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::ast::{self, Attribute, NodeId, PatKind, DUMMY_NODE_ID};
  13 use rustc_ast::util::comments::strip_doc_comment_decoration;
  14 use rustc_ast::visit::{self, Visitor};
  15 use rustc_ast_pretty::pprust::{self, param_to_string, ty_to_string};
  16 use rustc_hir as hir;
  17 use rustc_hir::def::{CtorOf, DefKind as HirDefKind, Res};
  18 use rustc_hir::def_id::{DefId, LOCAL_CRATE};
  19 use rustc_hir::Node;
  20 use rustc_middle::middle::cstore::ExternCrate;
  21 use rustc_middle::middle::privacy::AccessLevels;
  22 use rustc_middle::ty::{self, DefIdTree, TyCtxt};
  23 use rustc_middle::{bug, span_bug};
  24 use rustc_session::config::{CrateType, Input, OutputType};
  25 use rustc_session::output::{filename_for_metadata, out_filename};
  26 use rustc_span::source_map::Spanned;
  27 use rustc_span::symbol::Ident;
  28 use rustc_span::*;
  29
  30 use std::cell::Cell;
  31 use std::default::Default;
  32 use std::env;
  33 use std::fs::File;
  34 use std::io::BufWriter;
  35 use std::path::{Path, PathBuf};
  36
  37 use dump_visitor::DumpVisitor;
  38 use span_utils::SpanUtils;
  39
  40 use rls_data::config::Config;
  41 use rls_data::{
  42     Analysis, Def, DefKind, ExternalCrateData, GlobalCrateId, Impl, ImplKind, MacroRef, Ref,
  43     RefKind, Relation, RelationKind, SpanData,
  44 };
  45
  46 use log::{debug, error, info};
  47
  48 pub struct SaveContext<'l, 'tcx> {
  49     tcx: TyCtxt<'tcx>,
  50     tables: &'l ty::TypeckTables<'tcx>,
  51     /// Used as a fallback when nesting the typeck tables during item processing
  52     /// (if these are not available for that item, e.g. don't own a body)
  53     empty_tables: &'l ty::TypeckTables<'tcx>,
  54     access_levels: &'l AccessLevels,
  55     span_utils: SpanUtils<'tcx>,
  56     config: Config,
  57     impl_counter: Cell<u32>,
  58 }
  59
  60 #[derive(Debug)]
  61 pub enum Data {
  62     RefData(Ref),
  63     DefData(Def),
  64     RelationData(Relation, Impl),
  65 }
  66
  67 impl<'l, 'tcx> SaveContext<'l, 'tcx> {
  68     fn span_from_span(&self, span: Span) -> SpanData {
  69         use rls_span::{Column, Row};
  70
  71         let sm = self.tcx.sess.source_map();
  72         let start = sm.lookup_char_pos(span.lo());
  73         let end = sm.lookup_char_pos(span.hi());
  74
  75         SpanData {
  76             file_name: start.file.name.to_string().into(),
  77             byte_start: span.lo().0,
  78             byte_end: span.hi().0,
  79             line_start: Row::new_one_indexed(start.line as u32),
  80             line_end: Row::new_one_indexed(end.line as u32),
  81             column_start: Column::new_one_indexed(start.col.0 as u32 + 1),
  82             column_end: Column::new_one_indexed(end.col.0 as u32 + 1),
  83         }
  84     }
  85
  86     // Returns path to the compilation output (e.g., libfoo-12345678.rmeta)
  87     pub fn compilation_output(&self, crate_name: &str) -> PathBuf {
  88         let sess = &self.tcx.sess;
  89         // Save-analysis is emitted per whole session, not per each crate type
  90         let crate_type = sess.crate_types()[0];
  91         let outputs = &*self.tcx.output_filenames(LOCAL_CRATE);
  92
  93         if outputs.outputs.contains_key(&OutputType::Metadata) {
  94             filename_for_metadata(sess, crate_name, outputs)
  95         } else if outputs.outputs.should_codegen() {
  96             out_filename(sess, crate_type, outputs, crate_name)
  97         } else {
  98             // Otherwise it's only a DepInfo, in which case we return early and
  99             // not even reach the analysis stage.
 100             unreachable!()
 101         }
 102     }
 103
 104     // List external crates used by the current crate.
