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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 pub use self::Node::*;
12 pub use self::PathElem::*;
13 use self::MapEntry::*;
14 use self::collector::NodeCollector;
15 pub use self::definitions::{Definitions, DefKey, DefPath, DefPathData, DisambiguatedDefPathData};
16
17 use dep_graph::{DepGraph, DepNode};
18
19 use middle::cstore::InlinedItem;
20 use middle::cstore::InlinedItem as II;
21 use middle::def_id::DefId;
22
23 use syntax::abi::Abi;
24 use syntax::ast::{self, Name, NodeId, DUMMY_NODE_ID};
25 use syntax::codemap::{Span, Spanned};
26 use syntax::parse::token;
27
28 use rustc_front::hir::*;
29 use rustc_front::fold::Folder;
30 use rustc_front::intravisit;
31 use rustc_front::print::pprust;
32
33 use arena::TypedArena;
34 use std::cell::RefCell;
35 use std::fmt;
36 use std::io;
37 use std::iter;
38 use std::mem;
39 use std::slice;
40
41 pub mod blocks;
42 mod collector;
43 pub mod definitions;
44
45 #[derive(Clone, Copy, PartialEq, Debug)]
46 pub enum PathElem {
47 PathMod(Name),
48 PathName(Name)
49 }
50
51 impl PathElem {
52 pub fn name(&self) -> Name {
53 match *self {
54 PathMod(name) | PathName(name) => name
55 }
56 }
57 }
58
59 impl fmt::Display for PathElem {
60 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
61 write!(f, "{}", self.name())
62 }
63 }
64
65 #[derive(Clone)]
66 pub struct LinkedPathNode<'a> {
67 node: PathElem,
68 next: LinkedPath<'a>,
69 }
70
71 #[derive(Copy, Clone)]
72 pub struct LinkedPath<'a>(Option<&'a LinkedPathNode<'a>>);
73
74 impl<'a> LinkedPath<'a> {
75 pub fn empty() -> LinkedPath<'a> {
76 LinkedPath(None)
77 }
78
79 pub fn from(node: &'a LinkedPathNode) -> LinkedPath<'a> {
80 LinkedPath(Some(node))
81 }
82 }
83
84 impl<'a> Iterator for LinkedPath<'a> {
85 type Item = PathElem;
86
87 fn next(&mut self) -> Option<PathElem> {
88 match self.0 {
89 Some(node) => {
90 *self = node.next;
91 Some(node.node)
92 }
93 None => None
94 }
95 }
96 }
97
98 /// The type of the iterator used by with_path.
99 pub type PathElems<'a, 'b> = iter::Chain<iter::Cloned<slice::Iter<'a, PathElem>>, LinkedPath<'b>>;
100
101 pub fn path_to_string<PI: Iterator<Item=PathElem>>(path: PI) -> String {
102 let itr = token::get_ident_interner();
103
104 path.fold(String::new(), |mut s, e| {
105 let e = itr.get(e.name());
106 if !s.is_empty() {
107 s.push_str("::");
108 }
109 s.push_str(&e[..]);
110 s
111 })
112 }
113
114 #[derive(Copy, Clone, Debug)]
115 pub enum Node<'ast> {
116 NodeItem(&'ast Item),
117 NodeForeignItem(&'ast ForeignItem),
118 NodeTraitItem(&'ast TraitItem),
119 NodeImplItem(&'ast ImplItem),
120 NodeVariant(&'ast Variant),
121 NodeExpr(&'ast Expr),
122 NodeStmt(&'ast Stmt),
123 NodeLocal(&'ast Pat),
124 NodePat(&'ast Pat),
125 NodeBlock(&'ast Block),
126
127 /// NodeStructCtor represents a tuple struct.
128 NodeStructCtor(&'ast VariantData),
129
130 NodeLifetime(&'ast Lifetime),
131 NodeTyParam(&'ast TyParam)
132 }
133
134 /// Represents an entry and its parent NodeID.
135 /// The odd layout is to bring down the total size.
136 #[derive(Copy, Debug)]
137 pub enum MapEntry<'ast> {
138 /// Placeholder for holes in the map.
139 NotPresent,
140
141 /// All the node types, with a parent ID.
142 EntryItem(NodeId, &'ast Item),
143 EntryForeignItem(NodeId, &'ast ForeignItem),
144 EntryTraitItem(NodeId, &'ast TraitItem),
145 EntryImplItem(NodeId, &'ast ImplItem),
146 EntryVariant(NodeId, &'ast Variant),
147 EntryExpr(NodeId, &'ast Expr),
148 EntryStmt(NodeId, &'ast Stmt),
149 EntryLocal(NodeId, &'ast Pat),
150 EntryPat(NodeId, &'ast Pat),
151 EntryBlock(NodeId, &'ast Block),
152 EntryStructCtor(NodeId, &'ast VariantData),
153 EntryLifetime(NodeId, &'ast Lifetime),
154 EntryTyParam(NodeId, &'ast TyParam),
155
156 /// Roots for node trees.
