orig_params,
trait_pred.to_poly_trait_predicate(),
));
+
match result {
Ok(Some(Vtable::VtableImpl(_))) => {
debug!(
manual impl found, bailing out",
did, trait_did, generics
);
- return true;
+ true
}
- _ => return false,
- };
+ _ => false
+ }
});
// If an explicit impl exists, it always takes priority over an auto impl
if new_trait.def_id() == old_trait.def_id() {
let new_substs = new_trait.skip_binder().trait_ref.substs;
let old_substs = old_trait.skip_binder().trait_ref.substs;
+
if !new_substs.types().eq(old_substs.types()) {
// We can't compare lifetimes if the types are different,
// so skip checking old_pred
pub fn get_lifetime(&self, region: Region, names_map: &FxHashMap<String, String>) -> String {
self.region_name(region)
- .map(|name| {
- names_map.get(&name).unwrap_or_else(|| {
+ .map(|name|
+ names_map.get(&name).unwrap_or_else(||
panic!("Missing lifetime with name {:?} for {:?}", name, region)
- })
- })
- .unwrap_or(&"'static".to_string())
+ )
+ )
+ .unwrap_or(&"'static".to_owned())
.clone()
}
let trait_ref = ty.erase_regions(&trait_ref);
debug!("codegen_fulfill_obligation(trait_ref={:?}, def_id={:?})",
- (param_env, trait_ref), trait_ref.def_id());
+ (param_env, trait_ref), trait_ref.def_id());
// Do the initial selection for the obligation. This yields the
// shallow result we are looking for -- that is, what specific impl.
let obligation_cause = ObligationCause::dummy();
let obligation = Obligation::new(obligation_cause,
- param_env,
- trait_ref.to_poly_trait_predicate());
+ param_env,
+ trait_ref.to_poly_trait_predicate());
let selection = match selcx.select(&obligation) {
Ok(Some(selection)) => selection,
// overflow bug, since I believe this is the only case
// where ambiguity can result.
bug!("Encountered ambiguity selecting `{:?}` during codegen, \
- presuming due to overflow",
- trait_ref)
+ presuming due to overflow",
+ trait_ref)
}
Err(e) => {
- bug!("Encountered error `{:?}` selecting `{:?}` during codegen",
- e, trait_ref)
+ bug!("Encountered error `{:?}` selecting `{:?}` during codegen", e, trait_ref)
}
};
// In principle, we only need to do this so long as `result`
// contains unbound type parameters. It could be a slight
// optimization to stop iterating early.
- match fulfill_cx.select_all_or_error(self) {
- Ok(()) => { }
- Err(errors) => {
- span_bug!(span, "Encountered errors `{:?}` resolving bounds after type-checking",
- errors);
- }
+ if let Err(errors) = fulfill_cx.select_all_or_error(self) {
+ span_bug!(span, "Encountered errors `{:?}` resolving bounds after type-checking",
+ errors);
}
let result = self.resolve_type_vars_if_possible(result);
let result = self.tcx.erase_regions(&result);
- match self.tcx.lift_to_global(&result) {
- Some(result) => result,
- None => {
- span_bug!(span, "Uninferred types/regions in `{:?}`", result);
- }
- }
+ self.tcx.lift_to_global(&result).unwrap_or_else(||
+ span_bug!(span, "Uninferred types/regions in `{:?}`", result)
+ )
}
}
b_def_id: DefId)
-> Option<OverlapResult<'tcx>>
{
- debug!("overlap(a_def_id={:?}, b_def_id={:?})",
- a_def_id,
- b_def_id);
+ debug!("overlap(a_def_id={:?}, b_def_id={:?})", a_def_id, b_def_id);
// For the purposes of this check, we don't bring any skolemized
// types into scope; instead, we replace the generic types with
// Do `a` and `b` unify? If not, no overlap.
let obligations = match selcx.infcx().at(&ObligationCause::dummy(), param_env)
- .eq_impl_headers(&a_impl_header, &b_impl_header) {
- Ok(InferOk { obligations, value: () }) => {
- obligations
- }
+ .eq_impl_headers(&a_impl_header, &b_impl_header)
+ {
+ Ok(InferOk { obligations, value: () }) => obligations,
Err(_) => return None
};
return None
}
- let impl_header = selcx.infcx().resolve_type_vars_if_possible(&a_impl_header);
+ let impl_header = selcx.infcx().resolve_type_vars_if_possible(&a_impl_header);
let intercrate_ambiguity_causes = selcx.take_intercrate_ambiguity_causes();
debug!("overlap: intercrate_ambiguity_causes={:#?}", intercrate_ambiguity_causes);
Some(OverlapResult { impl_header, intercrate_ambiguity_causes })
ty::Foreign(did) => def_id_is_local(did, in_crate),
ty::Dynamic(ref tt, ..) => {
- tt.principal().map_or(false, |p| {
+ tt.principal().map_or(false, |p|
def_id_is_local(p.def_id(), in_crate)
- })
+ )
}
- ty::Error => {
- true
- }
+ ty::Error => true,
ty::Closure(..) |
ty::Generator(..) |
use infer::{self, InferCtxt};
use infer::type_variable::TypeVariableOrigin;
use std::fmt;
+use std::iter;
use syntax::ast;
use session::DiagnosticMessageId;
use ty::{self, AdtKind, ToPredicate, ToPolyTraitRef, Ty, TyCtxt, TypeFoldable};
index: Option<usize>, // None if this is an old error
}
- let mut error_map : FxHashMap<_, Vec<_>> =
+ let mut error_map: FxHashMap<_, Vec<_>> =
self.reported_trait_errors.borrow().iter().map(|(&span, predicates)| {
(span, predicates.iter().map(|predicate| ErrorDescriptor {
predicate: predicate.clone(),
// We do this in 2 passes because we want to display errors in order, tho
// maybe it *is* better to sort errors by span or something.
- let mut is_suppressed: Vec<bool> = errors.iter().map(|_| false).collect();
+ let mut is_suppressed = vec![false; errors.len()];
for (_, error_set) in error_map.iter() {
// We want to suppress "duplicate" errors with the same span.
for error in error_set {
_ => {
// this is a "direct", user-specified, rather than derived,
// obligation.
- flags.push(("direct".to_string(), None));
+ flags.push(("direct".to_owned(), None));
}
}
// Currently I'm leaving it for what I need for `try`.
if self.tcx.trait_of_item(item) == Some(trait_ref.def_id) {
let method = self.tcx.item_name(item);
- flags.push(("from_method".to_string(), None));
- flags.push(("from_method".to_string(), Some(method.to_string())));
+ flags.push(("from_method".to_owned(), None));
+ flags.push(("from_method".to_owned(), Some(method.to_string())));
}
}
if let Some(k) = obligation.cause.span.compiler_desugaring_kind() {
- flags.push(("from_desugaring".to_string(), None));
- flags.push(("from_desugaring".to_string(), Some(k.name().to_string())));
+ flags.push(("from_desugaring".to_owned(), None));
+ flags.push(("from_desugaring".to_owned(), Some(k.name().to_string())));
}
let generics = self.tcx.generics_of(def_id);
let self_ty = trait_ref.self_ty();
// This is also included through the generics list as `Self`,
// but the parser won't allow you to use it
- flags.push(("_Self".to_string(), Some(self_ty.to_string())));
+ flags.push(("_Self".to_owned(), Some(self_ty.to_string())));
if let Some(def) = self_ty.ty_adt_def() {
// We also want to be able to select self's original
// signature with no type arguments resolved
- flags.push(("_Self".to_string(), Some(self.tcx.type_of(def.did).to_string())));
+ flags.push(("_Self".to_owned(), Some(self.tcx.type_of(def.did).to_string())));
}
for param in generics.params.iter() {
}
if let Some(true) = self_ty.ty_adt_def().map(|def| def.did.is_local()) {
- flags.push(("crate_local".to_string(), None));
+ flags.push(("crate_local".to_owned(), None));
}
if let Ok(Some(command)) = OnUnimplementedDirective::of_item(
let simp = fast_reject::simplify_type(self.tcx,
trait_ref.skip_binder().self_ty(),
true);
- let mut impl_candidates = Vec::new();
+ let all_impls = self.tcx.all_impls(trait_ref.def_id());
match simp {
- Some(simp) => self.tcx.for_each_impl(trait_ref.def_id(), |def_id| {
+ Some(simp) => all_impls.iter().filter_map(|&def_id| {
let imp = self.tcx.impl_trait_ref(def_id).unwrap();
let imp_simp = fast_reject::simplify_type(self.tcx,
imp.self_ty(),
true);
if let Some(imp_simp) = imp_simp {
if simp != imp_simp {
- return;
+ return None
}
}
- impl_candidates.push(imp);
- }),
- None => self.tcx.for_each_impl(trait_ref.def_id(), |def_id| {
- impl_candidates.push(
- self.tcx.impl_trait_ref(def_id).unwrap());
- })
- };
- impl_candidates
+
+ Some(imp)
+ }).collect(),
+ None => all_impls.iter().map(|&def_id|
+ self.tcx.impl_trait_ref(def_id).unwrap()
+ ).collect()
+ }
}
fn report_similar_impl_candidates(&self,
span,
E0277,
"{}",
- message.unwrap_or_else(|| {
+ message.unwrap_or_else(||
format!("the trait bound `{}` is not satisfied{}",
trait_ref.to_predicate(), post_message)
- }));
+ ));
let explanation =
if obligation.cause.code == ObligationCauseCode::MainFunctionType {
// "the type `T` can't be frobnicated"
// which is somewhat confusing.