 105     pub fn get_external_crates(&self) -> Vec<ExternalCrateData> {
 106         let mut result = Vec::with_capacity(self.tcx.crates().len());
 107
 108         for &n in self.tcx.crates().iter() {
 109             let span = match self.tcx.extern_crate(n.as_def_id()) {
 110                 Some(&ExternCrate { span, .. }) => span,
 111                 None => {
 112                     debug!("skipping crate {}, no data", n);
 113                     continue;
 114                 }
 115             };
 116             let lo_loc = self.span_utils.sess.source_map().lookup_char_pos(span.lo());
 117             result.push(ExternalCrateData {
 118                 // FIXME: change file_name field to PathBuf in rls-data
 119                 // https://github.com/nrc/rls-data/issues/7
 120                 file_name: self.span_utils.make_filename_string(&lo_loc.file),
 121                 num: n.as_u32(),
 122                 id: GlobalCrateId {
 123                     name: self.tcx.crate_name(n).to_string(),
 124                     disambiguator: self.tcx.crate_disambiguator(n).to_fingerprint().as_value(),
 125                 },
 126             });
 127         }
 128
 129         result
 130     }
 131
 132     pub fn get_extern_item_data(&self, item: &ast::ForeignItem) -> Option<Data> {
 133         let qualname = format!(
 134             "::{}",
 135             self.tcx.def_path_str(self.tcx.hir().local_def_id_from_node_id(item.id).to_def_id())
 136         );
 137         match item.kind {
 138             ast::ForeignItemKind::Fn(_, ref sig, ref generics, _) => {
 139                 filter!(self.span_utils, item.ident.span);
 140
 141                 Some(Data::DefData(Def {
 142                     kind: DefKind::ForeignFunction,
 143                     id: id_from_node_id(item.id, self),
 144                     span: self.span_from_span(item.ident.span),
 145                     name: item.ident.to_string(),
 146                     qualname,
 147                     value: make_signature(&sig.decl, generics),
 148                     parent: None,
 149                     children: vec![],
 150                     decl_id: None,
 151                     docs: self.docs_for_attrs(&item.attrs),
 152                     sig: sig::foreign_item_signature(item, self),
 153                     attributes: lower_attributes(item.attrs.clone(), self),
 154                 }))
 155             }
 156             ast::ForeignItemKind::Static(ref ty, _, _) => {
 157                 filter!(self.span_utils, item.ident.span);
 158
 159                 let id = id_from_node_id(item.id, self);
 160                 let span = self.span_from_span(item.ident.span);
 161
 162                 Some(Data::DefData(Def {
 163                     kind: DefKind::ForeignStatic,
 164                     id,
 165                     span,
 166                     name: item.ident.to_string(),
 167                     qualname,
 168                     value: ty_to_string(ty),
 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.clone(), self),
 175                 }))
 176             }
 177             // FIXME(plietar): needs a new DefKind in rls-data
 178             ast::ForeignItemKind::TyAlias(..) => None,
 179             ast::ForeignItemKind::MacCall(..) => None,
 180         }
 181     }
 182
 183     pub fn get_item_data(&self, item: &ast::Item) -> Option<Data> {
 184         match item.kind {
 185             ast::ItemKind::Fn(_, ref sig, .., ref generics, _) => {
 186                 let qualname = format!(
 187                     "::{}",
 188                     self.tcx.def_path_str(
 189                         self.tcx.hir().local_def_id_from_node_id(item.id).to_def_id()
 190                     )
 191                 );
 192                 filter!(self.span_utils, item.ident.span);
 193                 Some(Data::DefData(Def {
 194                     kind: DefKind::Function,
 195                     id: id_from_node_id(item.id, self),
 196                     span: self.span_from_span(item.ident.span),
 197                     name: item.ident.to_string(),
 198                     qualname,
 199                     value: make_signature(&sig.decl, generics),
 200                     parent: None,
 201                     children: vec![],
 202                     decl_id: None,
 203                     docs: self.docs_for_attrs(&item.attrs),
 204                     sig: sig::item_signature(item, self),
 205                     attributes: lower_attributes(item.attrs.clone(), self),
 206                 }))
 207             }
 208             ast::ItemKind::Static(ref typ, ..) => {
 209                 let qualname = format!(
 210                     "::{}",
 211                     self.tcx.def_path_str(
 212                         self.tcx.hir().local_def_id_from_node_id(item.id).to_def_id()
 213                     )
 214                 );
 215
 216                 filter!(self.span_utils, item.ident.span);
 217
 218                 let id = id_from_node_id(item.id, self);
 219                 let span = self.span_from_span(item.ident.span);
 220
 221                 Some(Data::DefData(Def {
 222                     kind: DefKind::Static,
 223                     id,
 224                     span,
 225                     name: item.ident.to_string(),
 226                     qualname,
 227                     value: ty_to_string(&typ),
 228                     parent: None,
 229                     children: vec![],
 230                     decl_id: None,
 231                     docs: self.docs_for_attrs(&item.attrs),
 232                     sig: sig::item_signature(item, self),
 233                     attributes: lower_attributes(item.attrs.clone(), self),
 234                 }))
 235             }
 236             ast::ItemKind::Const(_, ref typ, _) => {
 237                 let qualname = format!(
 238                     "::{}",
 239                     self.tcx.def_path_str(
 240                         self.tcx.hir().local_def_id_from_node_id(item.id).to_def_id()
 241                     )
 242                 );
 243                 filter!(self.span_utils, item.ident.span);
 244
 245                 let id = id_from_node_id(item.id, self);
 246                 let span = self.span_from_span(item.ident.span);
 247
 248                 Some(Data::DefData(Def {
 249                     kind: DefKind::Const,
 250                     id,
 251                     span,
 252                     name: item.ident.to_string(),
 253                     qualname,
 254                     value: ty_to_string(typ),
 255                     parent: None,
 256                     children: vec![],
 257                     decl_id: None,
 258                     docs: self.docs_for_attrs(&item.attrs),
 259                     sig: sig::item_signature(item, self),
 260                     attributes: lower_attributes(item.attrs.clone(), self),
 261                 }))
 262             }
 263             ast::ItemKind::Mod(ref m) => {
 264                 let qualname = format!(
 265                     "::{}",
 266                     self.tcx.def_path_str(
 267                         self.tcx.hir().local_def_id_from_node_id(item.id).to_def_id()
 268                     )
 269                 );
 270
 271                 let sm = self.tcx.sess.source_map();
 272                 let filename = sm.span_to_filename(m.inner);
 273
 274                 filter!(self.span_utils, item.ident.span);
 275
 276                 Some(Data::DefData(Def {
 277                     kind: DefKind::Mod,
 278                     id: id_from_node_id(item.id, self),
 279                     name: item.ident.to_string(),
 280                     qualname,
 281                     span: self.span_from_span(item.ident.span),
 282                     value: filename.to_string(),
 283                     parent: None,
 284                     children: m.items.iter().map(|i| id_from_node_id(i.id, self)).collect(),
 285                     decl_id: None,
 286                     docs: self.docs_for_attrs(&item.attrs),
 287                     sig: sig::item_signature(item, self),
 288                     attributes: lower_attributes(item.attrs.clone(), self),
 289                 }))
 290             }
 291             ast::ItemKind::Enum(ref def, _) => {
 292                 let name = item.ident.to_string();
 293                 let qualname = format!(
 294                     "::{}",
 295                     self.tcx.def_path_str(
 296                         self.tcx.hir().local_def_id_from_node_id(item.id).to_def_id()
 297                     )
 298                 );
 299                 filter!(self.span_utils, item.ident.span);
 300                 let variants_str =
 301                     def.variants.iter().map(|v| v.ident.to_string()).collect::<Vec<_>>().join(", ");
 302                 let value = format!("{}::{{{}}}", name, variants_str);
 303                 Some(Data::DefData(Def {
 304                     kind: DefKind::Enum,
 305                     id: id_from_node_id(item.id, self),
 306                     span: self.span_from_span(item.ident.span),
 307                     name,
 308                     qualname,
 309                     value,
 310                     parent: None,
 311                     children: def.variants.iter().map(|v| id_from_node_id(v.id, self)).collect(),
 312                     decl_id: None,
 313                     docs: self.docs_for_attrs(&item.attrs),
 314                     sig: sig::item_signature(item, self),
 315                     attributes: lower_attributes(item.attrs.clone(), self),
 316                 }))
 317             }
 318             ast::ItemKind::Impl { ref of_trait, ref self_ty, ref items, .. } => {
 319                 if let ast::TyKind::Path(None, ref path) = self_ty.kind {
 320                     // Common case impl for a struct or something basic.