157 RootCrate,
158 RootInlinedParent(&'ast InlinedParent)
159 }
160
161 impl<'ast> Clone for MapEntry<'ast> {
162 fn clone(&self) -> MapEntry<'ast> {
163 *self
164 }
165 }
166
167 #[derive(Debug)]
168 pub struct InlinedParent {
169 path: Vec<PathElem>,
170 ii: InlinedItem
171 }
172
173 impl<'ast> MapEntry<'ast> {
174 fn from_node(p: NodeId, node: Node<'ast>) -> MapEntry<'ast> {
175 match node {
176 NodeItem(n) => EntryItem(p, n),
177 NodeForeignItem(n) => EntryForeignItem(p, n),
178 NodeTraitItem(n) => EntryTraitItem(p, n),
179 NodeImplItem(n) => EntryImplItem(p, n),
180 NodeVariant(n) => EntryVariant(p, n),
181 NodeExpr(n) => EntryExpr(p, n),
182 NodeStmt(n) => EntryStmt(p, n),
183 NodeLocal(n) => EntryLocal(p, n),
184 NodePat(n) => EntryPat(p, n),
185 NodeBlock(n) => EntryBlock(p, n),
186 NodeStructCtor(n) => EntryStructCtor(p, n),
187 NodeLifetime(n) => EntryLifetime(p, n),
188 NodeTyParam(n) => EntryTyParam(p, n),
189 }
190 }
191
192 fn parent_node(self) -> Option<NodeId> {
193 Some(match self {
194 EntryItem(id, _) => id,
195 EntryForeignItem(id, _) => id,
196 EntryTraitItem(id, _) => id,
197 EntryImplItem(id, _) => id,
198 EntryVariant(id, _) => id,
199 EntryExpr(id, _) => id,
200 EntryStmt(id, _) => id,
201 EntryLocal(id, _) => id,
202 EntryPat(id, _) => id,
203 EntryBlock(id, _) => id,
204 EntryStructCtor(id, _) => id,
205 EntryLifetime(id, _) => id,
206 EntryTyParam(id, _) => id,
207 _ => return None
208 })
209 }
210
211 fn to_node(self) -> Option<Node<'ast>> {
212 Some(match self {
213 EntryItem(_, n) => NodeItem(n),
214 EntryForeignItem(_, n) => NodeForeignItem(n),
215 EntryTraitItem(_, n) => NodeTraitItem(n),
216 EntryImplItem(_, n) => NodeImplItem(n),
217 EntryVariant(_, n) => NodeVariant(n),
218 EntryExpr(_, n) => NodeExpr(n),
219 EntryStmt(_, n) => NodeStmt(n),
220 EntryLocal(_, n) => NodeLocal(n),
221 EntryPat(_, n) => NodePat(n),
222 EntryBlock(_, n) => NodeBlock(n),
223 EntryStructCtor(_, n) => NodeStructCtor(n),
224 EntryLifetime(_, n) => NodeLifetime(n),
225 EntryTyParam(_, n) => NodeTyParam(n),
226 _ => return None
227 })
228 }
229 }
230
231 /// Stores a crate and any number of inlined items from other crates.
232 pub struct Forest {
233 krate: Crate,
234 pub dep_graph: DepGraph,
235 inlined_items: TypedArena<InlinedParent>
236 }
237
238 impl Forest {
239 pub fn new(krate: Crate, dep_graph: DepGraph) -> Forest {
240 Forest {
241 krate: krate,
242 dep_graph: dep_graph,
243 inlined_items: TypedArena::new()
244 }
245 }
246
247 pub fn krate<'ast>(&'ast self) -> &'ast Crate {
248 self.dep_graph.read(DepNode::Krate);
249 &self.krate
250 }
251 }
252
253 /// Represents a mapping from Node IDs to AST elements and their parent
254 /// Node IDs
255 #[derive(Clone)]
256 pub struct Map<'ast> {
257 /// The backing storage for all the AST nodes.
258 pub forest: &'ast Forest,
259
260 /// Same as the dep_graph in forest, just available with one fewer
261 /// deref. This is a gratuitious micro-optimization.
262 pub dep_graph: DepGraph,
263
264 /// NodeIds are sequential integers from 0, so we can be
265 /// super-compact by storing them in a vector. Not everything with
266 /// a NodeId is in the map, but empirically the occupancy is about
267 /// 75-80%, so there's not too much overhead (certainly less than
268 /// a hashmap, since they (at the time of writing) have a maximum
269 /// of 75% occupancy).
270 ///
271 /// Also, indexing is pretty quick when you've got a vector and
272 /// plain old integers.
273 map: RefCell<Vec<MapEntry<'ast>>>,
274
275 definitions: RefCell<Definitions>,
276 }
277
278 impl<'ast> Map<'ast> {
279 /// Registers a read in the dependency graph of the AST node with
280 /// the given `id`. This needs to be called each time a public
281 /// function returns the HIR for a node -- in other words, when it
282 /// "reveals" the content of a node to the caller (who might not
283 /// otherwise have had access to those contents, and hence needs a
284 /// read recorded). If the function just returns a DefId or
285 /// NodeId, no actual content was returned, so no read is needed.
