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1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
4 //
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
10
11 #![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png",
12        html_favicon_url = "https://doc.rust-lang.org/favicon.ico",
13        html_root_url = "https://doc.rust-lang.org/nightly/")]
14 #![feature(custom_attribute)]
15 #![feature(macro_lifetime_matcher)]
16 #![allow(unused_attributes)]
17
18 #[macro_use]
19 extern crate rustc;
20
21 #[macro_use]
22 extern crate log;
23 extern crate rustc_data_structures;
24 extern crate rustc_serialize;
25 extern crate rustc_target;
26 extern crate rustc_typeck;
27 #[macro_use]
28 extern crate syntax;
29 extern crate syntax_pos;
30
31 extern crate rls_data;
32 extern crate rls_span;
33
34
35 mod json_dumper;
36 mod dump_visitor;
37 #[macro_use]
38 mod span_utils;
39 mod sig;
40
41 use rustc::hir;
42 use rustc::hir::def::Def as HirDef;
43 use rustc::hir::map::{Node, NodeItem};
44 use rustc::hir::def_id::{DefId, LOCAL_CRATE};
45 use rustc::middle::cstore::ExternCrate;
46 use rustc::session::config::CrateType::CrateTypeExecutable;
47 use rustc::ty::{self, TyCtxt};
48 use rustc_typeck::hir_ty_to_ty;
49
50 use std::cell::Cell;
51 use std::default::Default;
52 use std::env;
53 use std::fs::File;
54 use std::path::{Path, PathBuf};
55
56 use syntax::ast::{self, Attribute, NodeId, PatKind};
57 use syntax::parse::lexer::comments::strip_doc_comment_decoration;
58 use syntax::parse::token;
59 use syntax::print::pprust;
60 use syntax::symbol::keywords;
61 use syntax::visit::{self, Visitor};
62 use syntax::print::pprust::{arg_to_string, ty_to_string};
63 use syntax::codemap::MacroAttribute;
64 use syntax_pos::*;
65
66 use json_dumper::JsonDumper;
67 use dump_visitor::DumpVisitor;
68 use span_utils::SpanUtils;
69
70 use rls_data::{Def, DefKind, ExternalCrateData, GlobalCrateId, MacroRef, Ref, RefKind, Relation,
71                RelationKind, SpanData, Impl, ImplKind};
72 use rls_data::config::Config;
73
74
75 pub struct SaveContext<'l, 'tcx: 'l> {
76     tcx: TyCtxt<'l, 'tcx, 'tcx>,
77     tables: &'l ty::TypeckTables<'tcx>,
78     analysis: &'l ty::CrateAnalysis,
79     span_utils: SpanUtils<'tcx>,
80     config: Config,
81     impl_counter: Cell<u32>,
82 }
83
84 #[derive(Debug)]
85 pub enum Data {
86     RefData(Ref),
87     DefData(Def),
88     RelationData(Relation, Impl),
89 }
90
91 impl<'l, 'tcx: 'l> SaveContext<'l, 'tcx> {
92     fn span_from_span(&self, span: Span) -> SpanData {
93         use rls_span::{Column, Row};
94
95         let cm = self.tcx.sess.codemap();
96         let start = cm.lookup_char_pos(span.lo());
97         let end = cm.lookup_char_pos(span.hi());
98
99         SpanData {
100             file_name: start.file.name.clone().to_string().into(),
101             byte_start: span.lo().0,
102             byte_end: span.hi().0,
103             line_start: Row::new_one_indexed(start.line as u32),
104             line_end: Row::new_one_indexed(end.line as u32),
105             column_start: Column::new_one_indexed(start.col.0 as u32 + 1),
106             column_end: Column::new_one_indexed(end.col.0 as u32 + 1),
107         }
108     }
109
110     // List external crates used by the current crate.
111     pub fn get_external_crates(&self) -> Vec<ExternalCrateData> {
112         let mut result = Vec::new();
113
114         for &n in self.tcx.crates().iter() {
115             let span = match *self.tcx.extern_crate(n.as_def_id()) {
116                 Some(ExternCrate { span, .. }) => span,
117                 None => {
118                     debug!("Skipping crate {}, no data", n);
119                     continue;
120                 }
121             };
122             let lo_loc = self.span_utils.sess.codemap().lookup_char_pos(span.lo());
123             result.push(ExternalCrateData {
124                 // FIXME: change file_name field to PathBuf in rls-data
125                 // https://github.com/nrc/rls-data/issues/7
126                 file_name: SpanUtils::make_path_string(&lo_loc.file.name),
127                 num: n.as_u32(),
128                 id: GlobalCrateId {
129                     name: self.tcx.crate_name(n).to_string(),
130                     disambiguator: self.tcx.crate_disambiguator(n).to_fingerprint().as_value(),
131                 },
132             });
133         }
134
135         result
136     }
137
138     pub fn get_extern_item_data(&self, item: &ast::ForeignItem) -> Option<Data> {
139         let qualname = format!("::{}", self.tcx.node_path_str(item.id));
140         match item.node {
141             ast::ForeignItemKind::Fn(ref decl, ref generics) => {
142                 let sub_span = self.span_utils
143                     .sub_span_after_keyword(item.span, keywords::Fn);
144                 filter!(self.span_utils, sub_span, item.span, None);
145
146                 Some(Data::DefData(Def {
147                     kind: DefKind::Function,
148                     id: id_from_node_id(item.id, self),
149                     span: self.span_from_span(sub_span.unwrap()),
150                     name: item.ident.to_string(),
151                     qualname,
152                     value: make_signature(decl, generics),
153                     parent: None,
154                     children: vec![],
155                     decl_id: None,
156                     docs: self.docs_for_attrs(&item.attrs),
157                     sig: sig::foreign_item_signature(item, self),
158                     attributes: lower_attributes(item.attrs.clone(), self),
159                 }))
160             }
161             ast::ForeignItemKind::Static(ref ty, m) => {
162                 let keyword = if m { keywords::Mut } else { keywords::Static };
163                 let sub_span = self.span_utils.sub_span_after_keyword(item.span, keyword);
164                 filter!(self.span_utils, sub_span, item.span, None);
165
166                 let id = ::id_from_node_id(item.id, self);
167                 let span = self.span_from_span(sub_span.unwrap());
168
169                 Some(Data::DefData(Def {
170                     kind: DefKind::Static,
171                     id,
172                     span,
173                     name: item.ident.to_string(),
174                     qualname,
175                     value: ty_to_string(ty),
176                     parent: None,
177                     children: vec![],
178                     decl_id: None,
179                     docs: self.docs_for_attrs(&item.attrs),
180                     sig: sig::foreign_item_signature(item, self),
181                     attributes: lower_attributes(item.attrs.clone(), self),
182                 }))
183             }
184             // FIXME(plietar): needs a new DefKind in rls-data
