src/librustc_save_analysis/lib.rs

   1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/")]
   2 #![feature(nll)]
   3 #![feature(or_patterns)]
   4 #![recursion_limit = "256"]
   5
   6 mod dump_visitor;
   7 mod dumper;
   8 #[macro_use]
   9 mod span_utils;
  10 mod sig;
  11
  12 use rustc_ast as ast;
  13 use rustc_ast::util::comments::beautify_doc_string;
  14 use rustc_ast_pretty::pprust::attribute_to_string;
  15 use rustc_hir as hir;
  16 use rustc_hir::def::{DefKind as HirDefKind, Res};
  17 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
  18 use rustc_hir::intravisit::{self, Visitor};
  19 use rustc_hir::Node;
  20 use rustc_hir_pretty::{enum_def_to_string, fn_to_string, ty_to_string};
  21 use rustc_middle::hir::map::Map;
  22 use rustc_middle::middle::cstore::ExternCrate;
  23 use rustc_middle::middle::privacy::AccessLevels;
  24 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
  25 use rustc_middle::{bug, span_bug};
  26 use rustc_session::config::{CrateType, Input, OutputType};
  27 use rustc_session::output::{filename_for_metadata, out_filename};
  28 use rustc_span::source_map::Spanned;
  29 use rustc_span::symbol::Ident;
  30 use rustc_span::*;
  31
  32 use std::cell::Cell;
  33 use std::default::Default;
  34 use std::env;
  35 use std::fs::File;
  36 use std::io::BufWriter;
  37 use std::path::{Path, PathBuf};
  38
  39 use dump_visitor::DumpVisitor;
  40 use span_utils::SpanUtils;
  41
  42 use rls_data::config::Config;
  43 use rls_data::{
  44     Analysis, Def, DefKind, ExternalCrateData, GlobalCrateId, Impl, ImplKind, MacroRef, Ref,
  45     RefKind, Relation, RelationKind, SpanData,
  46 };
  47
  48 use tracing::{debug, error, info};
  49
  50 pub struct SaveContext<'tcx> {
  51     tcx: TyCtxt<'tcx>,
  52     maybe_typeck_results: Option<&'tcx ty::TypeckResults<'tcx>>,
  53     access_levels: &'tcx AccessLevels,
  54     span_utils: SpanUtils<'tcx>,
  55     config: Config,
  56     impl_counter: Cell<u32>,
  57 }
  58
  59 #[derive(Debug)]
  60 pub enum Data {
  61     RefData(Ref),
  62     DefData(Def),
  63     RelationData(Relation, Impl),
  64 }
  65
  66 impl<'tcx> SaveContext<'tcx> {
  67     /// Gets the type-checking results for the current body.
  68     /// As this will ICE if called outside bodies, only call when working with
  69     /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
  70     #[track_caller]
  71     fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
  72         self.maybe_typeck_results.expect("`SaveContext::typeck_results` called outside of body")
  73     }
  74
  75     fn span_from_span(&self, span: Span) -> SpanData {
  76         use rls_span::{Column, Row};
  77
  78         let sm = self.tcx.sess.source_map();
  79         let start = sm.lookup_char_pos(span.lo());
  80         let end = sm.lookup_char_pos(span.hi());
  81
  82         SpanData {
  83             file_name: start.file.name.to_string().into(),
  84             byte_start: span.lo().0,
  85             byte_end: span.hi().0,
  86             line_start: Row::new_one_indexed(start.line as u32),
  87             line_end: Row::new_one_indexed(end.line as u32),
  88             column_start: Column::new_one_indexed(start.col.0 as u32 + 1),
  89             column_end: Column::new_one_indexed(end.col.0 as u32 + 1),
  90         }
  91     }
  92
  93     // Returns path to the compilation output (e.g., libfoo-12345678.rmeta)
  94     pub fn compilation_output(&self, crate_name: &str) -> PathBuf {
  95         let sess = &self.tcx.sess;
  96         // Save-analysis is emitted per whole session, not per each crate type
  97         let crate_type = sess.crate_types()[0];
  98         let outputs = &*self.tcx.output_filenames(LOCAL_CRATE);
  99
 100         if outputs.outputs.contains_key(&OutputType::Metadata) {
 101             filename_for_metadata(sess, crate_name, outputs)
 102         } else if outputs.outputs.should_codegen() {
 103             out_filename(sess, crate_type, outputs, crate_name)
 104         } else {
 105             // Otherwise it's only a DepInfo, in which case we return early and
 106             // not even reach the analysis stage.
 107             unreachable!()
 108         }
 109     }
 110
 111     // List external crates used by the current crate.
