src/librustc_driver/test.rs

   1 // Copyright 2012 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 //! # Standalone Tests for the Inference Module
  12
  13 use diagnostic;
  14 use diagnostic::Emitter;
  15 use driver;
  16 use rustc_lint;
  17 use rustc_resolve as resolve;
  18 use rustc_typeck::middle::lang_items;
  19 use rustc_typeck::middle::free_region::FreeRegionMap;
  20 use rustc_typeck::middle::region::{self, CodeExtent, DestructionScopeData};
  21 use rustc_typeck::middle::resolve_lifetime;
  22 use rustc_typeck::middle::stability;
  23 use rustc_typeck::middle::subst;
  24 use rustc_typeck::middle::subst::Subst;
  25 use rustc_typeck::middle::ty::{self, Ty};
  26 use rustc_typeck::middle::ty_relate::TypeRelation;
  27 use rustc_typeck::middle::infer;
  28 use rustc_typeck::middle::infer::lub::Lub;
  29 use rustc_typeck::middle::infer::glb::Glb;
  30 use rustc_typeck::middle::infer::sub::Sub;
  31 use rustc::ast_map;
  32 use rustc::session::{self,config};
  33 use syntax::{abi, ast};
  34 use syntax::codemap;
  35 use syntax::codemap::{Span, CodeMap, DUMMY_SP};
  36 use syntax::diagnostic::{Level, RenderSpan, Bug, Fatal, Error, Warning, Note, Help};
  37 use syntax::parse::token;
  38 use syntax::feature_gate::UnstableFeatures;
  39
  40 struct Env<'a, 'tcx: 'a> {
  41     infcx: &'a infer::InferCtxt<'a, 'tcx>,
  42 }
  43
  44 struct RH<'a> {
  45     id: ast::NodeId,
  46     sub: &'a [RH<'a>]
  47 }
  48
  49 const EMPTY_SOURCE_STR: &'static str = "#![feature(no_std)] #![no_std]";
  50
  51 struct ExpectErrorEmitter {
  52     messages: Vec<String>
  53 }
  54
  55 fn remove_message(e: &mut ExpectErrorEmitter, msg: &str, lvl: Level) {
  56     match lvl {
  57         Bug | Fatal | Error => { }
  58         Warning | Note | Help => { return; }
  59     }
  60
  61     debug!("Error: {}", msg);
  62     match e.messages.iter().position(|m| msg.contains(m)) {
  63         Some(i) => {
  64             e.messages.remove(i);
  65         }
  66         None => {
  67             panic!("Unexpected error: {} Expected: {:?}",
  68                   msg, e.messages);
  69         }
  70     }
  71 }
  72
  73 impl Emitter for ExpectErrorEmitter {
  74     fn emit(&mut self,
  75             _cmsp: Option<(&codemap::CodeMap, Span)>,
  76             msg: &str,
  77             _: Option<&str>,
  78             lvl: Level)
  79     {
  80         remove_message(self, msg, lvl);
  81     }
  82
  83     fn custom_emit(&mut self,
  84                    _cm: &codemap::CodeMap,
  85                    _sp: RenderSpan,
  86                    msg: &str,
  87                    lvl: Level)
  88     {
  89         remove_message(self, msg, lvl);
  90     }
  91 }
  92
  93 fn errors(msgs: &[&str]) -> (Box<Emitter+Send>, usize) {
  94     let v = msgs.iter().map(|m| m.to_string()).collect();
  95     (box ExpectErrorEmitter { messages: v } as Box<Emitter+Send>, msgs.len())
  96 }
  97
  98 fn test_env<F>(source_string: &str,
  99                (emitter, expected_err_count): (Box<Emitter+Send>, usize),
 100                body: F) where
 101     F: FnOnce(Env),
 102 {
 103     let mut options =
 104         config::basic_options();
 105     options.debugging_opts.verbose = true;
 106     options.unstable_features = UnstableFeatures::Allow;
 107     let codemap =
 108         CodeMap::new();
 109     let diagnostic_handler =
 110         diagnostic::Handler::with_emitter(true, emitter);
 111     let span_diagnostic_handler =