 321                     if generated_code(path.span) {
 322                         return None;
 323                     }
 324                     let sub_span = path.segments.last().unwrap().ident.span;
 325                     filter!(self.span_utils, sub_span);
 326
 327                     let impl_id = self.next_impl_id();
 328                     let span = self.span_from_span(sub_span);
 329
 330                     let type_data = self.lookup_def_id(self_ty.id);
 331                     type_data.map(|type_data| {
 332                         Data::RelationData(
 333                             Relation {
 334                                 kind: RelationKind::Impl { id: impl_id },
 335                                 span: span.clone(),
 336                                 from: id_from_def_id(type_data),
 337                                 to: of_trait
 338                                     .as_ref()
 339                                     .and_then(|t| self.lookup_def_id(t.ref_id))
 340                                     .map(id_from_def_id)
 341                                     .unwrap_or_else(null_id),
 342                             },
 343                             Impl {
 344                                 id: impl_id,
 345                                 kind: match *of_trait {
 346                                     Some(_) => ImplKind::Direct,
 347                                     None => ImplKind::Inherent,
 348                                 },
 349                                 span,
 350                                 value: String::new(),
 351                                 parent: None,
 352                                 children: items
 353                                     .iter()
 354                                     .map(|i| id_from_node_id(i.id, self))
 355                                     .collect(),
 356                                 docs: String::new(),
 357                                 sig: None,
 358                                 attributes: vec![],
 359                             },
 360                         )
 361                     })
 362                 } else {
 363                     None
 364                 }
 365             }
 366             _ => {
 367                 // FIXME
 368                 bug!();
 369             }
 370         }
 371     }
 372
 373     pub fn get_field_data(&self, field: &ast::StructField, scope: NodeId) -> Option<Def> {
 374         if let Some(ident) = field.ident {
 375             let name = ident.to_string();
 376             let qualname = format!(
 377                 "::{}::{}",
 378                 self.tcx.def_path_str(self.tcx.hir().local_def_id_from_node_id(scope).to_def_id()),
 379                 ident
 380             );
 381             filter!(self.span_utils, ident.span);
 382             let def_id = self.tcx.hir().local_def_id_from_node_id(field.id).to_def_id();
 383             let typ = self.tcx.type_of(def_id).to_string();
 384
 385             let id = id_from_node_id(field.id, self);
 386             let span = self.span_from_span(ident.span);
 387
 388             Some(Def {
 389                 kind: DefKind::Field,
 390                 id,
 391                 span,
 392                 name,
 393                 qualname,
 394                 value: typ,
 395                 parent: Some(id_from_node_id(scope, self)),
 396                 children: vec![],
 397                 decl_id: None,
 398                 docs: self.docs_for_attrs(&field.attrs),
 399                 sig: sig::field_signature(field, self),
 400                 attributes: lower_attributes(field.attrs.clone(), self),
 401             })
 402         } else {
 403             None
 404         }
 405     }
 406
 407     // FIXME would be nice to take a MethodItem here, but the ast provides both
 408     // trait and impl flavours, so the caller must do the disassembly.
 409     pub fn get_method_data(&self, id: ast::NodeId, ident: Ident, span: Span) -> Option<Def> {
 410         // The qualname for a method is the trait name or name of the struct in an impl in
 411         // which the method is declared in, followed by the method's name.
 412         let (qualname, parent_scope, decl_id, docs, attributes) = match self
 413             .tcx
 414             .impl_of_method(self.tcx.hir().local_def_id_from_node_id(id).to_def_id())
 415         {
 416             Some(impl_id) => match self.tcx.hir().get_if_local(impl_id) {
 417                 Some(Node::Item(item)) => match item.kind {
 418                     hir::ItemKind::Impl { ref self_ty, .. } => {
 419                         let hir = self.tcx.hir();
 420
 421                         let mut qualname = String::from("<");
 422                         qualname.push_str(&rustc_hir_pretty::id_to_string(&hir, self_ty.hir_id));
 423
 424                         let trait_id = self.tcx.trait_id_of_impl(impl_id);
 425                         let mut docs = String::new();
 426                         let mut attrs = vec![];
 427                         if let Some(Node::ImplItem(item)) = hir.find(hir.node_id_to_hir_id(id)) {
 428                             docs = self.docs_for_attrs(&item.attrs);
 429                             attrs = item.attrs.to_vec();
 430                         }
 431
 432                         let mut decl_id = None;
 433                         if let Some(def_id) = trait_id {
 434                             // A method in a trait impl.