err.help(&format!("consider adding a `where {}` bound",
- trait_ref.to_predicate()));
+ trait_ref.to_predicate()));
} else if !have_alt_message {
// Can't show anything else useful, try to find similar impls.
let impl_candidates = self.find_similar_impl_candidates(trait_ref);
ty::Predicate::RegionOutlives(ref predicate) => {
let predicate = self.resolve_type_vars_if_possible(predicate);
let err = self.region_outlives_predicate(&obligation.cause,
- &predicate).err().unwrap();
+ &predicate).err().unwrap();
struct_span_err!(self.tcx.sess, span, E0279,
"the requirement `{}` is not satisfied (`{}`)",
predicate, err)
let mut err = struct_span_err!(
self.tcx.sess, closure_span, E0525,
"expected a closure that implements the `{}` trait, \
- but this closure only implements `{}`",
+ but this closure only implements `{}`",
kind,
found_kind);
OutputTypeParameterMismatch(ref found_trait_ref, ref expected_trait_ref, _) => {
let found_trait_ref = self.resolve_type_vars_if_possible(&*found_trait_ref);
let expected_trait_ref = self.resolve_type_vars_if_possible(&*expected_trait_ref);
+
if expected_trait_ref.self_ty().references_error() {
return;
}
+
let found_trait_ty = found_trait_ref.self_ty();
let found_did = match found_trait_ty.sty {
- ty::Closure(did, _) |
- ty::Foreign(did) |
- ty::FnDef(did, _) => Some(did),
+ ty::Closure(did, _) | ty::Foreign(did) | ty::FnDef(did, _) => Some(did),
ty::Adt(def, _) => Some(def.did),
_ => None,
};
- let found_span = found_did.and_then(|did| {
+
+ let found_span = found_did.and_then(|did|
self.tcx.hir.span_if_local(did)
- }).map(|sp| self.tcx.sess.source_map().def_span(sp)); // the sp could be an fn def
+ ).map(|sp| self.tcx.sess.source_map().def_span(sp)); // the sp could be an fn def
let found = match found_trait_ref.skip_binder().substs.type_at(1).sty {
- ty::Tuple(ref tys) => tys.iter()
- .map(|_| ArgKind::empty()).collect::<Vec<_>>(),
+ ty::Tuple(ref tys) => vec![ArgKind::empty(); tys.len()],
_ => vec![ArgKind::empty()],
};
+
let expected = match expected_trait_ref.skip_binder().substs.type_at(1).sty {
ty::Tuple(ref tys) => tys.iter()
- .map(|t| match t.sty {
- ty::Tuple(ref tys) => ArgKind::Tuple(
- Some(span),
- tys.iter()
- .map(|ty| ("_".to_owned(), ty.sty.to_string()))
- .collect::<Vec<_>>()
- ),
- _ => ArgKind::Arg("_".to_owned(), t.sty.to_string()),
- }).collect(),
+ .map(|t| ArgKind::from_expected_ty(t, Some(span))).collect(),
ref sty => vec![ArgKind::Arg("_".to_owned(), sty.to_string())],
};
+
if found.len() == expected.len() {
self.report_closure_arg_mismatch(span,
found_span,
TraitNotObjectSafe(did) => {
let violations = self.tcx.object_safety_violations(did);
- self.tcx.report_object_safety_error(span, did,
- violations)
+ self.tcx.report_object_safety_error(span, did, violations)
}
ConstEvalFailure(ref err) => {
.map(|arg| match arg.clone().node {
hir::TyKind::Tup(ref tys) => ArgKind::Tuple(
Some(arg.span),
- tys.iter()
- .map(|_| ("_".to_owned(), "_".to_owned()))
- .collect::<Vec<_>>(),
+ vec![("_".to_owned(), "_".to_owned()); tys.len()]
),
- _ => ArgKind::Arg("_".to_owned(), "_".to_owned())
+ _ => ArgKind::empty()
}).collect::<Vec<ArgKind>>())
}
Node::Variant(&hir::Variant {
..
}) => {
(self.tcx.sess.source_map().def_span(span),
- fields.iter().map(|field| {
+ fields.iter().map(|field|
ArgKind::Arg(field.ident.to_string(), "_".to_string())
- }).collect::<Vec<_>>())
+ ).collect::<Vec<_>>())
}
Node::StructCtor(ref variant_data) => {
(self.tcx.sess.source_map().def_span(self.tcx.hir.span(variant_data.id())),
- variant_data.fields()
- .iter().map(|_| ArgKind::Arg("_".to_owned(), "_".to_owned()))
- .collect())
+ vec![ArgKind::empty(); variant_data.fields().len()])
}
_ => panic!("non-FnLike node found: {:?}", node),
}
found_str,
);
- err.span_label(span, format!( "expected {} that takes {}", kind, expected_str));
+ err.span_label(span, format!("expected {} that takes {}", kind, expected_str));
if let Some(found_span) = found_span {
err.span_label(found_span, format!("takes {}", found_str));
// found arguments is empty (assume the user just wants to ignore args in this case).
// For example, if `expected_args_length` is 2, suggest `|_, _|`.