286 fn read(&self, id: NodeId) {
287 self.dep_graph.read(self.dep_node(id));
288 }
289
290 fn dep_node(&self, id0: NodeId) -> DepNode {
291 let map = self.map.borrow();
292 let mut id = id0;
293 loop {
294 match map[id as usize] {
295 EntryItem(_, item) => {
296 let def_id = self.local_def_id(item.id);
297 // NB ^~~~~~~
298 //
299 // You would expect that `item.id == id`, but this
300 // is not always the case. In particular, for a
301 // ViewPath item like `use self::{mem, foo}`, we
302 // map the ids for `mem` and `foo` to the
303 // enclosing view path item. This seems mega super
304 // ultra wrong, but then who am I to judge?
305 // -nmatsakis
306 return DepNode::Hir(def_id);
307 }
308
309 EntryForeignItem(p, _) |
310 EntryTraitItem(p, _) |
311 EntryImplItem(p, _) |
312 EntryVariant(p, _) |
313 EntryExpr(p, _) |
314 EntryStmt(p, _) |
315 EntryLocal(p, _) |
316 EntryPat(p, _) |
317 EntryBlock(p, _) |
318 EntryStructCtor(p, _) |
319 EntryLifetime(p, _) |
320 EntryTyParam(p, _) =>
321 id = p,
322
323 RootCrate |
324 RootInlinedParent(_) => // FIXME(#2369) clarify story about cross-crate dep tracking
325 return DepNode::Krate,
326
327 NotPresent =>
328 // Some nodes, notably struct fields, are not
329 // present in the map for whatever reason, but
330 // they *do* have def-ids. So if we encounter an
331 // empty hole, check for that case.
332 return self.opt_local_def_id(id)
333 .map(|def_id| DepNode::Hir(def_id))
334 .unwrap_or_else(|| {
335 panic!("Walking parents from `{}` \
336 led to `NotPresent` at `{}`",
337 id0, id)
338 }),
339 }
340 }
341 }
342
343 pub fn num_local_def_ids(&self) -> usize {
344 self.definitions.borrow().len()
345 }
346
347 pub fn def_key(&self, def_id: DefId) -> DefKey {
348 assert!(def_id.is_local());
349 self.definitions.borrow().def_key(def_id.index)
350 }
351
352 pub fn def_path_from_id(&self, id: NodeId) -> DefPath {
353 self.def_path(self.local_def_id(id))
354 }
355
356 pub fn def_path(&self, def_id: DefId) -> DefPath {
357 assert!(def_id.is_local());
358 self.definitions.borrow().def_path(def_id.index)
359 }
360
361 pub fn local_def_id(&self, node: NodeId) -> DefId {
362 self.opt_local_def_id(node).unwrap_or_else(|| {
363 panic!("local_def_id: no entry for `{}`, which has a map of `{:?}`",
364 node, self.find_entry(node))
365 })
366 }
367
368 pub fn opt_local_def_id(&self, node: NodeId) -> Option<DefId> {
369 self.definitions.borrow().opt_local_def_id(node)
370 }
371
372 pub fn as_local_node_id(&self, def_id: DefId) -> Option<NodeId> {
373 self.definitions.borrow().as_local_node_id(def_id)
374 }
375
376 fn entry_count(&self) -> usize {
377 self.map.borrow().len()
378 }
379
380 fn find_entry(&self, id: NodeId) -> Option<MapEntry<'ast>> {
381 self.map.borrow().get(id as usize).cloned()
382 }
383
384 pub fn krate(&self) -> &'ast Crate {
385 self.forest.krate()
386 }
387
388 /// Retrieve the Node corresponding to `id`, panicking if it cannot
389 /// be found.
390 pub fn get(&self, id: NodeId) -> Node<'ast> {
391 match self.find(id) {
392 Some(node) => node, // read recorded by `find`
393 None => panic!("couldn't find node id {} in the AST map", id)
394 }
395 }
396
397 pub fn get_if_local(&self, id: DefId) -> Option<Node<'ast>> {
398 self.as_local_node_id(id).map(|id| self.get(id)) // read recorded by `get`
399 }
400
401 /// Retrieve the Node corresponding to `id`, returning None if
402 /// cannot be found.
403 pub fn find(&self, id: NodeId) -> Option<Node<'ast>> {
404 let result = self.find_entry(id).and_then(|x| x.to_node());
405 if result.is_some() {
406 self.read(id);
407 }
408 result
409 }
410
411 /// Similar to get_parent, returns the parent node id or id if there is no
412 /// parent.
413 /// This function returns the immediate parent in the AST, whereas get_parent
414 /// returns the enclosing item. Note that this might not be the actual parent
415 /// node in the AST - some kinds of nodes are not in the map and these will
416 /// never appear as the parent_node. So you can always walk the parent_nodes
417 /// from a node to the root of the ast (unless you get the same id back here
418 /// that can happen if the id is not in the map itself or is just weird).
419 pub fn get_parent_node(&self, id: NodeId) -> NodeId {
420 self.find_entry(id).and_then(|x| x.parent_node()).unwrap_or(id)
421 }
422
423 /// Check if the node is an argument. An argument is a local variable whose
424 /// immediate parent is an item or a closure.
