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Auto merge of #49251 - nikomatsakis:issue-15872-elision-impl-header, r=cramertj

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support elision in impl headers

You can now do things like:

```
impl MyTrait<'_> for &u32 { ... }
```

Each `'_` or elided lifetime is a fresh parameter. `'_` and elision are still not permitted in associated type values. (Plausibly we could support that if there is a single input lifetime.) The original lifetime elision RFC was a bit unclear on this point: [as documented here, I think this is the correct interpretation, both because it fits existing impls and it's most analogous to the behavior in fns](https://github.com/rust-lang/rust/issues/15872#issuecomment-338700138).

We do not support elision with deprecated forms:

```
impl MyTrait for std::cell::Ref<u32> { } // ERROR
```

Builds on the in-band lifetime stuff.

r? @cramertj

Fixes #15872
This commit is contained in:
bors
2018-03-24 13:23:17 +00:00
parent a0b0f5fba5 94468dac63
commit b4aa80dd73
20 changed files with 2081 additions and 1107 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/librustc/hir/intravisit.rs
+4 -1
View File
@@ -420,7 +420,10 @@ pub fn walk_lifetime<'v, V: Visitor<'v>>(visitor: &mut V, lifetime: &'v Lifetime
LifetimeName::Name(name) => {
visitor.visit_name(lifetime.span, name);
}
LifetimeName::Static | LifetimeName::Implicit | LifetimeName::Underscore => {}
LifetimeName::Fresh(_) |
LifetimeName::Static |
LifetimeName::Implicit |
LifetimeName::Underscore => {}
}
}
src/librustc/hir/lowering.rs
+1552 -1034
View File
@@ -43,8 +43,8 @@
use dep_graph::DepGraph;
use hir;
use hir::HirVec;
use hir::map::{Definitions, DefKey, DefPathData};
use hir::def_id::{DefIndex, DefId, CRATE_DEF_INDEX, DefIndexAddressSpace};
use hir::map::{DefKey, DefPathData, Definitions};
use hir::def_id::{DefId, DefIndex, DefIndexAddressSpace, CRATE_DEF_INDEX};
use hir::def::{Def, PathResolution};
use lint::builtin::{self, PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES};
use middle::cstore::CrateStore;
@@ -63,10 +63,10 @@
use syntax::ext::hygiene::{Mark, SyntaxContext};
use syntax::print::pprust;
use syntax::ptr::P;
use syntax::codemap::{self, respan, Spanned, CompilerDesugaringKind};
use syntax::codemap::{self, respan, CompilerDesugaringKind, Spanned};
use syntax::std_inject;
use syntax::symbol::{Symbol, keywords};
use syntax::tokenstream::{TokenStream, TokenTree, Delimited};
use syntax::symbol::{keywords, Symbol};
use syntax::tokenstream::{Delimited, TokenStream, TokenTree};
use syntax::parse::token::Token;
use syntax::util::small_vector::SmallVector;
use syntax::visit::{self, Visitor};
@@ -80,13 +80,13 @@ pub struct LoweringContext<'a> {
// Use to assign ids to hir nodes that do not directly correspond to an ast node
sess: &'a Session,
cstore: &'a dyn CrateStore,
cstore: &'a CrateStore,
// As we walk the AST we must keep track of the current 'parent' def id (in
// the form of a DefIndex) so that if we create a new node which introduces
// a definition, then we can properly create the def id.
parent_def: Option<DefIndex>,
resolver: &'a mut dyn Resolver,
resolver: &'a mut Resolver,
name_map: FxHashMap<Ident, Name>,
/// The items being lowered are collected here.
@@ -107,6 +107,12 @@ pub struct LoweringContext<'a> {
is_in_loop_condition: bool,
is_in_trait_impl: bool,
/// What to do when we encounter either an "anonymous lifetime
/// reference". The term "anonymous" is meant to encompass both
/// `'_` lifetimes as well as fully elided cases where nothing is
/// written at all (e.g., `&T` or `std::cell::Ref<T>`).
anonymous_lifetime_mode: AnonymousLifetimeMode,
// This is a list of in-band type definitions being generated by
// Argument-position `impl Trait`.
// When traversing a signature such as `fn foo(x: impl Trait)`,
@@ -121,13 +127,15 @@ pub struct LoweringContext<'a> {
// (i.e. it doesn't appear in the in_scope_lifetimes list), it is added
// to this list. The results of this list are then added to the list of
// lifetime definitions in the corresponding impl or function generics.
lifetimes_to_define: Vec<(Span, Name)>,
lifetimes_to_define: Vec<(Span, hir::LifetimeName)>,
// Whether or not in-band lifetimes are being collected. This is used to
// indicate whether or not we're in a place where new lifetimes will result
// in in-band lifetime definitions, such a function or an impl header.
// This will always be false unless the `in_band_lifetimes` feature is
// enabled.
is_collecting_in_band_lifetimes: bool,
// Currently in-scope lifetimes defined in impl headers, fn headers, or HRTB.
// When `is_collectin_in_band_lifetimes` is true, each lifetime is checked
// against this list to see if it is already in-scope, or if a definition
@@ -154,8 +162,13 @@ pub trait Resolver {
/// Given suffix ["b","c","d"], creates a HIR path for `[::crate_root]::b::c::d` and resolves
/// it based on `is_value`.
fn resolve_str_path(&mut self, span: Span, crate_root: Option<&str>,
components: &[&str], is_value: bool) -> hir::Path;
fn resolve_str_path(
&mut self,
span: Span,
crate_root: Option<&str>,
components: &[&str],
is_value: bool,
) -> hir::Path;
}
#[derive(Clone, Copy, Debug)]
@@ -176,12 +189,13 @@ enum ImplTraitContext {
Disallowed,
}
pub fn lower_crate(sess: &Session,
cstore: &dyn CrateStore,
dep_graph: &DepGraph,
krate: &Crate,
resolver: &mut dyn Resolver)
-> hir::Crate {
pub fn lower_crate(
sess: &Session,
cstore: &CrateStore,
dep_graph: &DepGraph,
krate: &Crate,
resolver: &mut Resolver,
) -> hir::Crate {
// We're constructing the HIR here; we don't care what we will
// read, since we haven't even constructed the *input* to
// incr. comp. yet.
@@ -204,6 +218,7 @@ pub fn lower_crate(sess: &Session,
catch_scopes: Vec::new(),
loop_scopes: Vec::new(),
is_in_loop_condition: false,
anonymous_lifetime_mode: AnonymousLifetimeMode::PassThrough,
type_def_lifetime_params: DefIdMap(),
current_hir_id_owner: vec![(CRATE_DEF_INDEX, 0)],
item_local_id_counters: NodeMap(),
@@ -222,7 +237,7 @@ enum ParamMode {
/// Any path in a type context.
Explicit,
/// The `module::Type` in `module::Type::method` in an expression.
Optional
Optional,
}
struct LoweredNodeId {
@@ -236,6 +251,51 @@ enum ParenthesizedGenericArgs {
Err,
}
/// What to do when we encounter an **anonymous** lifetime
/// reference. Anonymous lifetime references come in two flavors. You
/// have implicit, or fully elided, references to lifetimes, like the
/// one in `&T` or `Ref<T>`, and you have `'_` lifetimes, like `&'_ T`
/// or `Ref<'_, T>`. These often behave the same, but not always:
///
/// - certain usages of implicit references are deprecated, like
/// `Ref<T>`, and we sometimes just give hard errors in those cases
/// as well.
/// - for object bounds there is a difference: `Box<dyn Foo>` is not
/// the same as `Box<dyn Foo + '_>`.
///
/// We describe the effects of the various modes in terms of three cases:
///
/// - **Modern** -- includes all uses of `'_`, but also the lifetime arg
/// of a `&` (e.g., the missing lifetime in something like `&T`)
/// - **Dyn Bound** -- if you have something like `Box<dyn Foo>`,
/// there is an elided lifetime bound (`Box<dyn Foo + 'X>`). These
/// elided bounds follow special rules. Note that this only covers
/// cases where *nothing* is written; the `'_` in `Box<dyn Foo +
/// '_>` is a case of "modern" elision.
/// - **Deprecated** -- this coverse cases like `Ref<T>`, where the lifetime
/// parameter to ref is completely elided. `Ref<'_, T>` would be the modern,
/// non-deprecated equivalent.
///
/// Currently, the handling of lifetime elision is somewhat spread out
/// between HIR lowering and -- as described below -- the
/// `resolve_lifetime` module. Often we "fallthrough" to that code by generating
/// an "elided" or "underscore" lifetime name. In the future, we probably want to move
/// everything into HIR lowering.
#[derive(Copy, Clone)]
enum AnonymousLifetimeMode {
/// For **Modern** cases, create a new anonymous region parameter
/// and reference that.
///
/// For **Dyn Bound** cases, pass responsibility to
/// `resolve_lifetime` code.
///
/// For **Deprecated** cases, report an error.
CreateParameter,
/// Pass responsibility to `resolve_lifetime` code for all cases.
PassThrough,
}
impl<'a> LoweringContext<'a> {
fn lower_crate(mut self, c: &Crate) -> hir::Crate {
/// Full-crate AST visitor that inserts into a fresh
@@ -252,13 +312,15 @@ fn visit_item(&mut self, item: &'lcx Item) {
self.lctx.allocate_hir_id_counter(item.id, item);
match item.node {
ItemKind::Struct(_, ref generics) |
ItemKind::Union(_, ref generics) |
ItemKind::Enum(_, ref generics) |
ItemKind::Ty(_, ref generics) |
ItemKind::Trait(_, _, ref generics, ..) => {
ItemKind::Struct(_, ref generics)
| ItemKind::Union(_, ref generics)
| ItemKind::Enum(_, ref generics)
| ItemKind::Ty(_, ref generics)
| ItemKind::Trait(_, _, ref generics, ..) => {
let def_id = self.lctx.resolver.definitions().local_def_id(item.id);
let count = generics.params.iter()
let count = generics
.params
.iter()
.filter(|param| param.is_lifetime_param())
.count();
self.lctx.type_def_lifetime_params.insert(def_id, count);
@@ -285,7 +347,8 @@ struct ItemLowerer<'lcx, 'interner: 'lcx> {
impl<'lcx, 'interner> ItemLowerer<'lcx, 'interner> {
fn with_trait_impl_ref<F>(&mut self, trait_impl_ref: &Option<TraitRef>, f: F)
where F: FnOnce(&mut Self)
where
F: FnOnce(&mut Self),
{
let old = self.lctx.is_in_trait_impl;
self.lctx.is_in_trait_impl = if let &None = trait_impl_ref {
@@ -311,22 +374,24 @@ fn visit_item(&mut self, item: &'lcx Item) {
if item_lowered {
let item_lifetimes = match self.lctx.items.get(&item.id).unwrap().node {
hir::Item_::ItemImpl(_,_,_,ref generics,..) |
hir::Item_::ItemTrait(_,_,ref generics,..) =>
generics.lifetimes().cloned().collect::<Vec<_>>(),
hir::Item_::ItemImpl(_, _, _, ref generics, ..)