if found_args.is_empty() && is_closure {
- let underscores = "_".repeat(expected_args.len())
- .split("")
- .filter(|s| !s.is_empty())
+ let underscores = iter::repeat("_")
+ .take(expected_args.len())
.collect::<Vec<_>>()
.join(", ");
err.span_suggestion_with_applicability(
if fields.len() == expected_args.len() {
let sugg = fields.iter()
.map(|(name, _)| name.to_owned())
- .collect::<Vec<String>>().join(", ");
+ .collect::<Vec<String>>()
+ .join(", ");
err.span_suggestion_with_applicability(found_span,
"change the closure to take multiple \
arguments instead of a single tuple",
let inputs = trait_ref.substs.type_at(1);
let sig = if let ty::Tuple(inputs) = inputs.sty {
tcx.mk_fn_sig(
- inputs.iter().map(|&x| x),
+ inputs.iter().cloned(),
tcx.mk_infer(ty::TyVar(ty::TyVid { index: 0 })),
false,
hir::Unsafety::Normal,
let mut reported_violations = FxHashSet();
for violation in violations {
- if !reported_violations.insert(violation.clone()) {
- continue;
+ if reported_violations.insert(violation.clone()) {
+ err.note(&violation.error_msg());
}
- err.note(&violation.error_msg());
}
err
}
self.need_type_info_err(body_id, span, self_ty).emit();
} else {
let mut err = struct_span_err!(self.tcx.sess,
- span, E0283,
- "type annotations required: \
+ span, E0283,
+ "type annotations required: \
cannot resolve `{}`",
- predicate);
+ predicate);
self.note_obligation_cause(&mut err, obligation);
err.emit();
}
ObligationCauseCode::ItemObligation(item_def_id) => {
let item_name = tcx.item_path_str(item_def_id);
let msg = format!("required by `{}`", item_name);
+
if let Some(sp) = tcx.hir.span_if_local(item_def_id) {
let sp = tcx.sess.source_map().def_span(sp);
err.span_note(sp, &msg);
parent_trait_ref.skip_binder().self_ty()));
let parent_predicate = parent_trait_ref.to_predicate();
self.note_obligation_cause_code(err,
- &parent_predicate,
- &data.parent_code,
- obligated_types);
+ &parent_predicate,
+ &data.parent_code,
+ obligated_types);
}
ObligationCauseCode::CompareImplMethodObligation { .. } => {
err.note(
}
fn is_recursive_obligation(&self,
- obligated_types: &mut Vec<&ty::TyS<'tcx>>,
- cause_code: &ObligationCauseCode<'tcx>) -> bool {
+ obligated_types: &mut Vec<&ty::TyS<'tcx>>,
+ cause_code: &ObligationCauseCode<'tcx>) -> bool {
if let ObligationCauseCode::BuiltinDerivedObligation(ref data) = cause_code {
let parent_trait_ref = self.resolve_type_vars_if_possible(&data.parent_trait_ref);
- for obligated_type in obligated_types {
- if obligated_type == &parent_trait_ref.skip_binder().self_ty() {
- return true;
- }
+
+ if obligated_types.iter().any(|ot| ot == &parent_trait_ref.skip_binder().self_ty()) {
+ return true;
}
}
- return false;
+ false
}
}
/// Summarizes information
+#[derive(Clone)]
pub enum ArgKind {
/// An argument of non-tuple type. Parameters are (name, ty)
Arg(String, String),
}
/// Creates an `ArgKind` from the expected type of an
- /// argument. This has no name (`_`) and no source spans..
- pub fn from_expected_ty(t: Ty<'_>) -> ArgKind {
+ /// argument. It has no name (`_`) and an optional source span.
+ pub fn from_expected_ty(t: Ty<'_>, span: Option<Span>) -> ArgKind {
match t.sty {
ty::Tuple(ref tys) => ArgKind::Tuple(
- None,
+ span,
tys.iter()
.map(|ty| ("_".to_owned(), ty.sty.to_string()))
.collect::<Vec<_>>()
if self.selcx.coinductive_match(cycle.clone().map(|s| s.obligation.predicate)) {
debug!("process_child_obligations: coinductive match");
} else {
- let cycle : Vec<_> = cycle.map(|c| c.obligation.clone()).collect();
+ let cycle: Vec<_> = cycle.map(|c| c.obligation.clone()).collect();
self.selcx.infcx().report_overflow_error_cycle(&cycle);
}
}
let predicates: Vec<_> =
util::elaborate_predicates(tcx, unnormalized_env.caller_bounds.to_vec())
- .collect();
+ .collect();
debug!("normalize_param_env_or_error: elaborated-predicates={:?}",
predicates);
};
debug!("normalize_param_env_or_error: normalized predicates={:?}",
- predicates);
+ predicates);
let region_scope_tree = region::ScopeTree::default();
// the method may have some early-bound lifetimes, add
// regions for those
- let substs = trait_ref.map_bound(|trait_ref| {
- Substs::for_item(tcx, def_id, |param, _| {
+ let substs = trait_ref.map_bound(|trait_ref|
+ Substs::for_item(tcx, def_id, |param, _|
match param.kind {
GenericParamDefKind::Lifetime => tcx.types.re_erased.into(),
GenericParamDefKind::Type {..} => {
trait_ref.substs[param.index as usize]
}
}
- })
- });
+ )
+ );
// the trait type may have higher-ranked lifetimes in it;
// so erase them if they appear, so that we get the type
// Check methods for violations.
let mut violations: Vec<_> = self.associated_items(trait_def_id)
.filter(|item| item.kind == ty::AssociatedKind::Method)
- .filter_map(|item| {
+ .filter_map(|item|
self.object_safety_violation_for_method(trait_def_id, &item)
.map(|code| ObjectSafetyViolation::Method(item.ident.name, code))
- }).filter(|violation| {
+ ).filter(|violation| {
if let ObjectSafetyViolation::Method(_,
- MethodViolationCode::WhereClauseReferencesSelf(span)) = violation {
- // Using`CRATE_NODE_ID` is wrong, but it's hard to get a more precise id.
+ MethodViolationCode::WhereClauseReferencesSelf(span)) = violation
+ {
+ // Using `CRATE_NODE_ID` is wrong, but it's hard to get a more precise id.
// It's also hard to get a use site span, so we use the method definition span.
self.lint_node_note(
lint::builtin::WHERE_CLAUSES_OBJECT_SAFETY,
ast::CRATE_NODE_ID,
*span,
&format!("the trait `{}` cannot be made into an object",
- self.item_path_str(trait_def_id)),
+ self.item_path_str(trait_def_id)),
&violation.error_msg());
false
} else {
let predicates = self.predicates_of(def_id);
let predicates = predicates.instantiate_identity(self).predicates;
elaborate_predicates(self, predicates)
- .any(|predicate| {
- match predicate {
- ty::Predicate::Trait(ref trait_pred) if trait_pred.def_id() == sized_def_id => {
- trait_pred.skip_binder().self_ty().is_self()
- }
- ty::Predicate::Projection(..) |
- ty::Predicate::Trait(..) |
- ty::Predicate::Subtype(..) |
- ty::Predicate::RegionOutlives(..) |
- ty::Predicate::WellFormed(..) |
- ty::Predicate::ObjectSafe(..) |
- ty::Predicate::ClosureKind(..) |
- ty::Predicate::TypeOutlives(..) |
- ty::Predicate::ConstEvaluatable(..) => {
- false
- }
+ .any(|predicate| match predicate {
+ ty::Predicate::Trait(ref trait_pred) if trait_pred.def_id() == sized_def_id => {
+ trait_pred.skip_binder().self_ty().is_self()
}
- })
+ ty::Predicate::Projection(..) |
+ ty::Predicate::Trait(..) |
+ ty::Predicate::Subtype(..) |
+ ty::Predicate::RegionOutlives(..) |
+ ty::Predicate::WellFormed(..) |
+ ty::Predicate::ObjectSafe(..) |
+ ty::Predicate::ClosureKind(..) |
+ ty::Predicate::TypeOutlives(..) |
+ ty::Predicate::ConstEvaluatable(..) => {
+ false
+ }
+ }
+ )
}
/// Returns `Some(_)` if this method makes the containing trait not object safe.
let condition = if is_root {
None
} else {
- let cond = item_iter.next().ok_or_else(|| {
+ let cond = item_iter.next().ok_or_else(||
parse_error(tcx, span,
"empty `on`-clause in `#[rustc_on_unimplemented]`",
"empty on-clause here",
None)
- })?.meta_item().ok_or_else(|| {
+ )?.meta_item().ok_or_else(||
parse_error(tcx, span,
"invalid `on`-clause in `#[rustc_on_unimplemented]`",
"invalid on-clause here",
None)
- })?;
+ )?;
attr::eval_condition(cond, &tcx.sess.parse_sess, &mut |_| true);
Some(cond.clone())
};
// `{from_desugaring}` is allowed
Position::ArgumentNamed(s) if s == "from_desugaring" => (),
// So is `{A}` if A is a type parameter
- Position::ArgumentNamed(s) => match generics.params.iter().find(|param| {
+ Position::ArgumentNamed(s) => match generics.params.iter().find(|param|
param.name == s
- }) {
+ ) {
Some(_) => (),
None => {
span_err!(tcx.sess, span, E0230,
let empty_string = String::new();
let parser = Parser::new(&self.0, None);
- parser.map(|p| {
+ parser.map(|p|
match p {
Piece::String(s) => s,
Piece::NextArgument(a) => match a.position {
}
}
},
- _ => {
- bug!("broken on_unimplemented {:?} - bad format arg", self.0)
- }
+ _ => bug!("broken on_unimplemented {:?} - bad format arg", self.0)
}
}
- }).collect()
+ ).collect()
}
}
match (current, candidate) {
(ParamEnv(..), ParamEnv(..)) => convert_to_ambiguous = (),
(ParamEnv(..), _) => return false,
- (_, ParamEnv(..)) => { unreachable!(); }
+ (_, ParamEnv(..)) => unreachable!(),
(_, _) => convert_to_ambiguous = (),
}
}
normalized_ty
}
- _ => {
- ty
- }
+ _ => ty
}
}
instance,
promoted: None
};
- match tcx.const_eval(param_env.and(cid)) {
- Ok(evaluated) => {
- let evaluated = evaluated.subst(self.tcx(), substs);
- return self.fold_const(evaluated);
- }
- Err(_) => {}
+ if let Ok(evaluated) = tcx.const_eval(param_env.and(cid)) {
+ let evaluated = evaluated.subst(self.tcx(), substs);
+ return self.fold_const(evaluated);
}
}
} else {
instance,
promoted: None
};
- match tcx.const_eval(param_env.and(cid)) {
- Ok(evaluated) => return self.fold_const(evaluated),
- Err(_) => {}
+ if let Ok(evaluated) = tcx.const_eval(param_env.and(cid)) {
+ return self.fold_const(evaluated)
}
}
}
candidate_set.mark_ambiguous();
return;
}
- _ => { return; }
+ _ => return
};
// If so, extract what we know from the trait and try to come up with a good answer.
