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