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, abort_on_err};
  21
  22 use rustc::dep_graph::DepGraph;
  23 use rustc::middle::ty;
  24 use rustc::middle::cfg;
  25 use rustc::middle::cfg::graphviz::LabelledCFG;
  26 use rustc::session::Session;
  27 use rustc::session::config::Input;
  28 use rustc_borrowck as borrowck;
  29 use rustc_borrowck::graphviz as borrowck_dot;
  30 use rustc_resolve as resolve;
  31 use rustc_metadata::cstore::CStore;
  32
  33 use syntax::ast::{self, BlockCheckMode};
  34 use syntax::codemap;
  35 use syntax::fold::{self, Folder};
  36 use syntax::print::{pp, pprust};
  37 use syntax::print::pprust::PrintState;
  38 use syntax::ptr::P;
  39 use syntax::util::small_vector::SmallVector;
  40
  41 use graphviz as dot;
  42
  43 use std::fs::File;
  44 use std::io::{self, Write};
  45 use std::option;
  46 use std::path::PathBuf;
  47 use std::str::FromStr;
  48
  49 use rustc::front::map as hir_map;
  50 use rustc::front::map::{blocks, NodePrinter};
  51 use rustc_front::hir;
  52 use rustc_front::lowering::{lower_crate, LoweringContext};
  53 use rustc_front::print::pprust as pprust_hir;
  54
  55 #[derive(Copy, Clone, PartialEq, Debug)]
  56 pub enum PpSourceMode {
  57     PpmNormal,
  58     PpmEveryBodyLoops,
  59     PpmExpanded,
  60     PpmIdentified,
  61     PpmExpandedIdentified,
  62     PpmExpandedHygiene,
  63     PpmTyped,
  64 }
  65
  66 #[derive(Copy, Clone, PartialEq, Debug)]
  67 pub enum PpFlowGraphMode {
  68     Default,
  69     /// Drops the labels from the edges in the flowgraph output. This
  70     /// is mostly for use in the --unpretty flowgraph run-make tests,
  71     /// since the labels are largely uninteresting in those cases and
  72     /// have become a pain to maintain.
  73     UnlabelledEdges,
  74 }
  75 #[derive(Copy, Clone, PartialEq, Debug)]
  76 pub enum PpMode {
  77     PpmSource(PpSourceMode),
  78     PpmHir(PpSourceMode),
  79     PpmFlowGraph(PpFlowGraphMode),
  80 }
  81
  82 pub fn parse_pretty(sess: &Session,
  83                     name: &str,
  84                     extended: bool)
  85                     -> (PpMode, Option<UserIdentifiedItem>) {
  86     let mut split = name.splitn(2, '=');
  87     let first = split.next().unwrap();
  88     let opt_second = split.next();
  89     let first = match (first, extended) {
  90         ("normal", _) => PpmSource(PpmNormal),
  91         ("identified", _) => PpmSource(PpmIdentified),
  92         ("everybody_loops", true) => PpmSource(PpmEveryBodyLoops),
  93         ("expanded", _) => PpmSource(PpmExpanded),
  94         ("expanded,identified", _) => PpmSource(PpmExpandedIdentified),
  95         ("expanded,hygiene", _) => PpmSource(PpmExpandedHygiene),
  96         ("hir", true) => PpmHir(PpmNormal),
  97         ("hir,identified", true) => PpmHir(PpmIdentified),
  98         ("hir,typed", true) => PpmHir(PpmTyped),
  99         ("flowgraph", true) => PpmFlowGraph(PpFlowGraphMode::Default),
 100         ("flowgraph,unlabelled", true) => PpmFlowGraph(PpFlowGraphMode::UnlabelledEdges),
 101         _ => {
 102             if extended {
 103                 sess.fatal(&format!("argument to `unpretty` must be one of `normal`, \
 104                                      `expanded`, `flowgraph[,unlabelled]=<nodeid>`, \
 105                                      `identified`, `expanded,identified`, `everybody_loops`, \
 106                                      `hir`, `hir,identified`, or `hir,typed`; got {}",
 107                                     name));
 108             } else {
 109                 sess.fatal(&format!("argument to `pretty` must be one of `normal`, `expanded`, \
 110                                      `identified`, or `expanded,identified`; got {}",
 111                                     name));
 112             }
 113         }
 114     };
 115     let opt_second = opt_second.and_then(|s| s.parse::<UserIdentifiedItem>().ok());
 116     (first, opt_second)
 117 }
 118
 119
 120
 121 // This slightly awkward construction is to allow for each PpMode to
 122 // choose whether it needs to do analyses (which can consume the
 123 // Session) and then pass through the session (now attached to the
 124 // analysis results) on to the chosen pretty-printer, along with the
 125 // `&PpAnn` object.