| hir::Item_::ItemTrait(_, _, ref generics, ..) => {
generics.lifetimes().cloned().collect::<Vec<_>>()
}
_ => Vec::new(),
};
self.lctx.with_parent_impl_lifetime_defs(&item_lifetimes, |this| {
let this = &mut ItemLowerer { lctx: this };
if let ItemKind::Impl(_,_,_,_,ref opt_trait_ref,_,_) = item.node {
this.with_trait_impl_ref(opt_trait_ref, |this| {
visit::walk_item(this, item)
});
} else {
visit::walk_item(this, item);
}
});
self.lctx
.with_parent_impl_lifetime_defs(&item_lifetimes, |this| {
let this = &mut ItemLowerer { lctx: this };
if let ItemKind::Impl(_, _, _, _, ref opt_trait_ref, _, _) = item.node {
this.with_trait_impl_ref(opt_trait_ref, |this| {
visit::walk_item(this, item)
});
} else {
visit::walk_item(this, item);
}
});
}
}
@@ -379,27 +444,26 @@ fn visit_impl_item(&mut self, item: &'lcx ImplItem) {
}
}
fn allocate_hir_id_counter<T: Debug>(&mut self,
owner: NodeId,
debug: &T) {
fn allocate_hir_id_counter<T: Debug>(&mut self, owner: NodeId, debug: &T) {
if self.item_local_id_counters.insert(owner, 0).is_some() {
bug!("Tried to allocate item_local_id_counter for {:?} twice", debug);
bug!(
"Tried to allocate item_local_id_counter for {:?} twice",
debug
);
}
// Always allocate the first HirId for the owner itself
self.lower_node_id_with_owner(owner, owner);
}
fn lower_node_id_generic<F>(&mut self,
ast_node_id: NodeId,
alloc_hir_id: F)
-> LoweredNodeId
where F: FnOnce(&mut Self) -> hir::HirId
fn lower_node_id_generic<F>(&mut self, ast_node_id: NodeId, alloc_hir_id: F) -> LoweredNodeId
where
F: FnOnce(&mut Self) -> hir::HirId,
{
if ast_node_id == DUMMY_NODE_ID {
return LoweredNodeId {
node_id: DUMMY_NODE_ID,
hir_id: hir::DUMMY_HIR_ID,
}
};
}
let min_size = ast_node_id.as_usize() + 1;
@@ -427,11 +491,12 @@ fn lower_node_id_generic<F>(&mut self,
}
fn with_hir_id_owner<F>(&mut self, owner: NodeId, f: F)
where F: FnOnce(&mut Self)
where
F: FnOnce(&mut Self),
{
let counter = self.item_local_id_counters
.insert(owner, HIR_ID_COUNTER_LOCKED)
.unwrap();
.insert(owner, HIR_ID_COUNTER_LOCKED)
.unwrap();
let def_index = self.resolver.definitions().opt_def_index(owner).unwrap();
self.current_hir_id_owner.push((def_index, counter));
f(self);
@@ -440,7 +505,9 @@ fn with_hir_id_owner<F>(&mut self, owner: NodeId, f: F)
debug_assert!(def_index == new_def_index);
debug_assert!(new_counter >= counter);
let prev = self.item_local_id_counters.insert(owner, new_counter).unwrap();
let prev = self.item_local_id_counters
.insert(owner, new_counter)
.unwrap();
debug_assert!(prev == HIR_ID_COUNTER_LOCKED);
}
@@ -452,9 +519,8 @@ fn with_hir_id_owner<F>(&mut self, owner: NodeId, f: F)
/// properly. Calling the method twice with the same NodeId is fine though.
fn lower_node_id(&mut self, ast_node_id: NodeId) -> LoweredNodeId {
self.lower_node_id_generic(ast_node_id, |this| {
let &mut (def_index, ref mut local_id_counter) = this.current_hir_id_owner
.last_mut()
.unwrap();
let &mut (def_index, ref mut local_id_counter) =
this.current_hir_id_owner.last_mut().unwrap();
let local_id = *local_id_counter;
*local_id_counter += 1;
hir::HirId {
@@ -464,14 +530,9 @@ fn lower_node_id(&mut self, ast_node_id: NodeId) -> LoweredNodeId {
})
}
fn lower_node_id_with_owner(&mut self,
ast_node_id: NodeId,
owner: NodeId)
-> LoweredNodeId {
fn lower_node_id_with_owner(&mut self, ast_node_id: NodeId, owner: NodeId) -> LoweredNodeId {
self.lower_node_id_generic(ast_node_id, |this| {
let local_id_counter = this.item_local_id_counters
.get_mut(&owner)
.unwrap();
let local_id_counter = this.item_local_id_counters.get_mut(&owner).unwrap();
let local_id = *local_id_counter;
// We want to be sure not to modify the counter in the map while it
@@ -489,8 +550,7 @@ fn lower_node_id_with_owner(&mut self,
})
}
fn record_body(&mut self, value: hir::Expr, decl: Option<&FnDecl>)
-> hir::BodyId {
fn record_body(&mut self, value: hir::Expr, decl: Option<&FnDecl>) -> hir::BodyId {
let body = hir::Body {
arguments: decl.map_or(hir_vec![], |decl| {
decl.inputs.iter().map(|x| self.lower_arg(x)).collect()
@@ -524,8 +584,7 @@ fn str_to_ident(&self, s: &'static str) -> Name {
Symbol::gensym(s)
}
fn allow_internal_unstable(&self, reason: CompilerDesugaringKind, span: Span) -> Span
{
fn allow_internal_unstable(&self, reason: CompilerDesugaringKind, span: Span) -> Span {
let mark = Mark::fresh(Mark::root());
mark.set_expn_info(codemap::ExpnInfo {
call_site: span,
@@ -539,73 +598,139 @@ fn allow_internal_unstable(&self, reason: CompilerDesugaringKind, span: Span) ->
span.with_ctxt(SyntaxContext::empty().apply_mark(mark))
}
// Creates a new hir::GenericParam for every new lifetime and type parameter
// encountered while evaluating `f`. Definitions are created with the parent
// provided. If no `parent_id` is provided, no definitions will be returned.
/// Creates a new hir::GenericParam for every new lifetime and
/// type parameter encountered while evaluating `f`. Definitions
/// are created with the parent provided. If no `parent_id` is
/// provided, no definitions will be returned.
///
/// Presuming that in-band lifetimes are enabled, then
/// `self.anonymous_lifetime_mode` will be updated to match the
/// argument while `f` is running (and restored afterwards).
fn collect_in_band_defs<T, F>(
&mut self,
parent_id: Option<DefId>,
f: F
) -> (Vec<hir::GenericParam>, T) where F: FnOnce(&mut LoweringContext) -> T
parent_id: DefId,
anonymous_lifetime_mode: AnonymousLifetimeMode,
f: F,
) -> (Vec<hir::GenericParam>, T)
where
F: FnOnce(&mut LoweringContext) -> T,
{
assert!(!self.is_collecting_in_band_lifetimes);
assert!(self.lifetimes_to_define.is_empty());
let old_anonymous_lifetime_mode = self.anonymous_lifetime_mode;
self.is_collecting_in_band_lifetimes = self.sess.features_untracked().in_band_lifetimes;
if self.is_collecting_in_band_lifetimes {
self.anonymous_lifetime_mode = anonymous_lifetime_mode;
}
assert!(self.in_band_ty_params.is_empty());
let res = f(self);
self.is_collecting_in_band_lifetimes = false;
self.anonymous_lifetime_mode = old_anonymous_lifetime_mode;
let in_band_ty_params = self.in_band_ty_params.split_off(0);
let lifetimes_to_define = self.lifetimes_to_define.split_off(0);
let mut params = match parent_id {
Some(parent_id) => lifetimes_to_define.into_iter().map(|(span, name)| {
let def_node_id = self.next_id().node_id;
let params = lifetimes_to_define
.into_iter()
.map(|(span, hir_name)| {
let def_node_id = self.next_id().node_id;
// Add a definition for the in-band lifetime def
self.resolver.definitions().create_def_with_parent(
parent_id.index,
def_node_id,
DefPathData::LifetimeDef(name.as_str()),
DefIndexAddressSpace::High,
Mark::root(),
span
);
// Get the name we'll use to make the def-path. Note
// that collisions are ok here and this shouldn't
// really show up for end-user.
let str_name = match hir_name {
hir::LifetimeName::Name(n) => n.as_str(),
hir::LifetimeName::Fresh(_) => keywords::UnderscoreLifetime.name().as_str(),
hir::LifetimeName::Implicit
| hir::LifetimeName::Underscore
| hir::LifetimeName::Static => {
span_bug!(span, "unexpected in-band lifetime name: {:?}", hir_name)
}
};
hir::GenericParam::Lifetime(hir::LifetimeDef {
lifetime: hir::Lifetime {
id: def_node_id,
span,
name: hir::LifetimeName::Name(name),
},
bounds: Vec::new().into(),
pure_wrt_drop: false,
in_band: true,
})
}).collect(),
None => Vec::new(),
};
// Add a definition for the in-band lifetime def
self.resolver.definitions().create_def_with_parent(
parent_id.index,
def_node_id,
DefPathData::LifetimeDef(str_name),
DefIndexAddressSpace::High,
Mark::root(),
span,
);
params.extend(in_band_ty_params.into_iter().map(|tp| hir::GenericParam::Type(tp)));
hir::GenericParam::Lifetime(hir::LifetimeDef {
lifetime: hir::Lifetime {
id: def_node_id,
span,
name: hir_name,
},
bounds: Vec::new().into(),
pure_wrt_drop: false,
in_band: true,
})
})
.chain(
in_band_ty_params
.into_iter()
.map(|tp| hir::GenericParam::Type(tp)),
)
.collect();
(params, res)
}
/// When there is a reference to some lifetime `'a`, and in-band
/// lifetimes are enabled, then we want to push that lifetime into
/// the vector of names to define later. In that case, it will get
/// added to the appropriate generics.
fn maybe_collect_in_band_lifetime(&mut self, span: Span, name: Name) {
if !self.is_collecting_in_band_lifetimes {
return;
}
if self.in_scope_lifetimes.contains(&name) {
return;
}
let hir_name = hir::LifetimeName::Name(name);
if self.lifetimes_to_define
.iter()
.any(|(_, lt_name)| *lt_name == hir_name)
{
return;
}
self.lifetimes_to_define.push((span, hir_name));
}
/// When we have either an elided or `'_` lifetime in an impl
/// header, we convert it to
fn collect_fresh_in_band_lifetime(&mut self, span: Span) -> hir::LifetimeName {
assert!(self.is_collecting_in_band_lifetimes);
let index = self.lifetimes_to_define.len();
let hir_name = hir::LifetimeName::Fresh(index);
self.lifetimes_to_define.push((span, hir_name));
hir_name
}
// Evaluates `f` with the lifetimes in `lt_defs` in-scope.
// This is used to track which lifetimes have already been defined, and
// which are new in-band lifetimes that need to have a definition created
// for them.
fn with_in_scope_lifetime_defs<T, F>(
fn with_in_scope_lifetime_defs<'l, T, F>(
&mut self,
lt_defs: &[LifetimeDef],
f: F
) -> T where F: FnOnce(&mut LoweringContext) -> T
lt_defs: impl Iterator<Item = &'l LifetimeDef>,
f: F,
) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let old_len = self.in_scope_lifetimes.len();
let lt_def_names = lt_defs.iter().map(|lt_def| lt_def.lifetime.ident.name);
let lt_def_names = lt_defs.map(|lt_def| lt_def.lifetime.ident.name);
self.in_scope_lifetimes.extend(lt_def_names);
let res = f(self);
@@ -619,11 +744,9 @@ fn with_in_scope_lifetime_defs<T, F>(
// This should only be used with generics that have already had their
// in-band lifetimes added. In practice, this means that this function is
// only used when lowering a child item of a trait or impl.
fn with_parent_impl_lifetime_defs<T, F>(
&mut self,
lt_defs: &[hir::LifetimeDef],
f: F
) -> T where F: FnOnce(&mut LoweringContext) -> T
fn with_parent_impl_lifetime_defs<T, F>(&mut self, lt_defs: &[hir::LifetimeDef], f: F) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let old_len = self.in_scope_lifetimes.len();
let lt_def_names = lt_defs.iter().map(|lt_def| lt_def.lifetime.name.name());
@@ -635,47 +758,57 @@ fn with_parent_impl_lifetime_defs<T, F>(
res
}
// Appends in-band lifetime defs and argument-position `impl Trait` defs
// to the existing set of generics.
/// Appends in-band lifetime defs and argument-position `impl
/// Trait` defs to the existing set of generics.
