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.
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.
11 //! # Standalone Tests for the Inference Module
14 use rustc::dep_graph::DepGraph;
16 use rustc_resolve::MakeGlobMap;
17 use rustc::middle::lang_items;
18 use rustc::middle::free_region::FreeRegionMap;
19 use rustc::middle::region::{self, CodeExtent};
20 use rustc::middle::region::CodeExtentData;
21 use rustc::middle::resolve_lifetime;
22 use rustc::middle::stability;
23 use rustc::ty::subst::{Kind, Subst};
24 use rustc::traits::{ObligationCause, Reveal};
25 use rustc::ty::{self, Ty, TyCtxt, TypeFoldable};
26 use rustc::infer::{self, InferOk, InferResult};
27 use rustc::infer::type_variable::TypeVariableOrigin;
28 use rustc_metadata::cstore::CStore;
29 use rustc::hir::map as hir_map;
30 use rustc::session::{self, config};
34 use syntax::codemap::CodeMap;
36 use errors::emitter::Emitter;
37 use errors::{Level, DiagnosticBuilder};
38 use syntax::feature_gate::UnstableFeatures;
39 use syntax::symbol::Symbol;
40 use syntax_pos::DUMMY_SP;
41 use arena::DroplessArena;
45 struct Env<'a, 'gcx: 'a + 'tcx, 'tcx: 'a> {
46 infcx: &'a infer::InferCtxt<'a, 'gcx, 'tcx>,
54 const EMPTY_SOURCE_STR: &'static str = "#![feature(no_core)] #![no_core]";
56 struct ExpectErrorEmitter {
57 messages: Vec<String>,
60 fn remove_message(e: &mut ExpectErrorEmitter, msg: &str, lvl: Level) {
62 Level::Bug | Level::Fatal | Level::Error => {}
68 debug!("Error: {}", msg);
69 match e.messages.iter().position(|m| msg.contains(m)) {
74 debug!("Unexpected error: {} Expected: {:?}", msg, e.messages);
75 panic!("Unexpected error: {} Expected: {:?}", msg, e.messages);
80 impl Emitter for ExpectErrorEmitter {
81 fn emit(&mut self, db: &DiagnosticBuilder) {
82 remove_message(self, &db.message(), db.level);
83 for child in &db.children {
84 remove_message(self, &child.message(), child.level);
89 fn errors(msgs: &[&str]) -> (Box<Emitter + Send>, usize) {
90 let v = msgs.iter().map(|m| m.to_string()).collect();
91 (box ExpectErrorEmitter { messages: v } as Box<Emitter + Send>, msgs.len())
94 fn test_env<F>(source_string: &str,
95 (emitter, expected_err_count): (Box<Emitter + Send>, usize),
99 let mut options = config::basic_options();
100 options.debugging_opts.verbose = true;
101 options.unstable_features = UnstableFeatures::Allow;
102 let diagnostic_handler = errors::Handler::with_emitter(true, false, emitter);
104 let dep_graph = DepGraph::new(false);
105 let _ignore = dep_graph.in_ignore();
106 let cstore = Rc::new(CStore::new(&dep_graph));
107 let sess = session::build_session_(options,
111 Rc::new(CodeMap::new()),
113 rustc_lint::register_builtins(&mut sess.lint_store.borrow_mut(), Some(&sess));
114 let input = config::Input::Str {
115 name: driver::anon_src(),
116 input: source_string.to_string(),
118 let krate = driver::phase_1_parse_input(&sess, &input).unwrap();
119 let driver::ExpansionResult { defs, resolutions, mut hir_forest, .. } = {
120 driver::phase_2_configure_and_expand(&sess,
128 .expect("phase 2 aborted")
130 let _ignore = dep_graph.in_ignore();
132 let arena = DroplessArena::new();
133 let arenas = ty::GlobalArenas::new();
134 let hir_map = hir_map::map_crate(&mut hir_forest, defs);
136 // run just enough stuff to build a tcx:
137 let lang_items = lang_items::collect_language_items(&sess, &hir_map);
138 let named_region_map = resolve_lifetime::krate(&sess, &hir_map);
139 let region_map = region::resolve_crate(&sess, &hir_map);
140 let index = stability::Index::new(&hir_map);
141 TyCtxt::create_and_enter(&sess,
142 ty::maps::Providers::default(),
143 ty::maps::Providers::default(),
147 named_region_map.unwrap(),