 435                             qualname.push_str(" as ");
 436                             qualname.push_str(&self.tcx.def_path_str(def_id));
 437
 438                             decl_id = self
 439                                 .tcx
 440                                 .associated_items(def_id)
 441                                 .filter_by_name_unhygienic(ident.name)
 442                                 .next()
 443                                 .map(|item| item.def_id);
 444                         }
 445                         qualname.push_str(">");
 446
 447                         (qualname, trait_id, decl_id, docs, attrs)
 448                     }
 449                     _ => {
 450                         span_bug!(span, "Container {:?} for method {} not an impl?", impl_id, id);
 451                     }
 452                 },
 453                 r => {
 454                     span_bug!(
 455                         span,
 456                         "Container {:?} for method {} is not a node item {:?}",
 457                         impl_id,
 458                         id,
 459                         r
 460                     );
 461                 }
 462             },
 463             None => match self
 464                 .tcx
 465                 .trait_of_item(self.tcx.hir().local_def_id_from_node_id(id).to_def_id())
 466             {
 467                 Some(def_id) => {
 468                     let mut docs = String::new();
 469                     let mut attrs = vec![];
 470                     let hir_id = self.tcx.hir().node_id_to_hir_id(id);
 471
 472                     if let Some(Node::TraitItem(item)) = self.tcx.hir().find(hir_id) {
 473                         docs = self.docs_for_attrs(&item.attrs);
 474                         attrs = item.attrs.to_vec();
 475                     }
 476
 477                     (
 478                         format!("::{}", self.tcx.def_path_str(def_id)),
 479                         Some(def_id),
 480                         None,
 481                         docs,
 482                         attrs,
 483                     )
 484                 }
 485                 None => {
 486                     debug!("could not find container for method {} at {:?}", id, span);
 487                     // This is not necessarily a bug, if there was a compilation error,
 488                     // the tables we need might not exist.
 489                     return None;
 490                 }
 491             },
 492         };
 493
 494         let qualname = format!("{}::{}", qualname, ident.name);
 495
 496         filter!(self.span_utils, ident.span);
 497
 498         Some(Def {
 499             kind: DefKind::Method,
 500             id: id_from_node_id(id, self),
 501             span: self.span_from_span(ident.span),
 502             name: ident.name.to_string(),
 503             qualname,
 504             // FIXME you get better data here by using the visitor.
 505             value: String::new(),
 506             parent: parent_scope.map(id_from_def_id),
 507             children: vec![],
 508             decl_id: decl_id.map(id_from_def_id),
 509             docs,
 510             sig: None,
 511             attributes: lower_attributes(attributes, self),
 512         })
 513     }
 514
 515     pub fn get_trait_ref_data(&self, trait_ref: &ast::TraitRef) -> Option<Ref> {
 516         self.lookup_def_id(trait_ref.ref_id).and_then(|def_id| {
 517             let span = trait_ref.path.span;
 518             if generated_code(span) {
 519                 return None;
 520             }
 521             let sub_span = trait_ref.path.segments.last().unwrap().ident.span;
 522             filter!(self.span_utils, sub_span);
 523             let span = self.span_from_span(sub_span);
 524             Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(def_id) })
 525         })
 526     }
 527
 528     pub fn get_expr_data(&self, expr: &ast::Expr) -> Option<Data> {
 529         let expr_hir_id = self.tcx.hir().node_id_to_hir_id(expr.id);
 530         let hir_node = self.tcx.hir().expect_expr(expr_hir_id);
 531         let ty = self.tables.expr_ty_adjusted_opt(&hir_node);
 532         if ty.is_none() || ty.unwrap().kind == ty::Error {
 533             return None;
 534         }
 535         match expr.kind {
 536             ast::ExprKind::Field(ref sub_ex, ident) => {
 537                 let sub_ex_hir_id = self.tcx.hir().node_id_to_hir_id(sub_ex.id);
 538                 let hir_node = match self.tcx.hir().find(sub_ex_hir_id) {
 539                     Some(Node::Expr(expr)) => expr,
 540                     _ => {
 541                         debug!(
 542                             "Missing or weird node for sub-expression {} in {:?}",
 543                             sub_ex.id, expr
 544                         );
 545                         return None;
 546                     }
 547                 };
 548                 match self.tables.expr_ty_adjusted(&hir_node).kind {
 549                     ty::Adt(def, _) if !def.is_enum() => {
 550                         let variant = &def.non_enum_variant();
 551                         filter!(self.span_utils, ident.span);
 552                         let span = self.span_from_span(ident.span);
 553                         Some(Data::RefData(Ref {
 554                             kind: RefKind::Variable,
 555                             span,
 556                             ref_id: self
 557                                 .tcx
 558                                 .find_field_index(ident, variant)
 559                                 .map(|index| id_from_def_id(variant.fields[index].did))
 560                                 .unwrap_or_else(null_id),
 561                         }))
 562                     }
 563                     ty::Tuple(..) => None,
 564                     _ => {
 565                         debug!("expected struct or union type, found {:?}", ty);
 566                         None
 567                     }
 568                 }
 569             }
 570             ast::ExprKind::Struct(ref path, ..) => {
 571                 match self.tables.expr_ty_adjusted(&hir_node).kind {
 572                     ty::Adt(def, _) if !def.is_enum() => {
 573                         let sub_span = path.segments.last().unwrap().ident.span;
 574                         filter!(self.span_utils, sub_span);
 575                         let span = self.span_from_span(sub_span);
 576                         Some(Data::RefData(Ref {
 577                             kind: RefKind::Type,
 578                             span,
 579                             ref_id: id_from_def_id(def.did),
 580                         }))
 581                     }
 582                     _ => {
 583                         // FIXME ty could legitimately be an enum, but then we will fail
 584                         // later if we try to look up the fields.