 126 //
 127 // Note that since the `&PrinterSupport` is freshly constructed on each
 128 // call, it would not make sense to try to attach the lifetime of `self`
 129 // to the lifetime of the `&PrinterObject`.
 130 //
 131 // (The `use_once_payload` is working around the current lack of once
 132 // functions in the compiler.)
 133
 134 impl PpSourceMode {
 135     /// Constructs a `PrinterSupport` object and passes it to `f`.
 136     fn call_with_pp_support<'tcx, A, B, F>(&self,
 137                                            sess: &'tcx Session,
 138                                            ast_map: Option<hir_map::Map<'tcx>>,
 139                                            payload: B,
 140                                            f: F)
 141                                            -> A
 142         where F: FnOnce(&PrinterSupport, B) -> A
 143     {
 144         match *self {
 145             PpmNormal | PpmEveryBodyLoops | PpmExpanded => {
 146                 let annotation = NoAnn {
 147                     sess: sess,
 148                     ast_map: ast_map,
 149                 };
 150                 f(&annotation, payload)
 151             }
 152
 153             PpmIdentified | PpmExpandedIdentified => {
 154                 let annotation = IdentifiedAnnotation {
 155                     sess: sess,
 156                     ast_map: ast_map,
 157                 };
 158                 f(&annotation, payload)
 159             }
 160             PpmExpandedHygiene => {
 161                 let annotation = HygieneAnnotation {
 162                     sess: sess,
 163                     ast_map: ast_map,
 164                 };
 165                 f(&annotation, payload)
 166             }
 167             _ => panic!("Should use call_with_pp_support_hir"),
 168         }
 169     }
 170     fn call_with_pp_support_hir<'tcx, A, B, F>(&self,
 171                                                sess: &'tcx Session,
 172                                                cstore: &CStore,
 173                                                ast_map: &hir_map::Map<'tcx>,
 174                                                arenas: &'tcx ty::CtxtArenas<'tcx>,
 175                                                id: &str,
 176                                                payload: B,
 177                                                f: F)
 178                                                -> A
 179         where F: FnOnce(&HirPrinterSupport, B, &hir::Crate) -> A
 180     {
 181         match *self {
 182             PpmNormal => {
 183                 let annotation = NoAnn {
 184                     sess: sess,
 185                     ast_map: Some(ast_map.clone()),
 186                 };
 187                 f(&annotation, payload, ast_map.forest.krate())
 188             }
 189
 190             PpmIdentified => {
 191                 let annotation = IdentifiedAnnotation {
 192                     sess: sess,
 193                     ast_map: Some(ast_map.clone()),
 194                 };
 195                 f(&annotation, payload, ast_map.forest.krate())
 196             }
 197             PpmTyped => {
 198                 abort_on_err(driver::phase_3_run_analysis_passes(sess,
 199                                                                  cstore,
 200                                                                  ast_map.clone(),
 201                                                                  arenas,
 202                                                                  id,
 203                                                                  resolve::MakeGlobMap::No,
 204                                                                  |tcx, _, _, _| {
 205                     let annotation = TypedAnnotation {
 206                         tcx: tcx,
 207                     };
 208                     let _ignore = tcx.dep_graph.in_ignore();
 209                     f(&annotation,
 210                       payload,
 211                       ast_map.forest.krate())
 212                 }), sess)
 213             }
 214             _ => panic!("Should use call_with_pp_support"),
 215         }
 216     }
 217 }
 218
 219 trait PrinterSupport<'ast>: pprust::PpAnn {
 220     /// Provides a uniform interface for re-extracting a reference to a
 221     /// `Session` from a value that now owns it.
 222     fn sess<'a>(&'a self) -> &'a Session;
 223
 224     /// Provides a uniform interface for re-extracting a reference to an
 225     /// `hir_map::Map` from a value that now owns it.
 226     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>>;
 227
 228     /// Produces the pretty-print annotation object.
 229     ///
 230     /// (Rust does not yet support upcasting from a trait object to
 231     /// an object for one of its super-traits.)