154 tcx.infer_ctxt((), Reveal::UserFacing).enter(|infcx| {
156 body(Env { infcx: &infcx });
157 let free_regions = FreeRegionMap::new();
158 infcx.resolve_regions_and_report_errors(&free_regions, ast::CRATE_NODE_ID);
159 assert_eq!(tcx.sess.err_count(), expected_err_count);
164 impl<'a, 'gcx, 'tcx> Env<'a, 'gcx, 'tcx> {
165 pub fn tcx(&self) -> TyCtxt<'a, 'gcx, 'tcx> {
169 pub fn create_region_hierarchy(&self, rh: &RH, parent: CodeExtent) {
170 let me = self.infcx.tcx.region_maps.intern_node(rh.id, parent);
171 for child_rh in rh.sub {
172 self.create_region_hierarchy(child_rh, me);
176 pub fn create_simple_region_hierarchy(&self) {
177 // creates a region hierarchy where 1 is root, 10 and 11 are
178 // children of 1, etc
180 let node = ast::NodeId::from_u32;
181 let dscope = self.infcx
184 .intern_code_extent(CodeExtentData::DestructionScope(node(1)),
185 region::ROOT_CODE_EXTENT);
186 self.create_region_hierarchy(&RH {
200 #[allow(dead_code)] // this seems like it could be useful, even if we don't use it now
201 pub fn lookup_item(&self, names: &[String]) -> ast::NodeId {
202 return match search_mod(self, &self.infcx.tcx.hir.krate().module, 0, names) {
205 panic!("no item found: `{}`", names.join("::"));
209 fn search_mod(this: &Env,
213 -> Option<ast::NodeId> {
214 assert!(idx < names.len());
215 for item in &m.item_ids {
216 let item = this.infcx.tcx.hir.expect_item(item.id);
217 if item.name.to_string() == names[idx] {
218 return search(this, item, idx + 1, names);
224 fn search(this: &Env, it: &hir::Item, idx: usize, names: &[String]) -> Option<ast::NodeId> {
225 if idx == names.len() {
229 return match it.node {
231 hir::ItemExternCrate(..) |
233 hir::ItemStatic(..) |
235 hir::ItemForeignMod(..) |
236 hir::ItemGlobalAsm(..) |
237 hir::ItemTy(..) => None,
240 hir::ItemStruct(..) |
244 hir::ItemDefaultImpl(..) => None,
246 hir::ItemMod(ref m) => search_mod(this, m, idx, names),
251 pub fn make_subtype(&self, a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
252 match self.infcx.sub_types(true, &ObligationCause::dummy(), a, b) {
254 Err(ref e) => panic!("Encountered error: {}", e),
258 pub fn is_subtype(&self, a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
259 self.infcx.can_sub_types(a, b).is_ok()
262 pub fn assert_subtype(&self, a: Ty<'tcx>, b: Ty<'tcx>) {
263 if !self.is_subtype(a, b) {
264 panic!("{} is not a subtype of {}, but it should be", a, b);
268 pub fn assert_eq(&self, a: Ty<'tcx>, b: Ty<'tcx>) {
269 self.assert_subtype(a, b);
270 self.assert_subtype(b, a);
273 pub fn t_fn(&self, input_tys: &[Ty<'tcx>], output_ty: Ty<'tcx>) -> Ty<'tcx> {
274 self.infcx.tcx.mk_fn_ptr(ty::Binder(self.infcx.tcx.mk_fn_sig(
275 input_tys.iter().cloned(),
278 hir::Unsafety::Normal,
283 pub fn t_nil(&self) -> Ty<'tcx> {
284 self.infcx.tcx.mk_nil()
287 pub fn t_pair(&self, ty1: Ty<'tcx>, ty2: Ty<'tcx>) -> Ty<'tcx> {
288 self.infcx.tcx.intern_tup(&[ty1, ty2], false)
291 pub fn t_param(&self, index: u32) -> Ty<'tcx> {
292 let name = format!("T{}", index);
293 self.infcx.tcx.mk_param(index, Symbol::intern(&name))
296 pub fn re_early_bound(&self, index: u32, name: &'static str) -> &'tcx ty::Region {
297 let name = Symbol::intern(name);
298 self.infcx.tcx.mk_region(ty::ReEarlyBound(ty::EarlyBoundRegion {
304 pub fn re_late_bound_with_debruijn(&self,
306 debruijn: ty::DebruijnIndex)
307 -> &'tcx ty::Region {
308 self.infcx.tcx.mk_region(ty::ReLateBound(debruijn, ty::BrAnon(id)))
311 pub fn t_rptr(&self, r: &'tcx ty::Region) -> Ty<'tcx> {
312 self.infcx.tcx.mk_imm_ref(r, self.tcx().types.isize)
315 pub fn t_rptr_late_bound(&self, id: u32) -> Ty<'tcx> {
316 let r = self.re_late_bound_with_debruijn(id, ty::DebruijnIndex::new(1));