 112         diagnostic::SpanHandler::new(diagnostic_handler, codemap);
 113
 114     let sess = session::build_session_(options, None, span_diagnostic_handler);
 115     rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
 116     let krate_config = Vec::new();
 117     let input = config::Input::Str(source_string.to_string());
 118     let krate = driver::phase_1_parse_input(&sess, krate_config, &input);
 119     let krate = driver::phase_2_configure_and_expand(&sess, krate, "test", None)
 120                     .expect("phase 2 aborted");
 121
 122     let mut forest = ast_map::Forest::new(krate);
 123     let arenas = ty::CtxtArenas::new();
 124     let ast_map = driver::assign_node_ids_and_map(&sess, &mut forest);
 125     let krate = ast_map.krate();
 126
 127     // run just enough stuff to build a tcx:
 128     let lang_items = lang_items::collect_language_items(krate, &sess);
 129     let resolve::CrateMap { def_map, freevars, .. } =
 130         resolve::resolve_crate(&sess, &ast_map, resolve::MakeGlobMap::No);
 131     let named_region_map = resolve_lifetime::krate(&sess, krate, &def_map);
 132     let region_map = region::resolve_crate(&sess, krate);
 133     ty::with_ctxt(sess,
 134                   &arenas,
 135                   def_map,
 136                   named_region_map,
 137                   ast_map,
 138                   freevars,
 139                   region_map,
 140                   lang_items,
 141                   stability::Index::new(krate),
 142                   |tcx| {
 143         let infcx = infer::new_infer_ctxt(tcx);
 144         body(Env { infcx: &infcx });
 145         let free_regions = FreeRegionMap::new();
 146         infcx.resolve_regions_and_report_errors(&free_regions, ast::CRATE_NODE_ID);
 147         assert_eq!(tcx.sess.err_count(), expected_err_count);
 148     });
 149 }
 150
 151 impl<'a, 'tcx> Env<'a, 'tcx> {
 152     pub fn tcx(&self) -> &ty::ctxt<'tcx> {
 153         self.infcx.tcx
 154     }
 155
 156     pub fn create_region_hierarchy(&self, rh: &RH) {
 157         for child_rh in rh.sub {
 158             self.create_region_hierarchy(child_rh);
 159             self.infcx.tcx.region_maps.record_encl_scope(
 160                 CodeExtent::from_node_id(child_rh.id),
 161                 CodeExtent::from_node_id(rh.id));
 162         }
 163     }
 164
 165     pub fn create_simple_region_hierarchy(&self) {
 166         // creates a region hierarchy where 1 is root, 10 and 11 are
 167         // children of 1, etc
 168         self.create_region_hierarchy(
 169             &RH {id: 1,
 170                  sub: &[RH {id: 10,
 171                             sub: &[]},
 172                         RH {id: 11,
 173                             sub: &[]}]});
 174     }
 175
 176     #[allow(dead_code)] // this seems like it could be useful, even if we don't use it now
 177     pub fn lookup_item(&self, names: &[String]) -> ast::NodeId {
 178         return match search_mod(self, &self.infcx.tcx.map.krate().module, 0, names) {
 179             Some(id) => id,
 180             None => {
 181                 panic!("no item found: `{}`", names.connect("::"));
 182             }
 183         };
 184
 185         fn search_mod(this: &Env,
 186                       m: &ast::Mod,
 187                       idx: usize,
 188                       names: &[String])
 189                       -> Option<ast::NodeId> {
 190             assert!(idx < names.len());