 232     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn;
 233 }
 234
 235 trait HirPrinterSupport<'ast>: pprust_hir::PpAnn {
 236     /// Provides a uniform interface for re-extracting a reference to a
 237     /// `Session` from a value that now owns it.
 238     fn sess<'a>(&'a self) -> &'a Session;
 239
 240     /// Provides a uniform interface for re-extracting a reference to an
 241     /// `hir_map::Map` from a value that now owns it.
 242     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>>;
 243
 244     /// Produces the pretty-print annotation object.
 245     ///
 246     /// (Rust does not yet support upcasting from a trait object to
 247     /// an object for one of its super-traits.)
 248     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn;
 249 }
 250
 251 struct NoAnn<'ast> {
 252     sess: &'ast Session,
 253     ast_map: Option<hir_map::Map<'ast>>,
 254 }
 255
 256 impl<'ast> PrinterSupport<'ast> for NoAnn<'ast> {
 257     fn sess<'a>(&'a self) -> &'a Session {
 258         self.sess
 259     }
 260
 261     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 262         self.ast_map.as_ref()
 263     }
 264
 265     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn {
 266         self
 267     }
 268 }
 269
 270 impl<'ast> HirPrinterSupport<'ast> for NoAnn<'ast> {
 271     fn sess<'a>(&'a self) -> &'a Session {
 272         self.sess
 273     }
 274
 275     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 276         self.ast_map.as_ref()
 277     }
 278
 279     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn {
 280         self
 281     }
 282 }
 283
 284 impl<'ast> pprust::PpAnn for NoAnn<'ast> {}
 285 impl<'ast> pprust_hir::PpAnn for NoAnn<'ast> {}
 286
 287 struct IdentifiedAnnotation<'ast> {
 288     sess: &'ast Session,
 289     ast_map: Option<hir_map::Map<'ast>>,
 290 }
 291
 292 impl<'ast> PrinterSupport<'ast> for IdentifiedAnnotation<'ast> {
 293     fn sess<'a>(&'a self) -> &'a Session {
 294         self.sess
 295     }
 296
 297     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 298         self.ast_map.as_ref()
 299     }
 300
 301     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn {
 302         self
 303     }
 304 }
 305
 306 impl<'ast> pprust::PpAnn for IdentifiedAnnotation<'ast> {
 307     fn pre(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 308         match node {
 309             pprust::NodeExpr(_) => s.popen(),
 310             _ => Ok(()),
 311         }
 312     }
 313     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 314         match node {
 315             pprust::NodeIdent(_) | pprust::NodeName(_) => Ok(()),
 316
 317             pprust::NodeItem(item) => {
 318                 try!(pp::space(&mut s.s));
 319                 s.synth_comment(item.id.to_string())
 320             }
 321             pprust::NodeSubItem(id) => {
 322                 try!(pp::space(&mut s.s));
 323                 s.synth_comment(id.to_string())
 324             }
 325             pprust::NodeBlock(blk) => {
 326                 try!(pp::space(&mut s.s));
 327                 s.synth_comment(format!("block {}", blk.id))
 328             }
 329             pprust::NodeExpr(expr) => {
 330                 try!(pp::space(&mut s.s));
 331                 try!(s.synth_comment(expr.id.to_string()));
 332                 s.pclose()
 333             }
 334             pprust::NodePat(pat) => {
 335                 try!(pp::space(&mut s.s));
 336                 s.synth_comment(format!("pat {}", pat.id))
 337             }
 338         }
 339     }
 340 }
 341
 342 impl<'ast> HirPrinterSupport<'ast> for IdentifiedAnnotation<'ast> {
 343     fn sess<'a>(&'a self) -> &'a Session {
 344         self.sess
 345     }
 346
 347     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 348         self.ast_map.as_ref()
 349     }
 350
 351     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn {
 352         self
 353     }
 354 }
 355
 356 impl<'ast> pprust_hir::PpAnn for IdentifiedAnnotation<'ast> {
 357     fn pre(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 358         match node {
 359             pprust_hir::NodeExpr(_) => s.popen(),