185             ast::ForeignItemKind::Ty => None,
186             ast::ForeignItemKind::Macro(..) => None,
187         }
188     }
189
190     pub fn get_item_data(&self, item: &ast::Item) -> Option<Data> {
191         match item.node {
192             ast::ItemKind::Fn(ref decl, .., ref generics, _) => {
193                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
194                 let sub_span = self.span_utils
195                     .sub_span_after_keyword(item.span, keywords::Fn);
196                 filter!(self.span_utils, sub_span, item.span, None);
197                 Some(Data::DefData(Def {
198                     kind: DefKind::Function,
199                     id: id_from_node_id(item.id, self),
200                     span: self.span_from_span(sub_span.unwrap()),
201                     name: item.ident.to_string(),
202                     qualname,
203                     value: make_signature(decl, generics),
204                     parent: None,
205                     children: vec![],
206                     decl_id: None,
207                     docs: self.docs_for_attrs(&item.attrs),
208                     sig: sig::item_signature(item, self),
209                     attributes: lower_attributes(item.attrs.clone(), self),
210                 }))
211             }
212             ast::ItemKind::Static(ref typ, mt, _) => {
213                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
214
215                 let keyword = match mt {
216                     ast::Mutability::Mutable => keywords::Mut,
217                     ast::Mutability::Immutable => keywords::Static,
218                 };
219
220                 let sub_span = self.span_utils.sub_span_after_keyword(item.span, keyword);
221                 filter!(self.span_utils, sub_span, item.span, None);
222
223                 let id = id_from_node_id(item.id, self);
224                 let span = self.span_from_span(sub_span.unwrap());
225
226                 Some(Data::DefData(Def {
227                     kind: DefKind::Static,
228                     id,
229                     span,
230                     name: item.ident.to_string(),
231                     qualname,
232                     value: ty_to_string(&typ),
233                     parent: None,
234                     children: vec![],
235                     decl_id: None,
236                     docs: self.docs_for_attrs(&item.attrs),
237                     sig: sig::item_signature(item, self),
238                     attributes: lower_attributes(item.attrs.clone(), self),
239                 }))
240             }
241             ast::ItemKind::Const(ref typ, _) => {
242                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
243                 let sub_span = self.span_utils
244                     .sub_span_after_keyword(item.span, keywords::Const);
245                 filter!(self.span_utils, sub_span, item.span, None);
246
247                 let id = id_from_node_id(item.id, self);
248                 let span = self.span_from_span(sub_span.unwrap());
249
250                 Some(Data::DefData(Def {
251                     kind: DefKind::Const,
252                     id,
253                     span,
254                     name: item.ident.to_string(),
255                     qualname,
256                     value: ty_to_string(typ),
257                     parent: None,
258                     children: vec![],
259                     decl_id: None,
260                     docs: self.docs_for_attrs(&item.attrs),
261                     sig: sig::item_signature(item, self),
262                     attributes: lower_attributes(item.attrs.clone(), self),
263                 }))
264             }
265             ast::ItemKind::Mod(ref m) => {
266                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
267
268                 let cm = self.tcx.sess.codemap();
269                 let filename = cm.span_to_filename(m.inner);
270
271                 let sub_span = self.span_utils
272                     .sub_span_after_keyword(item.span, keywords::Mod);
273                 filter!(self.span_utils, sub_span, item.span, None);
274
275                 Some(Data::DefData(Def {
276                     kind: DefKind::Mod,
277                     id: id_from_node_id(item.id, self),
278                     name: item.ident.to_string(),
279                     qualname,
280                     span: self.span_from_span(sub_span.unwrap()),
281                     value: filename.to_string(),
282                     parent: None,
283                     children: m.items
284                         .iter()
285                         .map(|i| id_from_node_id(i.id, self))
286                         .collect(),
287                     decl_id: None,
288                     docs: self.docs_for_attrs(&item.attrs),
289                     sig: sig::item_signature(item, self),
290                     attributes: lower_attributes(item.attrs.clone(), self),
291                 }))
292             }
293             ast::ItemKind::Enum(ref def, _) => {
294                 let name = item.ident.to_string();
295                 let qualname = format!("::{}", self.tcx.node_path_str(item.id));
296                 let sub_span = self.span_utils
297                     .sub_span_after_keyword(item.span, keywords::Enum);
298                 filter!(self.span_utils, sub_span, item.span, None);
299                 let variants_str = def.variants
300                     .iter()
301                     .map(|v| v.node.ident.to_string())
302                     .collect::<Vec<_>>()
303                     .join(", ");
304                 let value = format!("{}::{{{}}}", name, variants_str);
305                 Some(Data::DefData(Def {
306                     kind: DefKind::Enum,
307                     id: id_from_node_id(item.id, self),
308                     span: self.span_from_span(sub_span.unwrap()),
309                     name,
310                     qualname,
311                     value,
312                     parent: None,
313                     children: def.variants
314                         .iter()
315                         .map(|v| id_from_node_id(v.node.data.id(), self))
316                         .collect(),
317                     decl_id: None,
318                     docs: self.docs_for_attrs(&item.attrs),
319                     sig: sig::item_signature(item, self),
320                     attributes: lower_attributes(item.attrs.to_owned(), self),
321                 }))
322             }
323             ast::ItemKind::Impl(.., ref trait_ref, ref typ, ref impls) => {
324                 if let ast::TyKind::Path(None, ref path) = typ.node {
325                     // Common case impl for a struct or something basic.
