compiler/rustc_driver/src/pretty.rs

   1 //! The various pretty-printing routines.
   2
   3 use rustc_ast as 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::symbol::Ident;
  15 use rustc_span::FileName;
  16
  17 use std::cell::Cell;
  18 use std::fs::File;
  19 use std::io::Write;
  20 use std::path::Path;
  21
  22 pub use self::PpMode::*;
  23 pub use self::PpSourceMode::*;
  24 use crate::abort_on_err;
  25
  26 // This slightly awkward construction is to allow for each PpMode to
  27 // choose whether it needs to do analyses (which can consume the
  28 // Session) and then pass through the session (now attached to the
  29 // analysis results) on to the chosen pretty-printer, along with the
  30 // `&PpAnn` object.
  31 //
  32 // Note that since the `&PrinterSupport` is freshly constructed on each
  33 // call, it would not make sense to try to attach the lifetime of `self`
  34 // to the lifetime of the `&PrinterObject`.
  35
  36 /// Constructs a `PrinterSupport` object and passes it to `f`.
  37 fn call_with_pp_support<'tcx, A, F>(
  38     ppmode: &PpSourceMode,
  39     sess: &'tcx Session,
  40     tcx: Option<TyCtxt<'tcx>>,
  41     f: F,
  42 ) -> A
  43 where
  44     F: FnOnce(&dyn PrinterSupport) -> A,
  45 {
  46     match *ppmode {
  47         PpmNormal | PpmEveryBodyLoops | PpmExpanded => {
  48             let annotation = NoAnn { sess, tcx };
  49             f(&annotation)
  50         }
  51
  52         PpmIdentified | PpmExpandedIdentified => {
  53             let annotation = IdentifiedAnnotation { sess, tcx };
  54             f(&annotation)
  55         }
  56         PpmExpandedHygiene => {
  57             let annotation = HygieneAnnotation { sess };
  58             f(&annotation)
  59         }
  60         _ => panic!("Should use call_with_pp_support_hir"),
  61     }
  62 }
  63 fn call_with_pp_support_hir<A, F>(ppmode: &PpSourceMode, tcx: TyCtxt<'_>, f: F) -> A
  64 where
  65     F: FnOnce(&dyn HirPrinterSupport<'_>, &hir::Crate<'_>) -> A,
  66 {
  67     match *ppmode {
  68         PpmNormal => {
  69             let annotation = NoAnn { sess: tcx.sess, tcx: Some(tcx) };
  70             f(&annotation, tcx.hir().krate())
  71         }
  72
  73         PpmIdentified => {
  74             let annotation = IdentifiedAnnotation { sess: tcx.sess, tcx: Some(tcx) };
  75             f(&annotation, tcx.hir().krate())
  76         }
  77         PpmTyped => {
  78             abort_on_err(tcx.analysis(LOCAL_CRATE), tcx.sess);
  79
  80             let annotation = TypedAnnotation { tcx, maybe_typeck_results: Cell::new(None) };
  81             tcx.dep_graph.with_ignore(|| f(&annotation, tcx.hir().krate()))
  82         }
  83         _ => panic!("Should use call_with_pp_support"),
  84     }
  85 }
  86
  87 trait PrinterSupport: pprust::PpAnn {
  88     /// Provides a uniform interface for re-extracting a reference to a
  89     /// `Session` from a value that now owns it.
  90     fn sess(&self) -> &Session;
  91
  92     /// Produces the pretty-print annotation object.
  93     ///
  94     /// (Rust does not yet support upcasting from a trait object to
  95     /// an object for one of its super-traits.)
  96     fn pp_ann(&self) -> &dyn pprust::PpAnn;
  97 }
  98
  99 trait HirPrinterSupport<'hir>: pprust_hir::PpAnn {
 100     /// Provides a uniform interface for re-extracting a reference to a
 101     /// `Session` from a value that now owns it.
 102     fn sess(&self) -> &Session;
 103
 104     /// Provides a uniform interface for re-extracting a reference to an
 105     /// `hir_map::Map` from a value that now owns it.
 106     fn hir_map(&self) -> Option<hir_map::Map<'hir>>;
 107
 108     /// Produces the pretty-print annotation object.
 109     ///
 110     /// (Rust does not yet support upcasting from a trait object to
 111     /// an object for one of its super-traits.)
 112     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn;
 113
 114     /// Computes an user-readable representation of a path, if possible.
