src/librustc_driver/pretty.rs

   1 // Copyright 2014 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 //! The various pretty print routines.
  12
  13 pub use self::UserIdentifiedItem::*;
  14 pub use self::PpSourceMode::*;
  15 pub use self::PpMode::*;
  16 use self::NodesMatchingUII::*;
  17
  18 use rustc_trans::back::link;
  19
  20 use driver;
  21
  22 use rustc::middle::ty;
  23 use rustc::middle::cfg;
  24 use rustc::middle::cfg::graphviz::LabelledCFG;
  25 use rustc::session::Session;
  26 use rustc::session::config::Input;
  27 use rustc_borrowck as borrowck;
  28 use rustc_borrowck::graphviz as borrowck_dot;
  29 use rustc_resolve as resolve;
  30 use rustc_metadata::cstore::CStore;
  31
  32 use syntax::ast;
  33 use syntax::codemap;
  34 use syntax::fold::{self, Folder};
  35 use syntax::print::{pp, pprust};
  36 use syntax::print::pprust::PrintState;
  37 use syntax::ptr::P;
  38 use syntax::util::small_vector::SmallVector;
  39
  40 use graphviz as dot;
  41
  42 use std::fs::File;
  43 use std::io::{self, Write};
  44 use std::option;
  45 use std::path::PathBuf;
  46 use std::str::FromStr;
  47
  48 use rustc::front::map as hir_map;
  49 use rustc::front::map::{blocks, NodePrinter};
  50 use rustc_front::hir;
  51 use rustc_front::lowering::{lower_crate, LoweringContext};
  52 use rustc_front::print::pprust as pprust_hir;
  53
  54 #[derive(Copy, Clone, PartialEq, Debug)]
  55 pub enum PpSourceMode {
  56     PpmNormal,
  57     PpmEveryBodyLoops,
  58     PpmExpanded,
  59     PpmIdentified,
  60     PpmExpandedIdentified,
  61     PpmExpandedHygiene,
  62     PpmTyped,
  63 }
  64
  65 #[derive(Copy, Clone, PartialEq, Debug)]
  66 pub enum PpFlowGraphMode {
  67     Default,
  68     /// Drops the labels from the edges in the flowgraph output. This
  69     /// is mostly for use in the --unpretty flowgraph run-make tests,
  70     /// since the labels are largely uninteresting in those cases and
  71     /// have become a pain to maintain.
  72     UnlabelledEdges,
  73 }
  74 #[derive(Copy, Clone, PartialEq, Debug)]
  75 pub enum PpMode {
  76     PpmSource(PpSourceMode),
  77     PpmHir(PpSourceMode),
  78     PpmFlowGraph(PpFlowGraphMode),
  79 }
  80
  81 pub fn parse_pretty(sess: &Session,
  82                     name: &str,
  83                     extended: bool)
  84                     -> (PpMode, Option<UserIdentifiedItem>) {
  85     let mut split = name.splitn(2, '=');
  86     let first = split.next().unwrap();
  87     let opt_second = split.next();
  88     let first = match (first, extended) {
  89         ("normal", _) => PpmSource(PpmNormal),
  90         ("identified", _) => PpmSource(PpmIdentified),
  91         ("everybody_loops", true) => PpmSource(PpmEveryBodyLoops),
  92         ("expanded", _) => PpmSource(PpmExpanded),
  93         ("expanded,identified", _) => PpmSource(PpmExpandedIdentified),
  94         ("expanded,hygiene", _) => PpmSource(PpmExpandedHygiene),
  95         ("hir", true) => PpmHir(PpmNormal),
  96         ("hir,identified", true) => PpmHir(PpmIdentified),
  97         ("hir,typed", true) => PpmHir(PpmTyped),
  98         ("flowgraph", true) => PpmFlowGraph(PpFlowGraphMode::Default),
  99         ("flowgraph,unlabelled", true) => PpmFlowGraph(PpFlowGraphMode::UnlabelledEdges),
 100         _ => {
 101             if extended {
 102                 sess.fatal(&format!("argument to `unpretty` must be one of `normal`, \
 103                                      `expanded`, `flowgraph[,unlabelled]=<nodeid>`, \
 104                                      `identified`, `expanded,identified`, `everybody_loops`, \
 105                                      `hir`, `hir,identified`, or `hir,typed`; got {}",
 106                                     name));
 107             } else {
 108                 sess.fatal(&format!("argument to `pretty` must be one of `normal`, `expanded`, \
 109                                      `identified`, or `expanded,identified`; got {}",
 110                                     name));
 111             }
 112         }
 113     };
 114     let opt_second = opt_second.and_then(|s| s.parse::<UserIdentifiedItem>().ok());
 115     (first, opt_second)
 116 }
 117
 118
 119
 120 // This slightly awkward construction is to allow for each PpMode to
 121 // choose whether it needs to do analyses (which can consume the
 122 // Session) and then pass through the session (now attached to the
 123 // analysis results) on to the chosen pretty-printer, along with the
 124 // `&PpAnn` object.