326                     if generated_code(path.span) {
327                         return None;
328                     }
329                     let sub_span = self.span_utils.sub_span_for_type_name(path.span);
330                     filter!(self.span_utils, sub_span, typ.span, None);
331
332                     let impl_id = self.next_impl_id();
333                     let span = self.span_from_span(sub_span.unwrap());
334
335                     let type_data = self.lookup_ref_id(typ.id);
336                     type_data.map(|type_data| {
337                         Data::RelationData(Relation {
338                             kind: RelationKind::Impl {
339                                 id: impl_id,
340                             },
341                             span: span.clone(),
342                             from: id_from_def_id(type_data),
343                             to: trait_ref
344                                 .as_ref()
345                                 .and_then(|t| self.lookup_ref_id(t.ref_id))
346                                 .map(id_from_def_id)
347                                 .unwrap_or(null_id()),
348                         },
349                         Impl {
350                             id: impl_id,
351                             kind: match *trait_ref {
352                                 Some(_) => ImplKind::Direct,
353                                 None => ImplKind::Inherent,
354                             },
355                             span: span,
356                             value: String::new(),
357                             parent: None,
358                             children: impls
359                                 .iter()
360                                 .map(|i| id_from_node_id(i.id, self))
361                                 .collect(),
362                             docs: String::new(),
363                             sig: None,
364                             attributes: vec![],
365                         })
366                     })
367                 } else {
368                     None
369                 }
370             }
371             _ => {
372                 // FIXME
373                 bug!();
374             }
375         }
376     }
377
378     pub fn get_field_data(&self, field: &ast::StructField, scope: NodeId) -> Option<Def> {
379         if let Some(ident) = field.ident {
380             let name = ident.to_string();
381             let qualname = format!("::{}::{}", self.tcx.node_path_str(scope), ident);
382             let sub_span = self.span_utils
383                 .sub_span_before_token(field.span, token::Colon);
384             filter!(self.span_utils, sub_span, field.span, None);
385             let def_id = self.tcx.hir.local_def_id(field.id);
386             let typ = self.tcx.type_of(def_id).to_string();
387
388
389             let id = id_from_node_id(field.id, self);
390             let span = self.span_from_span(sub_span.unwrap());
391
392             Some(Def {
393                 kind: DefKind::Field,
394                 id,
395                 span,
396                 name,
397                 qualname,
398                 value: typ,
399                 parent: Some(id_from_node_id(scope, self)),
400                 children: vec![],
401                 decl_id: None,
402                 docs: self.docs_for_attrs(&field.attrs),
403                 sig: sig::field_signature(field, self),
404                 attributes: lower_attributes(field.attrs.clone(), self),
405             })
406         } else {
407             None
408         }
409     }
410
411     // FIXME would be nice to take a MethodItem here, but the ast provides both
412     // trait and impl flavours, so the caller must do the disassembly.
413     pub fn get_method_data(&self, id: ast::NodeId, name: ast::Name, span: Span) -> Option<Def> {
414         // The qualname for a method is the trait name or name of the struct in an impl in
415         // which the method is declared in, followed by the method's name.
416         let (qualname, parent_scope, decl_id, docs, attributes) =
417             match self.tcx.impl_of_method(self.tcx.hir.local_def_id(id)) {
418                 Some(impl_id) => match self.tcx.hir.get_if_local(impl_id) {
419                     Some(Node::NodeItem(item)) => match item.node {
420                         hir::ItemImpl(.., ref ty, _) => {
421                             let mut result = String::from("<");
422                             result.push_str(&self.tcx.hir.node_to_pretty_string(ty.id));
423
424                             let mut trait_id = self.tcx.trait_id_of_impl(impl_id);
425                             let mut decl_id = None;
426                             if let Some(def_id) = trait_id {
427                                 result.push_str(" as ");
428                                 result.push_str(&self.tcx.item_path_str(def_id));
429                                 self.tcx
430                                     .associated_items(def_id)
431                                     .find(|item| item.name == name)
432                                     .map(|item| decl_id = Some(item.def_id));
433                             } else {
434                                 if let Some(NodeItem(item)) = self.tcx.hir.find(id) {
435                                     if let hir::ItemImpl(_, _, _, _, _, ref ty, _) = item.node {
436                                         trait_id = self.lookup_ref_id(ty.id);
437                                     }
438                                 }
439                             }
440                             result.push_str(">");
441
442                             (
443                                 result,
444                                 trait_id,
445                                 decl_id,
446                                 self.docs_for_attrs(&item.attrs),
447                                 item.attrs.to_vec(),
448                             )
449                         }
450                         _ => {
451                             span_bug!(
452                                 span,
453                                 "Container {:?} for method {} not an impl?",
454                                 impl_id,
455                                 id
456                             );
457                         }
458                     },
459                     r => {
460                         span_bug!(
461                             span,
462                             "Container {:?} for method {} is not a node item {:?}",
463                             impl_id,
464                             id,
465                             r
466                         );
467                     }
468                 },
469                 None => match self.tcx.trait_of_item(self.tcx.hir.local_def_id(id)) {
470                     Some(def_id) => match self.tcx.hir.get_if_local(def_id) {
471                         Some(Node::NodeItem(item)) => (
472                             format!("::{}", self.tcx.item_path_str(def_id)),
473                             Some(def_id),
474                             None,
475                             self.docs_for_attrs(&item.attrs),
476                             item.attrs.to_vec(),
477                         ),
478                         r => {
479                             span_bug!(
480                                 span,
481                                 "Could not find container {:?} for \
482                                  method {}, got {:?}",
483                                 def_id,
484                                 id,
485                                 r
486                             );
487                         }
488                     },
489                     None => {
490                         debug!("Could not find container for method {} at {:?}", id, span);
491                         // This is not necessarily a bug, if there was a compilation error,
492                         // the tables we need might not exist.