 191             for item in &m.items {
 192                 if item.ident.to_string() == names[idx] {
 193                     return search(this, &**item, idx+1, names);
 194                 }
 195             }
 196             return None;
 197         }
 198
 199         fn search(this: &Env,
 200                   it: &ast::Item,
 201                   idx: usize,
 202                   names: &[String])
 203                   -> Option<ast::NodeId> {
 204             if idx == names.len() {
 205                 return Some(it.id);
 206             }
 207
 208             return match it.node {
 209                 ast::ItemUse(..) | ast::ItemExternCrate(..) |
 210                 ast::ItemConst(..) | ast::ItemStatic(..) | ast::ItemFn(..) |
 211                 ast::ItemForeignMod(..) | ast::ItemTy(..) => {
 212                     None
 213                 }
 214
 215                 ast::ItemEnum(..) | ast::ItemStruct(..) |
 216                 ast::ItemTrait(..) | ast::ItemImpl(..) |
 217                 ast::ItemMac(..) | ast::ItemDefaultImpl(..) => {
 218                     None
 219                 }
 220
 221                 ast::ItemMod(ref m) => {
 222                     search_mod(this, m, idx, names)
 223                 }
 224             };
 225         }
 226     }
 227
 228     pub fn make_subtype(&self, a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
 229         match infer::mk_subty(self.infcx, true, infer::Misc(DUMMY_SP), a, b) {
 230             Ok(_) => true,
 231             Err(ref e) => panic!("Encountered error: {}", e)
 232         }
 233     }
 234
 235     pub fn is_subtype(&self, a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
 236         match infer::can_mk_subty(self.infcx, a, b) {
 237             Ok(_) => true,
 238             Err(_) => false
 239         }
 240     }
 241
 242     pub fn assert_subtype(&self, a: Ty<'tcx>, b: Ty<'tcx>) {
 243         if !self.is_subtype(a, b) {
 244             panic!("{} is not a subtype of {}, but it should be", a, b);
 245         }
 246     }
 247
 248     pub fn assert_eq(&self, a: Ty<'tcx>, b: Ty<'tcx>) {
 249         self.assert_subtype(a, b);
 250         self.assert_subtype(b, a);
 251     }
 252
 253     pub fn t_fn(&self,
 254                 input_tys: &[Ty<'tcx>],
 255                 output_ty: Ty<'tcx>)
 256                 -> Ty<'tcx>
 257     {
 258         let input_args = input_tys.iter().cloned().collect();
 259         ty::mk_bare_fn(self.infcx.tcx,
 260                        None,
 261                        self.infcx.tcx.mk_bare_fn(ty::BareFnTy {
 262                            unsafety: ast::Unsafety::Normal,
 263                            abi: abi::Rust,
 264                            sig: ty::Binder(ty::FnSig {
 265                                inputs: input_args,
 266                                output: ty::FnConverging(output_ty),
 267                                variadic: false
 268                            })
 269                        }))
 270     }
 271
 272     pub fn t_nil(&self) -> Ty<'tcx> {
 273         ty::mk_nil(self.infcx.tcx)
 274     }
 275
 276     pub fn t_pair(&self, ty1: Ty<'tcx>, ty2: Ty<'tcx>) -> Ty<'tcx> {
 277         ty::mk_tup(self.infcx.tcx, vec![ty1, ty2])
 278     }
 279
 280     pub fn t_param(&self, space: subst::ParamSpace, index: u32) -> Ty<'tcx> {
 281         let name = format!("T{}", index);
 282         ty::mk_param(self.infcx.tcx, space, index, token::intern(&name[..]))