425 pub fn is_argument(&self, id: NodeId) -> bool {
426 match self.find(id) {
427 Some(NodeLocal(_)) => (),
428 _ => return false,
429 }
430 match self.find(self.get_parent_node(id)) {
431 Some(NodeItem(_)) |
432 Some(NodeTraitItem(_)) |
433 Some(NodeImplItem(_)) => true,
434 Some(NodeExpr(e)) => {
435 match e.node {
436 ExprClosure(..) => true,
437 _ => false,
438 }
439 }
440 _ => false,
441 }
442 }
443
444 /// If there is some error when walking the parents (e.g., a node does not
445 /// have a parent in the map or a node can't be found), then we return the
446 /// last good node id we found. Note that reaching the crate root (id == 0),
447 /// is not an error, since items in the crate module have the crate root as
448 /// parent.
449 fn walk_parent_nodes<F>(&self, start_id: NodeId, found: F) -> Result<NodeId, NodeId>
450 where F: Fn(&Node<'ast>) -> bool
451 {
452 let mut id = start_id;
453 loop {
454 let parent_node = self.get_parent_node(id);
455 if parent_node == 0 {
456 return Ok(0);
457 }
458 if parent_node == id {
459 return Err(id);
460 }
461
462 let node = self.find_entry(parent_node);
463 if node.is_none() {
464 return Err(id);
465 }
466 let node = node.unwrap().to_node();
467 match node {
468 Some(ref node) => {
469 if found(node) {
470 return Ok(parent_node);
471 }
472 }
473 None => {
474 return Err(parent_node);
475 }
476 }
477 id = parent_node;
478 }
479 }
480
481 /// Retrieve the NodeId for `id`'s parent item, or `id` itself if no
482 /// parent item is in this map. The "parent item" is the closest parent node
483 /// in the AST which is recorded by the map and is an item, either an item
484 /// in a module, trait, or impl.
485 pub fn get_parent(&self, id: NodeId) -> NodeId {
486 match self.walk_parent_nodes(id, |node| match *node {
487 NodeItem(_) |
488 NodeForeignItem(_) |
489 NodeTraitItem(_) |
490 NodeImplItem(_) => true,
491 _ => false,
492 }) {
493 Ok(id) => id,
494 Err(id) => id,
495 }
496 }
497
498 /// Returns the nearest enclosing scope. A scope is an item or block.
499 /// FIXME it is not clear to me that all items qualify as scopes - statics
500 /// and associated types probably shouldn't, for example. Behaviour in this
501 /// regard should be expected to be highly unstable.
502 pub fn get_enclosing_scope(&self, id: NodeId) -> Option<NodeId> {
503 match self.walk_parent_nodes(id, |node| match *node {
504 NodeItem(_) |
505 NodeForeignItem(_) |
506 NodeTraitItem(_) |
507 NodeImplItem(_) |
508 NodeBlock(_) => true,
509 _ => false,
510 }) {
511 Ok(id) => Some(id),
512 Err(_) => None,
513 }
514 }
515
516 pub fn get_parent_did(&self, id: NodeId) -> DefId {
517 let parent = self.get_parent(id);
518 match self.find_entry(parent) {
519 Some(RootInlinedParent(&InlinedParent {ii: II::TraitItem(did, _), ..})) => did,
520 Some(RootInlinedParent(&InlinedParent {ii: II::ImplItem(did, _), ..})) => did,
521 _ => self.local_def_id(parent)
522 }
523 }
524
525 pub fn get_foreign_abi(&self, id: NodeId) -> Abi {
526 let parent = self.get_parent(id);
527 let abi = match self.find_entry(parent) {
528 Some(EntryItem(_, i)) => {
529 match i.node {
530 ItemForeignMod(ref nm) => Some(nm.abi),
531 _ => None
532 }
533 }
534 /// Wrong but OK, because the only inlined foreign items are intrinsics.