493                         return None;
494                     }
495                 },
496             };
497
498         let qualname = format!("{}::{}", qualname, name);
499
500         let sub_span = self.span_utils.sub_span_after_keyword(span, keywords::Fn);
501         filter!(self.span_utils, sub_span, span, None);
502
503         Some(Def {
504             kind: DefKind::Method,
505             id: id_from_node_id(id, self),
506             span: self.span_from_span(sub_span.unwrap()),
507             name: name.to_string(),
508             qualname,
509             // FIXME you get better data here by using the visitor.
510             value: String::new(),
511             parent: parent_scope.map(|id| id_from_def_id(id)),
512             children: vec![],
513             decl_id: decl_id.map(|id| id_from_def_id(id)),
514             docs,
515             sig: None,
516             attributes: lower_attributes(attributes, self),
517         })
518     }
519
520     pub fn get_trait_ref_data(&self, trait_ref: &ast::TraitRef) -> Option<Ref> {
521         self.lookup_ref_id(trait_ref.ref_id).and_then(|def_id| {
522             let span = trait_ref.path.span;
523             if generated_code(span) {
524                 return None;
525             }
526             let sub_span = self.span_utils.sub_span_for_type_name(span).or(Some(span));
527             filter!(self.span_utils, sub_span, span, None);
528             let span = self.span_from_span(sub_span.unwrap());
529             Some(Ref {
530                 kind: RefKind::Type,
531                 span,
532                 ref_id: id_from_def_id(def_id),
533             })
534         })
535     }
536
537     pub fn get_expr_data(&self, expr: &ast::Expr) -> Option<Data> {
538         let hir_node = self.tcx.hir.expect_expr(expr.id);
539         let ty = self.tables.expr_ty_adjusted_opt(&hir_node);
540         if ty.is_none() || ty.unwrap().sty == ty::TyError {
541             return None;
542         }
543         match expr.node {
544             ast::ExprKind::Field(ref sub_ex, ident) => {
545                 let hir_node = match self.tcx.hir.find(sub_ex.id) {
546                     Some(Node::NodeExpr(expr)) => expr,
547                     _ => {
548                         debug!(
549                             "Missing or weird node for sub-expression {} in {:?}",
550                             sub_ex.id,
551                             expr
552                         );
553                         return None;
554                     }
555                 };
556                 match self.tables.expr_ty_adjusted(&hir_node).sty {
557                     ty::TyAdt(def, _) if !def.is_enum() => {
558                         let variant = &def.non_enum_variant();
559                         let index = self.tcx.find_field_index(ident, variant).unwrap();
560                         let sub_span = self.span_utils.span_for_last_ident(expr.span);
561                         filter!(self.span_utils, sub_span, expr.span, None);
562                         let span = self.span_from_span(sub_span.unwrap());
563                         return Some(Data::RefData(Ref {
564                             kind: RefKind::Variable,
565                             span,
566                             ref_id: id_from_def_id(variant.fields[index].did),
567                         }));
568                     }
569                     ty::TyTuple(..) => None,
570                     _ => {
571                         debug!("Expected struct or union type, found {:?}", ty);
572                         None
573                     }
574                 }
575             }
576             ast::ExprKind::Struct(ref path, ..) => {
577                 match self.tables.expr_ty_adjusted(&hir_node).sty {
578                     ty::TyAdt(def, _) if !def.is_enum() => {
579                         let sub_span = self.span_utils.span_for_last_ident(path.span);
580                         filter!(self.span_utils, sub_span, path.span, None);
581                         let span = self.span_from_span(sub_span.unwrap());
582                         Some(Data::RefData(Ref {
583                             kind: RefKind::Type,
584                             span,
585                             ref_id: id_from_def_id(def.did),
586                         }))
587                     }
588                     _ => {
589                         // FIXME ty could legitimately be an enum, but then we will fail
590                         // later if we try to look up the fields.
