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