317 self.infcx.tcx.mk_imm_ref(r, self.tcx().types.isize)
320 pub fn t_rptr_late_bound_with_debruijn(&self,
322 debruijn: ty::DebruijnIndex)
324 let r = self.re_late_bound_with_debruijn(id, debruijn);
325 self.infcx.tcx.mk_imm_ref(r, self.tcx().types.isize)
328 pub fn t_rptr_scope(&self, id: u32) -> Ty<'tcx> {
329 let r = ty::ReScope(self.tcx().region_maps.node_extent(ast::NodeId::from_u32(id)));
330 self.infcx.tcx.mk_imm_ref(self.infcx.tcx.mk_region(r), self.tcx().types.isize)
333 pub fn re_free(&self, nid: ast::NodeId, id: u32) -> &'tcx ty::Region {
334 self.infcx.tcx.mk_region(ty::ReFree(ty::FreeRegion {
335 scope: self.tcx().region_maps.item_extent(nid),
336 bound_region: ty::BrAnon(id),
340 pub fn t_rptr_free(&self, nid: u32, id: u32) -> Ty<'tcx> {
341 let r = self.re_free(ast::NodeId::from_u32(nid), id);
342 self.infcx.tcx.mk_imm_ref(r, self.tcx().types.isize)
345 pub fn t_rptr_static(&self) -> Ty<'tcx> {
346 self.infcx.tcx.mk_imm_ref(self.infcx.tcx.types.re_static,
347 self.tcx().types.isize)
350 pub fn t_rptr_empty(&self) -> Ty<'tcx> {
351 self.infcx.tcx.mk_imm_ref(self.infcx.tcx.types.re_empty,
352 self.tcx().types.isize)
355 pub fn dummy_type_trace(&self) -> infer::TypeTrace<'tcx> {
356 infer::TypeTrace::dummy(self.tcx())
359 pub fn sub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) -> InferResult<'tcx, Ty<'tcx>> {
360 let trace = self.dummy_type_trace();
361 self.infcx.sub(true, trace, &t1, &t2)
364 pub fn lub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) -> InferResult<'tcx, Ty<'tcx>> {
365 let trace = self.dummy_type_trace();
366 self.infcx.lub(true, trace, &t1, &t2)
369 pub fn glb(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) -> InferResult<'tcx, Ty<'tcx>> {
370 let trace = self.dummy_type_trace();
371 self.infcx.glb(true, trace, &t1, &t2)
374 /// Checks that `t1 <: t2` is true (this may register additional
376 pub fn check_sub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) {
377 match self.sub(t1, t2) {
378 Ok(InferOk { obligations, .. }) => {
379 // None of these tests should require nested obligations:
380 assert!(obligations.is_empty());
383 panic!("unexpected error computing sub({:?},{:?}): {}", t1, t2, e);
388 /// Checks that `t1 <: t2` is false (this may register additional
390 pub fn check_not_sub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) {
391 match self.sub(t1, t2) {
394 panic!("unexpected success computing sub({:?},{:?})", t1, t2);
399 /// Checks that `LUB(t1,t2) == t_lub`
400 pub fn check_lub(&self, t1: Ty<'tcx>, t2: Ty<'tcx>, t_lub: Ty<'tcx>) {
401 match self.lub(t1, t2) {
402 Ok(InferOk { obligations, value: t }) => {
403 // None of these tests should require nested obligations:
404 assert!(obligations.is_empty());
406 self.assert_eq(t, t_lub);
408 Err(ref e) => panic!("unexpected error in LUB: {}", e),
412 /// Checks that `GLB(t1,t2) == t_glb`
413 pub fn check_glb(&self, t1: Ty<'tcx>, t2: Ty<'tcx>, t_glb: Ty<'tcx>) {
414 debug!("check_glb(t1={}, t2={}, t_glb={})", t1, t2, t_glb);
415 match self.glb(t1, t2) {
416 Err(e) => panic!("unexpected error computing LUB: {:?}", e),
417 Ok(InferOk { obligations, value: t }) => {
418 // None of these tests should require nested obligations:
419 assert!(obligations.is_empty());
421 self.assert_eq(t, t_glb);
423 // sanity check for good measure:
424 self.assert_subtype(t, t1);
425 self.assert_subtype(t, t2);
432 fn contravariant_region_ptr_ok() {
433 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
434 env.create_simple_region_hierarchy();
435 let t_rptr1 = env.t_rptr_scope(1);
436 let t_rptr10 = env.t_rptr_scope(10);
437 env.assert_eq(t_rptr1, t_rptr1);
438 env.assert_eq(t_rptr10, t_rptr10);
439 env.make_subtype(t_rptr1, t_rptr10);