 360             _ => Ok(()),
 361         }
 362     }
 363     fn post(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 364         match node {
 365             pprust_hir::NodeName(_) => Ok(()),
 366             pprust_hir::NodeItem(item) => {
 367                 try!(pp::space(&mut s.s));
 368                 s.synth_comment(item.id.to_string())
 369             }
 370             pprust_hir::NodeSubItem(id) => {
 371                 try!(pp::space(&mut s.s));
 372                 s.synth_comment(id.to_string())
 373             }
 374             pprust_hir::NodeBlock(blk) => {
 375                 try!(pp::space(&mut s.s));
 376                 s.synth_comment(format!("block {}", blk.id))
 377             }
 378             pprust_hir::NodeExpr(expr) => {
 379                 try!(pp::space(&mut s.s));
 380                 try!(s.synth_comment(expr.id.to_string()));
 381                 s.pclose()
 382             }
 383             pprust_hir::NodePat(pat) => {
 384                 try!(pp::space(&mut s.s));
 385                 s.synth_comment(format!("pat {}", pat.id))
 386             }
 387         }
 388     }
 389 }
 390
 391 struct HygieneAnnotation<'ast> {
 392     sess: &'ast Session,
 393     ast_map: Option<hir_map::Map<'ast>>,
 394 }
 395
 396 impl<'ast> PrinterSupport<'ast> for HygieneAnnotation<'ast> {
 397     fn sess<'a>(&'a self) -> &'a Session {
 398         self.sess
 399     }
 400
 401     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'ast>> {
 402         self.ast_map.as_ref()
 403     }
 404
 405     fn pp_ann<'a>(&'a self) -> &'a pprust::PpAnn {
 406         self
 407     }
 408 }
 409
 410 impl<'ast> pprust::PpAnn for HygieneAnnotation<'ast> {
 411     fn post(&self, s: &mut pprust::State, node: pprust::AnnNode) -> io::Result<()> {
 412         match node {
 413             pprust::NodeIdent(&ast::Ident { name: ast::Name(nm), ctxt }) => {
 414                 try!(pp::space(&mut s.s));
 415                 // FIXME #16420: this doesn't display the connections
 416                 // between syntax contexts
 417                 s.synth_comment(format!("{}#{}", nm, ctxt.0))
 418             }
 419             pprust::NodeName(&ast::Name(nm)) => {
 420                 try!(pp::space(&mut s.s));
 421                 s.synth_comment(nm.to_string())
 422             }
 423             _ => Ok(()),
 424         }
 425     }
 426 }
 427
 428
 429 struct TypedAnnotation<'a, 'tcx: 'a> {
 430     tcx: &'a ty::ctxt<'tcx>,
 431 }
 432
 433 impl<'b, 'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'b, 'tcx> {
 434     fn sess<'a>(&'a self) -> &'a Session {
 435         &self.tcx.sess
 436     }
 437
 438     fn ast_map<'a>(&'a self) -> Option<&'a hir_map::Map<'tcx>> {
 439         Some(&self.tcx.map)
 440     }
 441
 442     fn pp_ann<'a>(&'a self) -> &'a pprust_hir::PpAnn {
 443         self
 444     }
 445 }
 446
 447 impl<'a, 'tcx> pprust_hir::PpAnn for TypedAnnotation<'a, 'tcx> {
 448     fn pre(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 449         match node {
 450             pprust_hir::NodeExpr(_) => s.popen(),
 451             _ => Ok(()),
 452         }
 453     }
 454     fn post(&self, s: &mut pprust_hir::State, node: pprust_hir::AnnNode) -> io::Result<()> {
 455         match node {
 456             pprust_hir::NodeExpr(expr) => {
 457                 try!(pp::space(&mut s.s));
 458                 try!(pp::word(&mut s.s, "as"));
 459                 try!(pp::space(&mut s.s));
 460                 try!(pp::word(&mut s.s, &self.tcx.expr_ty(expr).to_string()));
 461                 s.pclose()
 462             }
 463             _ => Ok(()),
 464         }
 465     }
 466 }
 467
 468 fn gather_flowgraph_variants(sess: &Session) -> Vec<borrowck_dot::Variant> {
 469     let print_loans = sess.opts.debugging_opts.flowgraph_print_loans;
 470     let print_moves = sess.opts.debugging_opts.flowgraph_print_moves;
 471     let print_assigns = sess.opts.debugging_opts.flowgraph_print_assigns;
 472     let print_all = sess.opts.debugging_opts.flowgraph_print_all;
 473     let mut variants = Vec::new();
 474     if print_all || print_loans {
 475         variants.push(borrowck_dot::Loans);
 476     }