 112     pub fn get_external_crates(&self) -> Vec<ExternalCrateData> {
 113         let mut result = Vec::with_capacity(self.tcx.crates().len());
 114
 115         for &n in self.tcx.crates().iter() {
 116             let span = match self.tcx.extern_crate(n.as_def_id()) {
 117                 Some(&ExternCrate { span, .. }) => span,
 118                 None => {
 119                     debug!("skipping crate {}, no data", n);
 120                     continue;
 121                 }
 122             };
 123             let lo_loc = self.span_utils.sess.source_map().lookup_char_pos(span.lo());
 124             result.push(ExternalCrateData {
 125                 // FIXME: change file_name field to PathBuf in rls-data
 126                 // https://github.com/nrc/rls-data/issues/7
 127                 file_name: self.span_utils.make_filename_string(&lo_loc.file),
 128                 num: n.as_u32(),
 129                 id: GlobalCrateId {
 130                     name: self.tcx.crate_name(n).to_string(),
 131                     disambiguator: self.tcx.crate_disambiguator(n).to_fingerprint().as_value(),
 132                 },
 133             });
 134         }
 135
 136         result
 137     }
 138
 139     pub fn get_extern_item_data(&self, item: &hir::ForeignItem<'_>) -> Option<Data> {
 140         let def_id = self.tcx.hir().local_def_id(item.hir_id).to_def_id();
 141         let qualname = format!("::{}", self.tcx.def_path_str(def_id));
 142         match item.kind {
 143             hir::ForeignItemKind::Fn(ref decl, arg_names, ref generics) => {
 144                 filter!(self.span_utils, item.ident.span);
 145
 146                 Some(Data::DefData(Def {
 147                     kind: DefKind::ForeignFunction,
 148                     id: id_from_def_id(def_id),
 149                     span: self.span_from_span(item.ident.span),
 150                     name: item.ident.to_string(),
 151                     qualname,
 152                     value: fn_to_string(
 153                         decl,
 154                         hir::FnHeader {
 155                             // functions in extern block are implicitly unsafe
 156                             unsafety: hir::Unsafety::Unsafe,
 157                             // functions in extern block cannot be const
 158                             constness: hir::Constness::NotConst,
 159                             abi: self.tcx.hir().get_foreign_abi(item.hir_id),
 160                             // functions in extern block cannot be async
 161                             asyncness: hir::IsAsync::NotAsync,
 162                         },
 163                         Some(item.ident.name),
 164                         generics,
 165                         &item.vis,
 166                         arg_names,
 167                         None,
 168                     ),
 169                     parent: None,
 170                     children: vec![],
 171                     decl_id: None,
 172                     docs: self.docs_for_attrs(&item.attrs),
 173                     sig: sig::foreign_item_signature(item, self),
 174                     attributes: lower_attributes(item.attrs.to_vec(), self),
 175                 }))
 176             }
 177             hir::ForeignItemKind::Static(ref ty, _) => {
 178                 filter!(self.span_utils, item.ident.span);
 179
 180                 let id = id_from_def_id(def_id);
 181                 let span = self.span_from_span(item.ident.span);
 182
 183                 Some(Data::DefData(Def {
 184                     kind: DefKind::ForeignStatic,
 185                     id,
 186                     span,
 187                     name: item.ident.to_string(),
 188                     qualname,
 189                     value: ty_to_string(ty),
 190                     parent: None,
 191                     children: vec![],
 192                     decl_id: None,
 193                     docs: self.docs_for_attrs(&item.attrs),
 194                     sig: sig::foreign_item_signature(item, self),
 195                     attributes: lower_attributes(item.attrs.to_vec(), self),
 196                 }))
 197             }
 198             // FIXME(plietar): needs a new DefKind in rls-data
 199             hir::ForeignItemKind::Type => None,
 200         }
 201     }
 202
 203     pub fn get_item_data(&self, item: &hir::Item<'_>) -> Option<Data> {
 204         let def_id = self.tcx.hir().local_def_id(item.hir_id).to_def_id();
 205         match item.kind {
 206             hir::ItemKind::Fn(ref sig, ref generics, _) => {
 207                 let qualname = format!("::{}", self.tcx.def_path_str(def_id));
 208                 filter!(self.span_utils, item.ident.span);
 209                 Some(Data::DefData(Def {
 210                     kind: DefKind::Function,
 211                     id: id_from_def_id(def_id),
 212                     span: self.span_from_span(item.ident.span),
 213                     name: item.ident.to_string(),
 214                     qualname,
 215                     value: fn_to_string(
 216                         sig.decl,
 217                         sig.header,
 218                         Some(item.ident.name),
 219                         generics,
 220                         &item.vis,
 221                         &[],
 222                         None,
 223                     ),
 224                     parent: None,
 225                     children: vec![],
 226                     decl_id: None,
 227                     docs: self.docs_for_attrs(&item.attrs),
 228                     sig: sig::item_signature(item, self),
 229                     attributes: lower_attributes(item.attrs.to_vec(), self),
 230                 }))
 231             }
 232             hir::ItemKind::Static(ref typ, ..) => {
 233                 let qualname = format!("::{}", self.tcx.def_path_str(def_id));
 234
 235                 filter!(self.span_utils, item.ident.span);
 236
 237                 let id = id_from_def_id(def_id);
 238                 let span = self.span_from_span(item.ident.span);
 239
 240                 Some(Data::DefData(Def {
 241                     kind: DefKind::Static,
 242                     id,
 243                     span,
 244                     name: item.ident.to_string(),
 245                     qualname,
 246                     value: ty_to_string(&typ),
 247                     parent: None,
 248                     children: vec![],
 249                     decl_id: None,
 250                     docs: self.docs_for_attrs(&item.attrs),
 251                     sig: sig::item_signature(item, self),
 252                     attributes: lower_attributes(item.attrs.to_vec(), self),
 253                 }))
 254             }
 255             hir::ItemKind::Const(ref typ, _) => {
 256                 let qualname = format!("::{}", self.tcx.def_path_str(def_id));
 257                 filter!(self.span_utils, item.ident.span);
 258
 259                 let id = id_from_def_id(def_id);
 260                 let span = self.span_from_span(item.ident.span);
 261
 262                 Some(Data::DefData(Def {