///
/// Presuming that in-band lifetimes are enabled, then
/// `self.anonymous_lifetime_mode` will be updated to match the
/// argument while `f` is running (and restored afterwards).
fn add_in_band_defs<F, T>(
&mut self,
generics: &Generics,
parent_id: Option<DefId>,
f: F
parent_id: DefId,
anonymous_lifetime_mode: AnonymousLifetimeMode,
f: F,
) -> (hir::Generics, T)
where F: FnOnce(&mut LoweringContext) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let (in_band_defs, (mut lowered_generics, res)) =
self.with_in_scope_lifetime_defs(
&generics.params
.iter()
.filter_map(|p| match *p {
GenericParam::Lifetime(ref ld) => Some(ld.clone()),
_ => None,
})
.collect::<Vec<_>>(),
|this| {
this.collect_in_band_defs(parent_id, |this| {
(this.lower_generics(generics), f(this))
})
}
);
let (in_band_defs, (mut lowered_generics, res)) = self.with_in_scope_lifetime_defs(
generics.params.iter().filter_map(|p| match p {
GenericParam::Lifetime(ld) => Some(ld),
_ => None,
}),
|this| {
this.collect_in_band_defs(parent_id, anonymous_lifetime_mode, |this| {
(this.lower_generics(generics), f(this))
})
},
);
lowered_generics.params =
lowered_generics.params.iter().cloned().chain(in_band_defs).collect();
lowered_generics.params = lowered_generics
.params
.iter()
.cloned()
.chain(in_band_defs)
.collect();
(lowered_generics, res)
}
fn with_catch_scope<T, F>(&mut self, catch_id: NodeId, f: F) -> T
where F: FnOnce(&mut LoweringContext) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let len = self.catch_scopes.len();
self.catch_scopes.push(catch_id);
let result = f(self);
assert_eq!(len + 1, self.catch_scopes.len(),
"catch scopes should be added and removed in stack order");
assert_eq!(
len + 1,
self.catch_scopes.len(),
"catch scopes should be added and removed in stack order"
);
self.catch_scopes.pop().unwrap();
@@ -683,17 +816,19 @@ fn with_catch_scope<T, F>(&mut self, catch_id: NodeId, f: F) -> T
}
fn lower_body<F>(&mut self, decl: Option<&FnDecl>, f: F) -> hir::BodyId
where F: FnOnce(&mut LoweringContext) -> hir::Expr
where
F: FnOnce(&mut LoweringContext) -> hir::Expr,
{
let prev = mem::replace(&mut self.is_generator, false);
let result = f(self);
let r = self.record_body(result, decl);
self.is_generator = prev;
return r
return r;
}
fn with_loop_scope<T, F>(&mut self, loop_id: NodeId, f: F) -> T
where F: FnOnce(&mut LoweringContext) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
// We're no longer in the base loop's condition; we're in another loop.
let was_in_loop_condition = self.is_in_loop_condition;
@@ -703,8 +838,11 @@ fn with_loop_scope<T, F>(&mut self, loop_id: NodeId, f: F) -> T
self.loop_scopes.push(loop_id);
let result = f(self);
assert_eq!(len + 1, self.loop_scopes.len(),
"Loop scopes should be added and removed in stack order");
assert_eq!(
len + 1,
self.loop_scopes.len(),
"Loop scopes should be added and removed in stack order"
);
self.loop_scopes.pop().unwrap();
@@ -714,7 +852,8 @@ fn with_loop_scope<T, F>(&mut self, loop_id: NodeId, f: F) -> T
}
fn with_loop_condition_scope<T, F>(&mut self, f: F) -> T
where F: FnOnce(&mut LoweringContext) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let was_in_loop_condition = self.is_in_loop_condition;
self.is_in_loop_condition = true;
@@ -727,7 +866,8 @@ fn with_loop_condition_scope<T, F>(&mut self, f: F) -> T
}
fn with_new_scopes<T, F>(&mut self, f: F) -> T
where F: FnOnce(&mut LoweringContext) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let was_in_loop_condition = self.is_in_loop_condition;
self.is_in_loop_condition = false;
@@ -744,7 +884,8 @@ fn with_new_scopes<T, F>(&mut self, f: F) -> T
}
fn with_parent_def<T, F>(&mut self, parent_id: NodeId, f: F) -> T
where F: FnOnce(&mut LoweringContext) -> T
where
F: FnOnce(&mut LoweringContext) -> T,
{
let old_def = self.parent_def;
self.parent_def = {
@@ -771,16 +912,19 @@ fn lower_ident(&mut self, ident: Ident) -> Name {
if ident.ctxt == SyntaxContext::empty() {
return ident.name;
}
*self.name_map.entry(ident).or_insert_with(|| Symbol::from_ident(ident))
*self.name_map
.entry(ident)
.or_insert_with(|| Symbol::from_ident(ident))
}
fn lower_label(&mut self, label: Option<Label>) -> Option<hir::Label> {
label.map(|label| hir::Label { name: label.ident.name, span: label.span })
label.map(|label| hir::Label {
name: label.ident.name,
span: label.span,
})
}
fn lower_loop_destination(&mut self, destination: Option<(NodeId, Label)>)
-> hir::Destination
{
fn lower_loop_destination(&mut self, destination: Option<(NodeId, Label)>) -> hir::Destination {
match destination {
Some((id, label)) => {
let target = if let Def::Label(loop_id) = self.expect_full_def(id) {
@@ -792,25 +936,31 @@ fn lower_loop_destination(&mut self, destination: Option<(NodeId, Label)>)
label: self.lower_label(Some(label)),
target_id: hir::ScopeTarget::Loop(target),
}
},
}
None => {
let loop_id = self.loop_scopes
.last()
.map(|innermost_loop_id| *innermost_loop_id);
.last()
.map(|innermost_loop_id| *innermost_loop_id);
hir::Destination {
label: None,
target_id: hir::ScopeTarget::Loop(
loop_id.map(|id| Ok(self.lower_node_id(id).node_id))
.unwrap_or(Err(hir::LoopIdError::OutsideLoopScope))
.into())
loop_id
.map(|id| Ok(self.lower_node_id(id).node_id))
.unwrap_or(Err(hir::LoopIdError::OutsideLoopScope))
.into(),
),
}
}
}
}
fn lower_attrs(&mut self, attrs: &[Attribute]) -> hir::HirVec<Attribute> {
attrs.iter().map(|a| self.lower_attr(a)).collect::<Vec<_>>().into()
attrs
.iter()
.map(|a| self.lower_attr(a))
.collect::<Vec<_>>()
.into()
}
fn lower_attr(&mut self, attr: &Attribute) -> Attribute {
@@ -825,22 +975,22 @@ fn lower_attr(&mut self, attr: &Attribute) -> Attribute {
}
fn lower_token_stream(&mut self, tokens: TokenStream) -> TokenStream {
tokens.into_trees()
tokens
.into_trees()
.flat_map(|tree| self.lower_token_tree(tree).into_trees())
.collect()
}
fn lower_token_tree(&mut self, tree: TokenTree) -> TokenStream {
match tree {
TokenTree::Token(span, token) => {
self.lower_token(token, span)
}
TokenTree::Delimited(span, delimited) => {
TokenTree::Delimited(span, Delimited {
TokenTree::Token(span, token) => self.lower_token(token, span),
TokenTree::Delimited(span, delimited) => TokenTree::Delimited(
span,
Delimited {
delim: delimited.delim,
tts: self.lower_token_stream(delimited.tts.into()).into(),
}).into()
}
},
).into(),
}
}
@@ -882,27 +1032,25 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
let span = t.span.shrink_to_lo();
let lifetime = match *region {
Some(ref lt) => self.lower_lifetime(lt),
None => self.elided_lifetime(span)
None => self.elided_ref_lifetime(span),
};
hir::TyRptr(lifetime, self.lower_mt(mt, itctx))
}
TyKind::BareFn(ref f) => {
self.with_in_scope_lifetime_defs(
&f.generic_params
.iter()
.filter_map(|p| match *p {
GenericParam::Lifetime(ref ld) => Some(ld.clone()),
_ => None,
})
.collect::<Vec<_>>(),
|this| hir::TyBareFn(P(hir::BareFnTy {
TyKind::BareFn(ref f) => self.with_in_scope_lifetime_defs(
f.generic_params.iter().filter_map(|p| match p {
GenericParam::Lifetime(ld) => Some(ld),
_ => None,
}),
|this| {
hir::TyBareFn(P(hir::BareFnTy {
generic_params: this.lower_generic_params(&f.generic_params, &NodeMap()),
unsafety: this.lower_unsafety(f.unsafety),
abi: f.abi,
decl: this.lower_fn_decl(&f.decl, None, false),
arg_names: this.lower_fn_args_to_names(&f.decl),
})))
}
}))
},
),
TyKind::Never => hir::TyNever,
TyKind::Tup(ref tys) => {
hir::TyTup(tys.iter().map(|ty| self.lower_ty(ty, itctx)).collect())
@@ -919,15 +1067,14 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
}
return ty;
}
TyKind::ImplicitSelf => {
hir::TyPath(hir::QPath::Resolved(None, P(hir::Path {
TyKind::ImplicitSelf => hir::TyPath(hir::QPath::Resolved(
None,
P(hir::Path {
def: self.expect_full_def(t.id),
segments: hir_vec![
hir::PathSegment::from_name(keywords::SelfType.name())
],
segments: hir_vec![hir::PathSegment::from_name(keywords::SelfType.name())],
span: t.span,
})))
}
}),
)),
TyKind::Array(ref ty, ref length) => {
let length = self.lower_body(None, |this| this.lower_expr(length));
hir::TyArray(self.lower_ty(ty, itctx), length)
@@ -938,8 +1085,9 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
}
TyKind::TraitObject(ref bounds, kind) => {
let mut lifetime_bound = None;
let bounds = bounds.iter().filter_map(|bound| {
match *bound {
let bounds = bounds
.iter()
.filter_map(|bound| match *bound {
TraitTyParamBound(ref ty, TraitBoundModifier::None) => {
Some(self.lower_poly_trait_ref(ty, itctx))
}
@@ -950,11 +1098,10 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
}
None
}
}
}).collect();
let lifetime_bound = lifetime_bound.unwrap_or_else(|| {
self.elided_lifetime(t.span)
});
})
.collect();
let lifetime_bound =
lifetime_bound.unwrap_or_else(|| self.elided_dyn_bound(t.span));
if kind != TraitObjectSyntax::Dyn {
self.maybe_lint_bare_trait(t.span, t.id, false);
}
@@ -967,33 +1114,44 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
ImplTraitContext::Existential => {
let has_feature = self.sess.features_untracked().conservative_impl_trait;
if !t.span.allows_unstable() && !has_feature {
emit_feature_err(&self.sess.parse_sess, "conservative_impl_trait",
t.span, GateIssue::Language,
"`impl Trait` in return position is experimental");
emit_feature_err(
&self.sess.parse_sess,
"conservative_impl_trait",
t.span,
GateIssue::Language,
"`impl Trait` in return position is experimental",
);
}
let def_index = self.resolver.definitions().opt_def_index(t.id).unwrap();
let hir_bounds = self.lower_bounds(bounds, itctx);
let (lifetimes, lifetime_defs) =
self.lifetimes_from_impl_trait_bounds(def_index, &hir_bounds);
hir::TyImplTraitExistential(hir::ExistTy {
generics: hir::Generics {
params: lifetime_defs,
where_clause: hir::WhereClause {
id: self.next_id().node_id,
predicates: Vec::new().into(),
hir::TyImplTraitExistential(
hir::ExistTy {
generics: hir::Generics {
params: lifetime_defs,
where_clause: hir::WhereClause {
id: self.next_id().node_id,
predicates: Vec::new().into(),
},
span,
},
span,
bounds: hir_bounds,
},
bounds: hir_bounds,
}, lifetimes)
},
lifetimes,
)
}
ImplTraitContext::Universal(def_id) => {
let has_feature = self.sess.features_untracked().universal_impl_trait;
if !t.span.allows_unstable() && !has_feature {
emit_feature_err(&self.sess.parse_sess, "universal_impl_trait",
t.span, GateIssue::Language,
"`impl Trait` in argument position is experimental");
emit_feature_err(
&self.sess.parse_sess,
"universal_impl_trait",
t.span,
GateIssue::Language,
"`impl Trait` in argument position is experimental",
);
}
let def_node_id = self.next_id().node_id;
@@ -1005,7 +1163,7 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
DefPathData::ImplTrait,
DefIndexAddressSpace::High,
Mark::root(),
span
span,
);
let hir_bounds = self.lower_bounds(bounds, itctx);
@@ -1022,16 +1180,23 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
attrs: P::new(),
});
hir::TyPath(hir::QPath::Resolved(None, P(hir::Path {
span,
def: Def::TyParam(DefId::local(def_index)),
segments: hir_vec![hir::PathSegment::from_name(name)],
})))
},
hir::TyPath(hir::QPath::Resolved(
None,
P(hir::Path {
span,
def: Def::TyParam(DefId::local(def_index)),
segments: hir_vec![hir::PathSegment::from_name(name)],
}),
))
}
ImplTraitContext::Disallowed => {
span_err!(self.sess, t.span, E0562,
"`impl Trait` not allowed outside of function \
and inherent method return types");
span_err!(
self.sess,
t.span,
E0562,
"`impl Trait` not allowed outside of function \
and inherent method return types"
);
hir::TyErr
}
}
@@ -1051,9 +1216,8 @@ fn lower_ty(&mut self, t: &Ty, itctx: ImplTraitContext) -> P<hir::Ty> {
fn lifetimes_from_impl_trait_bounds(
&mut self,
parent_index: DefIndex,
bounds: &hir::TyParamBounds
bounds: &hir::TyParamBounds,
) -> (HirVec<hir::Lifetime>, HirVec<hir::GenericParam>) {
// This visitor walks over impl trait bounds and creates defs for all lifetimes which
// appear in the bounds, excluding lifetimes that are created within the bounds.