 477     if print_all || print_moves {
 478         variants.push(borrowck_dot::Moves);
 479     }
 480     if print_all || print_assigns {
 481         variants.push(borrowck_dot::Assigns);
 482     }
 483     variants
 484 }
 485
 486 #[derive(Clone, Debug)]
 487 pub enum UserIdentifiedItem {
 488     ItemViaNode(ast::NodeId),
 489     ItemViaPath(Vec<String>),
 490 }
 491
 492 impl FromStr for UserIdentifiedItem {
 493     type Err = ();
 494     fn from_str(s: &str) -> Result<UserIdentifiedItem, ()> {
 495         Ok(s.parse()
 496             .map(ItemViaNode)
 497             .unwrap_or_else(|_| ItemViaPath(s.split("::").map(|s| s.to_string()).collect())))
 498     }
 499 }
 500
 501 enum NodesMatchingUII<'a, 'ast: 'a> {
 502     NodesMatchingDirect(option::IntoIter<ast::NodeId>),
 503     NodesMatchingSuffix(hir_map::NodesMatchingSuffix<'a, 'ast>),
 504 }
 505
 506 impl<'a, 'ast> Iterator for NodesMatchingUII<'a, 'ast> {
 507     type Item = ast::NodeId;
 508
 509     fn next(&mut self) -> Option<ast::NodeId> {
 510         match self {
 511             &mut NodesMatchingDirect(ref mut iter) => iter.next(),
 512             &mut NodesMatchingSuffix(ref mut iter) => iter.next(),
 513         }
 514     }
 515 }
 516
 517 impl UserIdentifiedItem {
 518     fn reconstructed_input(&self) -> String {
 519         match *self {
 520             ItemViaNode(node_id) => node_id.to_string(),
 521             ItemViaPath(ref parts) => parts.join("::"),
 522         }
 523     }
 524
 525     fn all_matching_node_ids<'a, 'ast>(&'a self,
 526                                        map: &'a hir_map::Map<'ast>)
 527                                        -> NodesMatchingUII<'a, 'ast> {
 528         match *self {
 529             ItemViaNode(node_id) => NodesMatchingDirect(Some(node_id).into_iter()),
 530             ItemViaPath(ref parts) => NodesMatchingSuffix(map.nodes_matching_suffix(&parts[..])),
 531         }
 532     }
 533
 534     fn to_one_node_id(self, user_option: &str, sess: &Session, map: &hir_map::Map) -> ast::NodeId {
 535         let fail_because = |is_wrong_because| -> ast::NodeId {
 536             let message = format!("{} needs NodeId (int) or unique path suffix (b::c::d); got \
 537                                    {}, which {}",
 538                                   user_option,
 539                                   self.reconstructed_input(),
 540                                   is_wrong_because);
 541             sess.fatal(&message[..])
 542         };
 543
 544         let mut saw_node = ast::DUMMY_NODE_ID;
 545         let mut seen = 0;
 546         for node in self.all_matching_node_ids(map) {
 547             saw_node = node;
 548             seen += 1;
 549             if seen > 1 {
 550                 fail_because("does not resolve uniquely");
 551             }
 552         }
 553         if seen == 0 {
 554             fail_because("does not resolve to any item");
 555         }
 556
 557         assert!(seen == 1);
 558         return saw_node;
 559     }
 560 }
 561
 562 fn needs_ast_map(ppm: &PpMode, opt_uii: &Option<UserIdentifiedItem>) -> bool {
 563     match *ppm {
 564         PpmSource(PpmNormal) |
 565         PpmSource(PpmEveryBodyLoops) |
 566         PpmSource(PpmIdentified) => opt_uii.is_some(),
 567
 568         PpmSource(PpmExpanded) |
 569         PpmSource(PpmExpandedIdentified) |
 570         PpmSource(PpmExpandedHygiene) |
 571         PpmHir(_) |
 572         PpmFlowGraph(_) => true,
 573         PpmSource(PpmTyped) => panic!("invalid state"),
 574     }
 575 }
 576
 577 fn needs_expansion(ppm: &PpMode) -> bool {
 578     match *ppm {
 579         PpmSource(PpmNormal) |
 580         PpmSource(PpmEveryBodyLoops) |
 581         PpmSource(PpmIdentified) => false,
 582
 583         PpmSource(PpmExpanded) |
 584         PpmSource(PpmExpandedIdentified) |
 585         PpmSource(PpmExpandedHygiene) |
 586         PpmHir(_) |
 587         PpmFlowGraph(_) => true,
 588         PpmSource(PpmTyped) => panic!("invalid state"),
 589     }
 590 }
 591
 592 struct ReplaceBodyWithLoop {
 593     within_static_or_const: bool,
 594 }
 595
 596 impl ReplaceBodyWithLoop {
 597     fn new() -> ReplaceBodyWithLoop {