 585                         debug!("expected struct or union, found {:?}", ty);
 586                         None
 587                     }
 588                 }
 589             }
 590             ast::ExprKind::MethodCall(ref seg, ..) => {
 591                 let expr_hir_id = self.tcx.hir().definitions().node_id_to_hir_id(expr.id);
 592                 let method_id = match self.tables.type_dependent_def_id(expr_hir_id) {
 593                     Some(id) => id,
 594                     None => {
 595                         debug!("could not resolve method id for {:?}", expr);
 596                         return None;
 597                     }
 598                 };
 599                 let (def_id, decl_id) = match self.tcx.associated_item(method_id).container {
 600                     ty::ImplContainer(_) => (Some(method_id), None),
 601                     ty::TraitContainer(_) => (None, Some(method_id)),
 602                 };
 603                 let sub_span = seg.ident.span;
 604                 filter!(self.span_utils, sub_span);
 605                 let span = self.span_from_span(sub_span);
 606                 Some(Data::RefData(Ref {
 607                     kind: RefKind::Function,
 608                     span,
 609                     ref_id: def_id.or(decl_id).map(id_from_def_id).unwrap_or_else(null_id),
 610                 }))
 611             }
 612             ast::ExprKind::Path(_, ref path) => {
 613                 self.get_path_data(expr.id, path).map(Data::RefData)
 614             }
 615             _ => {
 616                 // FIXME
 617                 bug!();
 618             }
 619         }
 620     }
 621
 622     pub fn get_path_res(&self, id: NodeId) -> Res {
 623         // FIXME(#71104)
 624         let hir_id = match self.tcx.hir().opt_node_id_to_hir_id(id) {
 625             Some(id) => id,
 626             None => return Res::Err,
 627         };
 628         match self.tcx.hir().get(hir_id) {
 629             Node::TraitRef(tr) => tr.path.res,
 630
 631             Node::Item(&hir::Item { kind: hir::ItemKind::Use(path, _), .. }) => path.res,
 632             Node::Visibility(&Spanned {
 633                 node: hir::VisibilityKind::Restricted { ref path, .. },
 634                 ..
 635             }) => path.res,
 636
 637             Node::PathSegment(seg) => match seg.res {
 638                 Some(res) if res != Res::Err => res,
 639                 _ => {
 640                     let parent_node = self.tcx.hir().get_parent_node(hir_id);
 641                     self.get_path_res(self.tcx.hir().hir_id_to_node_id(parent_node))
 642                 }
 643             },
 644
 645             Node::Expr(&hir::Expr { kind: hir::ExprKind::Struct(ref qpath, ..), .. }) => {
 646                 self.tables.qpath_res(qpath, hir_id)
 647             }
 648
 649             Node::Expr(&hir::Expr { kind: hir::ExprKind::Path(ref qpath), .. })
 650             | Node::Pat(&hir::Pat {
 651                 kind:
 652                     hir::PatKind::Path(ref qpath)
 653                     | hir::PatKind::Struct(ref qpath, ..)
 654                     | hir::PatKind::TupleStruct(ref qpath, ..),
 655                 ..
 656             })
 657             | Node::Ty(&hir::Ty { kind: hir::TyKind::Path(ref qpath), .. }) => {
 658                 self.tables.qpath_res(qpath, hir_id)
 659             }
 660
 661             Node::Binding(&hir::Pat {
 662                 kind: hir::PatKind::Binding(_, canonical_id, ..), ..
 663             }) => Res::Local(canonical_id),
 664
 665             _ => Res::Err,
 666         }
 667     }
 668
 669     pub fn get_path_data(&self, id: NodeId, path: &ast::Path) -> Option<Ref> {
 670         path.segments.last().and_then(|seg| {
 671             self.get_path_segment_data(seg).or_else(|| self.get_path_segment_data_with_id(seg, id))
 672         })
 673     }
 674
 675     pub fn get_path_segment_data(&self, path_seg: &ast::PathSegment) -> Option<Ref> {
 676         self.get_path_segment_data_with_id(path_seg, path_seg.id)
 677     }
 678
 679     fn get_path_segment_data_with_id(
 680         &self,
 681         path_seg: &ast::PathSegment,
 682         id: NodeId,
 683     ) -> Option<Ref> {
 684         // Returns true if the path is function type sugar, e.g., `Fn(A) -> B`.
 685         fn fn_type(seg: &ast::PathSegment) -> bool {
 686             if let Some(ref generic_args) = seg.args {
 687                 if let ast::GenericArgs::Parenthesized(_) = **generic_args {
 688                     return true;
 689                 }
 690             }
 691             false
 692         }
 693
 694         if id == DUMMY_NODE_ID {
 695             return None;
 696         }
 697
 698         let res = self.get_path_res(id);
 699         let span = path_seg.ident.span;
 700         filter!(self.span_utils, span);
 701         let span = self.span_from_span(span);
 702
 703         match res {
 704             Res::Local(id) => Some(Ref {
 705                 kind: RefKind::Variable,
 706                 span,
 707                 ref_id: id_from_node_id(self.tcx.hir().hir_id_to_node_id(id), self),
 708             }),
 709             Res::Def(HirDefKind::Trait, def_id) if fn_type(path_seg) => {
 710                 Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(def_id) })
 711             }
 712             Res::Def(
 713                 HirDefKind::Struct
 714                 | HirDefKind::Variant
 715                 | HirDefKind::Union
 716                 | HirDefKind::Enum
 717                 | HirDefKind::TyAlias
 718                 | HirDefKind::ForeignTy
 719                 | HirDefKind::TraitAlias
 720                 | HirDefKind::AssocOpaqueTy
 721                 | HirDefKind::AssocTy
 722                 | HirDefKind::Trait
 723                 | HirDefKind::OpaqueTy
 724                 | HirDefKind::TyParam,
 725                 def_id,
 726             ) => Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(def_id) }),
 727             Res::Def(HirDefKind::ConstParam, def_id) => {
 728                 Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(def_id) })
 729             }
 730             Res::Def(HirDefKind::Ctor(CtorOf::Struct, ..), def_id) => {
 731                 // This is a reference to a tuple struct where the def_id points
 732                 // to an invisible constructor function. That is not a very useful
 733                 // def, so adjust to point to the tuple struct itself.