for predicate in env_predicates {
debug!("assemble_candidates_from_predicates: predicate={:?}",
predicate);
- match predicate {
- ty::Predicate::Projection(data) => {
- let same_def_id = data.projection_def_id() == obligation.predicate.item_def_id;
-
- let is_match = same_def_id && infcx.probe(|_| {
- let data_poly_trait_ref =
- data.to_poly_trait_ref(infcx.tcx);
- let obligation_poly_trait_ref =
- obligation_trait_ref.to_poly_trait_ref();
- infcx.at(&obligation.cause, obligation.param_env)
- .sup(obligation_poly_trait_ref, data_poly_trait_ref)
- .map(|InferOk { obligations: _, value: () }| {
- // FIXME(#32730) -- do we need to take obligations
- // into account in any way? At the moment, no.
- })
- .is_ok()
- });
-
- debug!("assemble_candidates_from_predicates: candidate={:?} \
- is_match={} same_def_id={}",
- data, is_match, same_def_id);
-
- if is_match {
- candidate_set.push_candidate(ctor(data));
- }
+ if let ty::Predicate::Projection(data) = predicate {
+ let same_def_id = data.projection_def_id() == obligation.predicate.item_def_id;
+
+ let is_match = same_def_id && infcx.probe(|_| {
+ let data_poly_trait_ref =
+ data.to_poly_trait_ref(infcx.tcx);
+ let obligation_poly_trait_ref =
+ obligation_trait_ref.to_poly_trait_ref();
+ infcx.at(&obligation.cause, obligation.param_env)
+ .sup(obligation_poly_trait_ref, data_poly_trait_ref)
+ .map(|InferOk { obligations: _, value: () }| {
+ // FIXME(#32730) -- do we need to take obligations
+ // into account in any way? At the moment, no.
+ })
+ .is_ok()
+ });
+
+ debug!("assemble_candidates_from_predicates: candidate={:?} \
+ is_match={} same_def_id={}",
+ data, is_match, same_def_id);
+
+ if is_match {
+ candidate_set.push_candidate(ctor(data));
}
- _ => {}
}
}
}
return Err(());
}
Err(e) => {
- debug!("assemble_candidates_from_impls: selection error {:?}",
- e);
+ debug!("assemble_candidates_from_impls: selection error {:?}", e);
candidate_set.mark_error(e);
return Err(());
}
let mut env_predicates = env_predicates.filter(|data| {
let data_poly_trait_ref = data.to_poly_trait_ref(selcx.tcx());
let obligation_poly_trait_ref = obligation_trait_ref.to_poly_trait_ref();
- selcx.infcx().probe(|_| {
+ selcx.infcx().probe(|_|
selcx.infcx().at(&obligation.cause, obligation.param_env)
.sup(obligation_poly_trait_ref, data_poly_trait_ref)
.is_ok()
- })
+ )
});
// select the first matching one; there really ought to be one or
obligation.predicate.self_ty(),
fn_sig,
flag)
- .map_bound(|(trait_ref, ret_type)| {
+ .map_bound(|(trait_ref, ret_type)|
ty::ProjectionPredicate {
projection_ty: ty::ProjectionTy::from_ref_and_name(
tcx,
),
ty: ret_type
}
- });
+ );
confirm_param_env_candidate(selcx, obligation, predicate)
}
debug!("c_ty = {:?}", c_ty);
match &gcx.dropck_outlives(c_ty) {
Ok(result) if result.is_proven() => {
- match self.infcx.instantiate_query_result_and_region_obligations(
+ if let Ok(InferOk { value, obligations }) =
+ self.infcx.instantiate_query_result_and_region_obligations(
self.cause,
self.param_env,
&orig_values,
- result,
- ) {
- Ok(InferOk { value, obligations }) => {
- let ty = self.infcx.resolve_type_vars_if_possible(&ty);
- let kinds = value.into_kinds_reporting_overflows(tcx, span, ty);
- return InferOk {
- value: kinds,
- obligations,
- };
- }
-
- Err(_) => { /* fallthrough to error-handling code below */ }
+ result)
+ {
+ let ty = self.infcx.resolve_type_vars_if_possible(&ty);
+ let kinds = value.into_kinds_reporting_overflows(tcx, span, ty);
+ return InferOk {
+ value: kinds,
+ obligations,
+ };
}
}
fn from_iter<I: IntoIterator<Item = DtorckConstraint<'tcx>>>(iter: I) -> Self {
let mut result = Self::empty();
- for DtorckConstraint {
- outlives,
- dtorck_types,
- overflows,
- } in iter
- {
+ for DtorckConstraint { outlives, dtorck_types, overflows } in iter {
result.outlives.extend(outlives);
result.dtorck_types.extend(dtorck_types);
result.overflows.extend(overflows);
}
}
- // The following *might* require a destructor: it would deeper inspection to tell.
+ // The following *might* require a destructor: needs deeper inspection.
ty::Dynamic(..)
| ty::Projection(..)
| ty::Param(_)
value,
self.param_env,
);
+ if !value.has_projections() {
+ return Ok(Normalized {
+ value: value.clone(),
+ obligations: vec![],
+ });
+ }
+
let mut normalizer = QueryNormalizer {
infcx: self.infcx,
cause: self.cause,
error: false,
anon_depth: 0,
};
- if !value.has_projections() {
- return Ok(Normalized {
- value: value.clone(),
- obligations: vec![],
- });
- }
let value1 = value.fold_with(&mut normalizer);
if normalizer.error {
let gcx = self.infcx.tcx.global_tcx();
let mut orig_values = SmallVec::new();
- let c_data = self.infcx
- .canonicalize_query(&self.param_env.and(*data), &mut orig_values);
+ let c_data = self.infcx.canonicalize_query(
+ &self.param_env.and(*data), &mut orig_values);
debug!("QueryNormalizer: c_data = {:#?}", c_data);
debug!("QueryNormalizer: orig_values = {:#?}", orig_values);
match gcx.normalize_projection_ty(c_data) {
self.cause,
self.param_env,
&orig_values,
- &result,
- ) {
- Ok(InferOk {
- value: result,
- obligations,
- }) => {
+ &result)
+ {
+ Ok(InferOk { value: result, obligations }) => {
debug!("QueryNormalizer: result = {:#?}", result);
debug!("QueryNormalizer: obligations = {:#?}", obligations);
self.obligations.extend(obligations);
instance,
promoted: None,
};
- match tcx.const_eval(param_env.and(cid)) {
- Ok(evaluated) => {
- let evaluated = evaluated.subst(self.tcx(), substs);
- return self.fold_const(evaluated);
- }
- Err(_) => {}
+ if let Ok(evaluated) = tcx.const_eval(param_env.and(cid)) {
+ let evaluated = evaluated.subst(self.tcx(), substs);
+ return self.fold_const(evaluated);
}
}
} else {
instance,
promoted: None,
};
- match tcx.const_eval(param_env.and(cid)) {
- Ok(evaluated) => return self.fold_const(evaluated),
- Err(_) => {}
+ if let Ok(evaluated) = tcx.const_eval(param_env.and(cid)) {
+ return self.fold_const(evaluated)
}
}
}
use hir;
use util::nodemap::{FxHashMap, FxHashSet};
-
pub struct SelectionContext<'cx, 'gcx: 'cx+'tcx, 'tcx: 'cx> {
infcx: &'cx InferCtxt<'cx, 'gcx, 'tcx>,
#[derive(Clone)]
pub struct SelectionCache<'tcx> {
hashmap: Lock<FxHashMap<ty::TraitRef<'tcx>,
- WithDepNode<SelectionResult<'tcx, SelectionCandidate<'tcx>>>>>,
+ WithDepNode<SelectionResult<'tcx, SelectionCandidate<'tcx>>>>>,
}
/// The selection process begins by considering all impls, where
obligation: &PredicateObligation<'tcx>)
-> Result<EvaluationResult, OverflowError>
{
- self.probe(|this, _| {
+ self.probe(|this, _|
this.evaluate_predicate_recursively(TraitObligationStackList::empty(), obligation)
- })
+ )
}
/// Evaluates the predicates in `predicates` recursively. Note that
self.infcx.projection_cache.borrow_mut().complete(key);
}
result
- }
- Ok(None) => {
- Ok(EvaluatedToAmbig)
- }
- Err(_) => {
- Ok(EvaluatedToErr)
- }
+ },
+ Ok(None) => Ok(EvaluatedToAmbig),
+ Err(_) => Ok(EvaluatedToErr)
}
}
} else {
Ok(EvaluatedToErr)
}
- }
- None => {
- Ok(EvaluatedToAmbig)
- }
+ },
+ None => Ok(EvaluatedToAmbig)
}
}
// same unbound type variable.