 598         ReplaceBodyWithLoop { within_static_or_const: false }
 599     }
 600 }
 601
 602 impl fold::Folder for ReplaceBodyWithLoop {
 603     fn fold_item_kind(&mut self, i: ast::ItemKind) -> ast::ItemKind {
 604         match i {
 605             ast::ItemKind::Static(..) | ast::ItemKind::Const(..) => {
 606                 self.within_static_or_const = true;
 607                 let ret = fold::noop_fold_item_kind(i, self);
 608                 self.within_static_or_const = false;
 609                 return ret;
 610             }
 611             _ => {
 612                 fold::noop_fold_item_kind(i, self)
 613             }
 614         }
 615     }
 616
 617     fn fold_trait_item(&mut self, i: ast::TraitItem) -> SmallVector<ast::TraitItem> {
 618         match i.node {
 619             ast::TraitItemKind::Const(..) => {
 620                 self.within_static_or_const = true;
 621                 let ret = fold::noop_fold_trait_item(i, self);
 622                 self.within_static_or_const = false;
 623                 return ret;
 624             }
 625             _ => fold::noop_fold_trait_item(i, self),
 626         }
 627     }
 628
 629     fn fold_impl_item(&mut self, i: ast::ImplItem) -> SmallVector<ast::ImplItem> {
 630         match i.node {
 631             ast::ImplItemKind::Const(..) => {
 632                 self.within_static_or_const = true;
 633                 let ret = fold::noop_fold_impl_item(i, self);
 634                 self.within_static_or_const = false;
 635                 return ret;
 636             }
 637             _ => fold::noop_fold_impl_item(i, self),
 638         }
 639     }
 640
 641     fn fold_block(&mut self, b: P<ast::Block>) -> P<ast::Block> {
 642         fn expr_to_block(rules: ast::BlockCheckMode, e: Option<P<ast::Expr>>) -> P<ast::Block> {
 643             P(ast::Block {
 644                 expr: e,
 645                 stmts: vec![],
 646                 rules: rules,
 647                 id: ast::DUMMY_NODE_ID,
 648                 span: codemap::DUMMY_SP,
 649             })
 650         }
 651
 652         if !self.within_static_or_const {
 653
 654             let empty_block = expr_to_block(BlockCheckMode::Default, None);
 655             let loop_expr = P(ast::Expr {
 656                 node: ast::ExprKind::Loop(empty_block, None),
 657                 id: ast::DUMMY_NODE_ID,
 658                 span: codemap::DUMMY_SP,
 659                 attrs: None,
 660             });
 661
 662             expr_to_block(b.rules, Some(loop_expr))
 663
 664         } else {
 665             fold::noop_fold_block(b, self)
 666         }
 667     }
 668
 669     // in general the pretty printer processes unexpanded code, so
 670     // we override the default `fold_mac` method which panics.
 671     fn fold_mac(&mut self, mac: ast::Mac) -> ast::Mac {
 672         fold::noop_fold_mac(mac, self)
 673     }
 674 }
 675
 676 pub fn pretty_print_input(sess: Session,
 677                           cstore: &CStore,
 678                           cfg: ast::CrateConfig,
 679                           input: &Input,
 680                           ppm: PpMode,
 681                           opt_uii: Option<UserIdentifiedItem>,
 682                           ofile: Option<PathBuf>) {
 683     let krate = driver::phase_1_parse_input(&sess, cfg, input);
 684
 685     let krate = if let PpmSource(PpmEveryBodyLoops) = ppm {
 686         let mut fold = ReplaceBodyWithLoop::new();
 687         fold.fold_crate(krate)
 688     } else {
 689         krate
 690     };
 691
 692     let id = link::find_crate_name(Some(&sess), &krate.attrs, input);
 693
 694     let is_expanded = needs_expansion(&ppm);
 695     let compute_ast_map = needs_ast_map(&ppm, &opt_uii);
 696     let krate = if compute_ast_map {
 697         match driver::phase_2_configure_and_expand(&sess, &cstore, krate, &id[..], None) {
 698             Err(_) => return,
 699             Ok(k) => driver::assign_node_ids(&sess, k),
 700         }
 701     } else {
 702         krate
 703     };
 704
 705     // There is some twisted, god-forsaken tangle of lifetimes here which makes
 706     // the ordering of stuff super-finicky.
