src/librustc_driver/pretty.rs

   1 //! The various pretty-printing routines.
   2
   3 use rustc_ast::ast;
   4 use rustc_ast_pretty::pprust;
   5 use rustc_errors::ErrorReported;
   6 use rustc_hir as hir;
   7 use rustc_hir::def_id::LOCAL_CRATE;
   8 use rustc_hir_pretty as pprust_hir;
   9 use rustc_middle::hir::map as hir_map;
  10 use rustc_middle::ty::{self, TyCtxt};
  11 use rustc_mir::util::{write_mir_graphviz, write_mir_pretty};
  12 use rustc_session::config::{Input, PpMode, PpSourceMode};
  13 use rustc_session::Session;
  14 use rustc_span::FileName;
  15
  16 use std::cell::Cell;
  17 use std::fs::File;
  18 use std::io::Write;
  19 use std::path::Path;
  20
  21 pub use self::PpMode::*;
  22 pub use self::PpSourceMode::*;
  23 use crate::abort_on_err;
  24
  25 // This slightly awkward construction is to allow for each PpMode to
  26 // choose whether it needs to do analyses (which can consume the
  27 // Session) and then pass through the session (now attached to the
  28 // analysis results) on to the chosen pretty-printer, along with the
  29 // `&PpAnn` object.
  30 //
  31 // Note that since the `&PrinterSupport` is freshly constructed on each
  32 // call, it would not make sense to try to attach the lifetime of `self`
  33 // to the lifetime of the `&PrinterObject`.
  34 //
  35 // (The `use_once_payload` is working around the current lack of once
  36 // functions in the compiler.)
  37
  38 /// Constructs a `PrinterSupport` object and passes it to `f`.
  39 fn call_with_pp_support<'tcx, A, F>(
  40     ppmode: &PpSourceMode,
  41     sess: &'tcx Session,
  42     tcx: Option<TyCtxt<'tcx>>,
  43     f: F,
  44 ) -> A
  45 where
  46     F: FnOnce(&dyn PrinterSupport) -> A,
  47 {
  48     match *ppmode {
  49         PpmNormal | PpmEveryBodyLoops | PpmExpanded => {
  50             let annotation = NoAnn { sess, tcx };
  51             f(&annotation)
  52         }
  53
  54         PpmIdentified | PpmExpandedIdentified => {
  55             let annotation = IdentifiedAnnotation { sess, tcx };
  56             f(&annotation)
  57         }
  58         PpmExpandedHygiene => {
  59             let annotation = HygieneAnnotation { sess };
  60             f(&annotation)
  61         }
  62         _ => panic!("Should use call_with_pp_support_hir"),
  63     }
  64 }
  65 fn call_with_pp_support_hir<A, F>(ppmode: &PpSourceMode, tcx: TyCtxt<'_>, f: F) -> A
  66 where
  67     F: FnOnce(&dyn HirPrinterSupport<'_>, &hir::Crate<'_>) -> A,
  68 {
  69     match *ppmode {
  70         PpmNormal => {
  71             let annotation = NoAnn { sess: tcx.sess, tcx: Some(tcx) };
  72             f(&annotation, tcx.hir().krate())
  73         }
  74
  75         PpmIdentified => {
  76             let annotation = IdentifiedAnnotation { sess: tcx.sess, tcx: Some(tcx) };
  77             f(&annotation, tcx.hir().krate())
  78         }
  79         PpmTyped => {
  80             abort_on_err(tcx.analysis(LOCAL_CRATE), tcx.sess);
  81
  82             let empty_tables = ty::TypeckTables::empty(None);
  83             let annotation = TypedAnnotation { tcx, tables: Cell::new(&empty_tables) };
  84             tcx.dep_graph.with_ignore(|| f(&annotation, tcx.hir().krate()))
  85         }
  86         _ => panic!("Should use call_with_pp_support"),
  87     }
  88 }
  89
  90 trait PrinterSupport: pprust::PpAnn {
  91     /// Provides a uniform interface for re-extracting a reference to a
  92     /// `Session` from a value that now owns it.
  93     fn sess(&self) -> &Session;
  94
  95     /// Produces the pretty-print annotation object.
  96     ///
  97     /// (Rust does not yet support upcasting from a trait object to
  98     /// an object for one of its super-traits.)
  99     fn pp_ann(&self) -> &dyn pprust::PpAnn;
 100 }
 101
 102 trait HirPrinterSupport<'hir>: pprust_hir::PpAnn {
 103     /// Provides a uniform interface for re-extracting a reference to a
 104     /// `Session` from a value that now owns it.