if let Some(rec_index) =
stack.iter()
- .skip(1) // skip top-most frame
- .position(|prev| stack.obligation.param_env == prev.obligation.param_env &&
- stack.fresh_trait_ref == prev.fresh_trait_ref)
+ .skip(1) // skip top-most frame
+ .position(|prev| stack.obligation.param_env == prev.obligation.param_env &&
+ stack.fresh_trait_ref == prev.fresh_trait_ref)
{
debug!("evaluate_stack({:?}) --> recursive",
stack.fresh_trait_ref);
- let cycle = stack.iter().skip(1).take(rec_index+1);
+ let cycle = stack.iter().skip(1).take(rec_index + 1);
let cycle = cycle.map(|stack| ty::Predicate::Trait(stack.obligation.predicate));
if self.coinductive_match(cycle) {
debug!("evaluate_stack({:?}) --> recursive, coinductive",
let result = match predicate {
ty::Predicate::Trait(ref data) => {
self.tcx().trait_is_auto(data.def_id())
- }
- _ => {
- false
- }
+ },
+ _ => false
};
debug!("coinductive_predicate({:?}) = {:?}", predicate, result);
result
}
// If no match, compute result and insert into cache.
- let (candidate, dep_node) = self.in_task(|this| {
+ let (candidate, dep_node) = self.in_task(|this|
this.candidate_from_obligation_no_cache(stack)
- });
+ );
debug!("CACHE MISS: SELECT({:?})={:?}",
cache_fresh_trait_pred, candidate);
fn in_task<OP, R>(&mut self, op: OP) -> (R, DepNodeIndex)
where OP: FnOnce(&mut Self) -> R
{
- let (result, dep_node) = self.tcx().dep_graph.with_anon_task(DepKind::TraitSelect, || {
+ let (result, dep_node) = self.tcx().dep_graph.with_anon_task(DepKind::TraitSelect, ||
op(self)
- });
+ );
self.tcx().dep_graph.read_index(dep_node);
(result, dep_node)
}
return Ok(None);
}
- match self.is_knowable(stack) {
- None => {}
- Some(conflict) => {
- debug!("coherence stage: not knowable");
- if self.intercrate_ambiguity_causes.is_some() {
- debug!("evaluate_stack: intercrate_ambiguity_causes is some");
- // Heuristics: show the diagnostics when there are no candidates in crate.
- if let Ok(candidate_set) = self.assemble_candidates(stack) {
- let no_candidates_apply =
- candidate_set
- .vec
- .iter()
- .map(|c| self.evaluate_candidate(stack, &c))
- .collect::<Result<Vec<_>, OverflowError>>()?
- .iter()
- .all(|r| !r.may_apply());
- if !candidate_set.ambiguous && no_candidates_apply {
- let trait_ref = stack.obligation.predicate.skip_binder().trait_ref;
- let self_ty = trait_ref.self_ty();
- let trait_desc = trait_ref.to_string();
- let self_desc = if self_ty.has_concrete_skeleton() {
- Some(self_ty.to_string())
- } else {
- None
- };
- let cause = if let Conflict::Upstream = conflict {
- IntercrateAmbiguityCause::UpstreamCrateUpdate {
- trait_desc,
- self_desc,
- }
- } else {
- IntercrateAmbiguityCause::DownstreamCrate { trait_desc, self_desc }
- };
- debug!("evaluate_stack: pushing cause = {:?}", cause);
- self.intercrate_ambiguity_causes.as_mut().unwrap().push(cause);
+ if let Some(conflict) = self.is_knowable(stack) {
+ debug!("coherence stage: not knowable");
+ if self.intercrate_ambiguity_causes.is_some() {
+ debug!("evaluate_stack: intercrate_ambiguity_causes is some");
+ // Heuristics: show the diagnostics when there are no candidates in crate.
+ if let Ok(candidate_set) = self.assemble_candidates(stack) {
+ let mut no_candidates_apply = true;
+ {
+ let evaluated_candidates = candidate_set.vec.iter().map(|c|
+ self.evaluate_candidate(stack, &c));
+
+ for ec in evaluated_candidates {
+ match ec {
+ Ok(c) => {
+ if c.may_apply() {
+ no_candidates_apply = false;
+ break
+ }
+ },
+ Err(e) => return Err(e.into())
+ }
}
}
+
+ if !candidate_set.ambiguous && no_candidates_apply {
+ let trait_ref = stack.obligation.predicate.skip_binder().trait_ref;
+ let self_ty = trait_ref.self_ty();
+ let trait_desc = trait_ref.to_string();
+ let self_desc = if self_ty.has_concrete_skeleton() {
+ Some(self_ty.to_string())
+ } else {
+ None
+ };
+ let cause = if let Conflict::Upstream = conflict {
+ IntercrateAmbiguityCause::UpstreamCrateUpdate {
+ trait_desc,
+ self_desc,
+ }
+ } else {
+ IntercrateAmbiguityCause::DownstreamCrate { trait_desc, self_desc }
+ };
+ debug!("evaluate_stack: pushing cause = {:?}", cause);
+ self.intercrate_ambiguity_causes.as_mut().unwrap().push(cause);
+ }
}
- return Ok(None);
}
+ return Ok(None);
}
let candidate_set = self.assemble_candidates(stack)?;
// Other bounds. Consider both in-scope bounds from fn decl
// and applicable impls. There is a certain set of precedence rules here.