591                         debug!("expected struct or union, found {:?}", ty);
592                         None
593                     }
594                 }
595             }
596             ast::ExprKind::MethodCall(ref seg, ..) => {
597                 let expr_hir_id = self.tcx.hir.definitions().node_to_hir_id(expr.id);
598                 let method_id = match self.tables.type_dependent_defs().get(expr_hir_id) {
599                     Some(id) => id.def_id(),
600                     None => {
601                         debug!("Could not resolve method id for {:?}", expr);
602                         return None;
603                     }
604                 };
605                 let (def_id, decl_id) = match self.tcx.associated_item(method_id).container {
606                     ty::ImplContainer(_) => (Some(method_id), None),
607                     ty::TraitContainer(_) => (None, Some(method_id)),
608                 };
609                 let sub_span = seg.ident.span;
610                 filter!(self.span_utils, Some(sub_span), expr.span, None);
611                 let span = self.span_from_span(sub_span);
612                 Some(Data::RefData(Ref {
613                     kind: RefKind::Function,
614                     span,
615                     ref_id: def_id
616                         .or(decl_id)
617                         .map(|id| id_from_def_id(id))
618                         .unwrap_or(null_id()),
619                 }))
620             }
621             ast::ExprKind::Path(_, ref path) => {
622                 self.get_path_data(expr.id, path).map(|d| Data::RefData(d))
623             }
624             _ => {
625                 // FIXME
626                 bug!();
627             }
628         }
629     }
630
631     pub fn get_path_def(&self, id: NodeId) -> HirDef {
632         match self.tcx.hir.get(id) {
633             Node::NodeTraitRef(tr) => tr.path.def,
634
635             Node::NodeItem(&hir::Item {
636                 node: hir::ItemUse(ref path, _),
637                 ..
638             }) |
639             Node::NodeVisibility(&hir::Visibility::Restricted { ref path, .. }) => path.def,
640
641             Node::NodeExpr(&hir::Expr {
642                 node: hir::ExprStruct(ref qpath, ..),
643                 ..
644             }) |
645             Node::NodeExpr(&hir::Expr {
646                 node: hir::ExprPath(ref qpath),
647                 ..
648             }) |
649             Node::NodePat(&hir::Pat {
650                 node: hir::PatKind::Path(ref qpath),
651                 ..
652             }) |
653             Node::NodePat(&hir::Pat {
654                 node: hir::PatKind::Struct(ref qpath, ..),
655                 ..
656             }) |
657             Node::NodePat(&hir::Pat {
658                 node: hir::PatKind::TupleStruct(ref qpath, ..),
659                 ..
660             }) => {
661                 let hir_id = self.tcx.hir.node_to_hir_id(id);
662                 self.tables.qpath_def(qpath, hir_id)
663             }
664
665             Node::NodeBinding(&hir::Pat {
666                 node: hir::PatKind::Binding(_, canonical_id, ..),
667                 ..
668             }) => HirDef::Local(canonical_id),
669
670             Node::NodeTy(ty) => if let hir::Ty {
671                 node: hir::TyPath(ref qpath),
672                 ..
673             } = *ty
674             {
675                 match *qpath {
676                     hir::QPath::Resolved(_, ref path) => path.def,
677                     hir::QPath::TypeRelative(..) => {
678                         let ty = hir_ty_to_ty(self.tcx, ty);
679                         if let ty::TyProjection(proj) = ty.sty {
680                             return HirDef::AssociatedTy(proj.item_def_id);
681                         }
682                         HirDef::Err
683                     }
684                 }
685             } else {
686                 HirDef::Err
687             },
688
689             _ => HirDef::Err,
690         }
691     }
692
693     pub fn get_path_data(&self, id: NodeId, path: &ast::Path) -> Option<Ref> {
694         // Returns true if the path is function type sugar, e.g., `Fn(A) -> B`.
695         fn fn_type(path: &ast::Path) -> bool {
696             if path.segments.len() != 1 {
697                 return false;
698             }
699             if let Some(ref params) = path.segments[0].parameters {
700                 if let ast::PathParameters::Parenthesized(_) = **params {
701                     return true;
702                 }
703             }
704             false
705         }
706
707         if path.segments.is_empty() {
708             return None;
709         }
710
711         let def = self.get_path_def(id);
712         let last_seg = &path.segments[path.segments.len() - 1];
713         let sub_span = last_seg.ident.span;
714         filter!(self.span_utils, Some(sub_span), path.span, None);
715         match def {
716             HirDef::Upvar(id, ..) | HirDef::Local(id) => {
717                 let span = self.span_from_span(sub_span);
718                 Some(Ref {
719                     kind: RefKind::Variable,
720                     span,
721                     ref_id: id_from_node_id(id, self),
722                 })
723             }
724             HirDef::Static(..) |
725             HirDef::Const(..) |
726             HirDef::AssociatedConst(..) |
727             HirDef::VariantCtor(..) => {
728                 let span = self.span_from_span(sub_span);
729                 Some(Ref {
730                     kind: RefKind::Variable,
731                     span,
732                     ref_id: id_from_def_id(def.def_id()),
733                 })
734             }
735             HirDef::Trait(def_id) if fn_type(path) => {
736                 // Function type bounds are desugared in the parser, so we have to
737                 // special case them here.
738                 let fn_span = self.span_utils.span_for_first_ident(path.span);
739                 fn_span.map(|span| {
740                     Ref {
741                         kind: RefKind::Type,
742                         span: self.span_from_span(span),
743                         ref_id: id_from_def_id(def_id),
744                     }
745                 })
746             }
747             HirDef::Struct(def_id) |
748             HirDef::Variant(def_id, ..) |
749             HirDef::Union(def_id) |
750             HirDef::Enum(def_id) |
751             HirDef::TyAlias(def_id) |
752             HirDef::TyForeign(def_id) |
753             HirDef::TraitAlias(def_id) |
754             HirDef::AssociatedTy(def_id) |
755             HirDef::Trait(def_id) |
756             HirDef::TyParam(def_id) => {
757                 let span = self.span_from_span(sub_span);
758                 Some(Ref {
759                     kind: RefKind::Type,
760                     span,
761                     ref_id: id_from_def_id(def_id),
762                 })
763             }
764             HirDef::StructCtor(def_id, _) => {
765                 // This is a reference to a tuple struct where the def_id points
766                 // to an invisible constructor function. That is not a very useful
767                 // def, so adjust to point to the tuple struct itself.