 734                 let parent_def_id = self.tcx.parent(def_id).unwrap();
 735                 Some(Ref { kind: RefKind::Type, span, ref_id: id_from_def_id(parent_def_id) })
 736             }
 737             Res::Def(
 738                 HirDefKind::Static
 739                 | HirDefKind::Const
 740                 | HirDefKind::AssocConst
 741                 | HirDefKind::Ctor(..),
 742                 _,
 743             ) => Some(Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(res.def_id()) }),
 744             Res::Def(HirDefKind::AssocFn, decl_id) => {
 745                 let def_id = if decl_id.is_local() {
 746                     let ti = self.tcx.associated_item(decl_id);
 747
 748                     self.tcx
 749                         .associated_items(ti.container.id())
 750                         .filter_by_name_unhygienic(ti.ident.name)
 751                         .find(|item| item.defaultness.has_value())
 752                         .map(|item| item.def_id)
 753                 } else {
 754                     None
 755                 };
 756                 Some(Ref {
 757                     kind: RefKind::Function,
 758                     span,
 759                     ref_id: id_from_def_id(def_id.unwrap_or(decl_id)),
 760                 })
 761             }
 762             Res::Def(HirDefKind::Fn, def_id) => {
 763                 Some(Ref { kind: RefKind::Function, span, ref_id: id_from_def_id(def_id) })
 764             }
 765             Res::Def(HirDefKind::Mod, def_id) => {
 766                 Some(Ref { kind: RefKind::Mod, span, ref_id: id_from_def_id(def_id) })
 767             }
 768
 769             Res::Def(
 770                 HirDefKind::Macro(..)
 771                 | HirDefKind::ExternCrate
 772                 | HirDefKind::ForeignMod
 773                 | HirDefKind::LifetimeParam
 774                 | HirDefKind::AnonConst
 775                 | HirDefKind::Use
 776                 | HirDefKind::Field
 777                 | HirDefKind::GlobalAsm
 778                 | HirDefKind::Impl
 779                 | HirDefKind::Closure
 780                 | HirDefKind::Generator,
 781                 _,
 782             )
 783             | Res::PrimTy(..)
 784             | Res::SelfTy(..)
 785             | Res::ToolMod
 786             | Res::NonMacroAttr(..)
 787             | Res::SelfCtor(..)
 788             | Res::Err => None,
 789         }
 790     }
 791
 792     pub fn get_field_ref_data(
 793         &self,
 794         field_ref: &ast::Field,
 795         variant: &ty::VariantDef,
 796     ) -> Option<Ref> {
 797         filter!(self.span_utils, field_ref.ident.span);
 798         self.tcx.find_field_index(field_ref.ident, variant).map(|index| {
 799             let span = self.span_from_span(field_ref.ident.span);
 800             Ref { kind: RefKind::Variable, span, ref_id: id_from_def_id(variant.fields[index].did) }
 801         })
 802     }
 803
 804     /// Attempt to return MacroRef for any AST node.
 805     ///
 806     /// For a given piece of AST defined by the supplied Span and NodeId,
 807     /// returns `None` if the node is not macro-generated or the span is malformed,
 808     /// else uses the expansion callsite and callee to return some MacroRef.
 809     pub fn get_macro_use_data(&self, span: Span) -> Option<MacroRef> {
 810         if !generated_code(span) {
 811             return None;
 812         }
 813         // Note we take care to use the source callsite/callee, to handle
 814         // nested expansions and ensure we only generate data for source-visible
 815         // macro uses.
 816         let callsite = span.source_callsite();
 817         let callsite_span = self.span_from_span(callsite);
 818         let callee = span.source_callee()?;
 819
 820         let mac_name = match callee.kind {
 821             ExpnKind::Macro(mac_kind, name) => match mac_kind {
 822                 MacroKind::Bang => name,
 823
 824                 // Ignore attribute macros, their spans are usually mangled
 825                 // FIXME(eddyb) is this really the case anymore?
 826                 MacroKind::Attr | MacroKind::Derive => return None,
 827             },
 828
 829             // These are not macros.
 830             // FIXME(eddyb) maybe there is a way to handle them usefully?
