1107                             value: self.span.snippet(trait_item.span),
1108                             parent: Some(::id_from_def_id(trait_id)),
1109                             children: vec![],
1110                             decl_id: None,
1111                             docs: self.save_ctxt.docs_for_attrs(&trait_item.attrs),
1112                             sig: sig::assoc_type_signature(
1113                                 trait_item.id,
1114                                 trait_item.ident,
1115                                 Some(bounds),
1116                                 default_ty.as_ref().map(|ty| &**ty),
1117                                 &self.save_ctxt,
1118                             ),
1119                             attributes: lower_attributes(trait_item.attrs.clone(), &self.save_ctxt),
1120                         },
1121                     );
1122                 }
1123
1124                 if let &Some(ref default_ty) = default_ty {
1125                     self.visit_ty(default_ty)
1126                 }
1127             }
1128             ast::TraitItemKind::Macro(_) => {}
1129         }
1130     }
1131
1132     fn process_impl_item(&mut self, impl_item: &'l ast::ImplItem, impl_id: DefId) {
1133         self.process_macro_use(impl_item.span);
1134         match impl_item.node {
1135             ast::ImplItemKind::Const(ref ty, ref expr) => {
1136                 self.process_assoc_const(
1137                     impl_item.id,
1138                     impl_item.ident,
1139                     &ty,
1140                     Some(expr),
1141                     impl_id,
1142                     impl_item.vis.clone(),
1143                     &impl_item.attrs,
1144                 );
1145             }
1146             ast::ImplItemKind::Method(ref sig, ref body) => {
1147                 self.process_method(
1148                     sig,
1149                     Some(body),
1150                     impl_item.id,
1151                     impl_item.ident,
1152                     &impl_item.generics,
1153                     impl_item.vis.clone(),
1154                     impl_item.span,
1155                 );
1156             }
1157             ast::ImplItemKind::Type(ref ty) => {
1158                 // FIXME uses of the assoc type should ideally point to this
1159                 // 'def' and the name here should be a ref to the def in the
1160                 // trait.
1161                 self.visit_ty(ty)
1162             }
1163             ast::ImplItemKind::Existential(ref bounds) => {
1164                 // FIXME uses of the assoc type should ideally point to this
1165                 // 'def' and the name here should be a ref to the def in the
1166                 // trait.
1167                 for bound in bounds.iter() {
1168                     if let ast::GenericBound::Trait(trait_ref, _) = bound {
1169                         self.process_path(trait_ref.trait_ref.ref_id, &trait_ref.trait_ref.path)
1170                     }
1171                 }
1172             }
1173             ast::ImplItemKind::Macro(_) => {}
1174         }
1175     }
1176
1177     /// Dumps imports in a use tree recursively.
1178     ///
1179     /// A use tree is an import that may contain nested braces (RFC 2128). The `use_tree` parameter
1180     /// is the current use tree under scrutiny, while `id` and `prefix` are its corresponding node
1181     /// id and path. `root_item` is the topmost use tree in the hierarchy.
1182     ///
1183     /// If `use_tree` is a simple or glob import, it is dumped into the analysis data. Otherwise,
1184     /// each child use tree is dumped recursively.
1185     fn process_use_tree(&mut self,
1186                          use_tree: &'l ast::UseTree,
1187                          id: NodeId,
1188                          root_item: &'l ast::Item,
1189                          prefix: &ast::Path) {
1190         let path = &use_tree.prefix;
1191
1192         // The access is calculated using the current tree ID, but with the root tree's visibility
1193         // (since nested trees don't have their own visibility).
1194         let access = access_from!(self.save_ctxt, root_item.vis, id);
1195
1196         // The parent def id of a given use tree is always the enclosing item.