 263                     kind: DefKind::Const,
 264                     id,
 265                     span,
 266                     name: item.ident.to_string(),
 267                     qualname,
 268                     value: ty_to_string(typ),
 269                     parent: None,
 270                     children: vec![],
 271                     decl_id: None,
 272                     docs: self.docs_for_attrs(&item.attrs),
 273                     sig: sig::item_signature(item, self),
 274                     attributes: lower_attributes(item.attrs.to_vec(), self),
 275                 }))
 276             }
 277             hir::ItemKind::Mod(ref m) => {
 278                 let qualname = format!("::{}", self.tcx.def_path_str(def_id));
 279
 280                 let sm = self.tcx.sess.source_map();
 281                 let filename = sm.span_to_filename(m.inner);
 282
 283                 filter!(self.span_utils, item.ident.span);
 284
 285                 Some(Data::DefData(Def {
 286                     kind: DefKind::Mod,
 287                     id: id_from_def_id(def_id),
 288                     name: item.ident.to_string(),
 289                     qualname,
 290                     span: self.span_from_span(item.ident.span),
 291                     value: filename.to_string(),
 292                     parent: None,
 293                     children: m.item_ids.iter().map(|i| id_from_hir_id(i.id, self)).collect(),
 294                     decl_id: None,
 295                     docs: self.docs_for_attrs(&item.attrs),
 296                     sig: sig::item_signature(item, self),
 297                     attributes: lower_attributes(item.attrs.to_vec(), self),
 298                 }))
 299             }
 300             hir::ItemKind::Enum(ref def, ref generics) => {
 301                 let name = item.ident.to_string();
 302                 let qualname = format!("::{}", self.tcx.def_path_str(def_id));
 303                 filter!(self.span_utils, item.ident.span);
 304                 let value =
 305                     enum_def_to_string(def, generics, item.ident.name, item.span, &item.vis);
 306                 Some(Data::DefData(Def {
 307                     kind: DefKind::Enum,
 308                     id: id_from_def_id(def_id),
 309                     span: self.span_from_span(item.ident.span),
 310                     name,
 311                     qualname,
 312                     value,
 313                     parent: None,
 314                     children: def.variants.iter().map(|v| id_from_hir_id(v.id, self)).collect(),
 315                     decl_id: None,
 316                     docs: self.docs_for_attrs(&item.attrs),
 317                     sig: sig::item_signature(item, self),
 318                     attributes: lower_attributes(item.attrs.to_vec(), self),
 319                 }))
 320             }
 321             hir::ItemKind::Impl { ref of_trait, ref self_ty, ref items, .. } => {
 322                 if let hir::TyKind::Path(hir::QPath::Resolved(_, ref path)) = self_ty.kind {
 323                     // Common case impl for a struct or something basic.
 324                     if generated_code(path.span) {
 325                         return None;
 326                     }
 327                     let sub_span = path.segments.last().unwrap().ident.span;
 328                     filter!(self.span_utils, sub_span);
 329
 330                     let impl_id = self.next_impl_id();
 331                     let span = self.span_from_span(sub_span);
 332
 333                     let type_data = self.lookup_def_id(self_ty.hir_id);
 334                     type_data.map(|type_data| {
 335                         Data::RelationData(
 336                             Relation {
 337                                 kind: RelationKind::Impl { id: impl_id },
 338                                 span: span.clone(),
 339                                 from: id_from_def_id(type_data),
 340                                 to: of_trait
 341                                     .as_ref()
 342                                     .and_then(|t| self.lookup_def_id(t.hir_ref_id))
 343                                     .map(id_from_def_id)
 344                                     .unwrap_or_else(null_id),
 345                             },
 346                             Impl {
 347                                 id: impl_id,
 348                                 kind: match *of_trait {
 349                                     Some(_) => ImplKind::Direct,
 350                                     None => ImplKind::Inherent,
 351                                 },
 352                                 span,
 353                                 value: String::new(),
 354                                 parent: None,
 355                                 children: items
 356                                     .iter()
 357                                     .map(|i| id_from_hir_id(i.id.hir_id, self))
 358                                     .collect(),
 359                                 docs: String::new(),
 360                                 sig: None,
 361                                 attributes: vec![],
 362                             },
 363                         )
 364                     })
 365                 } else {
 366                     None
 367                 }
 368             }
 369             _ => {
 370                 // FIXME
 371                 bug!();
 372             }
 373         }
 374     }
 375
 376     pub fn get_field_data(&self, field: &hir::StructField<'_>, scope: hir::HirId) -> Option<Def> {
 377         let name = field.ident.to_string();
 378         let scope_def_id = self.tcx.hir().local_def_id(scope).to_def_id();
 379         let qualname = format!("::{}::{}", self.tcx.def_path_str(scope_def_id), field.ident);
 380         filter!(self.span_utils, field.ident.span);
 381         let field_def_id = self.tcx.hir().local_def_id(field.hir_id).to_def_id();
 382         let typ = self.tcx.type_of(field_def_id).to_string();
 383
 384         let id = id_from_def_id(field_def_id);
 385         let span = self.span_from_span(field.ident.span);
 386
 387         Some(Def {
 388             kind: DefKind::Field,
 389             id,
 390             span,
 391             name,
 392             qualname,
 393             value: typ,
 394             parent: Some(id_from_def_id(scope_def_id)),
 395             children: vec![],
 396             decl_id: None,
 397             docs: self.docs_for_attrs(&field.attrs),
 398             sig: sig::field_signature(field, self),
 399             attributes: lower_attributes(field.attrs.to_vec(), self),
 400         })
 401     }
 402
 403     // FIXME would be nice to take a MethodItem here, but the ast provides both
 404     // trait and impl flavours, so the caller must do the disassembly.
 405     pub fn get_method_data(&self, hir_id: hir::HirId, ident: Ident, span: Span) -> Option<Def> {
 406         // The qualname for a method is the trait name or name of the struct in an impl in
 407         // which the method is declared in, followed by the method's name.