 831             ExpnKind::Root | ExpnKind::AstPass(_) | ExpnKind::Desugaring(_) => return None,
 832         };
 833
 834         let callee_span = self.span_from_span(callee.def_site);
 835         Some(MacroRef {
 836             span: callsite_span,
 837             qualname: mac_name.to_string(), // FIXME: generate the real qualname
 838             callee_span,
 839         })
 840     }
 841
 842     fn lookup_def_id(&self, ref_id: NodeId) -> Option<DefId> {
 843         match self.get_path_res(ref_id) {
 844             Res::PrimTy(_) | Res::SelfTy(..) | Res::Err => None,
 845             def => def.opt_def_id(),
 846         }
 847     }
 848
 849     fn docs_for_attrs(&self, attrs: &[Attribute]) -> String {
 850         let mut result = String::new();
 851
 852         for attr in attrs {
 853             if let Some(val) = attr.doc_str() {
 854                 if attr.is_doc_comment() {
 855                     result.push_str(&strip_doc_comment_decoration(&val.as_str()));
 856                 } else {
 857                     result.push_str(&val.as_str());
 858                 }
 859                 result.push('\n');
 860             } else if attr.check_name(sym::doc) {
 861                 if let Some(meta_list) = attr.meta_item_list() {
 862                     meta_list
 863                         .into_iter()
 864                         .filter(|it| it.check_name(sym::include))
 865                         .filter_map(|it| it.meta_item_list().map(|l| l.to_owned()))
 866                         .flat_map(|it| it)
 867                         .filter(|meta| meta.check_name(sym::contents))
 868                         .filter_map(|meta| meta.value_str())
 869                         .for_each(|val| {
 870                             result.push_str(&val.as_str());
 871                             result.push('\n');
 872                         });
 873                 }
 874             }
 875         }
 876
 877         if !self.config.full_docs {
 878             if let Some(index) = result.find("\n\n") {
 879                 result.truncate(index);
 880             }
 881         }
 882
 883         result
 884     }
 885
 886     fn next_impl_id(&self) -> u32 {
 887         let next = self.impl_counter.get();
 888         self.impl_counter.set(next + 1);
 889         next
 890     }
 891 }
 892
 893 fn make_signature(decl: &ast::FnDecl, generics: &ast::Generics) -> String {
 894     let mut sig = "fn ".to_owned();
 895     if !generics.params.is_empty() {
 896         sig.push('<');
 897         sig.push_str(
 898             &generics
 899                 .params
 900                 .iter()
 901                 .map(|param| param.ident.to_string())
 902                 .collect::<Vec<_>>()
 903                 .join(", "),
 904         );
 905         sig.push_str("> ");
 906     }
 907     sig.push('(');
 908     sig.push_str(&decl.inputs.iter().map(param_to_string).collect::<Vec<_>>().join(", "));
 909     sig.push(')');
 910     match decl.output {
 911         ast::FnRetTy::Default(_) => sig.push_str(" -> ()"),
 912         ast::FnRetTy::Ty(ref t) => sig.push_str(&format!(" -> {}", ty_to_string(t))),
 913     }
 914
 915     sig
 916 }
 917
 918 // An AST visitor for collecting paths (e.g., the names of structs) and formal
 919 // variables (idents) from patterns.
 920 struct PathCollector<'l> {
 921     collected_paths: Vec<(NodeId, &'l ast::Path)>,
 922     collected_idents: Vec<(NodeId, Ident, ast::Mutability)>,
 923 }
 924
 925 impl<'l> PathCollector<'l> {
 926     fn new() -> PathCollector<'l> {
 927         PathCollector { collected_paths: vec![], collected_idents: vec![] }
 928     }
 929 }
 930
 931 impl<'l> Visitor<'l> for PathCollector<'l> {
 932     fn visit_pat(&mut self, p: &'l ast::Pat) {
 933         match p.kind {
 934             PatKind::Struct(ref path, ..) => {
 935                 self.collected_paths.push((p.id, path));
 936             }
 937             PatKind::TupleStruct(ref path, ..) | PatKind::Path(_, ref path) => {
 938                 self.collected_paths.push((p.id, path));
 939             }
 940             PatKind::Ident(bm, ident, _) => {
 941                 debug!(
 942                     "PathCollector, visit ident in pat {}: {:?} {:?}",
 943                     ident, p.span, ident.span
 944                 );
 945                 let immut = match bm {
 946                     // Even if the ref is mut, you can't change the ref, only
 947                     // the data pointed at, so showing the initialising expression
 948                     // is still worthwhile.
 949                     ast::BindingMode::ByRef(_) => ast::Mutability::Not,
 950                     ast::BindingMode::ByValue(mt) => mt,
 951                 };
 952                 self.collected_idents.push((p.id, ident, immut));
 953             }
 954             _ => {}
 955         }
 956         visit::walk_pat(self, p);
 957     }
 958 }
 959
 960 /// Defines what to do with the results of saving the analysis.
 961 pub trait SaveHandler {
 962     fn save(&mut self, save_ctxt: &SaveContext<'_, '_>, analysis: &Analysis);
 963 }
 964
 965 /// Dump the save-analysis results to a file.
 966 pub struct DumpHandler<'a> {
 967     odir: Option<&'a Path>,
 968     cratename: String,
 969 }
 970
 971 impl<'a> DumpHandler<'a> {
 972     pub fn new(odir: Option<&'a Path>, cratename: &str) -> DumpHandler<'a> {
 973         DumpHandler { odir, cratename: cratename.to_owned() }
 974     }
 975
 976     fn output_file(&self, ctx: &SaveContext<'_, '_>) -> (BufWriter<File>, PathBuf) {
 977         let sess = &ctx.tcx.sess;
 978         let file_name = match ctx.config.output_file {
 979             Some(ref s) => PathBuf::from(s),
 980             None => {
 981                 let mut root_path = match self.odir {
 982                     Some(val) => val.join("save-analysis"),
 983                     None => PathBuf::from("save-analysis-temp"),
 984                 };
 985
 986                 if let Err(e) = std::fs::create_dir_all(&root_path) {
 987                     error!("Could not create directory {}: {}", root_path.display(), e);
 988                 }
 989
 990                 let executable = sess.crate_types().iter().any(|ct| *ct == CrateType::Executable);
 991                 let mut out_name = if executable { String::new() } else { "lib".to_owned() };
 992                 out_name.push_str(&self.cratename);
 993                 out_name.push_str(&sess.opts.cg.extra_filename);
 994                 out_name.push_str(".json");
 995                 root_path.push(&out_name);
 996
 997                 root_path
 998             }
 999         };
1000
1001         info!("Writing output to {}", file_name.display());
1002
1003         let output_file = BufWriter::new(File::create(&file_name).unwrap_or_else(|e| {
1004             sess.fatal(&format!("Could not open {}: {}", file_name.display(), e))
1005         }));
1006
1007         (output_file, file_name)
1008     }
1009 }
1010
1011 impl SaveHandler for DumpHandler<'_> {
1012     fn save(&mut self, save_ctxt: &SaveContext<'_, '_>, analysis: &Analysis) {
1013         let sess = &save_ctxt.tcx.sess;
1014         let (output, file_name) = self.output_file(&save_ctxt);
1015         if let Err(e) = serde_json::to_writer(output, &analysis) {
1016             error!("Can't serialize save-analysis: {:?}", e);
1017         }
1018
1019         if sess.opts.json_artifact_notifications {
1020             sess.parse_sess.span_diagnostic.emit_artifact_notification(&file_name, "save-analysis");
1021         }
1022     }
1023 }
1024
1025 /// Call a callback with the results of save-analysis.