444 fn contravariant_region_ptr_err() {
445 test_env(EMPTY_SOURCE_STR, errors(&["mismatched types"]), |env| {
446 env.create_simple_region_hierarchy();
447 let t_rptr1 = env.t_rptr_scope(1);
448 let t_rptr10 = env.t_rptr_scope(10);
449 env.assert_eq(t_rptr1, t_rptr1);
450 env.assert_eq(t_rptr10, t_rptr10);
452 // will cause an error when regions are resolved
453 env.make_subtype(t_rptr10, t_rptr1);
458 fn sub_free_bound_false() {
461 //! fn(&'a isize) <: for<'b> fn(&'b isize)
465 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
466 env.create_simple_region_hierarchy();
467 let t_rptr_free1 = env.t_rptr_free(1, 1);
468 let t_rptr_bound1 = env.t_rptr_late_bound(1);
469 env.check_not_sub(env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
470 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
475 fn sub_bound_free_true() {
478 //! for<'a> fn(&'a isize) <: fn(&'b isize)
482 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
483 env.create_simple_region_hierarchy();
484 let t_rptr_bound1 = env.t_rptr_late_bound(1);
485 let t_rptr_free1 = env.t_rptr_free(1, 1);
486 env.check_sub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
487 env.t_fn(&[t_rptr_free1], env.tcx().types.isize));
492 fn sub_free_bound_false_infer() {
495 //! fn(_#1) <: for<'b> fn(&'b isize)
497 //! does NOT hold for any instantiation of `_#1`.
499 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
500 let t_infer1 = env.infcx.next_ty_var(TypeVariableOrigin::MiscVariable(DUMMY_SP));
501 let t_rptr_bound1 = env.t_rptr_late_bound(1);
502 env.check_not_sub(env.t_fn(&[t_infer1], env.tcx().types.isize),
503 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
508 fn lub_free_bound_infer() {
511 //! LUB(fn(_#1), for<'b> fn(&'b isize))
513 //! This should yield `fn(&'_ isize)`. We check
514 //! that it yields `fn(&'x isize)` for some free `'x`,
517 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
518 env.create_simple_region_hierarchy();
519 let t_infer1 = env.infcx.next_ty_var(TypeVariableOrigin::MiscVariable(DUMMY_SP));
520 let t_rptr_bound1 = env.t_rptr_late_bound(1);
521 let t_rptr_free1 = env.t_rptr_free(1, 1);
522 env.check_lub(env.t_fn(&[t_infer1], env.tcx().types.isize),
523 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
524 env.t_fn(&[t_rptr_free1], env.tcx().types.isize));
529 fn lub_bound_bound() {
530 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
531 let t_rptr_bound1 = env.t_rptr_late_bound(1);
532 let t_rptr_bound2 = env.t_rptr_late_bound(2);
533 env.check_lub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
534 env.t_fn(&[t_rptr_bound2], env.tcx().types.isize),
535 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
540 fn lub_bound_free() {
541 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
542 env.create_simple_region_hierarchy();
543 let t_rptr_bound1 = env.t_rptr_late_bound(1);
544 let t_rptr_free1 = env.t_rptr_free(1, 1);
545 env.check_lub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
546 env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
547 env.t_fn(&[t_rptr_free1], env.tcx().types.isize));
552 fn lub_bound_static() {
553 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
554 let t_rptr_bound1 = env.t_rptr_late_bound(1);
555 let t_rptr_static = env.t_rptr_static();
556 env.check_lub(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
557 env.t_fn(&[t_rptr_static], env.tcx().types.isize),
558 env.t_fn(&[t_rptr_static], env.tcx().types.isize));
563 fn lub_bound_bound_inverse_order() {
564 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
565 let t_rptr_bound1 = env.t_rptr_late_bound(1);
566 let t_rptr_bound2 = env.t_rptr_late_bound(2);