 408         let def_id = self.tcx.hir().local_def_id(hir_id).to_def_id();
 409         let (qualname, parent_scope, decl_id, docs, attributes) =
 410             match self.tcx.impl_of_method(def_id) {
 411                 Some(impl_id) => match self.tcx.hir().get_if_local(impl_id) {
 412                     Some(Node::Item(item)) => match item.kind {
 413                         hir::ItemKind::Impl { ref self_ty, .. } => {
 414                             let hir = self.tcx.hir();
 415
 416                             let mut qualname = String::from("<");
 417                             qualname
 418                                 .push_str(&rustc_hir_pretty::id_to_string(&hir, self_ty.hir_id));
 419
 420                             let trait_id = self.tcx.trait_id_of_impl(impl_id);
 421                             let mut docs = String::new();
 422                             let mut attrs = vec![];
 423                             if let Some(Node::ImplItem(item)) = hir.find(hir_id) {
 424                                 docs = self.docs_for_attrs(&item.attrs);
 425                                 attrs = item.attrs.to_vec();
 426                             }
 427
 428                             let mut decl_id = None;
 429                             if let Some(def_id) = trait_id {
 430                                 // A method in a trait impl.
 431                                 qualname.push_str(" as ");
 432                                 qualname.push_str(&self.tcx.def_path_str(def_id));
 433
 434                                 decl_id = self
 435                                     .tcx
 436                                     .associated_items(def_id)
 437                                     .filter_by_name_unhygienic(ident.name)
 438                                     .next()
 439                                     .map(|item| item.def_id);
 440                             }
 441                             qualname.push_str(">");
 442
 443                             (qualname, trait_id, decl_id, docs, attrs)
 444                         }
 445                         _ => {
 446                             span_bug!(
 447                                 span,
 448                                 "Container {:?} for method {} not an impl?",
 449                                 impl_id,
 450                                 hir_id
 451                             );
 452                         }
 453                     },
 454                     r => {
 455                         span_bug!(
 456                             span,
 457                             "Container {:?} for method {} is not a node item {:?}",
 458                             impl_id,
 459                             hir_id,
 460                             r
 461                         );
 462                     }
 463                 },
 464                 None => match self.tcx.trait_of_item(def_id) {
 465                     Some(def_id) => {
 466                         let mut docs = String::new();
 467                         let mut attrs = vec![];
 468
 469                         if let Some(Node::TraitItem(item)) = self.tcx.hir().find(hir_id) {
 470                             docs = self.docs_for_attrs(&item.attrs);
 471                             attrs = item.attrs.to_vec();
 472                         }
 473
 474                         (
 475                             format!("::{}", self.tcx.def_path_str(def_id)),
 476                             Some(def_id),
 477                             None,
 478                             docs,
 479                             attrs,
 480                         )
 481                     }
 482                     None => {
 483                         debug!("could not find container for method {} at {:?}", hir_id, span);
 484                         // This is not necessarily a bug, if there was a compilation error,
 485                         // the typeck results we need might not exist.
 486                         return None;
 487                     }
 488                 },
 489             };
 490
 491         let qualname = format!("{}::{}", qualname, ident.name);
 492
 493         filter!(self.span_utils, ident.span);
 494
 495         Some(Def {
 496             kind: DefKind::Method,
 497             id: id_from_def_id(def_id),
 498             span: self.span_from_span(ident.span),
 499             name: ident.name.to_string(),
 500             qualname,
 501             // FIXME you get better data here by using the visitor.
 502             value: String::new(),
 503             parent: parent_scope.map(id_from_def_id),
 504             children: vec![],
 505             decl_id: decl_id.map(id_from_def_id),
 506             docs,
 507             sig: None,
 508             attributes: lower_attributes(attributes, self),
 509         })
 510     }
 511
 512     pub fn get_trait_ref_data(&self, trait_ref: &hir::TraitRef<'_>) -> Option<Ref> {
 513         self.lookup_def_id(trait_ref.hir_ref_id).and_then(|def_id| {
 514             let span = trait_ref.path.span;
 515             if generated_code(span) {
 516                 return None;
 517             }
 518             let sub_span = trait_ref.path.segments.last().unwrap().ident.span;
 519             filter!(self.span_utils, sub_span);
 520             let span = self.span_from_span(sub_span);
 521             Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(def_id) })
 522         })
 523     }
 524
 525     pub fn get_expr_data(&self, expr: &hir::Expr<'_>) -> Option<Data> {
 526         let ty = self.typeck_results().expr_ty_adjusted_opt(expr)?;
 527         if matches!(ty.kind, ty::Error(_)) {
 528             return None;
 529         }
 530         match expr.kind {
 531             hir::ExprKind::Field(ref sub_ex, ident) => {
 532                 match self.typeck_results().expr_ty_adjusted(&sub_ex).kind {
 533                     ty::Adt(def, _) if !def.is_enum() => {
 534                         let variant = &def.non_enum_variant();
 535                         filter!(self.span_utils, ident.span);
 536                         let span = self.span_from_span(ident.span);
 537                         Some(Data::RefData(Ref {
 538                             kind: RefKind::Variable,
 539                             span,
 540                             ref_id: self
 541                                 .tcx
 542                                 .find_field_index(ident, variant)
 543                                 .map(|index| id_from_def_id(variant.fields[index].did))
 544                                 .unwrap_or_else(null_id),
 545                         }))
 546                     }
 547                     ty::Tuple(..) => None,
 548                     _ => {
 549                         debug!("expected struct or union type, found {:?}", ty);
 550                         None
 551                     }