1026 pub struct CallbackHandler<'b> {
1027     pub callback: &'b mut dyn FnMut(&rls_data::Analysis),
1028 }
1029
1030 impl SaveHandler for CallbackHandler<'_> {
1031     fn save(&mut self, _: &SaveContext<'_, '_>, analysis: &Analysis) {
1032         (self.callback)(analysis)
1033     }
1034 }
1035
1036 pub fn process_crate<'l, 'tcx, H: SaveHandler>(
1037     tcx: TyCtxt<'tcx>,
1038     krate: &ast::Crate,
1039     cratename: &str,
1040     input: &'l Input,
1041     config: Option<Config>,
1042     mut handler: H,
1043 ) {
1044     tcx.dep_graph.with_ignore(|| {
1045         info!("Dumping crate {}", cratename);
1046
1047         // Privacy checking requires and is done after type checking; use a
1048         // fallback in case the access levels couldn't have been correctly computed.
1049         let access_levels = match tcx.sess.compile_status() {
1050             Ok(..) => tcx.privacy_access_levels(LOCAL_CRATE),
1051             Err(..) => tcx.arena.alloc(AccessLevels::default()),
1052         };
1053
1054         let save_ctxt = SaveContext {
1055             tcx,
1056             tables: &ty::TypeckTables::empty(None),
1057             empty_tables: &ty::TypeckTables::empty(None),
1058             access_levels: &access_levels,
1059             span_utils: SpanUtils::new(&tcx.sess),
1060             config: find_config(config),
1061             impl_counter: Cell::new(0),
1062         };
1063
1064         let mut visitor = DumpVisitor::new(save_ctxt);
1065
1066         visitor.dump_crate_info(cratename, krate);
1067         visitor.dump_compilation_options(input, cratename);
1068         visit::walk_crate(&mut visitor, krate);
1069
1070         handler.save(&visitor.save_ctxt, &visitor.analysis())
1071     })
1072 }
1073
1074 fn find_config(supplied: Option<Config>) -> Config {
1075     if let Some(config) = supplied {
1076         return config;
1077     }
1078
1079     match env::var_os("RUST_SAVE_ANALYSIS_CONFIG") {
1080         None => Config::default(),
1081         Some(config) => config
1082             .to_str()
1083             .ok_or(())
1084             .map_err(|_| error!("`RUST_SAVE_ANALYSIS_CONFIG` isn't UTF-8"))
1085             .and_then(|cfg| {
1086                 serde_json::from_str(cfg)
1087                     .map_err(|_| error!("Could not deserialize save-analysis config"))
1088             })
1089             .unwrap_or_default(),
1090     }
1091 }
1092
1093 // Utility functions for the module.
1094
1095 // Helper function to escape quotes in a string
1096 fn escape(s: String) -> String {
1097     s.replace("\"", "\"\"")
1098 }
1099
1100 // Helper function to determine if a span came from a
1101 // macro expansion or syntax extension.
1102 fn generated_code(span: Span) -> bool {
1103     span.from_expansion() || span.is_dummy()
1104 }
1105
1106 // DefId::index is a newtype and so the JSON serialisation is ugly. Therefore
1107 // we use our own Id which is the same, but without the newtype.
1108 fn id_from_def_id(id: DefId) -> rls_data::Id {
1109     rls_data::Id { krate: id.krate.as_u32(), index: id.index.as_u32() }
1110 }
1111
1112 fn id_from_node_id(id: NodeId, scx: &SaveContext<'_, '_>) -> rls_data::Id {
1113     let def_id = scx.tcx.hir().opt_local_def_id_from_node_id(id);
1114     def_id.map(|id| id_from_def_id(id.to_def_id())).unwrap_or_else(|| {
1115         // Create a *fake* `DefId` out of a `NodeId` by subtracting the `NodeId`
1116         // out of the maximum u32 value. This will work unless you have *billions*
1117         // of definitions in a single crate (very unlikely to actually happen).
1118         rls_data::Id { krate: LOCAL_CRATE.as_u32(), index: !id.as_u32() }
1119     })
1120 }
1121
1122 fn null_id() -> rls_data::Id {
1123     rls_data::Id { krate: u32::max_value(), index: u32::max_value() }
1124 }
1125
1126 fn lower_attributes(attrs: Vec<Attribute>, scx: &SaveContext<'_, '_>) -> Vec<rls_data::Attribute> {
1127     attrs
1128         .into_iter()
1129         // Only retain real attributes. Doc comments are lowered separately.
1130         .filter(|attr| !attr.has_name(sym::doc))
1131         .map(|mut attr| {
1132             // Remove the surrounding '#[..]' or '#![..]' of the pretty printed
1133             // attribute. First normalize all inner attribute (#![..]) to outer
1134             // ones (#[..]), then remove the two leading and the one trailing character.
1135             attr.style = ast::AttrStyle::Outer;
1136             let value = pprust::attribute_to_string(&attr);
1137             // This str slicing works correctly, because the leading and trailing characters
1138             // are in the ASCII range and thus exactly one byte each.
1139             let value = value[2..value.len() - 1].to_string();
1140
1141             rls_data::Attribute { value, span: scx.span_from_span(attr.span) }
1142         })
1143         .collect()
1144 }