 105     fn sess(&self) -> &Session;
 106
 107     /// Provides a uniform interface for re-extracting a reference to an
 108     /// `hir_map::Map` from a value that now owns it.
 109     fn hir_map(&self) -> Option<hir_map::Map<'hir>>;
 110
 111     /// Produces the pretty-print annotation object.
 112     ///
 113     /// (Rust does not yet support upcasting from a trait object to
 114     /// an object for one of its super-traits.)
 115     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn;
 116
 117     /// Computes an user-readable representation of a path, if possible.
 118     fn node_path(&self, id: hir::HirId) -> Option<String> {
 119         self.hir_map().and_then(|map| map.def_path_from_hir_id(id)).map(|path| {
 120             path.data.into_iter().map(|elem| elem.data.to_string()).collect::<Vec<_>>().join("::")
 121         })
 122     }
 123 }
 124
 125 struct NoAnn<'hir> {
 126     sess: &'hir Session,
 127     tcx: Option<TyCtxt<'hir>>,
 128 }
 129
 130 impl<'hir> PrinterSupport for NoAnn<'hir> {
 131     fn sess(&self) -> &Session {
 132         self.sess
 133     }
 134
 135     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 136         self
 137     }
 138 }
 139
 140 impl<'hir> HirPrinterSupport<'hir> for NoAnn<'hir> {
 141     fn sess(&self) -> &Session {
 142         self.sess
 143     }
 144
 145     fn hir_map(&self) -> Option<hir_map::Map<'hir>> {
 146         self.tcx.map(|tcx| tcx.hir())
 147     }
 148
 149     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 150         self
 151     }
 152 }
 153
 154 impl<'hir> pprust::PpAnn for NoAnn<'hir> {}
 155 impl<'hir> pprust_hir::PpAnn for NoAnn<'hir> {
 156     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 157         if let Some(tcx) = self.tcx {
 158             pprust_hir::PpAnn::nested(&(&tcx.hir() as &dyn hir::intravisit::Map<'_>), state, nested)
 159         }
 160     }
 161 }
 162
 163 struct IdentifiedAnnotation<'hir> {
 164     sess: &'hir Session,
 165     tcx: Option<TyCtxt<'hir>>,
 166 }
 167
 168 impl<'hir> PrinterSupport for IdentifiedAnnotation<'hir> {
 169     fn sess(&self) -> &Session {
 170         self.sess
 171     }
 172
 173     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 174         self
 175     }
 176 }
 177
 178 impl<'hir> pprust::PpAnn for IdentifiedAnnotation<'hir> {
 179     fn pre(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 180         if let pprust::AnnNode::Expr(_) = node {
 181             s.popen();
 182         }
 183     }
 184     fn post(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 185         match node {
 186             pprust::AnnNode::Crate(_) | pprust::AnnNode::Ident(_) | pprust::AnnNode::Name(_) => {}
 187
 188             pprust::AnnNode::Item(item) => {
 189                 s.s.space();
 190                 s.synth_comment(item.id.to_string())
 191             }
 192             pprust::AnnNode::SubItem(id) => {
 193                 s.s.space();
 194                 s.synth_comment(id.to_string())
 195             }
 196             pprust::AnnNode::Block(blk) => {
 197                 s.s.space();
 198                 s.synth_comment(format!("block {}", blk.id))
 199             }
 200             pprust::AnnNode::Expr(expr) => {
 201                 s.s.space();
 202                 s.synth_comment(expr.id.to_string());
 203                 s.pclose()
 204             }
 205             pprust::AnnNode::Pat(pat) => {
 206                 s.s.space();
 207                 s.synth_comment(format!("pat {}", pat.id));
 208             }
 209         }
 210     }
 211 }
 212
 213 impl<'hir> HirPrinterSupport<'hir> for IdentifiedAnnotation<'hir> {
 214     fn sess(&self) -> &Session {
 215         self.sess
 216     }
 217
 218     fn hir_map(&self) -> Option<hir_map::Map<'hir>> {
 219         self.tcx.map(|tcx| tcx.hir())
 220     }
 221
 222     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 223         self
 224     }
 225 }
 226
 227 impl<'hir> pprust_hir::PpAnn for IdentifiedAnnotation<'hir> {
 228     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 229         if let Some(ref tcx) = self.tcx {
 230             pprust_hir::PpAnn::nested(&(&tcx.hir() as &dyn hir::intravisit::Map<'_>), state, nested)
 231         }
 232     }
 233     fn pre(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 234         if let pprust_hir::AnnNode::Expr(_) = node {
 235             s.popen();
 236         }
 237     }
 238     fn post(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 239         match node {
 240             pprust_hir::AnnNode::Name(_) => {}
 241             pprust_hir::AnnNode::Item(item) => {
 242                 s.s.space();
 243                 s.synth_comment(format!("hir_id: {}", item.hir_id));
 244             }
 245             pprust_hir::AnnNode::SubItem(id) => {