768                 let span = self.span_from_span(sub_span);
769                 let parent_def_id = self.tcx.parent_def_id(def_id).unwrap();
770                 Some(Ref {
771                     kind: RefKind::Type,
772                     span,
773                     ref_id: id_from_def_id(parent_def_id),
774                 })
775             }
776             HirDef::Method(decl_id) => {
777                 let def_id = if decl_id.is_local() {
778                     let ti = self.tcx.associated_item(decl_id);
779                     self.tcx
780                         .associated_items(ti.container.id())
781                         .find(|item| item.name == ti.name && item.defaultness.has_value())
782                         .map(|item| item.def_id)
783                 } else {
784                     None
785                 };
786                 let span = self.span_from_span(sub_span);
787                 Some(Ref {
788                     kind: RefKind::Function,
789                     span,
790                     ref_id: id_from_def_id(def_id.unwrap_or(decl_id)),
791                 })
792             }
793             HirDef::Fn(def_id) => {
794                 let span = self.span_from_span(sub_span);
795                 Some(Ref {
796                     kind: RefKind::Function,
797                     span,
798                     ref_id: id_from_def_id(def_id),
799                 })
800             }
801             HirDef::Mod(def_id) => {
802                 let span = self.span_from_span(sub_span);
803                 Some(Ref {
804                     kind: RefKind::Mod,
805                     span,
806                     ref_id: id_from_def_id(def_id),
807                 })
808             }
809             HirDef::PrimTy(..) |
810             HirDef::SelfTy(..) |
811             HirDef::Label(..) |
812             HirDef::Macro(..) |
813             HirDef::GlobalAsm(..) |
814             HirDef::Err => None,
815         }
816     }
817
818     pub fn get_field_ref_data(
819         &self,
820         field_ref: &ast::Field,
821         variant: &ty::VariantDef,
822     ) -> Option<Ref> {
823         let index = self.tcx.find_field_index(field_ref.ident, variant).unwrap();
824         // We don't really need a sub-span here, but no harm done
825         let sub_span = self.span_utils.span_for_last_ident(field_ref.ident.span);
826         filter!(self.span_utils, sub_span, field_ref.ident.span, None);
827         let span = self.span_from_span(sub_span.unwrap());
828         Some(Ref {
829             kind: RefKind::Variable,
830             span,
831             ref_id: id_from_def_id(variant.fields[index].did),
832         })
833     }
834
835     /// Attempt to return MacroRef for any AST node.
836     ///
837     /// For a given piece of AST defined by the supplied Span and NodeId,
838     /// returns None if the node is not macro-generated or the span is malformed,
839     /// else uses the expansion callsite and callee to return some MacroRef.
840     pub fn get_macro_use_data(&self, span: Span) -> Option<MacroRef> {
841         if !generated_code(span) {
842             return None;
843         }
844         // Note we take care to use the source callsite/callee, to handle
845         // nested expansions and ensure we only generate data for source-visible
846         // macro uses.
847         let callsite = span.source_callsite();
848         let callsite_span = self.span_from_span(callsite);
849         let callee = span.source_callee()?;
850         let callee_span = callee.span?;
851
852         // Ignore attribute macros, their spans are usually mangled
853         if let MacroAttribute(_) = callee.format {
854             return None;
855         }
856
857         // If the callee is an imported macro from an external crate, need to get
858         // the source span and name from the session, as their spans are localized
859         // when read in, and no longer correspond to the source.
860         if let Some(mac) = self.tcx
861             .sess
862             .imported_macro_spans
863             .borrow()
864             .get(&callee_span)
865         {
866             let &(ref mac_name, mac_span) = mac;
867             let mac_span = self.span_from_span(mac_span);
868             return Some(MacroRef {
869                 span: callsite_span,
870                 qualname: mac_name.clone(), // FIXME: generate the real qualname
871                 callee_span: mac_span,
872             });
873         }
874
875         let callee_span = self.span_from_span(callee_span);
876         Some(MacroRef {
877             span: callsite_span,
878             qualname: callee.name().to_string(), // FIXME: generate the real qualname
879             callee_span,
880         })
881     }
882
883     fn lookup_ref_id(&self, ref_id: NodeId) -> Option<DefId> {
884         match self.get_path_def(ref_id) {
885             HirDef::PrimTy(_) | HirDef::SelfTy(..) | HirDef::Err => None,
886             def => Some(def.def_id()),
887         }
888     }
889
890     fn docs_for_attrs(&self, attrs: &[Attribute]) -> String {
891         let mut result = String::new();
892
893         for attr in attrs {
894             if attr.check_name("doc") {
895                 if let Some(val) = attr.value_str() {
896                     if attr.is_sugared_doc {
897                         result.push_str(&strip_doc_comment_decoration(&val.as_str()));
898                     } else {
899                         result.push_str(&val.as_str());
900                     }
901                     result.push('\n');
902                 } else if let Some(meta_list) = attr.meta_item_list() {
903                     meta_list.into_iter()
904                              .filter(|it| it.check_name("include"))
905                              .filter_map(|it| it.meta_item_list().map(|l| l.to_owned()))
906                              .flat_map(|it| it)
907                              .filter(|meta| meta.check_name("contents"))
908                              .filter_map(|meta| meta.value_str())
909                              .for_each(|val| {
910                                  result.push_str(&val.as_str());
911                                  result.push('\n');
912                              });
913                 }
914             }
915         }
916
917         if !self.config.full_docs {
918             if let Some(index) = result.find("\n\n") {
919                 result.truncate(index);
920             }
921         }
922
923         result
924     }
925
926     fn next_impl_id(&self) -> u32 {
927         let next = self.impl_counter.get();
928         self.impl_counter.set(next + 1);
929         next
930     }
931 }
932
933 fn make_signature(decl: &ast::FnDecl, generics: &ast::Generics) -> String {
934     let mut sig = "fn ".to_owned();
935     if !generics.params.is_empty() {
936         sig.push('<');
937         sig.push_str(&generics
938             .params
939             .iter()
940             .map(|param| match *param {
941                 ast::GenericParam::Lifetime(ref l) => l.lifetime.ident.name.to_string(),
942                 ast::GenericParam::Type(ref t) => t.ident.to_string(),
943             })
944             .collect::<Vec<_>>()
945             .join(", "));
946         sig.push_str("> ");
947     }
948     sig.push('(');
949     sig.push_str(&decl.inputs
950         .iter()
951         .map(arg_to_string)
952         .collect::<Vec<_>>()
953         .join(", "));
954     sig.push(')');
955     match decl.output {
956         ast::FunctionRetTy::Default(_) => sig.push_str(" -> ()"),
957         ast::FunctionRetTy::Ty(ref t) => sig.push_str(&format!(" -> {}", ty_to_string(t))),
958     }
959
960     sig
961 }
962
963 // An AST visitor for collecting paths (e.g., the names of structs) and formal
964 // variables (idents) from patterns.