 283     }
 284
 285     pub fn re_early_bound(&self,
 286                           space: subst::ParamSpace,
 287                           index: u32,
 288                           name: &'static str)
 289                           -> ty::Region
 290     {
 291         let name = token::intern(name);
 292         ty::ReEarlyBound(ty::EarlyBoundRegion {
 293             param_id: ast::DUMMY_NODE_ID,
 294             space: space,
 295             index: index,
 296             name: name
 297         })
 298     }
 299
 300     pub fn re_late_bound_with_debruijn(&self, id: u32, debruijn: ty::DebruijnIndex) -> ty::Region {
 301         ty::ReLateBound(debruijn, ty::BrAnon(id))
 302     }
 303
 304     pub fn t_rptr(&self, r: ty::Region) -> Ty<'tcx> {
 305         ty::mk_imm_rptr(self.infcx.tcx,
 306                         self.infcx.tcx.mk_region(r),
 307                         self.tcx().types.isize)
 308     }
 309
 310     pub fn t_rptr_late_bound(&self, id: u32) -> Ty<'tcx> {
 311         let r = self.re_late_bound_with_debruijn(id, ty::DebruijnIndex::new(1));
 312         ty::mk_imm_rptr(self.infcx.tcx,
 313                         self.infcx.tcx.mk_region(r),
 314                         self.tcx().types.isize)
 315     }
 316
 317     pub fn t_rptr_late_bound_with_debruijn(&self,
 318                                            id: u32,
 319                                            debruijn: ty::DebruijnIndex)
 320                                            -> Ty<'tcx> {
 321         let r = self.re_late_bound_with_debruijn(id, debruijn);
 322         ty::mk_imm_rptr(self.infcx.tcx,
 323                         self.infcx.tcx.mk_region(r),
 324                         self.tcx().types.isize)
 325     }
 326
 327     pub fn t_rptr_scope(&self, id: ast::NodeId) -> Ty<'tcx> {
 328         let r = ty::ReScope(CodeExtent::from_node_id(id));
 329         ty::mk_imm_rptr(self.infcx.tcx, self.infcx.tcx.mk_region(r),
 330                         self.tcx().types.isize)
 331     }
 332
 333     pub fn re_free(&self, nid: ast::NodeId, id: u32) -> ty::Region {
 334         ty::ReFree(ty::FreeRegion { scope: DestructionScopeData::new(nid),
 335                                     bound_region: ty::BrAnon(id)})
 336     }
 337
 338     pub fn t_rptr_free(&self, nid: ast::NodeId, id: u32) -> Ty<'tcx> {
 339         let r = self.re_free(nid, id);
 340         ty::mk_imm_rptr(self.infcx.tcx,
 341                         self.infcx.tcx.mk_region(r),
 342                         self.tcx().types.isize)
 343     }
 344
 345     pub fn t_rptr_static(&self) -> Ty<'tcx> {
 346         ty::mk_imm_rptr(self.infcx.tcx,
 347                         self.infcx.tcx.mk_region(ty::ReStatic),
 348                         self.tcx().types.isize)
 349     }
 350
 351     pub fn dummy_type_trace(&self) -> infer::TypeTrace<'tcx> {
 352         infer::TypeTrace::dummy(self.tcx())
 353     }
 354
 355     pub fn sub(&self) -> Sub<'a, 'tcx> {
 356         let trace = self.dummy_type_trace();
 357         self.infcx.sub(true, trace)
 358     }
 359
 360     pub fn lub(&self) -> Lub<'a, 'tcx> {
 361         let trace = self.dummy_type_trace();
 362         self.infcx.lub(true, trace)
 363     }
 364
 365     pub fn glb(&self) -> Glb<'a, 'tcx> {
 366         let trace = self.dummy_type_trace();
 367         self.infcx.glb(true, trace)
 368     }
 369
 370     pub fn make_lub_ty(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) -> Ty<'tcx> {
 371         match self.lub().relate(&t1, &t2) {
 372             Ok(t) => t,
 373             Err(ref e) => panic!("unexpected error computing LUB: {}", e)
 374         }
 375     }
 376
 377     /// Checks that `t1 <: t2` is true (this may register additional
 378     /// region checks).
 379     pub fn check_sub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) {
 380         match self.sub().relate(&t1, &t2) {
 381             Ok(_) => { }
 382             Err(ref e) => {
 383                 panic!("unexpected error computing sub({:?},{:?}): {}",
 384                        t1,
 385                        t2,
 386                        e);
 387             }
 388         }
 389     }
 390
 391     /// Checks that `t1 <: t2` is false (this may register additional
 392     /// region checks).