-
let def_id = obligation.predicate.def_id();
let lang_items = self.tcx().lang_items();
+
if lang_items.copy_trait() == Some(def_id) {
debug!("obligation self ty is {:?}",
obligation.predicate.skip_binder().self_ty());
ty::Projection(_) | ty::Opaque(..) => {}
ty::Infer(ty::TyVar(_)) => {
span_bug!(obligation.cause.span,
- "Self=_ should have been handled by assemble_candidates");
+ "Self=_ should have been handled by assemble_candidates");
}
_ => return
}
- let result = self.probe(|this, snapshot| {
+ let result = self.probe(|this, snapshot|
this.match_projection_obligation_against_definition_bounds(obligation,
snapshot)
- });
+ );
if result {
candidates.vec.push(ProjectionCandidate);
span_bug!(
obligation.cause.span,
"match_projection_obligation_against_definition_bounds() called \
- but self-ty not a projection: {:?}",
+ but self-ty is not a projection: {:?}",
skol_trait_predicate.trait_ref.self_ty());
}
};
where_clause_trait_ref: ty::PolyTraitRef<'tcx>)
-> Result<EvaluationResult, OverflowError>
{
- self.probe(move |this, _| {
+ self.probe(move |this, _|
match this.match_where_clause_trait_ref(stack.obligation, where_clause_trait_ref) {
Ok(obligations) => {
this.evaluate_predicates_recursively(stack.list(), obligations.iter())
}
Err(()) => Ok(EvaluatedToErr)
}
- })
+ )
}
fn assemble_generator_candidates(&mut self,
obligation);
candidates.vec.push(GeneratorCandidate);
- Ok(())
}
ty::Infer(ty::TyVar(_)) => {
debug!("assemble_generator_candidates: ambiguous self-type");
candidates.ambiguous = true;
- return Ok(());
}
- _ => { return Ok(()); }
+ _ => {}
}
+
+ Ok(())
}
/// Check for the artificial impl that the compiler will create for an obligation like `X :
debug!("assemble_unboxed_candidates: closure_kind not yet known");
candidates.vec.push(ClosureCandidate);
}
- };
- Ok(())
+ }
}
ty::Infer(ty::TyVar(_)) => {
debug!("assemble_unboxed_closure_candidates: ambiguous self-type");
candidates.ambiguous = true;
- return Ok(());
}
- _ => { return Ok(()); }
+ _ => {}
}
+
+ Ok(())
}
/// Implement one of the `Fn()` family for a fn pointer.
debug!("assemble_fn_pointer_candidates: ambiguous self-type");
candidates.ambiguous = true; // could wind up being a fn() type
}
-
// provide an impl, but only for suitable `fn` pointers
ty::FnDef(..) | ty::FnPtr(_) => {
if let ty::FnSig {
candidates.vec.push(FnPointerCandidate);
}
}
-
- _ => { }
+ _ => {}
}
Ok(())
obligation.predicate.def_id(),
obligation.predicate.skip_binder().trait_ref.self_ty(),
|impl_def_id| {
- self.probe(|this, snapshot| { /* [1] */
- match this.match_impl(impl_def_id, obligation, snapshot) {
- Ok(skol_map) => {
- candidates.vec.push(ImplCandidate(impl_def_id));
-
- // NB: we can safely drop the skol map
- // since we are in a probe [1]
- mem::drop(skol_map);
- }
- Err(_) => { }
+ self.probe(|this, snapshot| /* [1] */
+ if let Ok(skol_map) = this.match_impl(impl_def_id, obligation, snapshot) {
+ candidates.vec.push(ImplCandidate(impl_def_id));
+
+ // NB: we can safely drop the skol map
+ // since we are in a probe [1]
+ mem::drop(skol_map);
}
- });
+ );
}
);
ty::Dynamic(ref data, ..) => {
if data.auto_traits().any(|did| did == obligation.predicate.def_id()) {
debug!("assemble_candidates_from_object_ty: matched builtin bound, \
- pushing candidate");
+ pushing candidate");
candidates.vec.push(BuiltinObjectCandidate);
return;
}
candidates.ambiguous = true; // could wind up being an object type
return;
}
- _ => {
- return;
- }
+ _ => return
};
debug!("assemble_candidates_from_object_ty: poly_trait_ref={:?}",
// but `Foo` is declared as `trait Foo : Bar<u32>`.
let upcast_trait_refs =
util::supertraits(this.tcx(), poly_trait_ref)
- .filter(|upcast_trait_ref| {
+ .filter(|upcast_trait_ref|
this.probe(|this, _| {
let upcast_trait_ref = upcast_trait_ref.clone();
this.match_poly_trait_ref(obligation, upcast_trait_ref).is_ok()
})
- })
+ )
.count();
if upcast_trait_refs > 1 {
other: &EvaluatedCandidate<'tcx>)
-> bool
{
+ if victim.candidate == other.candidate {
+ return true;
+ }
+
// Check if a bound would previously have been removed when normalizing
// the param_env so that it can be given the lowest priority. See
// #50825 for the motivation for this.
cand.is_global() && !cand.has_late_bound_regions()
};
- if victim.candidate == other.candidate {
- return true;
- }
-
match other.candidate {
// Prefer BuiltinCandidate { has_nested: false } to anything else.
// This is a fix for #53123 and prevents winnowing from accidentally extending the
BuiltinCandidate { has_nested: false } => true,
ParamCandidate(ref cand) => match victim.candidate {
AutoImplCandidate(..) => {
- bug!(
- "default implementations shouldn't be recorded \
- when there are other valid candidates");
+ bug!("default implementations shouldn't be recorded \
+ when there are other valid candidates");
}
// Prefer BuiltinCandidate { has_nested: false } to anything else.
// This is a fix for #53123 and prevents winnowing from accidentally extending the
ObjectCandidate |
ProjectionCandidate => match victim.candidate {
AutoImplCandidate(..) => {
- bug!(
- "default implementations shouldn't be recorded \
- when there are other valid candidates");
+ bug!("default implementations shouldn't be recorded \
+ when there are other valid candidates");
}
// Prefer BuiltinCandidate { has_nested: false } to anything else.
// This is a fix for #53123 and prevents winnowing from accidentally extending the
fn assemble_builtin_bound_candidates<'o>(&mut self,
conditions: BuiltinImplConditions<'tcx>,
candidates: &mut SelectionCandidateSet<'tcx>)
- -> Result<(),SelectionError<'tcx>>
+ -> Result<(), SelectionError<'tcx>>
{
match conditions {
BuiltinImplConditions::Where(nested) => {
candidates.vec.push(BuiltinCandidate {
has_nested: nested.skip_binder().len() > 0
});
- Ok(())
}
- BuiltinImplConditions::None => { Ok(()) }
+ BuiltinImplConditions::None => {}
BuiltinImplConditions::Ambiguous => {
debug!("assemble_builtin_bound_candidates: ambiguous builtin");
- Ok(candidates.ambiguous = true)
+ candidates.ambiguous = true;
}
}
+
+ Ok(())
}
- fn sized_conditions(&mut self, obligation: &TraitObligation<'tcx>)
- -> BuiltinImplConditions<'tcx>
+ fn sized_conditions(&mut self,
+ obligation: &TraitObligation<'tcx>)
+ -> BuiltinImplConditions<'tcx>
{
use self::BuiltinImplConditions::{Ambiguous, None, Where};
}
}
- fn copy_clone_conditions(&mut self, obligation: &TraitObligation<'tcx>)
- -> BuiltinImplConditions<'tcx>
+ fn copy_clone_conditions(&mut self,
+ obligation: &TraitObligation<'tcx>)
+ -> BuiltinImplConditions<'tcx>
{
// NOTE: binder moved to (*)
let self_ty = self.infcx.shallow_resolve(
let lang_items = self.tcx().lang_items();
let obligations = if has_nested {
let trait_def = obligation.predicate.def_id();
- let conditions = match trait_def {
- _ if Some(trait_def) == lang_items.sized_trait() => {
+ let conditions =
+ if Some(trait_def) == lang_items.sized_trait() {
self.sized_conditions(obligation)
- }
- _ if Some(trait_def) == lang_items.copy_trait() => {
+ } else if Some(trait_def) == lang_items.copy_trait() {
self.copy_clone_conditions(obligation)
- }
- _ if Some(trait_def) == lang_items.clone_trait() => {
+ } else if Some(trait_def) == lang_items.clone_trait() {
self.copy_clone_conditions(obligation)
- }
- _ => bug!("unexpected builtin trait {:?}", trait_def)
+ } else {
+ bug!("unexpected builtin trait {:?}", trait_def)
};
let nested = match conditions {
BuiltinImplConditions::Where(nested) => nested,
/// See `confirm_auto_impl_candidate`
fn vtable_auto_impl(&mut self,
- obligation: &TraitObligation<'tcx>,
- trait_def_id: DefId,
- nested: ty::Binder<Vec<Ty<'tcx>>>)
-
-> VtableAutoImplData<PredicateObligation<'tcx>>
+ obligation: &TraitObligation<'tcx>,
+ trait_def_id: DefId,
+ nested: ty::Binder<Vec<Ty<'tcx>>>)
+ -> VtableAutoImplData<PredicateObligation<'tcx>>
{
debug!("vtable_auto_impl: nested={:?}", nested);
ty::Dynamic(ref data, ..) => {
data.principal().unwrap().with_self_ty(self.tcx(), self_ty)
}
- _ => {
- span_bug!(obligation.cause.span,
- "object candidate with non-object");
- }
+ _ => span_bug!(obligation.cause.span,
+ "object candidate with non-object")
};
let mut upcast_trait_ref = None;
// record it for later.)
let nonmatching =
util::supertraits(tcx, poly_trait_ref)
- .take_while(|&t| {
- match
- self.commit_if_ok(
- |this, _| this.match_poly_trait_ref(obligation, t))
+ .take_while(|&t|
+ match self.commit_if_ok(|this, _|
+ this.match_poly_trait_ref(obligation, t))
{
Ok(obligations) => {
upcast_trait_ref = Some(t);
}
Err(_) => { true }
}
- });
+ );
// Additionally, for each of the nonmatching predicates that
// we pass over, we sum up the set of number of vtable
// entries, so that we can compute the offset for the selected
// trait.