965 struct PathCollector<'l> {
966     collected_paths: Vec<(NodeId, &'l ast::Path)>,
967     collected_idents: Vec<(NodeId, ast::Ident, ast::Mutability)>,
968 }
969
970 impl<'l> PathCollector<'l> {
971     fn new() -> PathCollector<'l> {
972         PathCollector {
973             collected_paths: vec![],
974             collected_idents: vec![],
975         }
976     }
977 }
978
979 impl<'l, 'a: 'l> Visitor<'a> for PathCollector<'l> {
980     fn visit_pat(&mut self, p: &'a ast::Pat) {
981         match p.node {
982             PatKind::Struct(ref path, ..) => {
983                 self.collected_paths.push((p.id, path));
984             }
985             PatKind::TupleStruct(ref path, ..) | PatKind::Path(_, ref path) => {
986                 self.collected_paths.push((p.id, path));
987             }
988             PatKind::Ident(bm, ident, _) => {
989                 debug!(
990                     "PathCollector, visit ident in pat {}: {:?} {:?}",
991                     ident,
992                     p.span,
993                     ident.span
994                 );
995                 let immut = match bm {
996                     // Even if the ref is mut, you can't change the ref, only
997                     // the data pointed at, so showing the initialising expression
998                     // is still worthwhile.
999                     ast::BindingMode::ByRef(_) => ast::Mutability::Immutable,
1000                     ast::BindingMode::ByValue(mt) => mt,
1001                 };
1002                 self.collected_idents
1003                     .push((p.id, ident, immut));
1004             }
1005             _ => {}
1006         }
1007         visit::walk_pat(self, p);
1008     }
1009 }
1010
1011 /// Defines what to do with the results of saving the analysis.
1012 pub trait SaveHandler {
1013     fn save<'l, 'tcx>(
1014         &mut self,
1015         save_ctxt: SaveContext<'l, 'tcx>,
1016         krate: &ast::Crate,
1017         cratename: &str,
1018     );
1019 }
1020
1021 /// Dump the save-analysis results to a file.
1022 pub struct DumpHandler<'a> {
1023     odir: Option<&'a Path>,
1024     cratename: String,
1025 }
1026
1027 impl<'a> DumpHandler<'a> {
1028     pub fn new(odir: Option<&'a Path>, cratename: &str) -> DumpHandler<'a> {
1029         DumpHandler {
1030             odir,
1031             cratename: cratename.to_owned(),
1032         }
1033     }
1034
1035     fn output_file(&self, ctx: &SaveContext) -> File {
1036         let sess = &ctx.tcx.sess;
1037         let file_name = match ctx.config.output_file {
1038             Some(ref s) => PathBuf::from(s),
1039             None => {
1040                 let mut root_path = match self.odir {
1041                     Some(val) => val.join("save-analysis"),
1042                     None => PathBuf::from("save-analysis-temp"),
1043                 };
1044
1045                 if let Err(e) = std::fs::create_dir_all(&root_path) {
1046                     error!("Could not create directory {}: {}", root_path.display(), e);
1047                 }
1048
1049                 let executable = sess.crate_types
1050                     .borrow()
1051                     .iter()
1052                     .any(|ct| *ct == CrateTypeExecutable);
1053                 let mut out_name = if executable {
1054                     "".to_owned()
1055                 } else {
1056                     "lib".to_owned()
1057                 };
1058                 out_name.push_str(&self.cratename);
1059                 out_name.push_str(&sess.opts.cg.extra_filename);
1060                 out_name.push_str(".json");
1061                 root_path.push(&out_name);
1062
1063                 root_path
1064             }
1065         };
1066
1067         info!("Writing output to {}", file_name.display());
1068
1069         let output_file = File::create(&file_name).unwrap_or_else(
1070             |e| sess.fatal(&format!("Could not open {}: {}", file_name.display(), e)),
1071         );
1072
1073         output_file
1074     }
1075 }
1076
1077 impl<'a> SaveHandler for DumpHandler<'a> {
1078     fn save<'l, 'tcx>(
1079         &mut self,
1080         save_ctxt: SaveContext<'l, 'tcx>,
1081         krate: &ast::Crate,
1082         cratename: &str,
1083     ) {
1084         let output = &mut self.output_file(&save_ctxt);
1085         let mut dumper = JsonDumper::new(output, save_ctxt.config.clone());
1086         let mut visitor = DumpVisitor::new(save_ctxt, &mut dumper);
1087
1088         visitor.dump_crate_info(cratename, krate);
1089         visit::walk_crate(&mut visitor, krate);
1090     }
1091 }
1092
1093 /// Call a callback with the results of save-analysis.