1197         let parent = self.save_ctxt.tcx.hir().opt_local_def_id(id)
1198             .and_then(|id| self.save_ctxt.tcx.parent_def_id(id))
1199             .map(::id_from_def_id);
1200
1201         match use_tree.kind {
1202             ast::UseTreeKind::Simple(alias, ..) => {
1203                 let ident = use_tree.ident();
1204                 let path = ast::Path {
1205                     segments: prefix.segments
1206                         .iter()
1207                         .chain(path.segments.iter())
1208                         .cloned()
1209                         .collect(),
1210                     span: path.span,
1211                 };
1212
1213                 let sub_span = path.segments.last().unwrap().ident.span;
1214                 if !self.span.filter_generated(sub_span) {
1215                     let ref_id = self.lookup_def_id(id).map(|id| ::id_from_def_id(id));
1216                     let alias_span = alias.map(|i| self.span_from_span(i.span));
1217                     let span = self.span_from_span(sub_span);
1218                     self.dumper.import(&access, Import {
1219                         kind: ImportKind::Use,
1220                         ref_id,
1221                         span,
1222                         alias_span,
1223                         name: ident.to_string(),
1224                         value: String::new(),
1225                         parent,
1226                     });
1227                     self.write_sub_paths_truncated(&path);
1228                 }
1229             }
1230             ast::UseTreeKind::Glob => {
1231                 let path = ast::Path {
1232                     segments: prefix.segments
1233                         .iter()
1234                         .chain(path.segments.iter())
1235                         .cloned()
1236                         .collect(),
1237                     span: path.span,
1238                 };
1239
1240                 // Make a comma-separated list of names of imported modules.
1241                 let def_id = self.tcx.hir().local_def_id(id);
1242                 let names = self.tcx.names_imported_by_glob_use(def_id);
1243                 let names: Vec<_> = names.iter().map(|n| n.to_string()).collect();
1244
1245                 // Otherwise it's a span with wrong macro expansion info, which
1246                 // we don't want to track anyway, since it's probably macro-internal `use`
1247                 if let Some(sub_span) =
1248                     self.span.sub_span_of_token(use_tree.span, token::BinOp(token::Star))
1249                 {
1250                     if !self.span.filter_generated(use_tree.span) {
1251                         let span = self.span_from_span(sub_span);
1252
1253                         self.dumper.import(&access, Import {
1254                             kind: ImportKind::GlobUse,
1255                             ref_id: None,
1256                             span,
1257                             alias_span: None,
1258                             name: "*".to_owned(),
1259                             value: names.join(", "),
1260                             parent,
1261                         });
1262                         self.write_sub_paths(&path);
1263                     }
1264                 }
1265             }
1266             ast::UseTreeKind::Nested(ref nested_items) => {
1267                 let prefix = ast::Path {
1268                     segments: prefix.segments
1269                         .iter()
1270                         .chain(path.segments.iter())
1271                         .cloned()
1272                         .collect(),
1273                     span: path.span,
1274                 };
1275                 for &(ref tree, id) in nested_items {
1276                     self.process_use_tree(tree, id, root_item, &prefix);
1277                 }
1278             }
1279         }
1280     }
1281
1282     fn process_bounds(&mut self, bounds: &'l ast::GenericBounds) {
1283         for bound in bounds {
1284             if let ast::GenericBound::Trait(ref trait_ref, _) = *bound {
1285                 self.process_path(trait_ref.trait_ref.ref_id, &trait_ref.trait_ref.path)
1286             }
1287         }
1288     }
1289 }
1290
1291 impl<'l, 'tcx: 'l, 'll, O: DumpOutput + 'll> Visitor<'l> for DumpVisitor<'l, 'tcx, 'll, O> {
1292     fn visit_mod(&mut self, m: &'l ast::Mod, span: Span, attrs: &[ast::Attribute], id: NodeId) {
1293         // Since we handle explicit modules ourselves in visit_item, this should
1294         // only get called for the root module of a crate.