 552                 }
 553             }
 554             hir::ExprKind::Struct(qpath, ..) => match ty.kind {
 555                 ty::Adt(def, _) => {
 556                     let sub_span = qpath.last_segment_span();
 557                     filter!(self.span_utils, sub_span);
 558                     let span = self.span_from_span(sub_span);
 559                     Some(Data::RefData(Ref {
 560                         kind: RefKind::Type,
 561                         span,
 562                         ref_id: id_from_def_id(def.did),
 563                     }))
 564                 }
 565                 _ => {
 566                     debug!("expected adt, found {:?}", ty);
 567                     None
 568                 }
 569             },
 570             hir::ExprKind::MethodCall(ref seg, ..) => {
 571                 let method_id = match self.typeck_results().type_dependent_def_id(expr.hir_id) {
 572                     Some(id) => id,
 573                     None => {
 574                         debug!("could not resolve method id for {:?}", expr);
 575                         return None;
 576                     }
 577                 };
 578                 let (def_id, decl_id) = match self.tcx.associated_item(method_id).container {
 579                     ty::ImplContainer(_) => (Some(method_id), None),
 580                     ty::TraitContainer(_) => (None, Some(method_id)),
 581                 };
 582                 let sub_span = seg.ident.span;
 583                 filter!(self.span_utils, sub_span);
 584                 let span = self.span_from_span(sub_span);
 585                 Some(Data::RefData(Ref {
 586                     kind: RefKind::Function,
 587                     span,
 588                     ref_id: def_id.or(decl_id).map(id_from_def_id).unwrap_or_else(null_id),
 589                 }))
 590             }
 591             hir::ExprKind::Path(ref path) => {
 592                 self.get_path_data(expr.hir_id, path).map(Data::RefData)
 593             }
 594             _ => {
 595                 // FIXME
 596                 bug!("invalid expression: {:?}", expr);
 597             }
 598         }
 599     }
 600
 601     pub fn get_path_res(&self, hir_id: hir::HirId) -> Res {
 602         match self.tcx.hir().get(hir_id) {
 603             Node::TraitRef(tr) => tr.path.res,
 604
 605             Node::Item(&hir::Item { kind: hir::ItemKind::Use(path, _), .. }) => path.res,
 606             Node::Visibility(&Spanned {
 607                 node: hir::VisibilityKind::Restricted { ref path, .. },
 608                 ..
 609             }) => path.res,
 610
 611             Node::PathSegment(seg) => match seg.res {
 612                 Some(res) if res != Res::Err => res,
 613                 _ => {
 614                     let parent_node = self.tcx.hir().get_parent_node(hir_id);
 615                     self.get_path_res(parent_node)
 616                 }
 617             },
 618
 619             Node::Expr(&hir::Expr { kind: hir::ExprKind::Struct(ref qpath, ..), .. }) => {
 620                 self.typeck_results().qpath_res(qpath, hir_id)
 621             }
 622
 623             Node::Expr(&hir::Expr { kind: hir::ExprKind::Path(ref qpath), .. })
 624             | Node::Pat(&hir::Pat {
 625                 kind:
 626                     hir::PatKind::Path(ref qpath)
 627                     | hir::PatKind::Struct(ref qpath, ..)
 628                     | hir::PatKind::TupleStruct(ref qpath, ..),
 629                 ..
 630             })
 631             | Node::Ty(&hir::Ty { kind: hir::TyKind::Path(ref qpath), .. }) => match qpath {
 632                 hir::QPath::Resolved(_, path) => path.res,
 633                 hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
 634                     .maybe_typeck_results
 635                     .map_or(Res::Err, |typeck_results| typeck_results.qpath_res(qpath, hir_id)),
 636             },
 637
 638             Node::Binding(&hir::Pat {
 639                 kind: hir::PatKind::Binding(_, canonical_id, ..), ..
 640             }) => Res::Local(canonical_id),
 641
 642             _ => Res::Err,
 643         }
 644     }
 645
 646     pub fn get_path_data(&self, id: hir::HirId, path: &hir::QPath<'_>) -> Option<Ref> {
 647         let segment = match path {
 648             hir::QPath::Resolved(_, path) => path.segments.last(),
 649             hir::QPath::TypeRelative(_, segment) => Some(*segment),
 650             hir::QPath::LangItem(..) => None,
 651         };
 652         segment.and_then(|seg| {
 653             self.get_path_segment_data(seg).or_else(|| self.get_path_segment_data_with_id(seg, id))
 654         })
 655     }
 656
 657     pub fn get_path_segment_data(&self, path_seg: &hir::PathSegment<'_>) -> Option<Ref> {
 658         self.get_path_segment_data_with_id(path_seg, path_seg.hir_id?)
 659     }
 660
 661     pub fn get_path_segment_data_with_id(
 662         &self,
 663         path_seg: &hir::PathSegment<'_>,
 664         id: hir::HirId,
 665     ) -> Option<Ref> {
 666         // Returns true if the path is function type sugar, e.g., `Fn(A) -> B`.
 667         fn fn_type(seg: &hir::PathSegment<'_>) -> bool {
 668             seg.args.map(|args| args.parenthesized).unwrap_or(false)
 669         }
 670
 671         let res = self.get_path_res(id);
 672         let span = path_seg.ident.span;
 673         filter!(self.span_utils, span);
 674         let span = self.span_from_span(span);
 675
 676         match res {
 677             Res::Local(id) => {
 678                 Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_hir_id(id, self) })
 679             }
 680             Res::Def(HirDefKind::Trait, def_id) if fn_type(path_seg) => {
 681                 Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(def_id) })
 682             }
 683             Res::Def(
 684                 HirDefKind::Struct
 685                 | HirDefKind::Variant
 686                 | HirDefKind::Union
 687                 | HirDefKind::Enum
 688                 | HirDefKind::TyAlias
 689                 | HirDefKind::ForeignTy
 690                 | HirDefKind::TraitAlias
 691                 | HirDefKind::AssocTy
 692                 | HirDefKind::Trait
 693                 | HirDefKind::OpaqueTy
 694                 | HirDefKind::TyParam,
 695                 def_id,
 696             ) => Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(def_id) }),
 697             Res::Def(HirDefKind::ConstParam, def_id) => {
 698                 Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(def_id) })
 699             }
 700             Res::Def(HirDefKind::Ctor(..), def_id) => {
 701                 // This is a reference to a tuple struct or an enum variant where the def_id points
 702                 // to an invisible constructor function. That is not a very useful
 703                 // def, so adjust to point to the tuple struct or enum variant itself.