 115     fn node_path(&self, id: hir::HirId) -> Option<String> {
 116         self.hir_map().and_then(|map| map.def_path_from_hir_id(id)).map(|path| {
 117             path.data.into_iter().map(|elem| elem.data.to_string()).collect::<Vec<_>>().join("::")
 118         })
 119     }
 120 }
 121
 122 struct NoAnn<'hir> {
 123     sess: &'hir Session,
 124     tcx: Option<TyCtxt<'hir>>,
 125 }
 126
 127 impl<'hir> PrinterSupport for NoAnn<'hir> {
 128     fn sess(&self) -> &Session {
 129         self.sess
 130     }
 131
 132     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 133         self
 134     }
 135 }
 136
 137 impl<'hir> HirPrinterSupport<'hir> for NoAnn<'hir> {
 138     fn sess(&self) -> &Session {
 139         self.sess
 140     }
 141
 142     fn hir_map(&self) -> Option<hir_map::Map<'hir>> {
 143         self.tcx.map(|tcx| tcx.hir())
 144     }
 145
 146     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 147         self
 148     }
 149 }
 150
 151 impl<'hir> pprust::PpAnn for NoAnn<'hir> {}
 152 impl<'hir> pprust_hir::PpAnn for NoAnn<'hir> {
 153     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 154         if let Some(tcx) = self.tcx {
 155             pprust_hir::PpAnn::nested(&(&tcx.hir() as &dyn hir::intravisit::Map<'_>), state, nested)
 156         }
 157     }
 158 }
 159
 160 struct IdentifiedAnnotation<'hir> {
 161     sess: &'hir Session,
 162     tcx: Option<TyCtxt<'hir>>,
 163 }
 164
 165 impl<'hir> PrinterSupport for IdentifiedAnnotation<'hir> {
 166     fn sess(&self) -> &Session {
 167         self.sess
 168     }
 169
 170     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 171         self
 172     }
 173 }
 174
 175 impl<'hir> pprust::PpAnn for IdentifiedAnnotation<'hir> {
 176     fn pre(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 177         if let pprust::AnnNode::Expr(_) = node {
 178             s.popen();
 179         }
 180     }
 181     fn post(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 182         match node {
 183             pprust::AnnNode::Crate(_) | pprust::AnnNode::Ident(_) | pprust::AnnNode::Name(_) => {}
 184
 185             pprust::AnnNode::Item(item) => {
 186                 s.s.space();
 187                 s.synth_comment(item.id.to_string())
 188             }
 189             pprust::AnnNode::SubItem(id) => {
 190                 s.s.space();
 191                 s.synth_comment(id.to_string())
 192             }
 193             pprust::AnnNode::Block(blk) => {
 194                 s.s.space();
 195                 s.synth_comment(format!("block {}", blk.id))
 196             }
 197             pprust::AnnNode::Expr(expr) => {
 198                 s.s.space();
 199                 s.synth_comment(expr.id.to_string());
 200                 s.pclose()
 201             }
 202             pprust::AnnNode::Pat(pat) => {
 203                 s.s.space();
 204                 s.synth_comment(format!("pat {}", pat.id));
 205             }
 206         }
 207     }
 208 }
 209
 210 impl<'hir> HirPrinterSupport<'hir> for IdentifiedAnnotation<'hir> {
 211     fn sess(&self) -> &Session {
 212         self.sess
 213     }
 214
 215     fn hir_map(&self) -> Option<hir_map::Map<'hir>> {
 216         self.tcx.map(|tcx| tcx.hir())
 217     }
 218
 219     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 220         self
 221     }
 222 }
 223
 224 impl<'hir> pprust_hir::PpAnn for IdentifiedAnnotation<'hir> {
 225     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 226         if let Some(ref tcx) = self.tcx {
 227             pprust_hir::PpAnn::nested(&(&tcx.hir() as &dyn hir::intravisit::Map<'_>), state, nested)
 228         }
 229     }
 230     fn pre(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 231         if let pprust_hir::AnnNode::Expr(_) = node {
 232             s.popen();
 233         }
 234     }
 235     fn post(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 236         match node {
 237             pprust_hir::AnnNode::Name(_) => {}
 238             pprust_hir::AnnNode::Item(item) => {
 239                 s.s.space();
 240                 s.synth_comment(format!("hir_id: {}", item.hir_id));
 241             }
 242             pprust_hir::AnnNode::SubItem(id) => {
 243                 s.s.space();
 244                 s.synth_comment(id.to_string());
 245             }
 246             pprust_hir::AnnNode::Block(blk) => {
 247                 s.s.space();
 248                 s.synth_comment(format!("block hir_id: {}", blk.hir_id));
 249             }
 250             pprust_hir::AnnNode::Expr(expr) => {
 251                 s.s.space();
 252                 s.synth_comment(format!("expr hir_id: {}", expr.hir_id));
 253                 s.pclose();
 254             }
 255             pprust_hir::AnnNode::Pat(pat) => {
 256                 s.s.space();
 257                 s.synth_comment(format!("pat hir_id: {}", pat.hir_id));
 258             }