567 env.check_lub(env.t_fn(&[t_rptr_bound1, t_rptr_bound2], t_rptr_bound1),
568 env.t_fn(&[t_rptr_bound2, t_rptr_bound1], t_rptr_bound1),
569 env.t_fn(&[t_rptr_bound1, t_rptr_bound1], t_rptr_bound1));
575 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
576 env.create_simple_region_hierarchy();
577 let t_rptr_free1 = env.t_rptr_free(1, 1);
578 let t_rptr_free2 = env.t_rptr_free(1, 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));
587 fn lub_returning_scope() {
588 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
589 env.create_simple_region_hierarchy();
590 let t_rptr_scope10 = env.t_rptr_scope(10);
591 let t_rptr_scope11 = env.t_rptr_scope(11);
592 let t_rptr_empty = env.t_rptr_empty();
593 env.check_lub(env.t_fn(&[t_rptr_scope10], env.tcx().types.isize),
594 env.t_fn(&[t_rptr_scope11], env.tcx().types.isize),
595 env.t_fn(&[t_rptr_empty], env.tcx().types.isize));
600 fn glb_free_free_with_common_scope() {
601 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
602 env.create_simple_region_hierarchy();
603 let t_rptr_free1 = env.t_rptr_free(1, 1);
604 let t_rptr_free2 = env.t_rptr_free(1, 2);
605 let t_rptr_scope = env.t_rptr_scope(1);
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));
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));
624 fn glb_bound_free() {
625 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
626 env.create_simple_region_hierarchy();
627 let t_rptr_bound1 = env.t_rptr_late_bound(1);
628 let t_rptr_free1 = env.t_rptr_free(1, 1);
629 env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
630 env.t_fn(&[t_rptr_free1], env.tcx().types.isize),
631 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
636 fn glb_bound_free_infer() {
637 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
638 let t_rptr_bound1 = env.t_rptr_late_bound(1);
639 let t_infer1 = env.infcx.next_ty_var(TypeVariableOrigin::MiscVariable(DUMMY_SP));
641 // compute GLB(fn(_) -> isize, for<'b> fn(&'b isize) -> isize),
642 // which should yield for<'b> fn(&'b isize) -> isize
643 env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
644 env.t_fn(&[t_infer1], env.tcx().types.isize),
645 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
647 // as a side-effect, computing GLB should unify `_` with
649 let t_resolve1 = env.infcx.shallow_resolve(t_infer1);
650 match t_resolve1.sty {
653 panic!("t_resolve1={:?}", t_resolve1);
660 fn glb_bound_static() {
661 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
662 let t_rptr_bound1 = env.t_rptr_late_bound(1);
663 let t_rptr_static = env.t_rptr_static();
664 env.check_glb(env.t_fn(&[t_rptr_bound1], env.tcx().types.isize),
665 env.t_fn(&[t_rptr_static], env.tcx().types.isize),
666 env.t_fn(&[t_rptr_bound1], env.tcx().types.isize));
670 /// Test substituting a bound region into a function, which introduces another level of binding.
671 /// This requires adjusting the Debruijn index.
673 fn subst_ty_renumber_bound() {
675 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
677 // Theta = [A -> &'a foo]
679 let t_rptr_bound1 = env.t_rptr_late_bound(1);
683 let t_param = env.t_param(0);
684 env.t_fn(&[t_param], env.t_nil())
687 let substs = env.infcx.tcx.intern_substs(&[Kind::from(t_rptr_bound1)]);
688 let t_substituted = t_source.subst(env.infcx.tcx, substs);
690 // t_expected = fn(&'a isize)
692 let t_ptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
693 env.t_fn(&[t_ptr_bound2], env.t_nil())
696 debug!("subst_bound: t_source={:?} substs={:?} t_substituted={:?} t_expected={:?}",
702 assert_eq!(t_substituted, t_expected);
706 /// Test substituting a bound region into a function, which introduces another level of binding.
707 /// This requires adjusting the Debruijn index.