 704                 let parent_def_id = self.tcx.parent(def_id).unwrap();
 705                 Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(parent_def_id) })
 706             }
 707             Res::Def(HirDefKind::Static | HirDefKind::Const | HirDefKind::AssocConst, _) => {
 708                 Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(res.def_id()) })
 709             }
 710             Res::Def(HirDefKind::AssocFn, decl_id) => {
 711                 let def_id = if decl_id.is_local() {
 712                     let ti = self.tcx.associated_item(decl_id);
 713
 714                     self.tcx
 715                         .associated_items(ti.container.id())
 716                         .filter_by_name_unhygienic(ti.ident.name)
 717                         .find(|item| item.defaultness.has_value())
 718                         .map(|item| item.def_id)
 719                 } else {
 720                     None
 721                 };
 722                 Some(Ref {
 723                     kind: RefKind::Function,
 724                     span,
 725                     ref_id: id_from_def_id(def_id.unwrap_or(decl_id)),
 726                 })
 727             }
 728             Res::Def(HirDefKind::Fn, def_id) => {
 729                 Some(Ref { kind: RefKind::Function, span, ref_id: id_from_def_id(def_id) })
 730             }
 731             Res::Def(HirDefKind::Mod, def_id) => {
 732                 Some(Ref { kind: RefKind::Mod, span, ref_id: id_from_def_id(def_id) })
 733             }
 734
 735             Res::Def(
 736                 HirDefKind::Macro(..)
 737                 | HirDefKind::ExternCrate
 738                 | HirDefKind::ForeignMod
 739                 | HirDefKind::LifetimeParam
 740                 | HirDefKind::AnonConst
 741                 | HirDefKind::Use
 742                 | HirDefKind::Field
 743                 | HirDefKind::GlobalAsm
 744                 | HirDefKind::Impl
 745                 | HirDefKind::Closure
 746                 | HirDefKind::Generator,
 747                 _,
 748             )
 749             | Res::PrimTy(..)
 750             | Res::SelfTy(..)
 751             | Res::ToolMod
 752             | Res::NonMacroAttr(..)
 753             | Res::SelfCtor(..)
 754             | Res::Err => None,
 755         }
 756     }
 757
 758     pub fn get_field_ref_data(
 759         &self,
 760         field_ref: &hir::Field<'_>,
 761         variant: &ty::VariantDef,
 762     ) -> Option<Ref> {
 763         filter!(self.span_utils, field_ref.ident.span);
 764         self.tcx.find_field_index(field_ref.ident, variant).map(|index| {
 765             let span = self.span_from_span(field_ref.ident.span);
 766             Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(variant.fields[index].did) }
 767         })
 768     }
 769
 770     /// Attempt to return MacroRef for any AST node.
 771     ///
 772     /// For a given piece of AST defined by the supplied Span and NodeId,
 773     /// returns `None` if the node is not macro-generated or the span is malformed,
 774     /// else uses the expansion callsite and callee to return some MacroRef.
 775     pub fn get_macro_use_data(&self, span: Span) -> Option<MacroRef> {
 776         if !generated_code(span) {
 777             return None;
 778         }
 779         // Note we take care to use the source callsite/callee, to handle
 780         // nested expansions and ensure we only generate data for source-visible
 781         // macro uses.
 782         let callsite = span.source_callsite();
 783         let callsite_span = self.span_from_span(callsite);
 784         let callee = span.source_callee()?;
 785
 786         let mac_name = match callee.kind {
 787             ExpnKind::Macro(kind, name) => match kind {
 788                 MacroKind::Bang => name,
 789
 790                 // Ignore attribute macros, their spans are usually mangled
 791                 // FIXME(eddyb) is this really the case anymore?
 792                 MacroKind::Attr | MacroKind::Derive => return None,
 793             },
 794
 795             // These are not macros.
 796             // FIXME(eddyb) maybe there is a way to handle them usefully?
 797             ExpnKind::Root | ExpnKind::AstPass(_) | ExpnKind::Desugaring(_) => return None,
 798         };
 799
 800         let callee_span = self.span_from_span(callee.def_site);
 801         Some(MacroRef {
 802             span: callsite_span,
 803             qualname: mac_name.to_string(), // FIXME: generate the real qualname
 804             callee_span,
 805         })
 806     }
 807
 808     fn lookup_def_id(&self, ref_id: hir::HirId) -> Option<DefId> {
 809         match self.get_path_res(ref_id) {
 810             Res::PrimTy(_) | Res::SelfTy(..) | Res::Err => None,
 811             def => def.opt_def_id(),
 812         }
 813     }
 814
 815     fn docs_for_attrs(&self, attrs: &[ast::Attribute]) -> String {
 816         let mut result = String::new();
 817
 818         for attr in attrs {
 819             if let Some(val) = attr.doc_str() {
 820                 // FIXME: Should save-analysis beautify doc strings itself or leave it to users?