1094 pub struct CallbackHandler<'b> {
1095     pub callback: &'b mut FnMut(&rls_data::Analysis),
1096 }
1097
1098 impl<'b> SaveHandler for CallbackHandler<'b> {
1099     fn save<'l, 'tcx>(
1100         &mut self,
1101         save_ctxt: SaveContext<'l, 'tcx>,
1102         krate: &ast::Crate,
1103         cratename: &str,
1104     ) {
1105         // We're using the JsonDumper here because it has the format of the
1106         // save-analysis results that we will pass to the callback. IOW, we are
1107         // using the JsonDumper to collect the save-analysis results, but not
1108         // actually to dump them to a file. This is all a bit convoluted and
1109         // there is certainly a simpler design here trying to get out (FIXME).
1110         let mut dumper = JsonDumper::with_callback(self.callback, save_ctxt.config.clone());
1111         let mut visitor = DumpVisitor::new(save_ctxt, &mut dumper);
1112
1113         visitor.dump_crate_info(cratename, krate);
1114         visit::walk_crate(&mut visitor, krate);
1115     }
1116 }
1117
1118 pub fn process_crate<'l, 'tcx, H: SaveHandler>(
1119     tcx: TyCtxt<'l, 'tcx, 'tcx>,
1120     krate: &ast::Crate,
1121     analysis: &'l ty::CrateAnalysis,
1122     cratename: &str,
1123     config: Option<Config>,
1124     mut handler: H,
1125 ) {
1126     tcx.dep_graph.with_ignore(|| {
1127         assert!(analysis.glob_map.is_some());
1128
1129         info!("Dumping crate {}", cratename);
1130
1131         let save_ctxt = SaveContext {
1132             tcx,
1133             tables: &ty::TypeckTables::empty(None),
1134             analysis,
1135             span_utils: SpanUtils::new(&tcx.sess),
1136             config: find_config(config),
1137             impl_counter: Cell::new(0),
1138         };
1139
1140         handler.save(save_ctxt, krate, cratename)
1141     })
1142 }
1143
1144 fn find_config(supplied: Option<Config>) -> Config {
1145     if let Some(config) = supplied {
1146         return config;
1147     }
1148     match env::var_os("RUST_SAVE_ANALYSIS_CONFIG") {
1149         Some(config_string) => rustc_serialize::json::decode(config_string.to_str().unwrap())
1150             .expect("Could not deserialize save-analysis config"),
1151         None => Config::default(),
1152     }
1153 }
1154
1155 // Utility functions for the module.
1156
1157 // Helper function to escape quotes in a string
1158 fn escape(s: String) -> String {
1159     s.replace("\"", "\"\"")
1160 }
1161
1162 // Helper function to determine if a span came from a
1163 // macro expansion or syntax extension.
1164 fn generated_code(span: Span) -> bool {
1165     span.ctxt() != NO_EXPANSION || span == DUMMY_SP
1166 }
1167
1168 // DefId::index is a newtype and so the JSON serialisation is ugly. Therefore
1169 // we use our own Id which is the same, but without the newtype.
1170 fn id_from_def_id(id: DefId) -> rls_data::Id {
1171     rls_data::Id {
1172         krate: id.krate.as_u32(),
1173         index: id.index.as_raw_u32(),
1174     }
1175 }
1176
1177 fn id_from_node_id(id: NodeId, scx: &SaveContext) -> rls_data::Id {
1178     let def_id = scx.tcx.hir.opt_local_def_id(id);
1179     def_id.map(|id| id_from_def_id(id)).unwrap_or_else(|| {
1180         // Create a *fake* `DefId` out of a `NodeId` by subtracting the `NodeId`
1181         // out of the maximum u32 value. This will work unless you have *billions*
1182         // of definitions in a single crate (very unlikely to actually happen).
1183         rls_data::Id {
1184             krate: LOCAL_CRATE.as_u32(),
1185             index: !id.as_u32(),
1186         }
1187     })
1188 }
1189
1190 fn null_id() -> rls_data::Id {
1191     rls_data::Id {
1192         krate: u32::max_value(),
1193         index: u32::max_value(),
1194     }
1195 }
1196
1197 fn lower_attributes(attrs: Vec<Attribute>, scx: &SaveContext) -> Vec<rls_data::Attribute> {
1198     attrs.into_iter()
1199     // Only retain real attributes. Doc comments are lowered separately.
1200     .filter(|attr| attr.path != "doc")
1201     .map(|mut attr| {
1202         // Remove the surrounding '#[..]' or '#![..]' of the pretty printed
1203         // attribute. First normalize all inner attribute (#![..]) to outer
1204         // ones (#[..]), then remove the two leading and the one trailing character.
1205         attr.style = ast::AttrStyle::Outer;
1206         let value = pprust::attribute_to_string(&attr);
1207         // This str slicing works correctly, because the leading and trailing characters
1208         // are in the ASCII range and thus exactly one byte each.
1209         let value = value[2..value.len()-1].to_string();
1210
1211         rls_data::Attribute {
1212             value,
1213             span: scx.span_from_span(attr.span),
1214         }
1215     }).collect()
1216 }