 125 //
 126 // Note that since the `&PrinterSupport` is freshly constructed on each
 127 // call, it would not make sense to try to attach the lifetime of `self`
 128 // to the lifetime of the `&PrinterObject`.
 129 //
 130 // (The `use_once_payload` is working around the current lack of once
 131 // functions in the compiler.)
 132
 133 impl PpSourceMode {
 134     /// Constructs a `PrinterSupport` object and passes it to `f`.
 135     fn call_with_pp_support<'tcx, A, B, F>(&self,
 136                                            sess: &'tcx Session,
 137                                            ast_map: Option<hir_map::Map<'tcx>>,
 138                                            payload: B,
 139                                            f: F)
 140                                            -> A
 141         where F: FnOnce(&PrinterSupport, B) -> A
 142     {
 143         match *self {
 144             PpmNormal | PpmEveryBodyLoops | PpmExpanded => {
 145                 let annotation = NoAnn {
 146                     sess: sess,
 147                     ast_map: ast_map,
 148                 };
 149                 f(&annotation, payload)
 150             }
 151
 152             PpmIdentified | PpmExpandedIdentified => {
 153                 let annotation = IdentifiedAnnotation {
 154                     sess: sess,
 155                     ast_map: ast_map,
 156                 };
 157                 f(&annotation, payload)
 158             }
 159             PpmExpandedHygiene => {
 160                 let annotation = HygieneAnnotation {
 161                     sess: sess,
 162                     ast_map: ast_map,
 163                 };
 164                 f(&annotation, payload)
 165             }
 166             _ => panic!("Should use call_with_pp_support_hir"),
 167         }
 168     }
 169     fn call_with_pp_support_hir<'tcx, A, B, F>(&self,
 170                                                sess: &'tcx Session,
 171                                                cstore: &CStore,
 172                                                ast_map: &hir_map::Map<'tcx>,
 173                                                arenas: &'tcx ty::CtxtArenas<'tcx>,
 174                                                id: &str,
 175                                                payload: B,
 176                                                f: F)
 177                                                -> A
 178         where F: FnOnce(&HirPrinterSupport, B, &hir::Crate) -> A
 179     {
 180         match *self {
 181             PpmNormal => {
 182                 let annotation = NoAnn {
 183                     sess: sess,
 184                     ast_map: Some(ast_map.clone()),
 185                 };
 186                 f(&annotation, payload, &ast_map.forest.krate)
 187             }
 188
 189             PpmIdentified => {
 190                 let annotation = IdentifiedAnnotation {
 191                     sess: sess,
 192                     ast_map: Some(ast_map.clone()),
 193                 };
 194                 f(&annotation, payload, &ast_map.forest.krate)
 195             }
 196             PpmTyped => {
 197                 driver::phase_3_run_analysis_passes(sess,
 198                                                     cstore,
 199                                                     ast_map.clone(),
 200                                                     arenas,
 201                                                     id,
 202                                                     resolve::MakeGlobMap::No,
 203                                                     |tcx, _, _| {
 204                                                         let annotation = TypedAnnotation {
 205                                                             tcx: tcx,
 206                                                         };
 207                                                         let _ignore = tcx.dep_graph.in_ignore();
 208                                                         f(&annotation,
 209                                                           payload,
 210                                                           &ast_map.forest.krate)
 211                                                     })
 212             }
 213             _ => panic!("Should use call_with_pp_support"),
 214         }
 215     }
 216 }
 217
 218 trait PrinterSupport<'ast>: pprust::PpAnn {
 219     /// Provides a uniform interface for re-extracting a reference to a
 220     /// `Session` from a value that now owns it.