 821                 result.push_str(&beautify_doc_string(val));
 822                 result.push('\n');
 823             } else if self.tcx.sess.check_name(attr, sym::doc) {
 824                 if let Some(meta_list) = attr.meta_item_list() {
 825                     meta_list
 826                         .into_iter()
 827                         .filter(|it| it.has_name(sym::include))
 828                         .filter_map(|it| it.meta_item_list().map(|l| l.to_owned()))
 829                         .flat_map(|it| it)
 830                         .filter(|meta| meta.has_name(sym::contents))
 831                         .filter_map(|meta| meta.value_str())
 832                         .for_each(|val| {
 833                             result.push_str(&val.as_str());
 834                             result.push('\n');
 835                         });
 836                 }
 837             }
 838         }
 839
 840         if !self.config.full_docs {
 841             if let Some(index) = result.find("\n\n") {
 842                 result.truncate(index);
 843             }
 844         }
 845
 846         result
 847     }
 848
 849     fn next_impl_id(&self) -> u32 {
 850         let next = self.impl_counter.get();
 851         self.impl_counter.set(next + 1);
 852         next
 853     }
 854 }
 855
 856 // An AST visitor for collecting paths (e.g., the names of structs) and formal
 857 // variables (idents) from patterns.
 858 struct PathCollector<'l> {
 859     tcx: TyCtxt<'l>,
 860     collected_paths: Vec<(hir::HirId, &'l hir::QPath<'l>)>,
 861     collected_idents: Vec<(hir::HirId, Ident, hir::Mutability)>,
 862 }
 863
 864 impl<'l> PathCollector<'l> {
 865     fn new(tcx: TyCtxt<'l>) -> PathCollector<'l> {
 866         PathCollector { tcx, collected_paths: vec![], collected_idents: vec![] }
 867     }
 868 }
 869
 870 impl<'l> Visitor<'l> for PathCollector<'l> {
 871     type Map = Map<'l>;
 872
 873     fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
 874         intravisit::NestedVisitorMap::All(self.tcx.hir())
 875     }
 876
 877     fn visit_pat(&mut self, p: &'l hir::Pat<'l>) {
 878         match p.kind {
 879             hir::PatKind::Struct(ref path, ..) => {
 880                 self.collected_paths.push((p.hir_id, path));
 881             }
 882             hir::PatKind::TupleStruct(ref path, ..) | hir::PatKind::Path(ref path) => {
 883                 self.collected_paths.push((p.hir_id, path));
 884             }
 885             hir::PatKind::Binding(bm, _, ident, _) => {
 886                 debug!(
 887                     "PathCollector, visit ident in pat {}: {:?} {:?}",
 888                     ident, p.span, ident.span
 889                 );
 890                 let immut = match bm {
 891                     // Even if the ref is mut, you can't change the ref, only
 892                     // the data pointed at, so showing the initialising expression
 893                     // is still worthwhile.
 894                     hir::BindingAnnotation::Unannotated | hir::BindingAnnotation::Ref => {
 895                         hir::Mutability::Not
 896                     }
 897                     hir::BindingAnnotation::Mutable | hir::BindingAnnotation::RefMut => {
 898                         hir::Mutability::Mut
 899                     }
 900                 };
 901                 self.collected_idents.push((p.hir_id, ident, immut));
 902             }
 903             _ => {}
 904         }
 905         intravisit::walk_pat(self, p);
 906     }
 907 }
 908
 909 /// Defines what to do with the results of saving the analysis.
 910 pub trait SaveHandler {
 911     fn save(&mut self, save_ctxt: &SaveContext<'_>, analysis: &Analysis);
 912 }
 913
 914 /// Dump the save-analysis results to a file.
 915 pub struct DumpHandler<'a> {
 916     odir: Option<&'a Path>,
 917     cratename: String,
 918 }
 919
 920 impl<'a> DumpHandler<'a> {
 921     pub fn new(odir: Option<&'a Path>, cratename: &str) -> DumpHandler<'a> {
 922         DumpHandler { odir, cratename: cratename.to_owned() }
 923     }
 924
 925     fn output_file(&self, ctx: &SaveContext<'_>) -> (BufWriter<File>, PathBuf) {
 926         let sess = &ctx.tcx.sess;
 927         let file_name = match ctx.config.output_file {
 928             Some(ref s) => PathBuf::from(s),
 929             None => {
 930                 let mut root_path = match self.odir {
 931                     Some(val) => val.join("save-analysis"),
 932                     None => PathBuf::from("save-analysis-temp"),
 933                 };
 934
 935                 if let Err(e) = std::fs::create_dir_all(&root_path) {
 936                     error!("Could not create directory {}: {}", root_path.display(), e);
 937                 }
 938
 939                 let executable = sess.crate_types().iter().any(|ct| *ct == CrateType::Executable);
 940                 let mut out_name = if executable { String::new() } else { "lib".to_owned() };
 941                 out_name.push_str(&self.cratename);
 942                 out_name.push_str(&sess.opts.cg.extra_filename);
 943                 out_name.push_str(".json");
 944                 root_path.push(&out_name);
 945
 946                 root_path
 947             }
 948         };
 949
 950         info!("Writing output to {}", file_name.display());
 951
 952         let output_file = BufWriter::new(File::create(&file_name).unwrap_or_else(|e| {
 953             sess.fatal(&format!("Could not open {}: {}", file_name.display(), e))
 954         }));
 955
 956         (output_file, file_name)
 957     }
 958 }
 959
 960 impl SaveHandler for DumpHandler<'_> {
 961     fn save(&mut self, save_ctxt: &SaveContext<'_>, analysis: &Analysis) {
 962         let sess = &save_ctxt.tcx.sess;
 963         let (output, file_name) = self.output_file(&save_ctxt);
 964         if let Err(e) = serde_json::to_writer(output, &analysis) {
 965             error!("Can't serialize save-analysis: {:?}", e);
 966         }
 967
 968         if sess.opts.json_artifact_notifications {
 969             sess.parse_sess.span_diagnostic.emit_artifact_notification(&file_name, "save-analysis");
 970         }
 971     }
 972 }
 973
 974 /// Call a callback with the results of save-analysis.