- vtable_base =
- nonmatching.map(|t| tcx.count_own_vtable_entries(t))
- .sum();
-
+ vtable_base = nonmatching.map(|t| tcx.count_own_vtable_entries(t)).sum();
}
VtableObjectData {
fn confirm_generator_candidate(&mut self,
obligation: &TraitObligation<'tcx>)
-> Result<VtableGeneratorData<'tcx, PredicateObligation<'tcx>>,
- SelectionError<'tcx>>
+ SelectionError<'tcx>>
{
// ok to skip binder because the substs on generator types never
// touch bound regions, they just capture the in-scope
{
debug!("confirm_closure_candidate({:?})", obligation);
- let kind = match self.tcx().lang_items().fn_trait_kind(obligation.predicate.def_id()) {
- Some(k) => k,
- None => bug!("closure candidate for non-fn trait {:?}", obligation)
- };
+ let kind = self.tcx()
+ .lang_items()
+ .fn_trait_kind(obligation.predicate.def_id())
+ .unwrap_or_else(|| bug!("closure candidate for non-fn trait {:?}",
+ obligation));
// ok to skip binder because the substs on closure types never
// touch bound regions, they just capture the in-scope
obligations.extend(
self.confirm_poly_trait_refs(obligation.cause.clone(),
- obligation.param_env,
- obligation.predicate.to_poly_trait_ref(),
- trait_ref)?);
+ obligation.param_env,
+ obligation.predicate.to_poly_trait_ref(),
+ trait_ref)?);
obligations.push(Obligation::new(
obligation.cause.clone(),
(_, &ty::Dynamic(ref data, r)) => {
let mut object_dids =
data.auto_traits().chain(data.principal().map(|p| p.def_id()));
- if let Some(did) = object_dids.find(|did| {
- !tcx.is_object_safe(*did)
- }) {
+ if let Some(did) = object_dids.find(|did| !tcx.is_object_safe(*did)) {
return Err(TraitNotObjectSafe(did))
}
let cause = ObligationCause::new(obligation.cause.span,
obligation.cause.body_id,
ObjectCastObligation(target));
- let mut push = |predicate| {
- nested.push(Obligation::with_depth(cause.clone(),
- obligation.recursion_depth + 1,
- obligation.param_env,
- predicate));
+
+ let predicate_to_obligation = |predicate| {
+ Obligation::with_depth(cause.clone(),
+ obligation.recursion_depth + 1,
+ obligation.param_env,
+ predicate)
};
// Create obligations:
// words, if the object type is Foo+Send, this would create an obligation for the
// Send check.)
// - Projection predicates
- for predicate in data.iter() {
- push(predicate.with_self_ty(tcx, source));
- }
+ nested.extend(data.iter().map(|d|
+ predicate_to_obligation(d.with_self_ty(tcx, source))
+ ));
// We can only make objects from sized types.
let tr = ty::TraitRef {
def_id: tcx.require_lang_item(lang_items::SizedTraitLangItem),
substs: tcx.mk_substs_trait(source, &[]),
};
- push(tr.to_predicate());
+ nested.push(predicate_to_obligation(tr.to_predicate()));
// If the type is `Foo+'a`, ensures that the type
// being cast to `Foo+'a` outlives `'a`:
let outlives = ty::OutlivesPredicate(source, r);
- push(ty::Binder::dummy(outlives).to_predicate());
+ nested.push(predicate_to_obligation(
+ ty::Binder::dummy(outlives).to_predicate()));
}
// [T; n] -> [T].
// Check that the source struct with the target's
// unsized parameters is equal to the target.
- let params = substs_a.iter().enumerate().map(|(i, &k)| {
+ let params = substs_a.iter().enumerate().map(|(i, &k)|
if ty_params.contains(i) {
substs_b.type_at(i).into()
} else {
k
}
- });
+ );
let new_struct = tcx.mk_adt(def, tcx.mk_substs(params));
let InferOk { obligations, .. } =
self.infcx.at(&obligation.cause, obligation.param_env)
let InferOk { obligations, .. } =
self.infcx.at(&obligation.cause, obligation.param_env)
.eq(skol_obligation_trait_ref, impl_trait_ref)
- .map_err(|e| {
- debug!("match_impl: failed eq_trait_refs due to `{}`", e);
- ()
- })?;
+ .map_err(|e|
+ debug!("match_impl: failed eq_trait_refs due to `{}`", e)
+ )?;
nested_obligations.extend(obligations);
if let Err(e) = self.infcx.leak_check(false,
fn match_where_clause_trait_ref(&mut self,
obligation: &TraitObligation<'tcx>,
where_clause_trait_ref: ty::PolyTraitRef<'tcx>)
- -> Result<Vec<PredicateObligation<'tcx>>,()>
+ -> Result<Vec<PredicateObligation<'tcx>>, ()>
{
self.match_poly_trait_ref(obligation, where_clause_trait_ref)
}
fn match_poly_trait_ref(&mut self,
obligation: &TraitObligation<'tcx>,
poly_trait_ref: ty::PolyTraitRef<'tcx>)
- -> Result<Vec<PredicateObligation<'tcx>>,()>
+ -> Result<Vec<PredicateObligation<'tcx>>, ()>
{
debug!("match_poly_trait_ref: obligation={:?} poly_trait_ref={:?}",
obligation,
// in fact unparameterized (or at least does not reference any
// regions bound in the obligation). Still probably some
// refactoring could make this nicer.
-
self.tcx().closure_trait_ref_and_return_type(obligation.predicate.def_id(),
obligation.predicate
- .skip_binder().self_ty(), // (1)
+ .skip_binder()
+ .self_ty(), // (1)
closure_type,
util::TupleArgumentsFlag::No)
.map_bound(|(trait_ref, _)| trait_ref)
}
fn generator_trait_ref_unnormalized(&mut self,
- obligation: &TraitObligation<'tcx>,
- closure_def_id: DefId,
- substs: ty::GeneratorSubsts<'tcx>)
- -> ty::PolyTraitRef<'tcx>
+ obligation: &TraitObligation<'tcx>,
+ closure_def_id: DefId,
+ substs: ty::GeneratorSubsts<'tcx>)
+ -> ty::PolyTraitRef<'tcx>
{
let gen_sig = substs.poly_sig(closure_def_id, self.tcx());
self.tcx().generator_trait_ref_and_outputs(obligation.predicate.def_id(),
obligation.predicate
- .skip_binder().self_ty(), // (1)
+ .skip_binder()
+ .self_ty(), // (1)
gen_sig)
.map_bound(|(trait_ref, ..)| trait_ref)
}
impl<'tcx> TraitObligation<'tcx> {
#[allow(unused_comparisons)]
pub fn derived_cause(&self,
- variant: fn(DerivedObligationCause<'tcx>) -> ObligationCauseCode<'tcx>)
- -> ObligationCause<'tcx>
+ variant: fn(DerivedObligationCause<'tcx>) -> ObligationCauseCode<'tcx>)
+ -> ObligationCause<'tcx>
{
/*!