// e.g. 'a, 'b, but not 'c in `impl for<'c> SomeTrait<'a, 'b, 'c>`
@@ -1068,8 +1232,9 @@ struct ImplTraitLifetimeCollector<'r, 'a: 'r> {
}
impl<'r, 'a: 'r, 'v> hir::intravisit::Visitor<'v> for ImplTraitLifetimeCollector<'r, 'a> {
fn nested_visit_map<'this>(&'this mut self)
-> hir::intravisit::NestedVisitorMap<'this, 'v> {
fn nested_visit_map<'this>(
&'this mut self,
) -> hir::intravisit::NestedVisitorMap<'this, 'v> {
hir::intravisit::NestedVisitorMap::None
}
@@ -1097,9 +1262,11 @@ fn visit_ty(&mut self, t: &'v hir::Ty) {
}
}
fn visit_poly_trait_ref(&mut self,
polytr: &'v hir::PolyTraitRef,
_: hir::TraitBoundModifier) {
fn visit_poly_trait_ref(
&mut self,
polytr: &'v hir::PolyTraitRef,
_: hir::TraitBoundModifier,
) {
let old_len = self.currently_bound_lifetimes.len();
// Record the introduction of 'a in `for<'a> ...`
@@ -1123,21 +1290,22 @@ fn visit_poly_trait_ref(&mut self,
fn visit_lifetime(&mut self, lifetime: &'v hir::Lifetime) {
let name = match lifetime.name {
hir::LifetimeName::Implicit |
hir::LifetimeName::Underscore =>
hir::LifetimeName::Implicit | hir::LifetimeName::Underscore => {
if self.collect_elided_lifetimes {
// Use `'_` for both implicit and underscore lifetimes in
// `abstract type Foo<'_>: SomeTrait<'_>;`
hir::LifetimeName::Underscore
} else {
return
return;
}
}
name @ hir::LifetimeName::Fresh(_) => name,
name @ hir::LifetimeName::Name(_) => name,
hir::LifetimeName::Static => return,
};
if !self.currently_bound_lifetimes.contains(&name) &&
!self.already_defined_lifetimes.contains(&name)
if !self.currently_bound_lifetimes.contains(&name)
&& !self.already_defined_lifetimes.contains(&name)
{
self.already_defined_lifetimes.insert(name);
@@ -1154,19 +1322,20 @@ fn visit_lifetime(&mut self, lifetime: &'v hir::Lifetime) {
DefPathData::LifetimeDef(name.name().as_str()),
DefIndexAddressSpace::High,
Mark::root(),
lifetime.span
lifetime.span,
);
let def_lifetime = hir::Lifetime {
id: def_node_id,
span: lifetime.span,
name: name,
};
self.output_lifetime_params.push(hir::GenericParam::Lifetime(hir::LifetimeDef {
lifetime: def_lifetime,
bounds: Vec::new().into(),
pure_wrt_drop: false,
in_band: false,
}));
self.output_lifetime_params
.push(hir::GenericParam::Lifetime(hir::LifetimeDef {
lifetime: def_lifetime,
bounds: Vec::new().into(),
pure_wrt_drop: false,
in_band: false,
}));
}
}
}
@@ -1187,14 +1356,17 @@ fn visit_lifetime(&mut self, lifetime: &'v hir::Lifetime) {
(
lifetime_collector.output_lifetimes.into(),
lifetime_collector.output_lifetime_params.into()
lifetime_collector.output_lifetime_params.into(),
)
}
fn lower_foreign_mod(&mut self, fm: &ForeignMod) -> hir::ForeignMod {
hir::ForeignMod {
abi: fm.abi,
items: fm.items.iter().map(|x| self.lower_foreign_item(x)).collect(),
items: fm.items
.iter()
.map(|x| self.lower_foreign_item(x))
.collect(),
}
}
@@ -1211,94 +1383,116 @@ fn lower_variant(&mut self, v: &Variant) -> hir::Variant {
name: v.node.name.name,
attrs: self.lower_attrs(&v.node.attrs),
data: self.lower_variant_data(&v.node.data),
disr_expr: v.node.disr_expr.as_ref().map(|e| {
self.lower_body(None, |this| this.lower_expr(e))
}),
disr_expr: v.node
.disr_expr
.as_ref()
.map(|e| self.lower_body(None, |this| this.lower_expr(e))),
},
span: v.span,
}
}
fn lower_qpath(&mut self,
id: NodeId,
qself: &Option<QSelf>,
p: &Path,
param_mode: ParamMode,
itctx: ImplTraitContext)
-> hir::QPath {
fn lower_qpath(
&mut self,
id: NodeId,
qself: &Option<QSelf>,
p: &Path,
param_mode: ParamMode,
itctx: ImplTraitContext,
) -> hir::QPath {
let qself_position = qself.as_ref().map(|q| q.position);
let qself = qself.as_ref().map(|q| self.lower_ty(&q.ty, itctx));
let resolution = self.resolver.get_resolution(id)
.unwrap_or(PathResolution::new(Def::Err));
let resolution = self.resolver
.get_resolution(id)
.unwrap_or(PathResolution::new(Def::Err));
let proj_start = p.segments.len() - resolution.unresolved_segments();
let path = P(hir::Path {
def: resolution.base_def(),
segments: p.segments[..proj_start].iter().enumerate().map(|(i, segment)| {
let param_mode = match (qself_position, param_mode) {
(Some(j), ParamMode::Optional) if i < j => {
// This segment is part of the trait path in a
// qualified path - one of `a`, `b` or `Trait`
// in `<X as a::b::Trait>::T::U::method`.
ParamMode::Explicit
}
_ => param_mode
};
segments: p.segments[..proj_start]
.iter()
.enumerate()
.map(|(i, segment)| {
let param_mode = match (qself_position, param_mode) {
(Some(j), ParamMode::Optional) if i < j => {
// This segment is part of the trait path in a
// qualified path - one of `a`, `b` or `Trait`
// in `<X as a::b::Trait>::T::U::method`.
ParamMode::Explicit
}
_ => param_mode,
};
// Figure out if this is a type/trait segment,
// which may need lifetime elision performed.
let parent_def_id = |this: &mut Self, def_id: DefId| {
DefId {
// Figure out if this is a type/trait segment,
// which may need lifetime elision performed.
let parent_def_id = |this: &mut Self, def_id: DefId| DefId {
krate: def_id.krate,
index: this.def_key(def_id).parent.expect("missing parent")
}
};
let type_def_id = match resolution.base_def() {
Def::AssociatedTy(def_id) if i + 2 == proj_start => {
Some(parent_def_id(self, def_id))
}
Def::Variant(def_id) if i + 1 == proj_start => {
Some(parent_def_id(self, def_id))
}
Def::Struct(def_id) |
Def::Union(def_id) |
Def::Enum(def_id) |
Def::TyAlias(def_id) |
Def::Trait(def_id) if i + 1 == proj_start => Some(def_id),
_ => None
};
let parenthesized_generic_args = match resolution.base_def() {
// `a::b::Trait(Args)`
Def::Trait(..) if i + 1 == proj_start => ParenthesizedGenericArgs::Ok,
// `a::b::Trait(Args)::TraitItem`
Def::Method(..) |
Def::AssociatedConst(..) |
Def::AssociatedTy(..) if i + 2 == proj_start => ParenthesizedGenericArgs::Ok,
// Avoid duplicated errors
Def::Err => ParenthesizedGenericArgs::Ok,
// An error
Def::Struct(..) | Def::Enum(..) | Def::Union(..) | Def::TyAlias(..) |
Def::Variant(..) if i + 1 == proj_start => ParenthesizedGenericArgs::Err,
// A warning for now, for compatibility reasons
_ => ParenthesizedGenericArgs::Warn,
};
index: this.def_key(def_id).parent.expect("missing parent"),
};
let type_def_id = match resolution.base_def() {
Def::AssociatedTy(def_id) if i + 2 == proj_start => {
Some(parent_def_id(self, def_id))
}
Def::Variant(def_id) if i + 1 == proj_start => {
Some(parent_def_id(self, def_id))
}
Def::Struct(def_id)
| Def::Union(def_id)
| Def::Enum(def_id)
| Def::TyAlias(def_id)
| Def::Trait(def_id) if i + 1 == proj_start =>
{
Some(def_id)
}
_ => None,
};
let parenthesized_generic_args = match resolution.base_def() {
// `a::b::Trait(Args)`
Def::Trait(..) if i + 1 == proj_start => ParenthesizedGenericArgs::Ok,
// `a::b::Trait(Args)::TraitItem`
Def::Method(..) | Def::AssociatedConst(..) | Def::AssociatedTy(..)
if i + 2 == proj_start =>
{
ParenthesizedGenericArgs::Ok
}
// Avoid duplicated errors
Def::Err => ParenthesizedGenericArgs::Ok,
// An error
Def::Struct(..)
| Def::Enum(..)
| Def::Union(..)
| Def::TyAlias(..)
| Def::Variant(..) if i + 1 == proj_start =>
{
ParenthesizedGenericArgs::Err
}
// A warning for now, for compatibility reasons
_ => ParenthesizedGenericArgs::Warn,
};
let num_lifetimes = type_def_id.map_or(0, |def_id| {
if let Some(&n) = self.type_def_lifetime_params.get(&def_id) {
return n;
}
assert!(!def_id.is_local());
let n = self.cstore
.item_generics_cloned_untracked(def_id, self.sess)
.regions
.len();
self.type_def_lifetime_params.insert(def_id, n);
n
});
self.lower_path_segment(p.span, segment, param_mode, num_lifetimes,
parenthesized_generic_args, itctx)
}).collect(),
let num_lifetimes = type_def_id.map_or(0, |def_id| {
if let Some(&n) = self.type_def_lifetime_params.get(&def_id) {
return n;
}
assert!(!def_id.is_local());
let n = self.cstore
.item_generics_cloned_untracked(def_id, self.sess)
.regions
.len();
self.type_def_lifetime_params.insert(def_id, n);
n
});
self.lower_path_segment(
p.span,
segment,
param_mode,
num_lifetimes,
parenthesized_generic_args,
itctx,
)
})
.collect(),
span: p.span,
});
@@ -1332,9 +1526,14 @@ fn lower_qpath(&mut self,
// 3. `<<std::vec::Vec<T>>::IntoIter>::Item`
// * final path is `<<<std::vec::Vec<T>>::IntoIter>::Item>::clone`
for (i, segment) in p.segments.iter().enumerate().skip(proj_start) {
let segment = P(self.lower_path_segment(p.span, segment, param_mode, 0,
ParenthesizedGenericArgs::Warn,
itctx));
let segment = P(self.lower_path_segment(
p.span,
segment,
param_mode,
0,
ParenthesizedGenericArgs::Warn,
itctx,
));
let qpath = hir::QPath::TypeRelative(ty, segment);
// It's finished, return the extension of the right node type.