 221     fn sess<'a>(&'a self) -> &'a Session;
 222
 223     /// Provides a uniform interface for re-extracting a reference to an
 224     /// `hir_map::Map` from a value that now owns it.
 225     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>>;
 226
 227     /// Produces the pretty-print annotation object.
 228     ///
 229     /// (Rust does not yet support upcasting from a trait object to
 230     /// an object for one of its super-traits.)
 231     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn;
 232 }
 233
 234 trait HirPrinterSupport<'ast>: pprust_hir::PpAnn {
 235     /// Provides a uniform interface for re-extracting a reference to a
 236     /// `Session` from a value that now owns it.
 237     fn sess<'a>(&'a self) -> &'a Session;
 238
 239     /// Provides a uniform interface for re-extracting a reference to an
 240     /// `hir_map::Map` from a value that now owns it.
 241     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>>;
 242
 243     /// Produces the pretty-print annotation object.
 244     ///
 245     /// (Rust does not yet support upcasting from a trait object to
 246     /// an object for one of its super-traits.)
 247     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn;
 248 }
 249
 250 struct NoAnn<'ast> {
 251     sess: &'ast Session,
 252     ast_map: Option<hir_map::Map<'ast>>,
 253 }
 254
 255 impl<'ast> PrinterSupport<'ast> for NoAnn<'ast> {
 256     fn sess<'a>(&'a self) -> &'a Session {
 257         self.sess
 258     }
 259
 260     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 261         self.ast_map.as_ref()
 262     }
 263
 264     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn {
 265         self
 266     }
 267 }
 268
 269 impl<'ast> HirPrinterSupport<'ast> for NoAnn<'ast> {
 270     fn sess<'a>(&'a self) -> &'a Session {
 271         self.sess
 272     }
 273
 274     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 275         self.ast_map.as_ref()
 276     }
 277
 278     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn {
 279         self
 280     }
 281 }
 282
 283 impl<'ast> pprust::PpAnn for NoAnn<'ast> {}
 284 impl<'ast> pprust_hir::PpAnn for NoAnn<'ast> {}
 285
 286 struct IdentifiedAnnotation<'ast> {
 287     sess: &'ast Session,
 288     ast_map: Option<hir_map::Map<'ast>>,
 289 }
 290
 291 impl<'ast> PrinterSupport<'ast> for IdentifiedAnnotation<'ast> {
 292     fn sess<'a>(&'a self) -> &'a Session {
 293         self.sess
 294     }
 295
 296     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 297         self.ast_map.as_ref()
 298     }
 299
 300     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn {
 301         self
 302     }
 303 }
 304
 305 impl<'ast> pprust::PpAnn for IdentifiedAnnotation<'ast> {
 306     fn pre(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 307         match node {
 308             pprust::NodeExpr(_) => s.popen(),
 309             _ => Ok(()),
 310         }
 311     }
 312     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 313         match node {
 314             pprust::NodeIdent(_) | pprust::NodeName(_) => Ok(()),
 315
 316             pprust::NodeItem(item) => {
 317                 try!(pp::space(&mut s.s));
 318                 s.synth_comment(item.id.to_string())
 319             }
 320             pprust::NodeSubItem(id) => {
 321                 try!(pp::space(&mut s.s));
 322                 s.synth_comment(id.to_string())
 323             }
 324             pprust::NodeBlock(blk) => {
 325                 try!(pp::space(&mut s.s));
 326                 s.synth_comment(format!("block {}", blk.id))
 327             }
 328             pprust::NodeExpr(expr) => {
 329                 try!(pp::space(&mut s.s));
 330                 try!(s.synth_comment(expr.id.to_string()));
 331                 s.pclose()
 332             }
 333             pprust::NodePat(pat) => {
 334                 try!(pp::space(&mut s.s));
 335                 s.synth_comment(format!("pat {}", pat.id))
 336             }
 337         }
 338     }
 339 }
 340
 341 impl<'ast> HirPrinterSupport<'ast> for IdentifiedAnnotation<'ast> {
 342     fn sess<'a>(&'a self) -> &'a Session {
 343         self.sess
 344     }
 345
 346     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 347         self.ast_map.as_ref()