* Creates a cause for obligations that are derived from
}
fulfill_implication(infcx, param_env, source_trait_ref, target_impl)
- .unwrap_or_else(|_| {
+ .unwrap_or_else(|_|
bug!("When translating substitutions for specialization, the expected \
specialization failed to hold")
- })
+ )
}
specialization_graph::Node::Trait(..) => source_trait_ref.substs,
};
let substs = translate_substs(&infcx, param_env, impl_data.impl_def_id,
substs, node_item.node);
let substs = infcx.tcx.erase_regions(&substs);
- tcx.lift(&substs).unwrap_or_else(|| {
+ tcx.lift(&substs).unwrap_or_else(||
bug!("find_method: translate_substs \
returned {:?} which contains inference types/regions",
- substs);
- })
+ substs)
+ )
});
(node_item.item.def_id, substs)
}
- None => {
- bug!("{:?} not found in {:?}", item, impl_data.impl_def_id)
- }
+ None => bug!("{:?} not found in {:?}", item, impl_data.impl_def_id)
}
}
-> Lrc<specialization_graph::Graph> {
let mut sg = specialization_graph::Graph::new();
- let mut trait_impls = Vec::new();
- tcx.for_each_impl(trait_id, |impl_did| trait_impls.push(impl_did));
+ let mut trait_impls = tcx.all_impls(trait_id);
// The coherence checking implementation seems to rely on impls being
// iterated over (roughly) in definition order, so we are sorting by
"first implementation here".to_string());
err.span_label(impl_span,
format!("conflicting implementation{}",
- overlap.self_desc
- .map_or(String::new(),
- |ty| format!(" for `{}`", ty))));
+ overlap.self_desc
+ .map_or(String::new(),
+ |ty| format!(" for `{}`", ty))));
}
Err(cname) => {
let msg = match to_pretty_impl_header(tcx, overlap.with_impl) {
// The predicates will contain default bounds like `T: Sized`. We need to
// remove these bounds, and add `T: ?Sized` to any untouched type parameters.
let predicates = tcx.predicates_of(impl_def_id).predicates;
- let mut pretty_predicates = Vec::with_capacity(predicates.len());
+ let mut pretty_predicates = Vec::with_capacity(
+ predicates.len() + types_without_default_bounds.len());
+
for p in predicates {
if let Some(poly_trait_ref) = p.to_opt_poly_trait_ref() {
if Some(poly_trait_ref.def_id()) == sized_trait {
}
pretty_predicates.push(p.to_string());
}
+
pretty_predicates.extend(
types_without_default_bounds.iter().map(|ty| format!("{}: ?Sized", ty))
);
+
if !pretty_predicates.is_empty() {
write!(w, "\n where {}", pretty_predicates.join(", ")).unwrap();
}
let cur = self.current_source.take();
if let Some(Node::Impl(cur_impl)) = cur {
let parent = self.specialization_graph.parent(cur_impl);
- if parent == self.trait_def_id {
- self.current_source = Some(Node::Trait(parent));
+
+ self.current_source = if parent == self.trait_def_id {
+ Some(Node::Trait(parent))
} else {
- self.current_source = Some(Node::Impl(parent));
- }
+ Some(Node::Impl(parent))
+ };
}
cur
}
match *self {
super::Unimplemented => Some(super::Unimplemented),
super::OutputTypeParameterMismatch(a, b, ref err) => {
- tcx.lift(&(a, b)).and_then(|(a, b)| {
+ tcx.lift(&(a, b)).and_then(|(a, b)|
tcx.lift(err)
.map(|err| super::OutputTypeParameterMismatch(a, b, err))
- })
+ )
}
super::TraitNotObjectSafe(def_id) => Some(super::TraitNotObjectSafe(def_id)),
super::ConstEvalFailure(ref err) => tcx.lift(&**err).map(|err| super::ConstEvalFailure(
super::ReferenceOutlivesReferent(ty) => {
tcx.lift(&ty).map(super::ReferenceOutlivesReferent)
}
- super::ObjectTypeBound(ty, r) => tcx.lift(&ty).and_then(|ty| {
+ super::ObjectTypeBound(ty, r) => tcx.lift(&ty).and_then(|ty|
tcx.lift(&r)
- .and_then(|r| Some(super::ObjectTypeBound(ty, r)))
- }),
+ .and_then(|r| Some(super::ObjectTypeBound(ty, r)))
+ ),
super::ObjectCastObligation(ty) => tcx.lift(&ty).map(super::ObjectCastObligation),
super::AssignmentLhsSized => Some(super::AssignmentLhsSized),
super::TupleInitializerSized => Some(super::TupleInitializerSized),
impl<'a, 'tcx> Lift<'tcx> for traits::DerivedObligationCause<'a> {
type Lifted = traits::DerivedObligationCause<'tcx>;
fn lift_to_tcx<'b, 'gcx>(&self, tcx: TyCtxt<'b, 'gcx, 'tcx>) -> Option<Self::Lifted> {
- tcx.lift(&self.parent_trait_ref).and_then(|trait_ref| {
+ tcx.lift(&self.parent_trait_ref).and_then(|trait_ref|
tcx.lift(&*self.parent_code)
- .map(|code| traits::DerivedObligationCause {
- parent_trait_ref: trait_ref,
- parent_code: Rc::new(code),
- })
- })
+ .map(|code| traits::DerivedObligationCause {
+ parent_trait_ref: trait_ref,
+ parent_code: Rc::new(code),
+ })
+ )
}
}
impl_def_id,
substs,
nested,
- }) => tcx.lift(&substs).map(|substs| {
+ }) => tcx.lift(&substs).map(|substs|
traits::VtableImpl(traits::VtableImplData {
impl_def_id,
substs,
nested,
})
- }),
+ ),
traits::VtableAutoImpl(t) => Some(traits::VtableAutoImpl(t)),
traits::VtableGenerator(traits::VtableGeneratorData {
generator_def_id,
substs,
nested,
- }) => tcx.lift(&substs).map(|substs| {
+ }) => tcx.lift(&substs).map(|substs|
traits::VtableGenerator(traits::VtableGeneratorData {
generator_def_id: generator_def_id,
substs: substs,
nested: nested,
})
- }),
+ ),
traits::VtableClosure(traits::VtableClosureData {
closure_def_id,
substs,
nested,
- }) => tcx.lift(&substs).map(|substs| {
+ }) => tcx.lift(&substs).map(|substs|
traits::VtableClosure(traits::VtableClosureData {
closure_def_id,
substs,
nested,
})
- }),
+ ),
traits::VtableFnPointer(traits::VtableFnPointerData { fn_ty, nested }) => {
- tcx.lift(&fn_ty).map(|fn_ty| {
+ tcx.lift(&fn_ty).map(|fn_ty|
traits::VtableFnPointer(traits::VtableFnPointerData { fn_ty, nested })
- })
+ )
}
traits::VtableParam(n) => Some(traits::VtableParam(n)),
traits::VtableBuiltin(n) => Some(traits::VtableBuiltin(n)),
upcast_trait_ref,
vtable_base,
nested,
- }) => tcx.lift(&upcast_trait_ref).map(|trait_ref| {
+ }) => tcx.lift(&upcast_trait_ref).map(|trait_ref|
traits::VtableObject(traits::VtableObjectData {
upcast_trait_ref: trait_ref,
vtable_base,
nested,
})
- }),
+ ),
}
}
}
Some(ty::Predicate::Trait(data)) => {
return Some(data.to_poly_trait_ref());
}
- Some(_) => {
- }
+ Some(_) => {}
}
}
}
}
}
}
+
+ /// Return a vector containing all impls
+ pub fn all_impls(self, def_id: DefId) -> Vec<DefId> {
+ let impls = self.trait_impls_of(def_id);
+
+ impls.blanket_impls.iter().chain(
+ impls.non_blanket_impls.values().flatten()
+ ).cloned().collect()
+ }
}
// Query provider for `trait_impls_of`.
.sig
.inputs()
.iter()
- .map(|ty| ArgKind::from_expected_ty(ty))
+ .map(|ty| ArgKind::from_expected_ty(ty, None))
.collect();
let (closure_span, found_args) = self.get_fn_like_arguments(expr_map_node);
let expected_span = expected_sig.cause_span.unwrap_or(closure_span);
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