@@ -1348,44 +1547,54 @@ fn lower_qpath(&mut self,
}
// Should've returned in the for loop above.
span_bug!(p.span, "lower_qpath: no final extension segment in {}..{}",
proj_start, p.segments.len())
span_bug!(
p.span,
"lower_qpath: no final extension segment in {}..{}",
proj_start,
p.segments.len()
)
}
fn lower_path_extra(&mut self,
id: NodeId,
p: &Path,
name: Option<Name>,
param_mode: ParamMode)
-> hir::Path {
fn lower_path_extra(
&mut self,
id: NodeId,
p: &Path,
name: Option<Name>,
param_mode: ParamMode,
) -> hir::Path {
hir::Path {
def: self.expect_full_def(id),
segments: p.segments.iter().map(|segment| {
self.lower_path_segment(p.span, segment, param_mode, 0,
ParenthesizedGenericArgs::Err,
ImplTraitContext::Disallowed)
}).chain(name.map(|name| hir::PathSegment::from_name(name)))
.collect(),
segments: p.segments
.iter()
.map(|segment| {
self.lower_path_segment(
p.span,
segment,
param_mode,
0,
ParenthesizedGenericArgs::Err,
ImplTraitContext::Disallowed,
)
})
.chain(name.map(|name| hir::PathSegment::from_name(name)))
.collect(),
span: p.span,
}
}
fn lower_path(&mut self,
id: NodeId,
p: &Path,
param_mode: ParamMode)
-> hir::Path {
fn lower_path(&mut self, id: NodeId, p: &Path, param_mode: ParamMode) -> hir::Path {
self.lower_path_extra(id, p, None, param_mode)
}
fn lower_path_segment(&mut self,
path_span: Span,
segment: &PathSegment,
param_mode: ParamMode,
expected_lifetimes: usize,
parenthesized_generic_args: ParenthesizedGenericArgs,
itctx: ImplTraitContext)
-> hir::PathSegment {
fn lower_path_segment(
&mut self,
path_span: Span,
segment: &PathSegment,
param_mode: ParamMode,
expected_lifetimes: usize,
parenthesized_generic_args: ParenthesizedGenericArgs,
itctx: ImplTraitContext,
) -> hir::PathSegment {
let (mut parameters, infer_types) = if let Some(ref parameters) = segment.parameters {
let msg = "parenthesized parameters may only be used with a trait";
match **parameters {
@@ -1393,74 +1602,108 @@ fn lower_path_segment(&mut self,
self.lower_angle_bracketed_parameter_data(data, param_mode, itctx)
}
PathParameters::Parenthesized(ref data) => match parenthesized_generic_args {
ParenthesizedGenericArgs::Ok =>
self.lower_parenthesized_parameter_data(data),
ParenthesizedGenericArgs::Ok => self.lower_parenthesized_parameter_data(data),
ParenthesizedGenericArgs::Warn => {
self.sess.buffer_lint(PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES,
CRATE_NODE_ID, data.span, msg.into());
self.sess.buffer_lint(
PARENTHESIZED_PARAMS_IN_TYPES_AND_MODULES,
CRATE_NODE_ID,
data.span,
msg.into(),
);
(hir::PathParameters::none(), true)
}
ParenthesizedGenericArgs::Err => {
struct_span_err!(self.sess, data.span, E0214, "{}", msg)
.span_label(data.span, "only traits may use parentheses").emit();
.span_label(data.span, "only traits may use parentheses")
.emit();
(hir::PathParameters::none(), true)
}
}
},
}
} else {
self.lower_angle_bracketed_parameter_data(&Default::default(), param_mode, itctx)
};
if !parameters.parenthesized && parameters.lifetimes.is_empty() {
parameters.lifetimes = (0..expected_lifetimes).map(|_| {
self.elided_lifetime(path_span)
}).collect();
parameters.lifetimes = self.elided_path_lifetimes(path_span, expected_lifetimes);
}
hir::PathSegment::new(
self.lower_ident(segment.identifier),
parameters,
infer_types
infer_types,
)
}
fn lower_angle_bracketed_parameter_data(&mut self,
data: &AngleBracketedParameterData,
param_mode: ParamMode,
itctx: ImplTraitContext)
-> (hir::PathParameters, bool) {
let &AngleBracketedParameterData { ref lifetimes, ref types, ref bindings, .. } = data;
(hir::PathParameters {
lifetimes: self.lower_lifetimes(lifetimes),
types: types.iter().map(|ty| self.lower_ty(ty, itctx)).collect(),
bindings: bindings.iter().map(|b| self.lower_ty_binding(b, itctx)).collect(),
parenthesized: false,
}, types.is_empty() && param_mode == ParamMode::Optional)
fn lower_angle_bracketed_parameter_data(
&mut self,
data: &AngleBracketedParameterData,
param_mode: ParamMode,
itctx: ImplTraitContext,
) -> (hir::PathParameters, bool) {
let &AngleBracketedParameterData {
ref lifetimes,
ref types,
ref bindings,
..
} = data;
(
hir::PathParameters {
lifetimes: self.lower_lifetimes(lifetimes),
types: types.iter().map(|ty| self.lower_ty(ty, itctx)).collect(),
bindings: bindings
.iter()
.map(|b| self.lower_ty_binding(b, itctx))
.collect(),
parenthesized: false,
},
types.is_empty() && param_mode == ParamMode::Optional,
)
}
fn lower_parenthesized_parameter_data(&mut self,
data: &ParenthesizedParameterData)
-> (hir::PathParameters, bool) {
fn lower_parenthesized_parameter_data(
&mut self,
data: &ParenthesizedParameterData,
) -> (hir::PathParameters, bool) {
const DISALLOWED: ImplTraitContext = ImplTraitContext::Disallowed;
let &ParenthesizedParameterData { ref inputs, ref output, span } = data;
let inputs = inputs.iter().map(|ty| self.lower_ty(ty, DISALLOWED)).collect();
let &ParenthesizedParameterData {
ref inputs,
ref output,
span,
} = data;
let inputs = inputs
.iter()
.map(|ty| self.lower_ty(ty, DISALLOWED))
.collect();
let mk_tup = |this: &mut Self, tys, span| {
let LoweredNodeId { node_id, hir_id } = this.next_id();
P(hir::Ty { node: hir::TyTup(tys), id: node_id, hir_id, span })
P(hir::Ty {
node: hir::TyTup(tys),
id: node_id,
hir_id,
span,
})
};
(hir::PathParameters {
lifetimes: hir::HirVec::new(),
types: hir_vec![mk_tup(self, inputs, span)],
bindings: hir_vec![hir::TypeBinding {
id: self.next_id().node_id,
name: Symbol::intern(FN_OUTPUT_NAME),
ty: output.as_ref().map(|ty| self.lower_ty(&ty, DISALLOWED))
.unwrap_or_else(|| mk_tup(self, hir::HirVec::new(), span)),
span: output.as_ref().map_or(span, |ty| ty.span),
}],
parenthesized: true,
}, false)
(
hir::PathParameters {
lifetimes: hir::HirVec::new(),
types: hir_vec![mk_tup(self, inputs, span)],
bindings: hir_vec![
hir::TypeBinding {
id: self.next_id().node_id,
name: Symbol::intern(FN_OUTPUT_NAME),
ty: output
.as_ref()
.map(|ty| self.lower_ty(&ty, DISALLOWED))
.unwrap_or_else(|| mk_tup(self, hir::HirVec::new(), span)),
span: output.as_ref().map_or(span, |ty| ty.span),
}
],
parenthesized: true,
},
false,
)
}
fn lower_local(&mut self, l: &Local) -> P<hir::Local> {
@@ -1468,7 +1711,9 @@ fn lower_local(&mut self, l: &Local) -> P<hir::Local> {
P(hir::Local {
id: node_id,
hir_id,
ty: l.ty.as_ref().map(|t| self.lower_ty(t, ImplTraitContext::Disallowed)),
ty: l.ty
.as_ref()
.map(|t| self.lower_ty(t, ImplTraitContext::Disallowed)),
pat: self.lower_pat(&l.pat),
init: l.init.as_ref().map(|e| P(self.lower_expr(e))),
span: l.span,
@@ -1493,24 +1738,22 @@ fn lower_arg(&mut self, arg: &Arg) -> hir::Arg {
}
}
fn lower_fn_args_to_names(&mut self, decl: &FnDecl)
-> hir::HirVec<Spanned<Name>> {
decl.inputs.iter().map(|arg| {
match arg.pat.node {
PatKind::Ident(_, ident, None) => {
respan(ident.span, ident.node.name)
}
fn lower_fn_args_to_names(&mut self, decl: &FnDecl) -> hir::HirVec<Spanned<Name>> {
decl.inputs
.iter()
.map(|arg| match arg.pat.node {
PatKind::Ident(_, ident, None) => respan(ident.span, ident.node.name),
_ => respan(arg.pat.span, keywords::Invalid.name()),
}
}).collect()
})
.collect()
}
fn lower_fn_decl(&mut self,
decl: &FnDecl,
fn_def_id: Option<DefId>,
impl_trait_return_allow: bool)
-> P<hir::FnDecl> {
fn lower_fn_decl(
&mut self,
decl: &FnDecl,
fn_def_id: Option<DefId>,
impl_trait_return_allow: bool,
) -> P<hir::FnDecl> {
// NOTE: The two last parameters here have to do with impl Trait. If fn_def_id is Some,
// then impl Trait arguments are lowered into generic parameters on the given
// fn_def_id, otherwise impl Trait is disallowed. (for now)
@@ -1519,38 +1762,44 @@ fn lower_fn_decl(&mut self,
// return positions as well. This guards against trait declarations and their impls
// where impl Trait is disallowed. (again for now)
P(hir::FnDecl {
inputs: decl.inputs.iter()
.map(|arg| if let Some(def_id) = fn_def_id {
self.lower_ty(&arg.ty, ImplTraitContext::Universal(def_id))
} else {
self.lower_ty(&arg.ty, ImplTraitContext::Disallowed)
}).collect(),