 348     }
 349
 350     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn {
 351         self
 352     }
 353 }
 354
 355 impl<'ast> pprust_hir::PpAnn for IdentifiedAnnotation<'ast> {
 356     fn pre(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 357         match node {
 358             pprust_hir::NodeExpr(_) => s.popen(),
 359             _ => Ok(()),
 360         }
 361     }
 362     fn post(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 363         match node {
 364             pprust_hir::NodeName(_) => Ok(()),
 365             pprust_hir::NodeItem(item) => {
 366                 try!(pp::space(&mut s.s));
 367                 s.synth_comment(item.id.to_string())
 368             }
 369             pprust_hir::NodeSubItem(id) => {
 370                 try!(pp::space(&mut s.s));
 371                 s.synth_comment(id.to_string())
 372             }
 373             pprust_hir::NodeBlock(blk) => {
 374                 try!(pp::space(&mut s.s));
 375                 s.synth_comment(format!("block {}", blk.id))
 376             }
 377             pprust_hir::NodeExpr(expr) => {
 378                 try!(pp::space(&mut s.s));
 379                 try!(s.synth_comment(expr.id.to_string()));
 380                 s.pclose()
 381             }
 382             pprust_hir::NodePat(pat) => {
 383                 try!(pp::space(&mut s.s));
 384                 s.synth_comment(format!("pat {}", pat.id))
 385             }
 386         }
 387     }
 388 }
 389
 390 struct HygieneAnnotation<'ast> {
 391     sess: &'ast Session,
 392     ast_map: Option<hir_map::Map<'ast>>,
 393 }
 394
 395 impl<'ast> PrinterSupport<'ast> for HygieneAnnotation<'ast> {
 396     fn sess<'a>(&'a self) -> &'a Session {
 397         self.sess
 398     }
 399
 400     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 401         self.ast_map.as_ref()
 402     }
 403
 404     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn {
 405         self
 406     }
 407 }
 408
 409 impl<'ast> pprust::PpAnn for HygieneAnnotation<'ast> {
 410     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 411         match node {
 412             pprust::NodeIdent(&ast::Ident { name: ast::Name(nm), ctxt }) => {
 413                 try!(pp::space(&mut s.s));
 414                 // FIXME #16420: this doesn't display the connections
 415                 // between syntax contexts
 416                 s.synth_comment(format!("{}#{}", nm, ctxt.0))
 417             }
 418             pprust::NodeName(&ast::Name(nm)) => {
 419                 try!(pp::space(&mut s.s));
 420                 s.synth_comment(nm.to_string())
 421             }
 422             _ => Ok(()),
 423         }
 424     }
 425 }
 426
 427
 428 struct TypedAnnotation<'a, 'tcx: 'a> {
 429     tcx: &'a ty::ctxt<'tcx>,
 430 }
 431
 432 impl<'b, 'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'b, 'tcx> {
 433     fn sess<'a>(&'a self) -> &'a Session {
 434         &self.tcx.sess
 435     }
 436
 437     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'tcx>> {
 438         Some(&self.tcx.map)
 439     }
 440
 441     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn {
 442         self
 443     }
 444 }
 445
 446 impl<'a, 'tcx> pprust_hir::PpAnn for TypedAnnotation<'a, 'tcx> {
 447     fn pre(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 448         match node {
 449             pprust_hir::NodeExpr(_) => s.popen(),
 450             _ => Ok(()),
 451         }
 452     }
 453     fn post(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 454         match node {
 455             pprust_hir::NodeExpr(expr) => {
 456                 try!(pp::space(&mut s.s));
 457                 try!(pp::word(&mut s.s, "as"));
 458                 try!(pp::space(&mut s.s));
 459                 try!(pp::word(&mut s.s, &self.tcx.expr_ty(expr).to_string()));
 460                 s.pclose()
 461             }
 462             _ => Ok(()),
 463         }
 464     }
 465 }
 466
 467 fn gather_flowgraph_variants(sess: &Session) -> Vec<borrowck_dot::Variant> {
 468     let print_loans = sess.opts.debugging_opts.flowgraph_print_loans;
 469     let print_moves = sess.opts.debugging_opts.flowgraph_print_moves;
 470     let print_assigns = sess.opts.debugging_opts.flowgraph_print_assigns;