709 fn subst_ty_renumber_some_bounds() {
710 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
712 // Theta = [A -> &'a foo]
714 let t_rptr_bound1 = env.t_rptr_late_bound(1);
716 // t_source = (A, fn(A))
718 let t_param = env.t_param(0);
719 env.t_pair(t_param, env.t_fn(&[t_param], env.t_nil()))
722 let substs = env.infcx.tcx.intern_substs(&[Kind::from(t_rptr_bound1)]);
723 let t_substituted = t_source.subst(env.infcx.tcx, substs);
725 // t_expected = (&'a isize, fn(&'a isize))
727 // but not that the Debruijn index is different in the different cases.
729 let t_rptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
730 env.t_pair(t_rptr_bound1, env.t_fn(&[t_rptr_bound2], env.t_nil()))
733 debug!("subst_bound: t_source={:?} substs={:?} t_substituted={:?} t_expected={:?}",
739 assert_eq!(t_substituted, t_expected);
743 /// Test that we correctly compute whether a type has escaping regions or not.
747 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
749 // Theta = [A -> &'a foo]
750 env.create_simple_region_hierarchy();
752 assert!(!env.t_nil().has_escaping_regions());
754 let t_rptr_free1 = env.t_rptr_free(1, 1);
755 assert!(!t_rptr_free1.has_escaping_regions());
757 let t_rptr_bound1 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(1));
758 assert!(t_rptr_bound1.has_escaping_regions());
760 let t_rptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
761 assert!(t_rptr_bound2.has_escaping_regions());
764 let t_param = env.t_param(0);
765 assert!(!t_param.has_escaping_regions());
766 let t_fn = env.t_fn(&[t_param], env.t_nil());
767 assert!(!t_fn.has_escaping_regions());
771 /// Test applying a substitution where the value being substituted for an early-bound region is a
772 /// late-bound region.
774 fn subst_region_renumber_region() {
775 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
776 let re_bound1 = env.re_late_bound_with_debruijn(1, ty::DebruijnIndex::new(1));
778 // type t_source<'a> = fn(&'a isize)
780 let re_early = env.re_early_bound(0, "'a");
781 env.t_fn(&[env.t_rptr(re_early)], env.t_nil())
784 let substs = env.infcx.tcx.intern_substs(&[Kind::from(re_bound1)]);
785 let t_substituted = t_source.subst(env.infcx.tcx, substs);
787 // t_expected = fn(&'a isize)
789 // but not that the Debruijn index is different in the different cases.
791 let t_rptr_bound2 = env.t_rptr_late_bound_with_debruijn(1, ty::DebruijnIndex::new(2));
792 env.t_fn(&[t_rptr_bound2], env.t_nil())
795 debug!("subst_bound: t_source={:?} substs={:?} t_substituted={:?} t_expected={:?}",
801 assert_eq!(t_substituted, t_expected);
807 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
808 let tcx = env.infcx.tcx;
809 let int_ty = tcx.types.isize;
810 let uint_ty = tcx.types.usize;
811 let tup1_ty = tcx.intern_tup(&[int_ty, uint_ty, int_ty, uint_ty], false);
812 let tup2_ty = tcx.intern_tup(&[tup1_ty, tup1_ty, uint_ty], false);
813 let walked: Vec<_> = tup2_ty.walk().collect();
815 [tup2_ty, tup1_ty, int_ty, uint_ty, int_ty, uint_ty, tup1_ty, int_ty,
816 uint_ty, int_ty, uint_ty, uint_ty]);
821 fn walk_ty_skip_subtree() {
822 test_env(EMPTY_SOURCE_STR, errors(&[]), |env| {
823 let tcx = env.infcx.tcx;
824 let int_ty = tcx.types.isize;
825 let uint_ty = tcx.types.usize;
826 let tup1_ty = tcx.intern_tup(&[int_ty, uint_ty, int_ty, uint_ty], false);
827 let tup2_ty = tcx.intern_tup(&[tup1_ty, tup1_ty, uint_ty], false);
829 // types we expect to see (in order), plus a boolean saying
830 // whether to skip the subtree.
831 let mut expected = vec![(tup2_ty, false),
837 (tup1_ty, true), // skip the isize/usize/isize/usize
841 let mut walker = tup2_ty.walk();
842 while let Some(t) = walker.next() {
843 debug!("walked to {:?}", t);
844 let (expected_ty, skip) = expected.pop().unwrap();
845 assert_eq!(t, expected_ty);
847 walker.skip_current_subtree();
851 assert!(expected.is_empty());