 975 pub struct CallbackHandler<'b> {
 976     pub callback: &'b mut dyn FnMut(&rls_data::Analysis),
 977 }
 978
 979 impl SaveHandler for CallbackHandler<'_> {
 980     fn save(&mut self, _: &SaveContext<'_>, analysis: &Analysis) {
 981         (self.callback)(analysis)
 982     }
 983 }
 984
 985 pub fn process_crate<'l, 'tcx, H: SaveHandler>(
 986     tcx: TyCtxt<'tcx>,
 987     cratename: &str,
 988     input: &'l Input,
 989     config: Option<Config>,
 990     mut handler: H,
 991 ) {
 992     tcx.dep_graph.with_ignore(|| {
 993         info!("Dumping crate {}", cratename);
 994
 995         // Privacy checking requires and is done after type checking; use a
 996         // fallback in case the access levels couldn't have been correctly computed.
 997         let access_levels = match tcx.sess.compile_status() {
 998             Ok(..) => tcx.privacy_access_levels(LOCAL_CRATE),
 999             Err(..) => tcx.arena.alloc(AccessLevels::default()),
1000         };
1001
1002         let save_ctxt = SaveContext {
1003             tcx,
1004             maybe_typeck_results: None,
1005             access_levels: &access_levels,
1006             span_utils: SpanUtils::new(&tcx.sess),
1007             config: find_config(config),
1008             impl_counter: Cell::new(0),
1009         };
1010
1011         let mut visitor = DumpVisitor::new(save_ctxt);
1012
1013         visitor.dump_crate_info(cratename, tcx.hir().krate());
1014         visitor.dump_compilation_options(input, cratename);
1015         visitor.process_crate(tcx.hir().krate());
1016
1017         handler.save(&visitor.save_ctxt, &visitor.analysis())
1018     })
1019 }
1020
1021 fn find_config(supplied: Option<Config>) -> Config {
1022     if let Some(config) = supplied {
1023         return config;
1024     }
1025
1026     match env::var_os("RUST_SAVE_ANALYSIS_CONFIG") {
1027         None => Config::default(),
1028         Some(config) => config
1029             .to_str()
1030             .ok_or(())
1031             .map_err(|_| error!("`RUST_SAVE_ANALYSIS_CONFIG` isn't UTF-8"))
1032             .and_then(|cfg| {
1033                 serde_json::from_str(cfg)
1034                     .map_err(|_| error!("Could not deserialize save-analysis config"))
1035             })
1036             .unwrap_or_default(),
1037     }
1038 }
1039
1040 // Utility functions for the module.
1041
1042 // Helper function to escape quotes in a string
1043 fn escape(s: String) -> String {
1044     s.replace("\"", "\"\"")
1045 }
1046
1047 // Helper function to determine if a span came from a
1048 // macro expansion or syntax extension.
1049 fn generated_code(span: Span) -> bool {
1050     span.from_expansion() || span.is_dummy()
1051 }
1052
1053 // DefId::index is a newtype and so the JSON serialisation is ugly. Therefore
1054 // we use our own Id which is the same, but without the newtype.
1055 fn id_from_def_id(id: DefId) -> rls_data::Id {
1056     rls_data::Id { krate: id.krate.as_u32(), index: id.index.as_u32() }
1057 }
1058
1059 fn id_from_hir_id(id: hir::HirId, scx: &SaveContext<'_>) -> rls_data::Id {
1060     let def_id = scx.tcx.hir().opt_local_def_id(id);
1061     def_id.map(|id| id_from_def_id(id.to_def_id())).unwrap_or_else(|| {
1062         // Create a *fake* `DefId` out of a `HirId` by combining the owner
1063         // `local_def_index` and the `local_id`.
1064         // This will work unless you have *billions* of definitions in a single
1065         // crate (very unlikely to actually happen).
1066         rls_data::Id {
1067             krate: LOCAL_CRATE.as_u32(),
1068             index: id.owner.local_def_index.as_u32() | id.local_id.as_u32().reverse_bits(),
1069         }
1070     })
1071 }
1072
1073 fn null_id() -> rls_data::Id {
1074     rls_data::Id { krate: u32::MAX, index: u32::MAX }
1075 }
1076
1077 fn lower_attributes(attrs: Vec<ast::Attribute>, scx: &SaveContext<'_>) -> Vec<rls_data::Attribute> {
1078     attrs
1079         .into_iter()
1080         // Only retain real attributes. Doc comments are lowered separately.
1081         .filter(|attr| !attr.has_name(sym::doc))
1082         .map(|mut attr| {
1083             // Remove the surrounding '#[..]' or '#![..]' of the pretty printed
1084             // attribute. First normalize all inner attribute (#![..]) to outer
1085             // ones (#[..]), then remove the two leading and the one trailing character.
1086             attr.style = ast::AttrStyle::Outer;
1087             let value = attribute_to_string(&attr);
1088             // This str slicing works correctly, because the leading and trailing characters
1089             // are in the ASCII range and thus exactly one byte each.
1090             let value = value[2..value.len() - 1].to_string();
1091
1092             rls_data::Attribute { value, span: scx.span_from_span(attr.span) }
1093         })
1094         .collect()
1095 }