535 Some(RootInlinedParent(_)) => Some(Abi::RustIntrinsic),
536 _ => None
537 };
538 match abi {
539 Some(abi) => {
540 self.read(id); // reveals some of the content of a node
541 abi
542 }
543 None => panic!("expected foreign mod or inlined parent, found {}",
544 self.node_to_string(parent))
545 }
546 }
547
548 pub fn get_foreign_vis(&self, id: NodeId) -> Visibility {
549 let vis = self.expect_foreign_item(id).vis; // read recorded by `expect_foreign_item`
550 match self.find(self.get_parent(id)) { // read recorded by `find`
551 Some(NodeItem(i)) => vis.inherit_from(i.vis),
552 _ => vis
553 }
554 }
555
556 pub fn expect_item(&self, id: NodeId) -> &'ast Item {
557 match self.find(id) { // read recorded by `find`
558 Some(NodeItem(item)) => item,
559 _ => panic!("expected item, found {}", self.node_to_string(id))
560 }
561 }
562
563 pub fn expect_trait_item(&self, id: NodeId) -> &'ast TraitItem {
564 match self.find(id) {
565 Some(NodeTraitItem(item)) => item,
566 _ => panic!("expected trait item, found {}", self.node_to_string(id))
567 }
568 }
569
570 pub fn expect_struct(&self, id: NodeId) -> &'ast VariantData {
571 match self.find(id) {
572 Some(NodeItem(i)) => {
573 match i.node {
574 ItemStruct(ref struct_def, _) => struct_def,
575 _ => panic!("struct ID bound to non-struct")
576 }
577 }
578 Some(NodeVariant(variant)) => {
579 if variant.node.data.is_struct() {
580 &variant.node.data
581 } else {
582 panic!("struct ID bound to enum variant that isn't struct-like")
583 }
584 }
585 _ => panic!(format!("expected struct, found {}", self.node_to_string(id))),
586 }
587 }
588
589 pub fn expect_variant(&self, id: NodeId) -> &'ast Variant {
590 match self.find(id) {
591 Some(NodeVariant(variant)) => variant,
592 _ => panic!(format!("expected variant, found {}", self.node_to_string(id))),
593 }
594 }
595
596 pub fn expect_foreign_item(&self, id: NodeId) -> &'ast ForeignItem {
597 match self.find(id) {
598 Some(NodeForeignItem(item)) => item,
599 _ => panic!("expected foreign item, found {}", self.node_to_string(id))
600 }
601 }
602
603 pub fn expect_expr(&self, id: NodeId) -> &'ast Expr {
604 match self.find(id) { // read recorded by find
605 Some(NodeExpr(expr)) => expr,
606 _ => panic!("expected expr, found {}", self.node_to_string(id))
607 }
608 }
609
610 /// returns the name associated with the given NodeId's AST
611 pub fn get_path_elem(&self, id: NodeId) -> PathElem {
612 let node = self.get(id);
613 match node {
614 NodeItem(item) => {
615 match item.node {
616 ItemMod(_) | ItemForeignMod(_) => {
617 PathMod(item.name)
618 }
619 _ => PathName(item.name)
620 }
621 }
622 NodeForeignItem(i) => PathName(i.name),
623 NodeImplItem(ii) => PathName(ii.name),
624 NodeTraitItem(ti) => PathName(ti.name),
625 NodeVariant(v) => PathName(v.node.name),
626 NodeLifetime(lt) => PathName(lt.name),
627 NodeTyParam(tp) => PathName(tp.name),
628 NodeLocal(&Pat { node: PatKind::Ident(_,l,_), .. }) => {
629 PathName(l.node.name)
630 },
631 _ => panic!("no path elem for {:?}", node)
632 }
633 }
634
635 pub fn with_path<T, F>(&self, id: NodeId, f: F) -> T where
636 F: FnOnce(PathElems) -> T,
637 {
638 self.with_path_next(id, LinkedPath::empty(), f)
639 }
640
641 pub fn path_to_string(&self, id: NodeId) -> String {
642 self.with_path(id, |path| path_to_string(path))
643 }
644
645 fn path_to_str_with_name(&self, id: NodeId, name: Name) -> String {
646 self.with_path(id, |path| {
647 path_to_string(path.chain(Some(PathName(name))))
648 })
649 }
650
651 fn with_path_next<T, F>(&self, id: NodeId, next: LinkedPath, f: F) -> T where
652 F: FnOnce(PathElems) -> T,
653 {
654 // This function reveals the name of the item and hence is a
655 // kind of read. This is inefficient, since it walks ancestors
656 // and we are walking them anyhow, but whatever.
657 self.read(id);
658
659 let parent = self.get_parent(id);
660 let parent = match self.find_entry(id) {
661 Some(EntryForeignItem(..)) => {
662 // Anonymous extern items go in the parent scope.
663 self.get_parent(parent)
664 }
665 // But tuple struct ctors don't have names, so use the path of its
666 // parent, the struct item. Similarly with closure expressions.
667 Some(EntryStructCtor(..)) | Some(EntryExpr(..)) => {
668 return self.with_path_next(parent, next, f);
669 }
670 _ => parent
671 };
672 if parent == id {
673 match self.find_entry(id) {
674 Some(RootInlinedParent(data)) => {
675 f(data.path.iter().cloned().chain(next))
676 }
677 _ => f([].iter().cloned().chain(next))
678 }
679 } else {
680 self.with_path_next(parent, LinkedPath::from(&LinkedPathNode {
681 node: self.get_path_elem(id),
682 next: next
683 }), f)
684 }
685 }
686
687 /// Given a node ID, get a list of attributes associated with the AST
688 /// corresponding to the Node ID
689 pub fn attrs(&self, id: NodeId) -> &'ast [ast::Attribute] {
690 self.read(id); // reveals attributes on the node
691 let attrs = match self.find(id) {
692 Some(NodeItem(i)) => Some(&i.attrs[..]),
693 Some(NodeForeignItem(fi)) => Some(&fi.attrs[..]),
694 Some(NodeTraitItem(ref ti)) => Some(&ti.attrs[..]),
695 Some(NodeImplItem(ref ii)) => Some(&ii.attrs[..]),
696 Some(NodeVariant(ref v)) => Some(&v.node.attrs[..]),
697 // unit/tuple structs take the attributes straight from
698 // the struct definition.