1295         assert_eq!(id, ast::CRATE_NODE_ID);
1296
1297         let qualname = format!("::{}", self.tcx.node_path_str(id));
1298
1299         let cm = self.tcx.sess.source_map();
1300         let filename = cm.span_to_filename(span);
1301         let data_id = ::id_from_node_id(id, &self.save_ctxt);
1302         let children = m.items
1303             .iter()
1304             .map(|i| ::id_from_node_id(i.id, &self.save_ctxt))
1305             .collect();
1306         let span = self.span_from_span(span);
1307
1308         self.dumper.dump_def(
1309             &Access {
1310                 public: true,
1311                 reachable: true,
1312             },
1313             Def {
1314                 kind: DefKind::Mod,
1315                 id: data_id,
1316                 name: String::new(),
1317                 qualname,
1318                 span,
1319                 value: filename.to_string(),
1320                 children,
1321                 parent: None,
1322                 decl_id: None,
1323                 docs: self.save_ctxt.docs_for_attrs(attrs),
1324                 sig: None,
1325                 attributes: lower_attributes(attrs.to_owned(), &self.save_ctxt),
1326             },
1327         );
1328         self.nest_scope(id, |v| visit::walk_mod(v, m));
1329     }
1330
1331     fn visit_item(&mut self, item: &'l ast::Item) {
1332         use syntax::ast::ItemKind::*;
1333         self.process_macro_use(item.span);
1334         match item.node {
1335             Use(ref use_tree) => {
1336                 let prefix = ast::Path {
1337                     segments: vec![],
1338                     span: DUMMY_SP,
1339                 };
1340                 self.process_use_tree(use_tree, item.id, item, &prefix);
1341             }
1342             ExternCrate(_) => {
1343                 let name_span = item.ident.span;
1344                 if !self.span.filter_generated(name_span) {
1345                     let span = self.span_from_span(name_span);
1346                     let parent = self.save_ctxt.tcx.hir().opt_local_def_id(item.id)
1347                         .and_then(|id| self.save_ctxt.tcx.parent_def_id(id))
1348                         .map(::id_from_def_id);
1349                     self.dumper.import(
1350                         &Access {
1351                             public: false,
1352                             reachable: false,
1353                         },
1354                         Import {
1355                             kind: ImportKind::ExternCrate,
1356                             ref_id: None,
1357                             span,
1358                             alias_span: None,
1359                             name: item.ident.to_string(),
1360                             value: String::new(),
1361                             parent,
1362                         },
1363                     );
1364                 }
1365             }
1366             Fn(ref decl, .., ref ty_params, ref body) => {
1367                 self.process_fn(item, &decl, ty_params, &body)
1368             }
1369             Static(ref typ, _, ref expr) => self.process_static_or_const_item(item, typ, expr),
1370             Const(ref typ, ref expr) => self.process_static_or_const_item(item, &typ, &expr),
1371             Struct(ref def, ref ty_params) | Union(ref def, ref ty_params) => {
1372                 self.process_struct(item, def, ty_params)
1373             }
1374             Enum(ref def, ref ty_params) => self.process_enum(item, def, ty_params),
1375             Impl(.., ref ty_params, ref trait_ref, ref typ, ref impl_items) => {
1376                 self.process_impl(item, ty_params, trait_ref, &typ, impl_items)
1377             }
1378             Trait(_, _, ref generics, ref trait_refs, ref methods) => {
1379                 self.process_trait(item, generics, trait_refs, methods)
1380             }
1381             Mod(ref m) => {
1382                 self.process_mod(item);
1383                 self.nest_scope(item.id, |v| visit::walk_mod(v, m));
1384             }
1385             Ty(ref ty, ref ty_params) => {
1386                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
1387                 let value = ty_to_string(&ty);
1388                 if !self.span.filter_generated(item.ident.span) {
1389                     let span = self.span_from_span(item.ident.span);
1390                     let id = ::id_from_node_id(item.id, &self.save_ctxt);
1391
1392                     self.dumper.dump_def(
1393                         &access_from!(self.save_ctxt, item),
1394                         Def {
1395                             kind: DefKind::Type,
1396                             id,
1397                             span,
1398                             name: item.ident.to_string(),
1399                             qualname: qualname.clone(),
1400                             value,
1401                             parent: None,
1402                             children: vec![],
1403                             decl_id: None,
1404                             docs: self.save_ctxt.docs_for_attrs(&item.attrs),
1405                             sig: sig::item_signature(item, &self.save_ctxt),
1406                             attributes: lower_attributes(item.attrs.clone(), &self.save_ctxt),
1407                         },
1408                     );
1409                 }
1410
1411                 self.visit_ty(&ty);
1412                 self.process_generic_params(ty_params, &qualname, item.id);
1413             }
1414             Existential(ref _bounds, ref ty_params) => {
1415                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
1416                 // FIXME do something with _bounds
1417                 let value = String::new();
1418                 if !self.span.filter_generated(item.ident.span) {
1419                     let span = self.span_from_span(item.ident.span);
1420                     let id = ::id_from_node_id(item.id, &self.save_ctxt);
1421
1422                     self.dumper.dump_def(
1423                         &access_from!(self.save_ctxt, item),
1424                         Def {
1425                             kind: DefKind::Type,
1426                             id,
1427                             span,
1428                             name: item.ident.to_string(),