 393     pub fn check_not_sub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) {
 394         match self.sub().relate(&t1, &t2) {
 395             Err(_) => { }
 396             Ok(_) => {
 397                 panic!("unexpected success computing sub({:?},{:?})",
 398                        t1,
 399                        t2);
 400             }
 401         }
 402     }
 403
 404     /// Checks that `LUB(t1,t2) == t_lub`
 405     pub fn check_lub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>, t_lub: Ty<'tcx>) {
 406         match self.lub().relate(&t1, &t2) {
 407             Ok(t) => {
 408                 self.assert_eq(t, t_lub);
 409             }
 410             Err(ref e) => {
 411                 panic!("unexpected error in LUB: {}", e)
 412             }
 413         }
 414     }
 415
 416     /// Checks that `GLB(t1,t2) == t_glb`
 417     pub fn check_glb(&self, t1: Ty<'tcx>, t2: Ty<'tcx>, t_glb: Ty<'tcx>) {
 418         debug!("check_glb(t1={}, t2={}, t_glb={})", t1, t2, t_glb);
 419         match self.glb().relate(&t1, &t2) {
 420             Err(e) => {
 421                 panic!("unexpected error computing LUB: {:?}", e)
 422             }
 423             Ok(t) => {
 424                 self.assert_eq(t, t_glb);
 425
 426                 // sanity check for good measure:
 427                 self.assert_subtype(t, t1);
 428                 self.assert_subtype(t, t2);
 429             }
 430         }
 431     }
 432 }
 433
 434 #[test]
 435 fn contravariant_region_ptr_ok() {
 436     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 437         env.create_simple_region_hierarchy();
 438         let t_rptr1 = env.t_rptr_scope(1);
 439         let t_rptr10 = env.t_rptr_scope(10);
 440         env.assert_eq(t_rptr1, t_rptr1);
 441         env.assert_eq(t_rptr10, t_rptr10);
 442         env.make_subtype(t_rptr1, t_rptr10);
 443     })
 444 }
 445
 446 #[test]
 447 fn contravariant_region_ptr_err() {
 448     test_env(EMPTY_SOURCE_STR,
 449              errors(&["lifetime mismatch"]),
 450              |env| {
 451                  env.create_simple_region_hierarchy();
 452                  let t_rptr1 = env.t_rptr_scope(1);
 453                  let t_rptr10 = env.t_rptr_scope(10);
 454                  env.assert_eq(t_rptr1, t_rptr1);
 455                  env.assert_eq(t_rptr10, t_rptr10);
 456
 457                  // will cause an error when regions are resolved
 458                  env.make_subtype(t_rptr10, t_rptr1);
 459              })
 460 }
 461
 462 #[test]
 463 fn sub_free_bound_false() {
 464     //! Test that:
 465     //!
 466     //!     fn(&'a isize) <: for<'b> fn(&'b isize)
 467     //!
 468     //! does NOT hold.
 469
 470     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 471         let t_rptr_free1 = env.t_rptr_free(0, 1);
 472         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 473         env.check_not_sub(env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
 474                           env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 475     })
 476 }
 477
 478 #[test]
 479 fn sub_bound_free_true() {
 480     //! Test that:
 481     //!
 482     //!     for<'a> fn(&'a isize) <: fn(&'b isize)
 483     //!
 484     //! DOES hold.
 485
 486     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 487         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 488         let t_rptr_free1 = env.t_rptr_free(0, 1);
 489         env.check_sub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 490                       env.t_fn(&[t_rptr_free1], env.tcx().types.isize));
 491     })
 492 }
 493
 494 #[test]
 495 fn sub_free_bound_false_infer() {
 496     //! Test that:
 497     //!
 498     //!     fn(_#1) <: for<'b> fn(&'b isize)
 499     //!
 500     //! does NOT hold for any instantiation of `_#1`.
 501
 502     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 503         let t_infer1 = env.infcx.next_ty_var();
 504         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 505         env.check_not_sub(env.t_fn(&[t_infer1], env.tcx().types.isize),
 506                           env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 507     })
 508 }
 509
 510 #[test]
 511 fn lub_free_bound_infer() {
 512     //! Test result of:
 513     //!
 514     //!     LUB(fn(_#1), for<'b> fn(&'b isize))
 515     //!
 516     //! This should yield `fn(&'_ isize)`. We check
 517     //! that it yields `fn(&'x isize)` for some free `'x`,
 518     //! anyhow.