 471     let print_all = sess.opts.debugging_opts.flowgraph_print_all;
 472     let mut variants = Vec::new();
 473     if print_all || print_loans {
 474         variants.push(borrowck_dot::Loans);
 475     }
 476     if print_all || print_moves {
 477         variants.push(borrowck_dot::Moves);
 478     }
 479     if print_all || print_assigns {
 480         variants.push(borrowck_dot::Assigns);
 481     }
 482     variants
 483 }
 484
 485 #[derive(Clone, Debug)]
 486 pub enum UserIdentifiedItem {
 487     ItemViaNode(ast::NodeId),
 488     ItemViaPath(Vec<String>),
 489 }
 490
 491 impl FromStr for UserIdentifiedItem {
 492     type Err = ();
 493     fn from_str(s: &str) -> Result<UserIdentifiedItem, ()> {
 494         Ok(s.parse()
 495             .map(ItemViaNode)
 496             .unwrap_or_else(|_| ItemViaPath(s.split("::").map(|s| s.to_string()).collect())))
 497     }
 498 }
 499
 500 enum NodesMatchingUII<'a, 'ast: 'a> {
 501     NodesMatchingDirect(option::IntoIter<ast::NodeId>),
 502     NodesMatchingSuffix(hir_map::NodesMatchingSuffix<'a, 'ast>),
 503 }
 504
 505 impl<'a, 'ast> Iterator for NodesMatchingUII<'a, 'ast> {
 506     type Item = ast::NodeId;
 507
 508     fn next(&mut self) -> Option<ast::NodeId> {
 509         match self {
 510             &mut NodesMatchingDirect(ref mut iter) => iter.next(),
 511             &mut NodesMatchingSuffix(ref mut iter) => iter.next(),
 512         }
 513     }
 514 }
 515
 516 impl UserIdentifiedItem {
 517     fn reconstructed_input(&self) -> String {
 518         match *self {
 519             ItemViaNode(node_id) => node_id.to_string(),
 520             ItemViaPath(ref parts) => parts.join("::"),
 521         }
 522     }
 523
 524     fn all_matching_node_ids<'a, 'ast>(&'a self,
 525                                        map: &'a hir_map::Map<'ast>)
 526                                        -> NodesMatchingUII<'a, 'ast> {
 527         match *self {
 528             ItemViaNode(node_id) => NodesMatchingDirect(Some(node_id).into_iter()),
 529             ItemViaPath(ref parts) => NodesMatchingSuffix(map.nodes_matching_suffix(&parts[..])),
 530         }
 531     }
 532
 533     fn to_one_node_id(self, user_option: &str, sess: &Session, map: &hir_map::Map) -> ast::NodeId {
 534         let fail_because = |is_wrong_because| -> ast::NodeId {
 535             let message = format!("{} needs NodeId (int) or unique path suffix (b::c::d); got \
 536                                    {}, which {}",
 537                                   user_option,
 538                                   self.reconstructed_input(),
 539                                   is_wrong_because);
 540             sess.fatal(&message[..])
 541         };
 542
 543         let mut saw_node = ast::DUMMY_NODE_ID;
 544         let mut seen = 0;
 545         for node in self.all_matching_node_ids(map) {
 546             saw_node = node;
 547             seen += 1;
 548             if seen > 1 {
 549                 fail_because("does not resolve uniquely");
 550             }
 551         }
 552         if seen == 0 {
 553             fail_because("does not resolve to any item");
 554         }
 555
 556         assert!(seen == 1);
 557         return saw_node;
 558     }
 559 }
 560
 561 fn needs_ast_map(ppm: &PpMode, opt_uii: &Option<UserIdentifiedItem>) -> bool {
 562     match *ppm {
 563         PpmSource(PpmNormal) |
 564         PpmSource(PpmEveryBodyLoops) |
 565         PpmSource(PpmIdentified) => opt_uii.is_some(),
 566
 567         PpmSource(PpmExpanded) |
 568         PpmSource(PpmExpandedIdentified) |
 569         PpmSource(PpmExpandedHygiene) |
 570         PpmHir(_) |
 571         PpmFlowGraph(_) => true,
 572         PpmSource(PpmTyped) => panic!("invalid state"),
 573     }
 574 }
 575
 576 fn needs_expansion(ppm: &PpMode) -> bool {
 577     match *ppm {
 578         PpmSource(PpmNormal) |
 579         PpmSource(PpmEveryBodyLoops) |
 580         PpmSource(PpmIdentified) => false,
 581
 582         PpmSource(PpmExpanded) |
 583         PpmSource(PpmExpandedIdentified) |
 584         PpmSource(PpmExpandedHygiene) |
 585         PpmHir(_) |
 586         PpmFlowGraph(_) => true,
 587         PpmSource(PpmTyped) => panic!("invalid state"),
 588     }
 589 }
 590
 591 struct ReplaceBodyWithLoop {