 246                 s.s.space();
 247                 s.synth_comment(id.to_string());
 248             }
 249             pprust_hir::AnnNode::Block(blk) => {
 250                 s.s.space();
 251                 s.synth_comment(format!("block hir_id: {}", blk.hir_id));
 252             }
 253             pprust_hir::AnnNode::Expr(expr) => {
 254                 s.s.space();
 255                 s.synth_comment(format!("expr hir_id: {}", expr.hir_id));
 256                 s.pclose();
 257             }
 258             pprust_hir::AnnNode::Pat(pat) => {
 259                 s.s.space();
 260                 s.synth_comment(format!("pat hir_id: {}", pat.hir_id));
 261             }
 262             pprust_hir::AnnNode::Arm(arm) => {
 263                 s.s.space();
 264                 s.synth_comment(format!("arm hir_id: {}", arm.hir_id));
 265             }
 266         }
 267     }
 268 }
 269
 270 struct HygieneAnnotation<'a> {
 271     sess: &'a Session,
 272 }
 273
 274 impl<'a> PrinterSupport for HygieneAnnotation<'a> {
 275     fn sess(&self) -> &Session {
 276         self.sess
 277     }
 278
 279     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 280         self
 281     }
 282 }
 283
 284 impl<'a> pprust::PpAnn for HygieneAnnotation<'a> {
 285     fn post(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 286         match node {
 287             pprust::AnnNode::Ident(&ast::Ident { name, span }) => {
 288                 s.s.space();
 289                 s.synth_comment(format!("{}{:?}", name.as_u32(), span.ctxt()))
 290             }
 291             pprust::AnnNode::Name(&name) => {
 292                 s.s.space();
 293                 s.synth_comment(name.as_u32().to_string())
 294             }
 295             pprust::AnnNode::Crate(_) => {
 296                 s.s.hardbreak();
 297                 let verbose = self.sess.verbose();
 298                 s.synth_comment(rustc_span::hygiene::debug_hygiene_data(verbose));
 299                 s.s.hardbreak_if_not_bol();
 300             }
 301             _ => {}
 302         }
 303     }
 304 }
 305
 306 struct TypedAnnotation<'a, 'tcx> {
 307     tcx: TyCtxt<'tcx>,
 308     tables: Cell<&'a ty::TypeckTables<'tcx>>,
 309 }
 310
 311 impl<'b, 'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'b, 'tcx> {
 312     fn sess(&self) -> &Session {
 313         &self.tcx.sess
 314     }
 315
 316     fn hir_map(&self) -> Option<hir_map::Map<'tcx>> {
 317         Some(self.tcx.hir())
 318     }
 319
 320     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 321         self
 322     }
 323
 324     fn node_path(&self, id: hir::HirId) -> Option<String> {
 325         Some(self.tcx.def_path_str(self.tcx.hir().local_def_id(id)))
 326     }
 327 }
 328
 329 impl<'a, 'tcx> pprust_hir::PpAnn for TypedAnnotation<'a, 'tcx> {
 330     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 331         let old_tables = self.tables.get();
 332         if let pprust_hir::Nested::Body(id) = nested {
 333             self.tables.set(self.tcx.body_tables(id));
 334         }
 335         let pp_ann = &(&self.tcx.hir() as &dyn hir::intravisit::Map<'_>);
 336         pprust_hir::PpAnn::nested(pp_ann, state, nested);
 337         self.tables.set(old_tables);
 338     }
 339     fn pre(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 340         if let pprust_hir::AnnNode::Expr(_) = node {
 341             s.popen();
 342         }
 343     }
 344     fn post(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 345         if let pprust_hir::AnnNode::Expr(expr) = node {
 346             s.s.space();
 347             s.s.word("as");
 348             s.s.space();
 349             s.s.word(self.tables.get().expr_ty(expr).to_string());
 350             s.pclose();
 351         }
 352     }
 353 }
 354
 355 fn get_source(input: &Input, sess: &Session) -> (String, FileName) {
 356     let src_name = input.source_name();
 357     let src =
 358         String::clone(&sess.source_map().get_source_file(&src_name).unwrap().src.as_ref().unwrap());
 359     (src, src_name)
 360 }
 361
 362 fn write_output(out: Vec<u8>, ofile: Option<&Path>) {
 363     match ofile {
 364         None => print!("{}", String::from_utf8(out).unwrap()),
 365         Some(p) => match File::create(p) {
 366             Ok(mut w) => w.write_all(&out).unwrap(),
 367             Err(e) => panic!("print-print failed to open {} due to {}", p.display(), e),
 368         },
 369     }
 370 }
 371
 372 pub fn print_after_parsing(
 373     sess: &Session,
 374     input: &Input,
 375     krate: &ast::Crate,
 376     ppm: PpMode,
 377     ofile: Option<&Path>,
 378 ) {
 379     let (src, src_name) = get_source(input, sess);
 380
 381     let mut out = String::new();
 382
 383     if let PpmSource(s) = ppm {
 384         // Silently ignores an identified node.