699 Some(NodeStructCtor(_)) => {
700 return self.attrs(self.get_parent(id));
701 }
702 _ => None
703 };
704 attrs.unwrap_or(&[])
705 }
706
707 /// Returns an iterator that yields the node id's with paths that
708 /// match `parts`. (Requires `parts` is non-empty.)
709 ///
710 /// For example, if given `parts` equal to `["bar", "quux"]`, then
711 /// the iterator will produce node id's for items with paths
712 /// such as `foo::bar::quux`, `bar::quux`, `other::bar::quux`, and
713 /// any other such items it can find in the map.
714 pub fn nodes_matching_suffix<'a>(&'a self, parts: &'a [String])
715 -> NodesMatchingSuffix<'a, 'ast> {
716 NodesMatchingSuffix {
717 map: self,
718 item_name: parts.last().unwrap(),
719 in_which: &parts[..parts.len() - 1],
720 idx: 0,
721 }
722 }
723
724 pub fn opt_span(&self, id: NodeId) -> Option<Span> {
725 let sp = match self.find(id) {
726 Some(NodeItem(item)) => item.span,
727 Some(NodeForeignItem(foreign_item)) => foreign_item.span,
728 Some(NodeTraitItem(trait_method)) => trait_method.span,
729 Some(NodeImplItem(ref impl_item)) => impl_item.span,
730 Some(NodeVariant(variant)) => variant.span,
731 Some(NodeExpr(expr)) => expr.span,
732 Some(NodeStmt(stmt)) => stmt.span,
733 Some(NodeLocal(pat)) => pat.span,
734 Some(NodePat(pat)) => pat.span,
735 Some(NodeBlock(block)) => block.span,
736 Some(NodeStructCtor(_)) => self.expect_item(self.get_parent(id)).span,
737 Some(NodeTyParam(ty_param)) => ty_param.span,
738 _ => return None,
739 };
740 Some(sp)
741 }
742
743 pub fn span(&self, id: NodeId) -> Span {
744 self.read(id); // reveals span from node
745 self.opt_span(id)
746 .unwrap_or_else(|| panic!("AstMap.span: could not find span for id {:?}", id))
747 }
748
749 pub fn span_if_local(&self, id: DefId) -> Option<Span> {
750 self.as_local_node_id(id).map(|id| self.span(id))
751 }
752
753 pub fn def_id_span(&self, def_id: DefId, fallback: Span) -> Span {
754 if let Some(node_id) = self.as_local_node_id(def_id) {
755 self.opt_span(node_id).unwrap_or(fallback)
756 } else {
757 fallback
758 }
759 }
760
761 pub fn node_to_string(&self, id: NodeId) -> String {
762 node_id_to_string(self, id, true)
763 }
764
765 pub fn node_to_user_string(&self, id: NodeId) -> String {
766 node_id_to_string(self, id, false)
767 }
768 }
769
770 pub struct NodesMatchingSuffix<'a, 'ast:'a> {
771 map: &'a Map<'ast>,
772 item_name: &'a String,
773 in_which: &'a [String],
774 idx: NodeId,
775 }
776
777 impl<'a, 'ast> NodesMatchingSuffix<'a, 'ast> {
778 /// Returns true only if some suffix of the module path for parent
779 /// matches `self.in_which`.
780 ///
781 /// In other words: let `[x_0,x_1,...,x_k]` be `self.in_which`;
782 /// returns true if parent's path ends with the suffix
783 /// `x_0::x_1::...::x_k`.
784 fn suffix_matches(&self, parent: NodeId) -> bool {
785 let mut cursor = parent;
786 for part in self.in_which.iter().rev() {
787 let (mod_id, mod_name) = match find_first_mod_parent(self.map, cursor) {
788 None => return false,
789 Some((node_id, name)) => (node_id, name),
790 };
791 if &part[..] != mod_name.as_str() {
792 return false;
793 }
794 cursor = self.map.get_parent(mod_id);
795 }
796 return true;
797
798 // Finds the first mod in parent chain for `id`, along with
799 // that mod's name.
800 //
801 // If `id` itself is a mod named `m` with parent `p`, then
802 // returns `Some(id, m, p)`. If `id` has no mod in its parent
803 // chain, then returns `None`.
804 fn find_first_mod_parent<'a>(map: &'a Map, mut id: NodeId) -> Option<(NodeId, Name)> {
805 loop {
806 match map.find(id) {
807 None => return None,
808 Some(NodeItem(item)) if item_is_mod(&item) =>
809 return Some((id, item.name)),
810 _ => {}
811 }
812 let parent = map.get_parent(id);
813 if parent == id { return None }
814 id = parent;
815 }
816
817 fn item_is_mod(item: &Item) -> bool {
818 match item.node {
819 ItemMod(_) => true,
820 _ => false,
821 }
822 }
823 }
824 }
825
826 // We are looking at some node `n` with a given name and parent
827 // id; do their names match what I am seeking?