inputs: decl.inputs
.iter()
.map(|arg| {
if let Some(def_id) = fn_def_id {
self.lower_ty(&arg.ty, ImplTraitContext::Universal(def_id))
} else {
self.lower_ty(&arg.ty, ImplTraitContext::Disallowed)
}
})
.collect(),
output: match decl.output {
FunctionRetTy::Ty(ref ty) => match fn_def_id {
Some(_) if impl_trait_return_allow =>
hir::Return(self.lower_ty(ty, ImplTraitContext::Existential)),
Some(_) if impl_trait_return_allow => {
hir::Return(self.lower_ty(ty, ImplTraitContext::Existential))
}
_ => hir::Return(self.lower_ty(ty, ImplTraitContext::Disallowed)),
},
FunctionRetTy::Default(span) => hir::DefaultReturn(span),
},
variadic: decl.variadic,
has_implicit_self: decl.inputs.get(0).map_or(false, |arg| {
match arg.ty.node {
TyKind::ImplicitSelf => true,
TyKind::Rptr(_, ref mt) => mt.ty.node == TyKind::ImplicitSelf,
_ => false
}
})
has_implicit_self: decl.inputs.get(0).map_or(false, |arg| match arg.ty.node {
TyKind::ImplicitSelf => true,
TyKind::Rptr(_, ref mt) => mt.ty.node == TyKind::ImplicitSelf,
_ => false,
}),
})
}
fn lower_ty_param_bound(&mut self, tpb: &TyParamBound, itctx: ImplTraitContext)
-> hir::TyParamBound {
fn lower_ty_param_bound(
&mut self,
tpb: &TyParamBound,
itctx: ImplTraitContext,
) -> hir::TyParamBound {
match *tpb {
TraitTyParamBound(ref ty, modifier) => {
hir::TraitTyParamBound(self.lower_poly_trait_ref(ty, itctx),
self.lower_trait_bound_modifier(modifier))
}
TraitTyParamBound(ref ty, modifier) => hir::TraitTyParamBound(
self.lower_poly_trait_ref(ty, itctx),
self.lower_trait_bound_modifier(modifier),
),
RegionTyParamBound(ref lifetime) => {
hir::RegionTyParamBound(self.lower_lifetime(lifetime))
}
@@ -1570,48 +1819,60 @@ fn lower_ty_param(&mut self, tp: &TyParam, add_bounds: &[TyParamBound]) -> hir::
let itctx = ImplTraitContext::Universal(self.resolver.definitions().local_def_id(tp.id));
let mut bounds = self.lower_bounds(&tp.bounds, itctx);
if !add_bounds.is_empty() {
bounds = bounds.into_iter().chain(
self.lower_bounds(add_bounds, itctx).into_iter()
).collect();
bounds = bounds
.into_iter()
.chain(self.lower_bounds(add_bounds, itctx).into_iter())
.collect();
}
hir::TyParam {
id: self.lower_node_id(tp.id).node_id,
name,
bounds,
default: tp.default.as_ref().map(|x| self.lower_ty(x, ImplTraitContext::Disallowed)),
default: tp.default
.as_ref()
.map(|x| self.lower_ty(x, ImplTraitContext::Disallowed)),
span: tp.span,
pure_wrt_drop: attr::contains_name(&tp.attrs, "may_dangle"),
synthetic: tp.attrs.iter()
.filter(|attr| attr.check_name("rustc_synthetic"))
.map(|_| hir::SyntheticTyParamKind::ImplTrait)
.nth(0),
synthetic: tp.attrs
.iter()
.filter(|attr| attr.check_name("rustc_synthetic"))
.map(|_| hir::SyntheticTyParamKind::ImplTrait)
.nth(0),
attrs: self.lower_attrs(&tp.attrs),
}
}
fn lower_lifetime(&mut self, l: &Lifetime) -> hir::Lifetime {
let name = match self.lower_ident(l.ident) {
x if x == "'_" => hir::LifetimeName::Underscore,
x if x == "'static" => hir::LifetimeName::Static,
name => {
if self.is_collecting_in_band_lifetimes &&
!self.in_scope_lifetimes.contains(&name) &&
self.lifetimes_to_define.iter()
.find(|&&(_, lt_name)| lt_name == name)
.is_none()
{
self.lifetimes_to_define.push((l.span, name));
match self.lower_ident(l.ident) {
x if x == "'static" => self.new_named_lifetime(l.id, l.span, hir::LifetimeName::Static),
x if x == "'_" => match self.anonymous_lifetime_mode {
AnonymousLifetimeMode::CreateParameter => {
let fresh_name = self.collect_fresh_in_band_lifetime(l.span);
self.new_named_lifetime(l.id, l.span, fresh_name)
}
hir::LifetimeName::Name(name)
AnonymousLifetimeMode::PassThrough => {
self.new_named_lifetime(l.id, l.span, hir::LifetimeName::Underscore)
}
},
name => {
self.maybe_collect_in_band_lifetime(l.span, name);
self.new_named_lifetime(l.id, l.span, hir::LifetimeName::Name(name))
}
};
}
}
fn new_named_lifetime(
&mut self,
id: NodeId,
span: Span,
name: hir::LifetimeName,
) -> hir::Lifetime {
hir::Lifetime {
id: self.lower_node_id(l.id).node_id,
name,
span: l.span,
id: self.lower_node_id(id).node_id,
span,
name: name,
}
}
@@ -1640,17 +1901,16 @@ fn lower_generic_params(
params: &Vec<GenericParam>,
add_bounds: &NodeMap<Vec<TyParamBound>>,
) -> hir::HirVec<hir::GenericParam> {
params.iter()
params
.iter()
.map(|param| match *param {
GenericParam::Lifetime(ref lifetime_def) => {
hir::GenericParam::Lifetime(self.lower_lifetime_def(lifetime_def))
}
GenericParam::Type(ref ty_param) => {
hir::GenericParam::Type(self.lower_ty_param(
ty_param,
add_bounds.get(&ty_param.id).map_or(&[][..], |x| &x)
))
}
GenericParam::Type(ref ty_param) => hir::GenericParam::Type(self.lower_ty_param(
ty_param,
add_bounds.get(&ty_param.id).map_or(&[][..], |x| &x),
)),
})
.collect()
}
@@ -1666,24 +1926,30 @@ fn lower_generics(&mut self, g: &Generics) -> hir::Generics {
'next_bound: for bound in &bound_pred.bounds {
if let TraitTyParamBound(_, TraitBoundModifier::Maybe) = *bound {
let report_error = |this: &mut Self| {
this.diagnostic().span_err(bound_pred.bounded_ty.span,
"`?Trait` bounds are only permitted at the \
point where a type parameter is declared");
this.diagnostic().span_err(
bound_pred.bounded_ty.span,
"`?Trait` bounds are only permitted at the \
point where a type parameter is declared",
);
};
// Check if the where clause type is a plain type parameter.
match bound_pred.bounded_ty.node {
TyKind::Path(None, ref path)
if path.segments.len() == 1 &&
bound_pred.bound_generic_params.is_empty() => {
if let Some(Def::TyParam(def_id)) =
self.resolver.get_resolution(bound_pred.bounded_ty.id)
.map(|d| d.base_def()) {
if path.segments.len() == 1
&& bound_pred.bound_generic_params.is_empty() =>
{
if let Some(Def::TyParam(def_id)) = self.resolver
.get_resolution(bound_pred.bounded_ty.id)
.map(|d| d.base_def())
{
if let Some(node_id) =
self.resolver.definitions().as_local_node_id(def_id) {
self.resolver.definitions().as_local_node_id(def_id)
{
for param in &g.params {
if let GenericParam::Type(ref ty_param) = *param {
if node_id == ty_param.id {
add_bounds.entry(ty_param.id)
add_bounds
.entry(ty_param.id)
.or_insert(Vec::new())
.push(bound.clone());
continue 'next_bound;
@@ -1694,7 +1960,7 @@ fn lower_generics(&mut self, g: &Generics) -> hir::Generics {
}
report_error(self)
}
_ => report_error(self)
_ => report_error(self),
}
}
}
@@ -1712,81 +1978,93 @@ fn lower_where_clause(&mut self, wc: &WhereClause) -> hir::WhereClause {
hir::WhereClause {
id: self.lower_node_id(wc.id).node_id,
predicates: wc.predicates
.iter()
.map(|predicate| self.lower_where_predicate(predicate))
.collect(),
.iter()
.map(|predicate| self.lower_where_predicate(predicate))
.collect(),
}
}
fn lower_where_predicate(&mut self, pred: &WherePredicate) -> hir::WherePredicate {
match *pred {
WherePredicate::BoundPredicate(WhereBoundPredicate{ ref bound_generic_params,
ref bounded_ty,
ref bounds,
span}) => {
WherePredicate::BoundPredicate(WhereBoundPredicate {
ref bound_generic_params,
ref bounded_ty,
ref bounds,
span,
}) => {
self.with_in_scope_lifetime_defs(
&bound_generic_params.iter()
.filter_map(|p| match *p {
GenericParam::Lifetime(ref ld) => Some(ld.clone()),
_ => None,
})
.collect::<Vec<_>>(),
bound_generic_params.iter().filter_map(|p| match p {
GenericParam::Lifetime(ld) => Some(ld),
_ => None,
}),
|this| {
hir::WherePredicate::BoundPredicate(hir::WhereBoundPredicate {
bound_generic_params:
this.lower_generic_params(bound_generic_params, &NodeMap()),
bound_generic_params: this.lower_generic_params(
bound_generic_params,
&NodeMap(),
),
bounded_ty: this.lower_ty(bounded_ty, ImplTraitContext::Disallowed),
bounds: bounds.iter().filter_map(|bound| match *bound {
// Ignore `?Trait` bounds.
// Tthey were copied into type parameters already.
TraitTyParamBound(_, TraitBoundModifier::Maybe) => None,
_ => Some(this.lower_ty_param_bound(
bound, ImplTraitContext::Disallowed))
}).collect(),
bounds: bounds
.iter()
.filter_map(|bound| match *bound {
// Ignore `?Trait` bounds.
// Tthey were copied into type parameters already.