 592     within_static_or_const: bool,
 593 }
 594
 595 impl ReplaceBodyWithLoop {
 596     fn new() -> ReplaceBodyWithLoop {
 597         ReplaceBodyWithLoop { within_static_or_const: false }
 598     }
 599 }
 600
 601 impl fold::Folder for ReplaceBodyWithLoop {
 602     fn fold_item_underscore(&mut self, i: ast::Item_) -> ast::Item_ {
 603         match i {
 604             ast::ItemStatic(..) | ast::ItemConst(..) => {
 605                 self.within_static_or_const = true;
 606                 let ret = fold::noop_fold_item_underscore(i, self);
 607                 self.within_static_or_const = false;
 608                 return ret;
 609             }
 610             _ => {
 611                 fold::noop_fold_item_underscore(i, self)
 612             }
 613         }
 614     }
 615
 616     fn fold_trait_item(&mut self, i: P<ast::TraitItem>) -> SmallVector<P<ast::TraitItem>> {
 617         match i.node {
 618             ast::ConstTraitItem(..) => {
 619                 self.within_static_or_const = true;
 620                 let ret = fold::noop_fold_trait_item(i, self);
 621                 self.within_static_or_const = false;
 622                 return ret;
 623             }
 624             _ => fold::noop_fold_trait_item(i, self),
 625         }
 626     }
 627
 628     fn fold_impl_item(&mut self, i: P<ast::ImplItem>) -> SmallVector<P<ast::ImplItem>> {
 629         match i.node {
 630             ast::ImplItemKind::Const(..) => {
 631                 self.within_static_or_const = true;
 632                 let ret = fold::noop_fold_impl_item(i, self);
 633                 self.within_static_or_const = false;
 634                 return ret;
 635             }
 636             _ => fold::noop_fold_impl_item(i, self),
 637         }
 638     }
 639
 640     fn fold_block(&mut self, b: P<ast::Block>) -> P<ast::Block> {
 641         fn expr_to_block(rules: ast::BlockCheckMode, e: Option<P<ast::Expr>>) -> P<ast::Block> {
 642             P(ast::Block {
 643                 expr: e,
 644                 stmts: vec![],
 645                 rules: rules,
 646                 id: ast::DUMMY_NODE_ID,
 647                 span: codemap::DUMMY_SP,
 648             })
 649         }
 650
 651         if !self.within_static_or_const {
 652
 653             let empty_block = expr_to_block(ast::DefaultBlock, None);
 654             let loop_expr = P(ast::Expr {
 655                 node: ast::ExprLoop(empty_block, None),
 656                 id: ast::DUMMY_NODE_ID,
 657                 span: codemap::DUMMY_SP,
 658                 attrs: None,
 659             });
 660
 661             expr_to_block(b.rules, Some(loop_expr))
 662
 663         } else {
 664             fold::noop_fold_block(b, self)
 665         }
 666     }
 667
 668     // in general the pretty printer processes unexpanded code, so
 669     // we override the default `fold_mac` method which panics.
 670     fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac {
 671         fold::noop_fold_mac(mac, self)
 672     }
 673 }
 674
 675 pub fn pretty_print_input(sess: Session,
 676                           cstore: &CStore,
 677                           cfg: ast::CrateConfig,
 678                           input: &Input,
 679                           ppm: PpMode,
 680                           opt_uii: Option<UserIdentifiedItem>,
 681                           ofile: Option<PathBuf>) {
 682     let krate = driver::phase_1_parse_input(&sess, cfg, input);
 683
 684     let krate = if let PpmSource(PpmEveryBodyLoops) = ppm {
 685         let mut fold = ReplaceBodyWithLoop::new();
 686         fold.fold_crate(krate)
 687     } else {
 688         krate
 689     };
 690
 691     let id = link::find_crate_name(Some(&sess), &krate.attrs, input);
 692
 693     let is_expanded = needs_expansion(&ppm);
 694     let compute_ast_map = needs_ast_map(&ppm, &opt_uii);
 695     let krate = if compute_ast_map {
 696         match driver::phase_2_configure_and_expand(&sess, &cstore, krate, &id[..], None) {
 697             None => return,
 698             Some(k) => driver::assign_node_ids(&sess, k),
 699         }
 700     } else {
 701         krate
 702     };
 703
 704     // There is some twisted, god-forsaken tangle of lifetimes here which makes
 705     // the ordering of stuff super-finicky.