1429                             qualname: qualname.clone(),
1430                             value,
1431                             parent: None,
1432                             children: vec![],
1433                             decl_id: None,
1434                             docs: self.save_ctxt.docs_for_attrs(&item.attrs),
1435                             sig: sig::item_signature(item, &self.save_ctxt),
1436                             attributes: lower_attributes(item.attrs.clone(), &self.save_ctxt),
1437                         },
1438                     );
1439                 }
1440
1441                 self.process_generic_params(ty_params, &qualname, item.id);
1442             }
1443             Mac(_) => (),
1444             _ => visit::walk_item(self, item),
1445         }
1446     }
1447
1448     fn visit_generics(&mut self, generics: &'l ast::Generics) {
1449         for param in &generics.params {
1450             if let ast::GenericParamKind::Type { ref default, .. } = param.kind {
1451                 self.process_bounds(&param.bounds);
1452                 if let Some(ref ty) = default {
1453                     self.visit_ty(&ty);
1454                 }
1455             }
1456         }
1457         for pred in &generics.where_clause.predicates {
1458             if let ast::WherePredicate::BoundPredicate(ref wbp) = *pred {
1459                 self.process_bounds(&wbp.bounds);
1460                 self.visit_ty(&wbp.bounded_ty);
1461             }
1462         }
1463     }
1464
1465     fn visit_ty(&mut self, t: &'l ast::Ty) {
1466         self.process_macro_use(t.span);
1467         match t.node {
1468             ast::TyKind::Path(_, ref path) => {
1469                 if generated_code(t.span) {
1470                     return;
1471                 }
1472
1473                 if let Some(id) = self.lookup_def_id(t.id) {
1474                     let sub_span = path.segments.last().unwrap().ident.span;
1475                     let span = self.span_from_span(sub_span);
1476                     self.dumper.dump_ref(Ref {
1477                         kind: RefKind::Type,
1478                         span,
1479                         ref_id: ::id_from_def_id(id),
1480                     });
1481                 }
1482
1483                 self.write_sub_paths_truncated(path);
1484                 visit::walk_path(self, path);
1485             }
1486             ast::TyKind::Array(ref element, ref length) => {
1487                 self.visit_ty(element);
1488                 self.nest_tables(length.id, |v| v.visit_expr(&length.value));
1489             }
1490             _ => visit::walk_ty(self, t),
1491         }
1492     }
1493
1494     fn visit_expr(&mut self, ex: &'l ast::Expr) {
1495         debug!("visit_expr {:?}", ex.node);
1496         self.process_macro_use(ex.span);
1497         match ex.node {
1498             ast::ExprKind::Struct(ref path, ref fields, ref base) => {
1499                 let hir_expr = self.save_ctxt.tcx.hir().expect_expr(ex.id);
1500                 let adt = match self.save_ctxt.tables.expr_ty_opt(&hir_expr) {
1501                     Some(ty) if ty.ty_adt_def().is_some() => ty.ty_adt_def().unwrap(),
1502                     _ => {
1503                         visit::walk_expr(self, ex);
1504                         return;
1505                     }
1506                 };
1507                 let def = self.save_ctxt.get_path_def(hir_expr.id);
1508                 self.process_struct_lit(ex, path, fields, adt.variant_of_def(def), base)
1509             }
1510             ast::ExprKind::MethodCall(ref seg, ref args) => self.process_method_call(ex, seg, args),
1511             ast::ExprKind::Field(ref sub_ex, _) => {
1512                 self.visit_expr(&sub_ex);
1513
1514                 if let Some(field_data) = self.save_ctxt.get_expr_data(ex) {
1515                     down_cast_data!(field_data, RefData, ex.span);
1516                     if !generated_code(ex.span) {
1517                         self.dumper.dump_ref(field_data);
1518                     }
1519                 }
1520             }
1521             ast::ExprKind::Closure(_, _, _, ref decl, ref body, _fn_decl_span) => {
1522                 let id = format!("${}", ex.id);
1523
1524                 // walk arg and return types
1525                 for arg in &decl.inputs {
1526                     self.visit_ty(&arg.ty);
1527                 }
1528
1529                 if let ast::FunctionRetTy::Ty(ref ret_ty) = decl.output {
1530                     self.visit_ty(&ret_ty);
1531                 }
1532
1533                 // walk the body
1534                 self.nest_tables(ex.id, |v| {
1535                     v.process_formals(&decl.inputs, &id);
1536                     v.nest_scope(ex.id, |v| v.visit_expr(body))
1537                 });
1538             }
1539             ast::ExprKind::ForLoop(ref pattern, ref subexpression, ref block, _) => {
1540                 let value = self.span.snippet(subexpression.span);
1541                 self.process_var_decl(pattern, value);
1542                 debug!("for loop, walk sub-expr: {:?}", subexpression.node);
1543                 self.visit_expr(subexpression);
1544                 visit::walk_block(self, block);
1545             }
1546             ast::ExprKind::WhileLet(ref pats, ref subexpression, ref block, _) => {
1547                 self.process_var_decl_multi(pats);
1548                 debug!("for loop, walk sub-expr: {:?}", subexpression.node);
1549                 self.visit_expr(subexpression);
1550                 visit::walk_block(self, block);
1551             }
1552             ast::ExprKind::IfLet(ref pats, ref subexpression, ref block, ref opt_else) => {
1553                 self.process_var_decl_multi(pats);
1554                 self.visit_expr(subexpression);
1555                 visit::walk_block(self, block);
1556                 opt_else.as_ref().map(|el| self.visit_expr(el));
1557             }
1558             ast::ExprKind::Repeat(ref element, ref count) => {
1559                 self.visit_expr(element);
1560                 self.nest_tables(count.id, |v| v.visit_expr(&count.value));
1561             }
1562             // In particular, we take this branch for call and path expressions,
1563             // where we'll index the idents involved just by continuing to walk.