 385         let out = &mut out;
 386         call_with_pp_support(&s, sess, None, move |annotation| {
 387             debug!("pretty printing source code {:?}", s);
 388             let sess = annotation.sess();
 389             let parse = &sess.parse_sess;
 390             *out = pprust::print_crate(
 391                 sess.source_map(),
 392                 krate,
 393                 src_name,
 394                 src,
 395                 annotation.pp_ann(),
 396                 false,
 397                 parse.edition,
 398                 parse.injected_crate_name.try_get().is_some(),
 399             )
 400         })
 401     } else {
 402         unreachable!();
 403     };
 404
 405     write_output(out.into_bytes(), ofile);
 406 }
 407
 408 pub fn print_after_hir_lowering<'tcx>(
 409     tcx: TyCtxt<'tcx>,
 410     input: &Input,
 411     krate: &ast::Crate,
 412     ppm: PpMode,
 413     ofile: Option<&Path>,
 414 ) {
 415     if ppm.needs_analysis() {
 416         abort_on_err(print_with_analysis(tcx, ppm, ofile), tcx.sess);
 417         return;
 418     }
 419
 420     let (src, src_name) = get_source(input, tcx.sess);
 421
 422     let mut out = String::new();
 423
 424     match ppm {
 425         PpmSource(s) => {
 426             // Silently ignores an identified node.
 427             let out = &mut out;
 428             call_with_pp_support(&s, tcx.sess, Some(tcx), move |annotation| {
 429                 debug!("pretty printing source code {:?}", s);
 430                 let sess = annotation.sess();
 431                 let parse = &sess.parse_sess;
 432                 *out = pprust::print_crate(
 433                     sess.source_map(),
 434                     krate,
 435                     src_name,
 436                     src,
 437                     annotation.pp_ann(),
 438                     true,
 439                     parse.edition,
 440                     parse.injected_crate_name.try_get().is_some(),
 441                 )
 442             })
 443         }
 444
 445         PpmHir(s) => {
 446             let out = &mut out;
 447             call_with_pp_support_hir(&s, tcx, move |annotation, krate| {
 448                 debug!("pretty printing source code {:?}", s);
 449                 let sess = annotation.sess();
 450                 let sm = sess.source_map();
 451                 *out = pprust_hir::print_crate(sm, krate, src_name, src, annotation.pp_ann())
 452             })
 453         }
 454
 455         PpmHirTree(s) => {
 456             let out = &mut out;
 457             call_with_pp_support_hir(&s, tcx, move |_annotation, krate| {
 458                 debug!("pretty printing source code {:?}", s);
 459                 *out = format!("{:#?}", krate);
 460             });
 461         }
 462
 463         _ => unreachable!(),
 464     }
 465
 466     write_output(out.into_bytes(), ofile);
 467 }
 468
 469 // In an ideal world, this would be a public function called by the driver after
 470 // analysis is performed. However, we want to call `phase_3_run_analysis_passes`
 471 // with a different callback than the standard driver, so that isn't easy.
 472 // Instead, we call that function ourselves.
 473 fn print_with_analysis(
 474     tcx: TyCtxt<'_>,
 475     ppm: PpMode,
 476     ofile: Option<&Path>,
 477 ) -> Result<(), ErrorReported> {
 478     let mut out = Vec::new();
 479
 480     tcx.analysis(LOCAL_CRATE)?;
 481
 482     match ppm {
 483         PpmMir | PpmMirCFG => match ppm {
 484             PpmMir => write_mir_pretty(tcx, None, &mut out),
 485             PpmMirCFG => write_mir_graphviz(tcx, None, &mut out),
 486             _ => unreachable!(),
 487         },
 488         _ => unreachable!(),
 489     }
 490     .unwrap();
 491
 492     write_output(out, ofile);
 493
 494     Ok(())
 495 }