 519
 520     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 521         let t_infer1 = env.infcx.next_ty_var();
 522         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 523         let t_rptr_free1 = env.t_rptr_free(0, 1);
 524         env.check_lub(env.t_fn(&[t_infer1], env.tcx().types.isize),
 525                       env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 526                       env.t_fn(&[t_rptr_free1], env.tcx().types.isize));
 527     });
 528 }
 529
 530 #[test]
 531 fn lub_bound_bound() {
 532     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 533         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 534         let t_rptr_bound2 = env.t_rptr_late_bound(2);
 535         env.check_lub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 536                       env.t_fn(&[t_rptr_bound2], env.tcx().types.isize),
 537                       env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 538     })
 539 }
 540
 541 #[test]
 542 fn lub_bound_free() {
 543     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 544         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 545         let t_rptr_free1 = env.t_rptr_free(0, 1);
 546         env.check_lub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 547                       env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
 548                       env.t_fn(&[t_rptr_free1], env.tcx().types.isize));
 549     })
 550 }
 551
 552 #[test]
 553 fn lub_bound_static() {
 554     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 555         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 556         let t_rptr_static = env.t_rptr_static();
 557         env.check_lub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 558                       env.t_fn(&[t_rptr_static], env.tcx().types.isize),
 559                       env.t_fn(&[t_rptr_static], env.tcx().types.isize));
 560     })
 561 }
 562
 563 #[test]
 564 fn lub_bound_bound_inverse_order() {
 565     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 566         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 567         let t_rptr_bound2 = env.t_rptr_late_bound(2);
 568         env.check_lub(env.t_fn(&[t_rptr_bound1, t_rptr_bound2], t_rptr_bound1),
 569                       env.t_fn(&[t_rptr_bound2, t_rptr_bound1], t_rptr_bound1),
 570                       env.t_fn(&[t_rptr_bound1, t_rptr_bound1], t_rptr_bound1));
 571     })
 572 }
 573
 574 #[test]
 575 fn lub_free_free() {
 576     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 577         let t_rptr_free1 = env.t_rptr_free(0, 1);
 578         let t_rptr_free2 = env.t_rptr_free(0, 2);
 579         let t_rptr_static = env.t_rptr_static();
 580         env.check_lub(env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
 581                       env.t_fn(&[t_rptr_free2], env.tcx().types.isize),
 582                       env.t_fn(&[t_rptr_static], env.tcx().types.isize));
 583     })
 584 }
 585
 586 #[test]
 587 fn lub_returning_scope() {
 588     test_env(EMPTY_SOURCE_STR,
 589              errors(&["cannot infer an appropriate lifetime"]), |env| {
 590                  env.create_simple_region_hierarchy();
 591                  let t_rptr_scope10 = env.t_rptr_scope(10);
 592                  let t_rptr_scope11 = env.t_rptr_scope(11);
 593
 594                  // this should generate an error when regions are resolved
 595                  env.make_lub_ty(env.t_fn(&[], t_rptr_scope10),
 596                                  env.t_fn(&[], t_rptr_scope11));
 597              })
 598 }
 599
 600 #[test]
 601 fn glb_free_free_with_common_scope() {
 602     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 603         let t_rptr_free1 = env.t_rptr_free(0, 1);
 604         let t_rptr_free2 = env.t_rptr_free(0, 2);
 605         let t_rptr_scope = env.t_rptr_scope(0);
 606         env.check_glb(env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
 607                       env.t_fn(&[t_rptr_free2], env.tcx().types.isize),
 608                       env.t_fn(&[t_rptr_scope], env.tcx().types.isize));
 609     })
 610 }
 611
 612 #[test]
 613 fn glb_bound_bound() {
 614     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 615         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 616         let t_rptr_bound2 = env.t_rptr_late_bound(2);
 617         env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 618                       env.t_fn(&[t_rptr_bound2], env.tcx().types.isize),
 619                       env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 620     })
 621 }
 622
 623 #[test]
 624 fn glb_bound_free() {
 625     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 626         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 627         let t_rptr_free1 = env.t_rptr_free(0, 1);
 628         env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 629                       env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
 630                       env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 631     })
 632 }
 633
 634 #[test]
 635 fn glb_bound_free_infer() {
 636     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 637         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 638         let t_infer1 = env.infcx.next_ty_var();
 639
 640         // compute GLB(fn(_) -> isize, for<'b> fn(&'b isize) -> isize),
 641         // which should yield for<'b> fn(&'b isize) -> isize
 642         env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 643                       env.t_fn(&[t_infer1], env.tcx().types.isize),
 644                       env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 645
 646         // as a side-effect, computing GLB should unify `_` with
 647         // `&'_ isize`
 648         let t_resolve1 = env.infcx.shallow_resolve(t_infer1);
 649         match t_resolve1.sty {
 650             ty::TyRef(..) => { }
 651             _ => { panic!("t_resolve1={:?}", t_resolve1); }
 652         }
 653     })
 654 }
 655
 656 #[test]
 657 fn glb_bound_static() {
 658     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 659         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 660         let t_rptr_static = env.t_rptr_static();
 661         env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
 662                       env.t_fn(&[t_rptr_static], env.tcx().types.isize),
 663                       env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
 664     })
 665 }
 666
 667 /// Test substituting a bound region into a function, which introduces another level of binding.