1564             _ => visit::walk_expr(self, ex),
1565         }
1566     }
1567
1568     fn visit_mac(&mut self, mac: &'l ast::Mac) {
1569         // These shouldn't exist in the AST at this point, log a span bug.
1570         span_bug!(
1571             mac.span,
1572             "macro invocation should have been expanded out of AST"
1573         );
1574     }
1575
1576     fn visit_pat(&mut self, p: &'l ast::Pat) {
1577         self.process_macro_use(p.span);
1578         self.process_pat(p);
1579     }
1580
1581     fn visit_arm(&mut self, arm: &'l ast::Arm) {
1582         self.process_var_decl_multi(&arm.pats);
1583         match arm.guard {
1584             Some(ast::Guard::If(ref expr)) => self.visit_expr(expr),
1585             _ => {}
1586         }
1587         self.visit_expr(&arm.body);
1588     }
1589
1590     fn visit_path(&mut self, p: &'l ast::Path, id: NodeId) {
1591         self.process_path(id, p);
1592     }
1593
1594     fn visit_stmt(&mut self, s: &'l ast::Stmt) {
1595         self.process_macro_use(s.span);
1596         visit::walk_stmt(self, s)
1597     }
1598
1599     fn visit_local(&mut self, l: &'l ast::Local) {
1600         self.process_macro_use(l.span);
1601         let value = l.init
1602             .as_ref()
1603             .map(|i| self.span.snippet(i.span))
1604             .unwrap_or_default();
1605         self.process_var_decl(&l.pat, value);
1606
1607         // Just walk the initialiser and type (don't want to walk the pattern again).
1608         walk_list!(self, visit_ty, &l.ty);
1609         walk_list!(self, visit_expr, &l.init);
1610     }
1611
1612     fn visit_foreign_item(&mut self, item: &'l ast::ForeignItem) {
1613         let access = access_from!(self.save_ctxt, item);
1614
1615         match item.node {
1616             ast::ForeignItemKind::Fn(ref decl, ref generics) => {
1617                 if let Some(fn_data) = self.save_ctxt.get_extern_item_data(item) {
1618                     down_cast_data!(fn_data, DefData, item.span);
1619
1620                     self.process_generic_params(generics, &fn_data.qualname, item.id);
1621                     self.dumper.dump_def(&access, fn_data);
1622                 }
1623
1624                 for arg in &decl.inputs {
1625                     self.visit_ty(&arg.ty);
1626                 }
1627
1628                 if let ast::FunctionRetTy::Ty(ref ret_ty) = decl.output {
1629                     self.visit_ty(&ret_ty);
1630                 }
1631             }
1632             ast::ForeignItemKind::Static(ref ty, _) => {
1633                 if let Some(var_data) = self.save_ctxt.get_extern_item_data(item) {
1634                     down_cast_data!(var_data, DefData, item.span);
1635                     self.dumper.dump_def(&access, var_data);
1636                 }
1637
1638                 self.visit_ty(ty);
1639             }
1640             ast::ForeignItemKind::Ty => {
1641                 if let Some(var_data) = self.save_ctxt.get_extern_item_data(item) {
1642                     down_cast_data!(var_data, DefData, item.span);
1643                     self.dumper.dump_def(&access, var_data);
1644                 }
1645             }
1646             ast::ForeignItemKind::Macro(..) => {}
1647         }
1648     }
1649 }