 706     let mut hir_forest;
 707     let lcx = LoweringContext::new(&sess, Some(&krate));
 708     let arenas = ty::CtxtArenas::new();
 709     let ast_map = if compute_ast_map {
 710         hir_forest = hir_map::Forest::new(lower_crate(&lcx, &krate));
 711         let map = driver::make_map(&sess, &mut hir_forest);
 712         Some(map)
 713     } else {
 714         None
 715     };
 716
 717     let src_name = driver::source_name(input);
 718     let src = sess.codemap()
 719                   .get_filemap(&src_name[..])
 720                   .src
 721                   .as_ref()
 722                   .unwrap()
 723                   .as_bytes()
 724                   .to_vec();
 725     let mut rdr = &src[..];
 726
 727     let mut out = Vec::new();
 728
 729     match (ppm, opt_uii) {
 730         (PpmSource(s), _) => {
 731             // Silently ignores an identified node.
 732             let out: &mut Write = &mut out;
 733             s.call_with_pp_support(&sess, ast_map, box out, |annotation, out| {
 734                 debug!("pretty printing source code {:?}", s);
 735                 let sess = annotation.sess();
 736                 pprust::print_crate(sess.codemap(),
 737                                     sess.diagnostic(),
 738                                     &krate,
 739                                     src_name.to_string(),
 740                                     &mut rdr,
 741                                     out,
 742                                     annotation.pp_ann(),
 743                                     is_expanded)
 744             })
 745         }
 746
 747         (PpmHir(s), None) => {
 748             let out: &mut Write = &mut out;
 749             s.call_with_pp_support_hir(&sess,
 750                                        cstore,
 751                                        &ast_map.unwrap(),
 752                                        &arenas,
 753                                        &id,
 754                                        box out,
 755                                        |annotation, out, krate| {
 756                                            debug!("pretty printing source code {:?}", s);
 757                                            let sess = annotation.sess();
 758                                            pprust_hir::print_crate(sess.codemap(),
 759                                                                    sess.diagnostic(),
 760                                                                    krate,
 761                                                                    src_name.to_string(),
 762                                                                    &mut rdr,
 763                                                                    out,
 764                                                                    annotation.pp_ann(),
 765                                                                    is_expanded)
 766                                        })
 767         }
 768
 769         (PpmHir(s), Some(uii)) => {
 770             let out: &mut Write = &mut out;
 771             s.call_with_pp_support_hir(&sess,
 772                                        cstore,
 773                                        &ast_map.unwrap(),
 774                                        &arenas,
 775                                        &id,
 776                                        (out,uii),
 777                                        |annotation, (out,uii), _| {
 778                 debug!("pretty printing source code {:?}", s);
 779                 let sess = annotation.sess();
 780                 let ast_map = annotation.ast_map().expect("--pretty missing ast_map");
 781                 let mut pp_state =
 782                     pprust_hir::State::new_from_input(sess.codemap(),
 783                                                       sess.diagnostic(),
 784                                                       src_name.to_string(),
 785                                                       &mut rdr,
 786                                                       box out,
 787                                                       annotation.pp_ann(),
 788                                                       true,
 789                                                       Some(ast_map.krate()));
 790                 for node_id in uii.all_matching_node_ids(ast_map) {
 791                     let node = ast_map.get(node_id);
 792                     try!(pp_state.print_node(&node));
 793                     try!(pp::space(&mut pp_state.s));
 794                     try!(pp_state.synth_comment(ast_map.path_to_string(node_id)));
 795                     try!(pp::hardbreak(&mut pp_state.s));
 796                 }
 797                 pp::eof(&mut pp_state.s)
 798             })
 799         }
 800
 801         (PpmFlowGraph(mode), opt_uii) => {
 802             debug!("pretty printing flow graph for {:?}", opt_uii);
 803             let uii = opt_uii.unwrap_or_else(|| {