TraitTyParamBound(_, TraitBoundModifier::Maybe) => None,
_ => Some(this.lower_ty_param_bound(
bound,
ImplTraitContext::Disallowed,
)),
})
.collect(),
span,
})
}
},
)
}
WherePredicate::RegionPredicate(WhereRegionPredicate{ ref lifetime,
ref bounds,
span}) => {
hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate {
span,
lifetime: self.lower_lifetime(lifetime),
bounds: bounds.iter().map(|bound| self.lower_lifetime(bound)).collect(),
})
}
WherePredicate::EqPredicate(WhereEqPredicate{ id,
ref lhs_ty,
ref rhs_ty,
span}) => {
hir::WherePredicate::EqPredicate(hir::WhereEqPredicate {
id: self.lower_node_id(id).node_id,
lhs_ty: self.lower_ty(lhs_ty, ImplTraitContext::Disallowed),
rhs_ty: self.lower_ty(rhs_ty, ImplTraitContext::Disallowed),
span,
})
}
WherePredicate::RegionPredicate(WhereRegionPredicate {
ref lifetime,
ref bounds,
span,
}) => hir::WherePredicate::RegionPredicate(hir::WhereRegionPredicate {
span,
lifetime: self.lower_lifetime(lifetime),
bounds: bounds
.iter()
.map(|bound| self.lower_lifetime(bound))
.collect(),
}),
WherePredicate::EqPredicate(WhereEqPredicate {
id,
ref lhs_ty,
ref rhs_ty,
span,
}) => hir::WherePredicate::EqPredicate(hir::WhereEqPredicate {
id: self.lower_node_id(id).node_id,
lhs_ty: self.lower_ty(lhs_ty, ImplTraitContext::Disallowed),
rhs_ty: self.lower_ty(rhs_ty, ImplTraitContext::Disallowed),
span,
}),
}
}
fn lower_variant_data(&mut self, vdata: &VariantData) -> hir::VariantData {
match *vdata {
VariantData::Struct(ref fields, id) => {
hir::VariantData::Struct(fields.iter()
.enumerate()
.map(|f| self.lower_struct_field(f))
.collect(),
self.lower_node_id(id).node_id)
}
VariantData::Tuple(ref fields, id) => {
hir::VariantData::Tuple(fields.iter()
.enumerate()
.map(|f| self.lower_struct_field(f))
.collect(),
self.lower_node_id(id).node_id)
}
VariantData::Struct(ref fields, id) => hir::VariantData::Struct(
fields
.iter()
.enumerate()
.map(|f| self.lower_struct_field(f))
.collect(),
self.lower_node_id(id).node_id,
),
VariantData::Tuple(ref fields, id) => hir::VariantData::Tuple(
fields
.iter()
.enumerate()
.map(|f| self.lower_struct_field(f))
.collect(),
self.lower_node_id(id).node_id,
),
VariantData::Unit(id) => hir::VariantData::Unit(self.lower_node_id(id).node_id),
}
}
@@ -1794,7 +2072,7 @@ fn lower_variant_data(&mut self, vdata: &VariantData) -> hir::VariantData {
fn lower_trait_ref(&mut self, p: &TraitRef, itctx: ImplTraitContext) -> hir::TraitRef {
let path = match self.lower_qpath(p.ref_id, &None, &p.path, ParamMode::Explicit, itctx) {
hir::QPath::Resolved(None, path) => path.and_then(|path| path),
qpath => bug!("lower_trait_ref: unexpected QPath `{:?}`", qpath)
qpath => bug!("lower_trait_ref: unexpected QPath `{:?}`", qpath),
};
hir::TraitRef {
path,
@@ -1802,13 +2080,15 @@ fn lower_trait_ref(&mut self, p: &TraitRef, itctx: ImplTraitContext) -> hir::Tra
}
}
fn lower_poly_trait_ref(&mut self,
p: &PolyTraitRef,
itctx: ImplTraitContext)
-> hir::PolyTraitRef {
fn lower_poly_trait_ref(
&mut self,
p: &PolyTraitRef,
itctx: ImplTraitContext,
) -> hir::PolyTraitRef {
let bound_generic_params = self.lower_generic_params(&p.bound_generic_params, &NodeMap());
let trait_ref = self.with_parent_impl_lifetime_defs(
&bound_generic_params.iter()
&bound_generic_params
.iter()
.filter_map(|p| match *p {
hir::GenericParam::Lifetime(ref ld) => Some(ld.clone()),
_ => None,
@@ -1831,7 +2111,10 @@ fn lower_struct_field(&mut self, (index, f): (usize, &StructField)) -> hir::Stru
name: self.lower_ident(match f.ident {
Some(ident) => ident,
// FIXME(jseyfried) positional field hygiene
None => Ident { name: Symbol::intern(&index.to_string()), ctxt: f.span.ctxt() },
None => Ident {
name: Symbol::intern(&index.to_string()),
ctxt: f.span.ctxt(),
},
}),
vis: self.lower_visibility(&f.vis, None),
ty: self.lower_ty(&f.ty, ImplTraitContext::Disallowed),
@@ -1855,9 +2138,15 @@ fn lower_mt(&mut self, mt: &MutTy, itctx: ImplTraitContext) -> hir::MutTy {
}
}
fn lower_bounds(&mut self, bounds: &[TyParamBound], itctx: ImplTraitContext)
-> hir::TyParamBounds {
bounds.iter().map(|bound| self.lower_ty_param_bound(bound, itctx)).collect()
fn lower_bounds(
&mut self,
bounds: &[TyParamBound],
itctx: ImplTraitContext,
) -> hir::TyParamBounds {
bounds
.iter()
.map(|bound| self.lower_ty_param_bound(bound, itctx))
.collect()
}
fn lower_block(&mut self, b: &Block, targeted_by_break: bool) -> P<hir::Block> {
@@ -1891,13 +2180,14 @@ fn lower_block(&mut self, b: &Block, targeted_by_break: bool) -> P<hir::Block> {
})
}
fn lower_item_kind(&mut self,
id: NodeId,
name: &mut Name,
attrs: &hir::HirVec<Attribute>,
vis: &mut hir::Visibility,
i: &ItemKind)
-> hir::Item_ {
fn lower_item_kind(
&mut self,
id: NodeId,
name: &mut Name,
attrs: &hir::HirVec<Attribute>,
vis: &mut hir::Visibility,
i: &ItemKind,
) -> hir::Item_ {
match *i {
ItemKind::ExternCrate(orig_name) => hir::ItemExternCrate(orig_name),
ItemKind::Use(ref use_tree) => {
@@ -1911,49 +2201,57 @@ fn lower_item_kind(&mut self,
}
ItemKind::Static(ref t, m, ref e) => {
let value = self.lower_body(None, |this| this.lower_expr(e));
hir::ItemStatic(self.lower_ty(t, ImplTraitContext::Disallowed),
self.lower_mutability(m),
value)
hir::ItemStatic(
self.lower_ty(t, ImplTraitContext::Disallowed),
self.lower_mutability(m),
value,
)
}
ItemKind::Const(ref t, ref e) => {
let value = self.lower_body(None, |this| this.lower_expr(e));
hir::ItemConst(self.lower_ty(t, ImplTraitContext::Disallowed), value)
}
ItemKind::Fn(ref decl, unsafety, constness, abi, ref generics, ref body) => {
let fn_def_id = self.resolver.definitions().opt_local_def_id(id);
let fn_def_id = self.resolver.definitions().local_def_id(id);
self.with_new_scopes(|this| {
let body_id = this.lower_body(Some(decl), |this| {
let body = this.lower_block(body, false);
this.expr_block(body, ThinVec::new())
});
let (generics, fn_decl) =
this.add_in_band_defs(generics, fn_def_id, |this|
this.lower_fn_decl(decl, fn_def_id, true));
let (generics, fn_decl) = this.add_in_band_defs(
generics,
fn_def_id,
AnonymousLifetimeMode::PassThrough,
|this| this.lower_fn_decl(decl, Some(fn_def_id), true),
);
hir::ItemFn(fn_decl,
this.lower_unsafety(unsafety),
this.lower_constness(constness),
abi,
generics,
body_id)
hir::ItemFn(
fn_decl,
this.lower_unsafety(unsafety),
this.lower_constness(constness),
abi,
generics,
body_id,
)
})
}
ItemKind::Mod(ref m) => hir::ItemMod(self.lower_mod(m)),
ItemKind::ForeignMod(ref nm) => hir::ItemForeignMod(self.lower_foreign_mod(nm)),
ItemKind::GlobalAsm(ref ga) => hir::ItemGlobalAsm(self.lower_global_asm(ga)),
ItemKind::Ty(ref t, ref generics) => {
hir::ItemTy(self.lower_ty(t, ImplTraitContext::Disallowed),
self.lower_generics(generics))
}
ItemKind::Enum(ref enum_definition, ref generics) => {
hir::ItemEnum(hir::EnumDef {
variants: enum_definition.variants
.iter()
.map(|x| self.lower_variant(x))
.collect(),
},
self.lower_generics(generics))
}
ItemKind::Ty(ref t, ref generics) => hir::ItemTy(
self.lower_ty(t, ImplTraitContext::Disallowed),
self.lower_generics(generics),
),
ItemKind::Enum(ref enum_definition, ref generics) => hir::ItemEnum(
hir::EnumDef {
variants: enum_definition
.variants
.iter()
.map(|x| self.lower_variant(x))
.collect(),
},
self.lower_generics(generics),
),
ItemKind::Struct(ref struct_def, ref generics) => {
let struct_def = self.lower_variant_data(struct_def);
hir::ItemStruct(struct_def, self.lower_generics(generics))
@@ -1962,21 +2260,40 @@ fn lower_item_kind(&mut self,
let vdata = self.lower_variant_data(vdata);
hir::ItemUnion(vdata, self.lower_generics(generics))
}
ItemKind::Impl(unsafety,
polarity,
defaultness,
ref ast_generics,
ref ifce,
ref ty,
ref impl_items) => {
let def_id = self.resolver.definitions().opt_local_def_id(id);
let (generics, (ifce, lowered_ty)) =
self.add_in_band_defs(ast_generics, def_id, |this| {
let ifce = ifce.as_ref().map(|trait_ref| {
ItemKind::Impl(
unsafety,
polarity,
defaultness,
ref ast_generics,
ref trait_ref,
ref ty,
ref impl_items,
) => {
let def_id = self.resolver.definitions().local_def_id(id);
// Lower the "impl header" first. This ordering is important
// for in-band lifetimes! Consider `'a` here:
//
// impl Foo<'a> for u32 {
// fn method(&'a self) { .. }
// }
//
// Because we start by lowering the `Foo<'a> for u32`
// part, we will add `'a` to the list of generics on
// the impl. When we then encounter it later in the
// method, it will not be considered an in-band
// lifetime to be added, but rather a reference to a
// parent lifetime.
let (generics, (trait_ref, lowered_ty)) = self.add_in_band_defs(
ast_generics,
def_id,
AnonymousLifetimeMode::CreateParameter,
|this| {
let trait_ref = trait_ref.as_ref().map(|trait_ref| {
this.lower_trait_ref(trait_ref, ImplTraitContext::Disallowed)
});
if let Some(ref trait_ref) = ifce {
if let Some(ref trait_ref) = trait_ref {
if let Def::Trait(def_id) = trait_ref.path.def {
this.trait_impls.entry(def_id).or_insert(vec![]).push(id);
}
@@ -1984,46 +2301,51 @@ fn lower_item_kind(&mut self,
let lowered_ty = this.lower_ty(ty, ImplTraitContext::Disallowed);
(ifce, lowered_ty)
});
let new_impl_items = self.with_in_scope_lifetime_defs(
&ast_generics.params
.iter()
.filter_map(|p| match *p {
GenericParam::Lifetime(ref ld) => Some(ld.clone()),
_ => None,
})
.collect::<Vec<_>>(),
|this| {
impl_items.iter()
.map(|item| this.lower_impl_item_ref(item))
.collect()
}
(trait_ref, lowered_ty)
},
);
let new_impl_items = self.with_in_scope_lifetime_defs(
ast_generics.params.iter().filter_map(|p| match p {
GenericParam::Lifetime(ld) => Some(ld),
_ => None,
}),
|this| {
impl_items
.iter()
.map(|item| this.lower_impl_item_ref(item))
.collect()
},
);
hir::ItemImpl(self.lower_unsafety(unsafety),
self.lower_impl_polarity(polarity),
self.lower_defaultness(defaultness, true /* [1] */),
generics,
ifce,
lowered_ty,
new_impl_items)
hir::ItemImpl(
self.lower_unsafety(unsafety),
self.lower_impl_polarity(polarity),
self.lower_defaultness(defaultness, true /* [1] */),
generics,
trait_ref,
lowered_ty,
new_impl_items,
)
}
ItemKind::Trait(is_auto, unsafety, ref generics, ref bounds, ref items) => {
let bounds = self.lower_bounds(bounds, ImplTraitContext::Disallowed);
let items = items.iter().map(|item| self.lower_trait_item_ref(item)).collect();
hir::ItemTrait(self.lower_is_auto(is_auto),
self.lower_unsafety(unsafety),