 259             pprust_hir::AnnNode::Arm(arm) => {
 260                 s.s.space();
 261                 s.synth_comment(format!("arm hir_id: {}", arm.hir_id));
 262             }
 263         }
 264     }
 265 }
 266
 267 struct HygieneAnnotation<'a> {
 268     sess: &'a Session,
 269 }
 270
 271 impl<'a> PrinterSupport for HygieneAnnotation<'a> {
 272     fn sess(&self) -> &Session {
 273         self.sess
 274     }
 275
 276     fn pp_ann(&self) -> &dyn pprust::PpAnn {
 277         self
 278     }
 279 }
 280
 281 impl<'a> pprust::PpAnn for HygieneAnnotation<'a> {
 282     fn post(&self, s: &mut pprust::State<'_>, node: pprust::AnnNode<'_>) {
 283         match node {
 284             pprust::AnnNode::Ident(&Ident { name, span }) => {
 285                 s.s.space();
 286                 s.synth_comment(format!("{}{:?}", name.as_u32(), span.ctxt()))
 287             }
 288             pprust::AnnNode::Name(&name) => {
 289                 s.s.space();
 290                 s.synth_comment(name.as_u32().to_string())
 291             }
 292             pprust::AnnNode::Crate(_) => {
 293                 s.s.hardbreak();
 294                 let verbose = self.sess.verbose();
 295                 s.synth_comment(rustc_span::hygiene::debug_hygiene_data(verbose));
 296                 s.s.hardbreak_if_not_bol();
 297             }
 298             _ => {}
 299         }
 300     }
 301 }
 302
 303 struct TypedAnnotation<'tcx> {
 304     tcx: TyCtxt<'tcx>,
 305     maybe_typeck_results: Cell<Option<&'tcx ty::TypeckResults<'tcx>>>,
 306 }
 307
 308 impl<'tcx> TypedAnnotation<'tcx> {
 309     /// Gets the type-checking results for the current body.
 310     /// As this will ICE if called outside bodies, only call when working with
 311     /// `Expr` or `Pat` nodes (they are guaranteed to be found only in bodies).
 312     #[track_caller]
 313     fn typeck_results(&self) -> &'tcx ty::TypeckResults<'tcx> {
 314         self.maybe_typeck_results
 315             .get()
 316             .expect("`TypedAnnotation::typeck_results` called outside of body")
 317     }
 318 }
 319
 320 impl<'tcx> HirPrinterSupport<'tcx> for TypedAnnotation<'tcx> {
 321     fn sess(&self) -> &Session {
 322         &self.tcx.sess
 323     }
 324
 325     fn hir_map(&self) -> Option<hir_map::Map<'tcx>> {
 326         Some(self.tcx.hir())
 327     }
 328
 329     fn pp_ann(&self) -> &dyn pprust_hir::PpAnn {
 330         self
 331     }
 332
 333     fn node_path(&self, id: hir::HirId) -> Option<String> {
 334         Some(self.tcx.def_path_str(self.tcx.hir().local_def_id(id).to_def_id()))
 335     }
 336 }
 337
 338 impl<'tcx> pprust_hir::PpAnn for TypedAnnotation<'tcx> {
 339     fn nested(&self, state: &mut pprust_hir::State<'_>, nested: pprust_hir::Nested) {
 340         let old_maybe_typeck_results = self.maybe_typeck_results.get();
 341         if let pprust_hir::Nested::Body(id) = nested {
 342             self.maybe_typeck_results.set(Some(self.tcx.typeck_body(id)));
 343         }
 344         let pp_ann = &(&self.tcx.hir() as &dyn hir::intravisit::Map<'_>);
 345         pprust_hir::PpAnn::nested(pp_ann, state, nested);
 346         self.maybe_typeck_results.set(old_maybe_typeck_results);
 347     }
 348     fn pre(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 349         if let pprust_hir::AnnNode::Expr(_) = node {
 350             s.popen();
 351         }
 352     }
 353     fn post(&self, s: &mut pprust_hir::State<'_>, node: pprust_hir::AnnNode<'_>) {
 354         if let pprust_hir::AnnNode::Expr(expr) = node {
 355             s.s.space();
 356             s.s.word("as");
 357             s.s.space();
 358             s.s.word(self.typeck_results().expr_ty(expr).to_string());
 359             s.pclose();
 360         }
 361     }
 362 }
 363
 364 fn get_source(input: &Input, sess: &Session) -> (String, FileName) {
 365     let src_name = input.source_name();
 366     let src = String::clone(
 367         &sess
 368             .source_map()
 369             .get_source_file(&src_name)
 370             .expect("get_source_file")
 371             .src
 372             .as_ref()
 373             .expect("src"),
 374     );
 375     (src, src_name)
 376 }
 377
 378 fn write_output(out: Vec<u8>, ofile: Option<&Path>) {
 379     match ofile {
 380         None => print!("{}", String::from_utf8(out).unwrap()),
 381         Some(p) => match File::create(p) {
 382             Ok(mut w) => w.write_all(&out).unwrap(),
 383             Err(e) => panic!("print-print failed to open {} due to {}", p.display(), e),
 384         },
 385     }
 386 }
 387
 388 pub fn print_after_parsing(
 389     sess: &Session,
 390     input: &Input,
 391     krate: &ast::Crate,
 392     ppm: PpMode,
 393     ofile: Option<&Path>,
 394 ) {
 395     let (src, src_name) = get_source(input, sess);
 396
 397     let mut out = String::new();
 398
 399     if let PpmSource(s) = ppm {
 400         // Silently ignores an identified node.