 804                 sess.fatal(&format!("`pretty flowgraph=..` needs NodeId (int) or
 805                                      \
 806                                      unique path suffix (b::c::d)"))
 807
 808             });
 809             let ast_map = ast_map.expect("--pretty flowgraph missing ast_map");
 810             let nodeid = uii.to_one_node_id("--pretty", &sess, &ast_map);
 811
 812             let node = ast_map.find(nodeid).unwrap_or_else(|| {
 813                 sess.fatal(&format!("--pretty flowgraph couldn't find id: {}", nodeid))
 814             });
 815
 816             let code = blocks::Code::from_node(node);
 817             let out: &mut Write = &mut out;
 818             match code {
 819                 Some(code) => {
 820                     let variants = gather_flowgraph_variants(&sess);
 821                     driver::phase_3_run_analysis_passes(&sess,
 822                                                         &cstore,
 823                                                         ast_map,
 824                                                         &arenas,
 825                                                         &id,
 826                                                         resolve::MakeGlobMap::No,
 827                                                         |tcx, _, _| {
 828                                                             print_flowgraph(variants,
 829                                                                             tcx,
 830                                                                             code,
 831                                                                             mode,
 832                                                                             out)
 833                                                         })
 834                 }
 835                 None => {
 836                     let message = format!("--pretty=flowgraph needs block, fn, or method; got \
 837                                            {:?}",
 838                                           node);
 839
 840                     // point to what was found, if there's an
 841                     // accessible span.
 842                     match ast_map.opt_span(nodeid) {
 843                         Some(sp) => sess.span_fatal(sp, &message[..]),
 844                         None => sess.fatal(&message[..]),
 845                     }
 846                 }
 847             }
 848         }
 849     }
 850     .unwrap();
 851
 852     match ofile {
 853         None => print!("{}", String::from_utf8(out).unwrap()),
 854         Some(p) => {
 855             match File::create(&p) {
 856                 Ok(mut w) => w.write_all(&out).unwrap(),
 857                 Err(e) => panic!("print-print failed to open {} due to {}", p.display(), e),
 858             }
 859         }
 860     }
 861 }
 862
 863 fn print_flowgraph<W: Write>(variants: Vec<borrowck_dot::Variant>,
 864                              tcx: &ty::ctxt,
 865                              code: blocks::Code,
 866                              mode: PpFlowGraphMode,
 867                              mut out: W)
 868                              -> io::Result<()> {
 869     let cfg = match code {
 870         blocks::BlockCode(block) => cfg::CFG::new(tcx, &*block),
 871         blocks::FnLikeCode(fn_like) => cfg::CFG::new(tcx, &*fn_like.body()),
 872     };
 873     let labelled_edges = mode != PpFlowGraphMode::UnlabelledEdges;
 874     let lcfg = LabelledCFG {
 875         ast_map: &tcx.map,
 876         cfg: &cfg,
 877         name: format!("node_{}", code.id()),
 878         labelled_edges: labelled_edges,
 879     };
 880
 881     match code {
 882         _ if variants.is_empty() => {
 883             let r = dot::render(&lcfg, &mut out);
 884             return expand_err_details(r);
 885         }
 886         blocks::BlockCode(_) => {
 887             tcx.sess.err("--pretty flowgraph with -Z flowgraph-print annotations requires \
 888                           fn-like node id.");
 889             return Ok(());
 890         }
 891         blocks::FnLikeCode(fn_like) => {
 892             let (bccx, analysis_data) =
 893                 borrowck::build_borrowck_dataflow_data_for_fn(tcx,
 894                                                               fn_like.to_fn_parts(),
 895                                                               &cfg);
 896
 897             let lcfg = borrowck_dot::DataflowLabeller {
 898                 inner: lcfg,
 899                 variants: variants,
 900                 borrowck_ctxt: &bccx,
 901                 analysis_data: &analysis_data,
 902             };
 903             let r = dot::render(&lcfg, &mut out);
 904             return expand_err_details(r);
 905         }
 906     }
 907
 908     fn expand_err_details(r: io::Result<()>) -> io::Result<()> {
 909         r.map_err(|ioerr| {
 910             io::Error::new(io::ErrorKind::Other,
 911                            &format!("graphviz::render failed: {}", ioerr)[..])
 912         })
 913     }
 914 }