828 fn matches_names(&self, parent_of_n: NodeId, name: Name) -> bool {
829 name.as_str() == &self.item_name[..] &&
830 self.suffix_matches(parent_of_n)
831 }
832 }
833
834 impl<'a, 'ast> Iterator for NodesMatchingSuffix<'a, 'ast> {
835 type Item = NodeId;
836
837 fn next(&mut self) -> Option<NodeId> {
838 loop {
839 let idx = self.idx;
840 if idx as usize >= self.map.entry_count() {
841 return None;
842 }
843 self.idx += 1;
844 let name = match self.map.find_entry(idx) {
845 Some(EntryItem(_, n)) => n.name(),
846 Some(EntryForeignItem(_, n))=> n.name(),
847 Some(EntryTraitItem(_, n)) => n.name(),
848 Some(EntryImplItem(_, n)) => n.name(),
849 Some(EntryVariant(_, n)) => n.name(),
850 _ => continue,
851 };
852 if self.matches_names(self.map.get_parent(idx), name) {
853 return Some(idx)
854 }
855 }
856 }
857 }
858
859 trait Named {
860 fn name(&self) -> Name;
861 }
862
863 impl<T:Named> Named for Spanned<T> { fn name(&self) -> Name { self.node.name() } }
864
865 impl Named for Item { fn name(&self) -> Name { self.name } }
866 impl Named for ForeignItem { fn name(&self) -> Name { self.name } }
867 impl Named for Variant_ { fn name(&self) -> Name { self.name } }
868 impl Named for TraitItem { fn name(&self) -> Name { self.name } }
869 impl Named for ImplItem { fn name(&self) -> Name { self.name } }
870
871 pub trait FoldOps {
872 fn new_id(&self, id: NodeId) -> NodeId {
873 id
874 }
875 fn new_def_id(&self, def_id: DefId) -> DefId {
876 def_id
877 }
878 fn new_span(&self, span: Span) -> Span {
879 span
880 }
881 }
882
883 /// A Folder that updates IDs and Span's according to fold_ops.
884 struct IdAndSpanUpdater<F> {
885 fold_ops: F
886 }
887
888 impl<F: FoldOps> Folder for IdAndSpanUpdater<F> {
889 fn new_id(&mut self, id: NodeId) -> NodeId {
890 self.fold_ops.new_id(id)
891 }
892
893 fn new_span(&mut self, span: Span) -> Span {
894 self.fold_ops.new_span(span)
895 }
896 }
897
898 pub fn map_crate<'ast>(forest: &'ast mut Forest) -> Map<'ast> {
899 let (map, definitions) = {
900 let mut collector = NodeCollector::root(&forest.krate);
901 intravisit::walk_crate(&mut collector, &forest.krate);
902 (collector.map, collector.definitions)
903 };
904
905 if log_enabled!(::log::DEBUG) {
906 // This only makes sense for ordered stores; note the
907 // enumerate to count the number of entries.
908 let (entries_less_1, _) = map.iter().filter(|&x| {
909 match *x {
910 NotPresent => false,
911 _ => true
912 }
913 }).enumerate().last().expect("AST map was empty after folding?");
914
915 let entries = entries_less_1 + 1;
916 let vector_length = map.len();
917 debug!("The AST map has {} entries with a maximum of {}: occupancy {:.1}%",
918 entries, vector_length, (entries as f64 / vector_length as f64) * 100.);
919 }
920
921 Map {
922 forest: forest,
923 dep_graph: forest.dep_graph.clone(),
924 map: RefCell::new(map),
925 definitions: RefCell::new(definitions),
926 }
927 }
928
929 /// Used for items loaded from external crate that are being inlined into this
930 /// crate.
931 pub fn map_decoded_item<'ast, F: FoldOps>(map: &Map<'ast>,
932 parent_path: Vec<PathElem>,
933 parent_def_path: DefPath,
934 ii: InlinedItem,
935 fold_ops: F)
936 -> &'ast InlinedItem {
937 let mut fld = IdAndSpanUpdater { fold_ops: fold_ops };
938 let ii = match ii {
939 II::Item(i) => II::Item(i.map(|i| fld.fold_item(i))),
940 II::TraitItem(d, ti) => {
941 II::TraitItem(fld.fold_ops.new_def_id(d),
942 ti.map(|ti| fld.fold_trait_item(ti)))
943 }
944 II::ImplItem(d, ii) => {
945 II::ImplItem(fld.fold_ops.new_def_id(d),
946 ii.map(|ii| fld.fold_impl_item(ii)))
947 }
948 II::Foreign(i) => II::Foreign(i.map(|i| fld.fold_foreign_item(i)))
949 };
950
951 let ii_parent = map.forest.inlined_items.alloc(InlinedParent {
952 path: parent_path,
953 ii: ii
954 });
955
956 let ii_parent_id = fld.new_id(DUMMY_NODE_ID);
957 let mut collector =
958 NodeCollector::extend(
959 map.krate(),
960 ii_parent,
961 ii_parent_id,
962 parent_def_path,
963 mem::replace(&mut *map.map.borrow_mut(), vec![]),
964 mem::replace(&mut *map.definitions.borrow_mut(), Definitions::new()));
965 ii_parent.ii.visit(&mut collector);
966
967 *map.map.borrow_mut() = collector.map;
968 *map.definitions.borrow_mut() = collector.definitions;
969
970 &ii_parent.ii
971 }
972
973 pub trait NodePrinter {
974 fn print_node(&mut self, node: &Node) -> io::Result<()>;
975 }
976
977 impl<'a> NodePrinter for pprust::State<'a> {
978 fn print_node(&mut self, node: &Node) -> io::Result<()> {
979 match *node {
980 NodeItem(a) => self.print_item(&a),
981 NodeForeignItem(a) => self.print_foreign_item(&a),
982 NodeTraitItem(a) => self.print_trait_item(a),
983 NodeImplItem(a) => self.print_impl_item(a),
984 NodeVariant(a) => self.print_variant(&a),
985 NodeExpr(a) => self.print_expr(&a),
986 NodeStmt(a) => self.print_stmt(&a),
987 NodePat(a) => self.print_pat(&a),
988 NodeBlock(a) => self.print_block(&a),
989 NodeLifetime(a) => self.print_lifetime(&a),
990 NodeTyParam(_) => panic!("cannot print TyParam"),
991 // these cases do not carry enough information in the
992 // ast_map to reconstruct their full structure for pretty
993 // printing.