 707     let mut hir_forest;
 708     let lcx = LoweringContext::new(&sess, Some(&krate));
 709     let arenas = ty::CtxtArenas::new();
 710     let dep_graph = DepGraph::new(false);
 711     let _ignore = dep_graph.in_ignore();
 712     let ast_map = if compute_ast_map {
 713         hir_forest = hir_map::Forest::new(lower_crate(&lcx, &krate), dep_graph.clone());
 714         let map = driver::make_map(&sess, &mut hir_forest);
 715         Some(map)
 716     } else {
 717         None
 718     };
 719
 720     let src_name = driver::source_name(input);
 721     let src = sess.codemap()
 722                   .get_filemap(&src_name[..])
 723                   .src
 724                   .as_ref()
 725                   .unwrap()
 726                   .as_bytes()
 727                   .to_vec();
 728     let mut rdr = &src[..];
 729
 730     let mut out = Vec::new();
 731
 732     match (ppm, opt_uii) {
 733         (PpmSource(s), _) => {
 734             // Silently ignores an identified node.
 735             let out: &mut Write = &mut out;
 736             s.call_with_pp_support(&sess, ast_map, box out, |annotation, out| {
 737                 debug!("pretty printing source code {:?}", s);
 738                 let sess = annotation.sess();
 739                 pprust::print_crate(sess.codemap(),
 740                                     sess.diagnostic(),
 741                                     &krate,
 742                                     src_name.to_string(),
 743                                     &mut rdr,
 744                                     out,
 745                                     annotation.pp_ann(),
 746                                     is_expanded)
 747             })
 748         }
 749
 750         (PpmHir(s), None) => {
 751             let out: &mut Write = &mut out;
 752             s.call_with_pp_support_hir(&sess,
 753                                        cstore,
 754                                        &ast_map.unwrap(),
 755                                        &arenas,
 756                                        &id,
 757                                        box out,
 758                                        |annotation, out, krate| {
 759                                            debug!("pretty printing source code {:?}", s);
 760                                            let sess = annotation.sess();
 761                                            pprust_hir::print_crate(sess.codemap(),
 762                                                                    sess.diagnostic(),
 763                                                                    krate,
 764                                                                    src_name.to_string(),
 765                                                                    &mut rdr,
 766                                                                    out,
 767                                                                    annotation.pp_ann(),
 768                                                                    is_expanded)
 769                                        })
 770         }
 771
 772         (PpmHir(s), Some(uii)) => {
 773             let out: &mut Write = &mut out;
 774             s.call_with_pp_support_hir(&sess,
 775                                        cstore,
 776                                        &ast_map.unwrap(),
 777                                        &arenas,
 778                                        &id,
 779                                        (out,uii),
 780                                        |annotation, (out,uii), _| {
 781                 debug!("pretty printing source code {:?}", s);
 782                 let sess = annotation.sess();
 783                 let ast_map = annotation.ast_map().expect("--pretty missing ast_map");
 784                 let mut pp_state =
 785                     pprust_hir::State::new_from_input(sess.codemap(),
 786                                                       sess.diagnostic(),
 787                                                       src_name.to_string(),
 788                                                       &mut rdr,
 789                                                       box out,
 790                                                       annotation.pp_ann(),
 791                                                       true,
 792                                                       Some(ast_map.krate()));
 793                 for node_id in uii.all_matching_node_ids(ast_map) {
 794                     let node = ast_map.get(node_id);
 795                     try!(pp_state.print_node(&node));
 796                     try!(pp::space(&mut pp_state.s));
 797                     try!(pp_state.synth_comment(ast_map.path_to_string(node_id)));
 798                     try!(pp::hardbreak(&mut pp_state.s));
 799                 }
 800                 pp::eof(&mut pp_state.s)
 801             })
 802         }
 803
 804         (PpmFlowGraph(mode), opt_uii) => {
 805             debug!("pretty printing flow graph for {:?}", opt_uii);