 668 /// This requires adjusting the Debruijn index.
 669 #[test]
 670 fn subst_ty_renumber_bound() {
 671
 672     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 673         // Situation:
 674         // Theta = [A -> &'a foo]
 675
 676         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 677
 678         // t_source = fn(A)
 679         let t_source = {
 680             let t_param = env.t_param(subst::TypeSpace, 0);
 681             env.t_fn(&[t_param], env.t_nil())
 682         };
 683
 684         let substs = subst::Substs::new_type(vec![t_rptr_bound1], vec![]);
 685         let t_substituted = t_source.subst(env.infcx.tcx, &substs);
 686
 687         // t_expected = fn(&'a isize)
 688         let t_expected = {
 689             let t_ptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
 690             env.t_fn(&[t_ptr_bound2], env.t_nil())
 691         };
 692
 693         debug!("subst_bound: t_source={:?} substs={:?} t_substituted={:?} t_expected={:?}",
 694                t_source,
 695                substs,
 696                t_substituted,
 697                t_expected);
 698
 699         assert_eq!(t_substituted, t_expected);
 700     })
 701 }
 702
 703 /// Test substituting a bound region into a function, which introduces another level of binding.
 704 /// This requires adjusting the Debruijn index.
 705 #[test]
 706 fn subst_ty_renumber_some_bounds() {
 707     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 708         // Situation:
 709         // Theta = [A -> &'a foo]
 710
 711         let t_rptr_bound1 = env.t_rptr_late_bound(1);
 712
 713         // t_source = (A, fn(A))
 714         let t_source = {
 715             let t_param = env.t_param(subst::TypeSpace, 0);
 716             env.t_pair(t_param, env.t_fn(&[t_param], env.t_nil()))
 717         };
 718
 719         let substs = subst::Substs::new_type(vec![t_rptr_bound1], vec![]);
 720         let t_substituted = t_source.subst(env.infcx.tcx, &substs);
 721
 722         // t_expected = (&'a isize, fn(&'a isize))
 723         //
 724         // but not that the Debruijn index is different in the different cases.
 725         let t_expected = {
 726             let t_rptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
 727             env.t_pair(t_rptr_bound1, env.t_fn(&[t_rptr_bound2], env.t_nil()))
 728         };
 729
 730         debug!("subst_bound: t_source={:?} substs={:?} t_substituted={:?} t_expected={:?}",
 731                t_source,
 732                substs,
 733                t_substituted,
 734                t_expected);
 735
 736         assert_eq!(t_substituted, t_expected);
 737     })
 738 }
 739
 740 /// Test that we correctly compute whether a type has escaping regions or not.
 741 #[test]
 742 fn escaping() {
 743
 744     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 745         // Situation:
 746         // Theta = [A -> &'a foo]
 747
 748         assert!(!ty::type_has_escaping_regions(env.t_nil()));
 749
 750         let t_rptr_free1 = env.t_rptr_free(0, 1);
 751         assert!(!ty::type_has_escaping_regions(t_rptr_free1));
 752
 753         let t_rptr_bound1 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(1));
 754         assert!(ty::type_has_escaping_regions(t_rptr_bound1));
 755
 756         let t_rptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
 757         assert!(ty::type_has_escaping_regions(t_rptr_bound2));
 758
 759         // t_fn = fn(A)
 760         let t_param = env.t_param(subst::TypeSpace, 0);
 761         assert!(!ty::type_has_escaping_regions(t_param));
 762         let t_fn = env.t_fn(&[t_param], env.t_nil());
 763         assert!(!ty::type_has_escaping_regions(t_fn));
 764     })
 765 }
 766
 767 /// Test applying a substitution where the value being substituted for an early-bound region is a
 768 /// late-bound region.