994 NodeLocal(_) => panic!("cannot print isolated Local"),
995 NodeStructCtor(_) => panic!("cannot print isolated StructCtor"),
996 }
997 }
998 }
999
1000 fn node_id_to_string(map: &Map, id: NodeId, include_id: bool) -> String {
1001 let id_str = format!(" (id={})", id);
1002 let id_str = if include_id { &id_str[..] } else { "" };
1003
1004 match map.find(id) {
1005 Some(NodeItem(item)) => {
1006 let path_str = map.path_to_str_with_name(id, item.name);
1007 let item_str = match item.node {
1008 ItemExternCrate(..) => "extern crate",
1009 ItemUse(..) => "use",
1010 ItemStatic(..) => "static",
1011 ItemConst(..) => "const",
1012 ItemFn(..) => "fn",
1013 ItemMod(..) => "mod",
1014 ItemForeignMod(..) => "foreign mod",
1015 ItemTy(..) => "ty",
1016 ItemEnum(..) => "enum",
1017 ItemStruct(..) => "struct",
1018 ItemTrait(..) => "trait",
1019 ItemImpl(..) => "impl",
1020 ItemDefaultImpl(..) => "default impl",
1021 };
1022 format!("{} {}{}", item_str, path_str, id_str)
1023 }
1024 Some(NodeForeignItem(item)) => {
1025 let path_str = map.path_to_str_with_name(id, item.name);
1026 format!("foreign item {}{}", path_str, id_str)
1027 }
1028 Some(NodeImplItem(ii)) => {
1029 match ii.node {
1030 ImplItemKind::Const(..) => {
1031 format!("assoc const {} in {}{}",
1032 ii.name,
1033 map.path_to_string(id),
1034 id_str)
1035 }
1036 ImplItemKind::Method(..) => {
1037 format!("method {} in {}{}",
1038 ii.name,
1039 map.path_to_string(id), id_str)
1040 }
1041 ImplItemKind::Type(_) => {
1042 format!("assoc type {} in {}{}",
1043 ii.name,
1044 map.path_to_string(id),
1045 id_str)
1046 }
1047 }
1048 }
1049 Some(NodeTraitItem(ti)) => {
1050 let kind = match ti.node {
1051 ConstTraitItem(..) => "assoc constant",
1052 MethodTraitItem(..) => "trait method",
1053 TypeTraitItem(..) => "assoc type",
1054 };
1055
1056 format!("{} {} in {}{}",
1057 kind,
1058 ti.name,
1059 map.path_to_string(id),
1060 id_str)
1061 }
1062 Some(NodeVariant(ref variant)) => {
1063 format!("variant {} in {}{}",
1064 variant.node.name,
1065 map.path_to_string(id), id_str)
1066 }
1067 Some(NodeExpr(ref expr)) => {
1068 format!("expr {}{}", pprust::expr_to_string(&expr), id_str)
1069 }
1070 Some(NodeStmt(ref stmt)) => {
1071 format!("stmt {}{}", pprust::stmt_to_string(&stmt), id_str)
1072 }
1073 Some(NodeLocal(ref pat)) => {
1074 format!("local {}{}", pprust::pat_to_string(&pat), id_str)
1075 }
1076 Some(NodePat(ref pat)) => {
1077 format!("pat {}{}", pprust::pat_to_string(&pat), id_str)
1078 }
1079 Some(NodeBlock(ref block)) => {
1080 format!("block {}{}", pprust::block_to_string(&block), id_str)
1081 }
1082 Some(NodeStructCtor(_)) => {
1083 format!("struct_ctor {}{}", map.path_to_string(id), id_str)
1084 }
1085 Some(NodeLifetime(ref l)) => {
1086 format!("lifetime {}{}",
1087 pprust::lifetime_to_string(&l), id_str)
1088 }
1089 Some(NodeTyParam(ref ty_param)) => {
1090 format!("typaram {:?}{}", ty_param, id_str)
1091 }
1092 None => {
1093 format!("unknown node{}", id_str)
1094 }
1095 }
1096 }