 401         let out = &mut out;
 402         call_with_pp_support(&s, sess, None, move |annotation| {
 403             debug!("pretty printing source code {:?}", s);
 404             let sess = annotation.sess();
 405             let parse = &sess.parse_sess;
 406             *out = pprust::print_crate(
 407                 sess.source_map(),
 408                 krate,
 409                 src_name,
 410                 src,
 411                 annotation.pp_ann(),
 412                 false,
 413                 parse.edition,
 414             )
 415         })
 416     } else {
 417         unreachable!();
 418     };
 419
 420     write_output(out.into_bytes(), ofile);
 421 }
 422
 423 pub fn print_after_hir_lowering<'tcx>(
 424     tcx: TyCtxt<'tcx>,
 425     input: &Input,
 426     krate: &ast::Crate,
 427     ppm: PpMode,
 428     ofile: Option<&Path>,
 429 ) {
 430     if ppm.needs_analysis() {
 431         abort_on_err(print_with_analysis(tcx, ppm, ofile), tcx.sess);
 432         return;
 433     }
 434
 435     let (src, src_name) = get_source(input, tcx.sess);
 436
 437     let mut out = String::new();
 438
 439     match ppm {
 440         PpmSource(s) => {
 441             // Silently ignores an identified node.
 442             let out = &mut out;
 443             call_with_pp_support(&s, tcx.sess, Some(tcx), move |annotation| {
 444                 debug!("pretty printing source code {:?}", s);
 445                 let sess = annotation.sess();
 446                 let parse = &sess.parse_sess;
 447                 *out = pprust::print_crate(
 448                     sess.source_map(),
 449                     krate,
 450                     src_name,
 451                     src,
 452                     annotation.pp_ann(),
 453                     true,
 454                     parse.edition,
 455                 )
 456             })
 457         }
 458
 459         PpmHir(s) => {
 460             let out = &mut out;
 461             call_with_pp_support_hir(&s, tcx, move |annotation, krate| {
 462                 debug!("pretty printing source code {:?}", s);
 463                 let sess = annotation.sess();
 464                 let sm = sess.source_map();
 465                 *out = pprust_hir::print_crate(sm, krate, src_name, src, annotation.pp_ann())
 466             })
 467         }
 468
 469         PpmHirTree(s) => {
 470             let out = &mut out;
 471             call_with_pp_support_hir(&s, tcx, move |_annotation, krate| {
 472                 debug!("pretty printing source code {:?}", s);
 473                 *out = format!("{:#?}", krate);
 474             });
 475         }
 476
 477         _ => unreachable!(),
 478     }
 479
 480     write_output(out.into_bytes(), ofile);
 481 }
 482
 483 // In an ideal world, this would be a public function called by the driver after
 484 // analysis is performed. However, we want to call `phase_3_run_analysis_passes`
 485 // with a different callback than the standard driver, so that isn't easy.
 486 // Instead, we call that function ourselves.
 487 fn print_with_analysis(
 488     tcx: TyCtxt<'_>,
 489     ppm: PpMode,
 490     ofile: Option<&Path>,
 491 ) -> Result<(), ErrorReported> {
 492     let mut out = Vec::new();
 493
 494     tcx.analysis(LOCAL_CRATE)?;
 495
 496     match ppm {
 497         PpmMir | PpmMirCFG => match ppm {
 498             PpmMir => write_mir_pretty(tcx, None, &mut out),
 499             PpmMirCFG => write_mir_graphviz(tcx, None, &mut out),
 500             _ => unreachable!(),
 501         },
 502         _ => unreachable!(),
 503     }
 504     .unwrap();
 505
 506     write_output(out, ofile);
 507
 508     Ok(())
 509 }