 806             let uii = opt_uii.unwrap_or_else(|| {
 807                 sess.fatal(&format!("`pretty flowgraph=..` needs NodeId (int) or
 808                                      \
 809                                      unique path suffix (b::c::d)"))
 810
 811             });
 812             let ast_map = ast_map.expect("--pretty flowgraph missing ast_map");
 813             let nodeid = uii.to_one_node_id("--pretty", &sess, &ast_map);
 814
 815             let node = ast_map.find(nodeid).unwrap_or_else(|| {
 816                 sess.fatal(&format!("--pretty flowgraph couldn't find id: {}", nodeid))
 817             });
 818
 819             let code = blocks::Code::from_node(node);
 820             let out: &mut Write = &mut out;
 821             match code {
 822                 Some(code) => {
 823                     let variants = gather_flowgraph_variants(&sess);
 824                     abort_on_err(driver::phase_3_run_analysis_passes(&sess,
 825                                                                      &cstore,
 826                                                                      ast_map,
 827                                                                      &arenas,
 828                                                                      &id,
 829                                                                      resolve::MakeGlobMap::No,
 830                                                                      |tcx, _, _, _| {
 831                         print_flowgraph(variants,
 832                                         tcx,
 833                                         code,
 834                                         mode,
 835                                         out)
 836                     }), &sess)
 837                 }
 838                 None => {
 839                     let message = format!("--pretty=flowgraph needs block, fn, or method; got \
 840                                            {:?}",
 841                                           node);
 842
 843                     // point to what was found, if there's an
 844                     // accessible span.
 845                     match ast_map.opt_span(nodeid) {
 846                         Some(sp) => sess.span_fatal(sp, &message[..]),
 847                         None => sess.fatal(&message[..]),
 848                     }
 849                 }
 850             }
 851         }
 852     }
 853     .unwrap();
 854
 855     match ofile {
 856         None => print!("{}", String::from_utf8(out).unwrap()),
 857         Some(p) => {
 858             match File::create(&p) {
 859                 Ok(mut w) => w.write_all(&out).unwrap(),
 860                 Err(e) => panic!("print-print failed to open {} due to {}", p.display(), e),
 861             }
 862         }
 863     }
 864 }
 865
 866 fn print_flowgraph<W: Write>(variants: Vec<borrowck_dot::Variant>,
 867                              tcx: &ty::ctxt,
 868                              code: blocks::Code,
 869                              mode: PpFlowGraphMode,
 870                              mut out: W)
 871                              -> io::Result<()> {
 872     let cfg = match code {
 873         blocks::BlockCode(block) => cfg::CFG::new(tcx, &block),
 874         blocks::FnLikeCode(fn_like) => cfg::CFG::new(tcx, &fn_like.body()),
 875     };
 876     let labelled_edges = mode != PpFlowGraphMode::UnlabelledEdges;
 877     let lcfg = LabelledCFG {
 878         ast_map: &tcx.map,
 879         cfg: &cfg,
 880         name: format!("node_{}", code.id()),
 881         labelled_edges: labelled_edges,
 882     };
 883
 884     match code {
 885         _ if variants.is_empty() => {
 886             let r = dot::render(&lcfg, &mut out);
 887             return expand_err_details(r);
 888         }
 889         blocks::BlockCode(_) => {
 890             tcx.sess.err("--pretty flowgraph with -Z flowgraph-print annotations requires \
 891                           fn-like node id.");
 892             return Ok(());
 893         }
 894         blocks::FnLikeCode(fn_like) => {
 895             let (bccx, analysis_data) =
 896                 borrowck::build_borrowck_dataflow_data_for_fn(tcx,
 897                                                               fn_like.to_fn_parts(),
 898                                                               &cfg);
 899
 900             let lcfg = borrowck_dot::DataflowLabeller {
 901                 inner: lcfg,
 902                 variants: variants,
 903                 borrowck_ctxt: &bccx,
 904                 analysis_data: &analysis_data,
 905             };
 906             let r = dot::render(&lcfg, &mut out);
 907             return expand_err_details(r);
 908         }
 909     }
 910
 911     fn expand_err_details(r: io::Result<()>) -> io::Result<()> {
 912         r.map_err(|ioerr| {
 913             io::Error::new(io::ErrorKind::Other,
 914                            &format!("graphviz::render failed: {}", ioerr)[..])
 915         })
 916     }
 917 }