 769 #[test]
 770 fn subst_region_renumber_region() {
 771     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 772         let re_bound1 = env.re_late_bound_with_debruijn(1, ty::DebruijnIndex::new(1));
 773
 774         // type t_source<'a> = fn(&'a isize)
 775         let t_source = {
 776             let re_early = env.re_early_bound(subst::TypeSpace, 0, "'a");
 777             env.t_fn(&[env.t_rptr(re_early)], env.t_nil())
 778         };
 779
 780         let substs = subst::Substs::new_type(vec![], vec![re_bound1]);
 781         let t_substituted = t_source.subst(env.infcx.tcx, &substs);
 782
 783         // t_expected = fn(&'a isize)
 784         //
 785         // but not that the Debruijn index is different in the different cases.
 786         let t_expected = {
 787             let t_rptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
 788             env.t_fn(&[t_rptr_bound2], env.t_nil())
 789         };
 790
 791         debug!("subst_bound: t_source={:?} substs={:?} t_substituted={:?} t_expected={:?}",
 792                t_source,
 793                substs,
 794                t_substituted,
 795                t_expected);
 796
 797         assert_eq!(t_substituted, t_expected);
 798     })
 799 }
 800
 801 #[test]
 802 fn walk_ty() {
 803     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 804         let tcx = env.infcx.tcx;
 805         let int_ty = tcx.types.isize;
 806         let uint_ty = tcx.types.usize;
 807         let tup1_ty = ty::mk_tup(tcx, vec!(int_ty, uint_ty, int_ty, uint_ty));
 808         let tup2_ty = ty::mk_tup(tcx, vec!(tup1_ty, tup1_ty, uint_ty));
 809         let uniq_ty = ty::mk_uniq(tcx, tup2_ty);
 810         let walked: Vec<_> = uniq_ty.walk().collect();
 811         assert_eq!(walked, [uniq_ty,
 812                             tup2_ty,
 813                             tup1_ty, int_ty, uint_ty, int_ty, uint_ty,
 814                             tup1_ty, int_ty, uint_ty, int_ty, uint_ty,
 815                             uint_ty]);
 816     })
 817 }
 818
 819 #[test]
 820 fn walk_ty_skip_subtree() {
 821     test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
 822         let tcx = env.infcx.tcx;
 823         let int_ty = tcx.types.isize;
 824         let uint_ty = tcx.types.usize;
 825         let tup1_ty = ty::mk_tup(tcx, vec!(int_ty, uint_ty, int_ty, uint_ty));
 826         let tup2_ty = ty::mk_tup(tcx, vec!(tup1_ty, tup1_ty, uint_ty));
 827         let uniq_ty = ty::mk_uniq(tcx, tup2_ty);
 828
 829         // types we expect to see (in order), plus a boolean saying
 830         // whether to skip the subtree.
 831         let mut expected = vec!((uniq_ty, false),
 832                                 (tup2_ty, false),
 833                                 (tup1_ty, false),
 834                                 (int_ty, false),
 835                                 (uint_ty, false),
 836                                 (int_ty, false),
 837                                 (uint_ty, false),
 838                                 (tup1_ty, true), // skip the isize/usize/isize/usize
 839                                 (uint_ty, false));
 840         expected.reverse();
 841
 842         let mut walker = uniq_ty.walk();
 843         while let Some(t) = walker.next() {
 844             debug!("walked to {:?}", t);
 845             let (expected_ty, skip) = expected.pop().unwrap();
 846             assert_eq!(t, expected_ty);
 847             if skip { walker.skip_current_subtree(); }
 848         }
 849
 850         assert!(expected.is_empty());
 851     })
 852 }