self.lower_generics(generics),
bounds,
items)
}
ItemKind::TraitAlias(ref generics, ref bounds) => {
hir::ItemTraitAlias(self.lower_generics(generics),
self.lower_bounds(bounds, ImplTraitContext::Disallowed))
let items = items
.iter()
.map(|item| self.lower_trait_item_ref(item))
.collect();
hir::ItemTrait(
self.lower_is_auto(is_auto),
self.lower_unsafety(unsafety),
self.lower_generics(generics),
bounds,
items,
)
}
ItemKind::TraitAlias(ref generics, ref bounds) => hir::ItemTraitAlias(
self.lower_generics(generics),
self.lower_bounds(bounds, ImplTraitContext::Disallowed),
),
ItemKind::MacroDef(..) | ItemKind::Mac(..) => panic!("Shouldn't still be around"),
}
@@ -2031,14 +2353,15 @@ fn lower_item_kind(&mut self,
// not cause an assertion failure inside the `lower_defaultness` function
}
fn lower_use_tree(&mut self,
tree: &UseTree,
prefix: &Path,
id: NodeId,
vis: &mut hir::Visibility,
name: &mut Name,
attrs: &hir::HirVec<Attribute>)
-> hir::Item_ {
fn lower_use_tree(
&mut self,
tree: &UseTree,
prefix: &Path,
id: NodeId,
vis: &mut hir::Visibility,
name: &mut Name,
attrs: &hir::HirVec<Attribute>,
) -> hir::Item_ {
let path = &tree.prefix;
match tree.kind {
@@ -2047,17 +2370,19 @@ fn lower_use_tree(&mut self,
// First apply the prefix to the path
let mut path = Path {
segments: prefix.segments
segments: prefix
.segments
.iter()
.chain(path.segments.iter())
.cloned()
.collect(),
span: path.span
span: path.span,
};
// Correctly resolve `self` imports
if path.segments.len() > 1 &&
path.segments.last().unwrap().identifier.name == keywords::SelfValue.name() {
if path.segments.len() > 1
&& path.segments.last().unwrap().identifier.name == keywords::SelfValue.name()
{
let _ = path.segments.pop();
if rename.is_none() {
*name = path.segments.last().unwrap().identifier.name;
@@ -2068,19 +2393,25 @@ fn lower_use_tree(&mut self,
hir::ItemUse(path, hir::UseKind::Single)
}
UseTreeKind::Glob => {
let path = P(self.lower_path(id, &Path {
segments: prefix.segments
.iter()
.chain(path.segments.iter())
.cloned()
.collect(),
span: path.span,
}, ParamMode::Explicit));
let path = P(self.lower_path(
id,
&Path {
segments: prefix
.segments
.iter()
.chain(path.segments.iter())
.cloned()
.collect(),
span: path.span,
},
ParamMode::Explicit,
));
hir::ItemUse(path, hir::UseKind::Glob)
}
UseTreeKind::Nested(ref trees) => {
let prefix = Path {
segments: prefix.segments
segments: prefix
.segments
.iter()
.chain(path.segments.iter())
.cloned()
@@ -2098,16 +2429,15 @@ fn lower_use_tree(&mut self,
let mut vis = vis.clone();
let mut name = name.clone();
let item = self.lower_use_tree(
use_tree, &prefix, new_id, &mut vis, &mut name, &attrs,
);
let item =
self.lower_use_tree(use_tree, &prefix, new_id, &mut vis, &mut name, &attrs);
self.with_hir_id_owner(new_id, |this| {
let vis = match vis {
hir::Visibility::Public => hir::Visibility::Public,
hir::Visibility::Crate => hir::Visibility::Crate,
hir::Visibility::Inherited => hir::Visibility::Inherited,
hir::Visibility::Restricted { ref path, id: _ } => {
hir::Visibility::Restricted { ref path, id: _ } => {
hir::Visibility::Restricted {
path: path.clone(),
// We are allocating a new NodeId here
@@ -2116,15 +2446,18 @@ fn lower_use_tree(&mut self,
}
};
this.items.insert(new_id, hir::Item {
id: new_id,
hir_id: new_hir_id,
name: name,
attrs: attrs.clone(),
node: item,
vis,
span: use_tree.span,
});
this.items.insert(
new_id,
hir::Item {
id: new_id,
hir_id: new_hir_id,
name: name,
attrs: attrs.clone(),
node: item,
vis,
span: use_tree.span,
},
);
});
}
@@ -2141,25 +2474,31 @@ fn lower_use_tree(&mut self,
fn lower_trait_item(&mut self, i: &TraitItem) -> hir::TraitItem {
self.with_parent_def(i.id, |this| {
let LoweredNodeId { node_id, hir_id } = this.lower_node_id(i.id);
let fn_def_id = this.resolver.definitions().opt_local_def_id(node_id);
let trait_item_def_id = this.resolver.definitions().local_def_id(node_id);
let (generics, node) = match i.node {
TraitItemKind::Const(ref ty, ref default) => {
(
this.lower_generics(&i.generics),
hir::TraitItemKind::Const(
this.lower_ty(ty, ImplTraitContext::Disallowed),
default.as_ref().map(|x| {
this.lower_body(None, |this| this.lower_expr(x))
}))
)
}
TraitItemKind::Const(ref ty, ref default) => (
this.lower_generics(&i.generics),
hir::TraitItemKind::Const(
this.lower_ty(ty, ImplTraitContext::Disallowed),
default
.as_ref()
.map(|x| this.lower_body(None, |this| this.lower_expr(x))),
),
),
TraitItemKind::Method(ref sig, None) => {
let names = this.lower_fn_args_to_names(&sig.decl);
this.add_in_band_defs(&i.generics, fn_def_id, |this|
hir::TraitItemKind::Method(
this.lower_method_sig(sig, fn_def_id, false),
hir::TraitMethod::Required(names)))
this.add_in_band_defs(
&i.generics,
trait_item_def_id,
AnonymousLifetimeMode::PassThrough,
|this| {
hir::TraitItemKind::Method(
this.lower_method_sig(sig, trait_item_def_id, false),
hir::TraitMethod::Required(names),
)
},
)
}
TraitItemKind::Method(ref sig, Some(ref body)) => {
let body_id = this.lower_body(Some(&sig.decl), |this| {
@@ -2167,21 +2506,27 @@ fn lower_trait_item(&mut self, i: &TraitItem) -> hir::TraitItem {
this.expr_block(body, ThinVec::new())
});
this.add_in_band_defs(&i.generics, fn_def_id, |this|
hir::TraitItemKind::Method(
this.lower_method_sig(sig, fn_def_id, false),
hir::TraitMethod::Provided(body_id)))
}
TraitItemKind::Type(ref bounds, ref default) => {
(
this.lower_generics(&i.generics),
hir::TraitItemKind::Type(
this.lower_bounds(bounds, ImplTraitContext::Disallowed),
default.as_ref().map(|x| {
this.lower_ty(x, ImplTraitContext::Disallowed)
}))
this.add_in_band_defs(
&i.generics,
trait_item_def_id,
AnonymousLifetimeMode::PassThrough,
|this| {
hir::TraitItemKind::Method(
this.lower_method_sig(sig, trait_item_def_id, false),
hir::TraitMethod::Provided(body_id),
)
},
)
}
TraitItemKind::Type(ref bounds, ref default) => (
this.lower_generics(&i.generics),
hir::TraitItemKind::Type(
this.lower_bounds(bounds, ImplTraitContext::Disallowed),
default
.as_ref()
.map(|x| this.lower_ty(x, ImplTraitContext::Disallowed)),
),
),
TraitItemKind::Macro(..) => panic!("Shouldn't exist any more"),
};
@@ -2205,11 +2550,12 @@ fn lower_trait_item_ref(&mut self, i: &TraitItem) -> hir::TraitItemRef {
TraitItemKind::Type(_, ref default) => {
(hir::AssociatedItemKind::Type, default.is_some())
}
TraitItemKind::Method(ref sig, ref default) => {
(hir::AssociatedItemKind::Method {
TraitItemKind::Method(ref sig, ref default) => (
hir::AssociatedItemKind::Method {
has_self: sig.decl.has_self(),
}, default.is_some())
}
},
default.is_some(),
),
TraitItemKind::Macro(..) => unimplemented!(),
};
hir::TraitItemRef {
@@ -2224,7 +2570,7 @@ fn lower_trait_item_ref(&mut self, i: &TraitItem) -> hir::TraitItemRef {
fn lower_impl_item(&mut self, i: &ImplItem) -> hir::ImplItem {
self.with_parent_def(i.id, |this| {
let LoweredNodeId { node_id, hir_id } = this.lower_node_id(i.id);
let fn_def_id = this.resolver.definitions().opt_local_def_id(node_id);
let impl_item_def_id = this.resolver.definitions().local_def_id(node_id);
let (generics, node) = match i.node {
ImplItemKind::Const(ref ty, ref expr) => {
@@ -2233,8 +2579,8 @@ fn lower_impl_item(&mut self, i: &ImplItem) -> hir::ImplItem {
this.lower_generics(&i.generics),
hir::ImplItemKind::Const(
this.lower_ty(ty, ImplTraitContext::Disallowed),
body_id
)
body_id,
),
)
}
ImplItemKind::Method(ref sig, ref body) => {
@@ -2244,15 +2590,25 @@ fn lower_impl_item(&mut self, i: &ImplItem) -> hir::ImplItem {
});
let impl_trait_return_allow = !this.is_in_trait_impl;
this.add_in_band_defs(&i.generics, fn_def_id, |this|
hir::ImplItemKind::Method(
this.lower_method_sig(sig, fn_def_id, impl_trait_return_allow),
body_id))
this.add_in_band_defs(
&i.generics,
impl_item_def_id,
AnonymousLifetimeMode::PassThrough,
|this| {
hir::ImplItemKind::Method(
this.lower_method_sig(
sig,
impl_item_def_id,
impl_trait_return_allow,
),
body_id,
)
},
)
}
ImplItemKind::Type(ref ty) => (
this.lower_generics(&i.generics),
hir::ImplItemKind::Type(
this.lower_ty(ty, ImplTraitContext::Disallowed)),
hir::ImplItemKind::Type(this.lower_ty(ty, ImplTraitContext::Disallowed)),
),
ImplItemKind::Macro(..) => panic!("Shouldn't exist any more"),
};
@@ -2283,10 +2639,8 @@ fn lower_impl_item_ref(&mut self, i: &ImplItem) -> hir::ImplItemRef {
kind: match i.node {
ImplItemKind::Const(..) => hir::AssociatedItemKind::Const,
ImplItemKind::Type(..) => hir::AssociatedItemKind::Type,
ImplItemKind::Method(ref sig, _) => {
hir::AssociatedItemKind::Method {
has_self: sig.decl.has_self(),
}
ImplItemKind::Method(ref sig, _) => hir::AssociatedItemKind::Method {
has_self: sig.decl.has_self(),
},
ImplItemKind::Macro(..) => unimplemented!(),
},
@@ -2317,12 +2671,10 @@ fn lower_item_id(&mut self, i: &Item) -> SmallVector<hir::ItemId> {
fn lower_item_id_use_tree(&self, tree: &UseTree, vec: &mut SmallVector<hir::ItemId>) {
match tree.kind {
UseTreeKind::Nested(ref nested_vec) => {
for &(ref nested, id) in nested_vec {
vec.push(hir::ItemId { id, });
self.lower_item_id_use_tree(nested, vec);
}
}
UseTreeKind::Nested(ref nested_vec) => for &(ref nested, id) in nested_vec {
vec.push(hir::ItemId { id });
self.lower_item_id_use_tree(nested, vec);
},
UseTreeKind::Glob => {}
UseTreeKind::Simple(..) => {}
}
@@ -2375,25 +2727,25 @@ fn lower_foreign_item(&mut self, i: &ForeignItem) -> hir::ForeignItem {
attrs: this.lower_attrs(&i.attrs),
node: match i.node {
ForeignItemKind::Fn(ref fdec, ref generics) => {
// Disallow impl Trait in foreign items
let (generics, (fn_dec, fn_args)) =
this.add_in_band_defs(
generics,
Some(def_id),
|this| (
let (generics, (fn_dec, fn_args)) = this.add_in_band_defs(
generics,
def_id,
AnonymousLifetimeMode::PassThrough,
|this| {
(
// Disallow impl Trait in foreign items
this.lower_fn_decl(fdec, None, false),
this.lower_fn_args_to_names(fdec)
this.lower_fn_args_to_names(fdec),
)
);
},
);
hir::ForeignItemFn(fn_dec, fn_args, generics)
}
ForeignItemKind::Static(ref t, m) => {
hir::ForeignItemStatic(this.lower_ty(t, ImplTraitContext::Disallowed), m)
}
ForeignItemKind::Ty => {
hir::ForeignItemType
}
ForeignItemKind::Ty => hir::ForeignItemType,
},
vis: this.lower_visibility(&i.vis, None),
span: i.span,
@@ -2401,16 +2753,17 @@ fn lower_foreign_item(&mut self, i: &ForeignItem) -> hir::ForeignItem {
})
}
fn lower_method_sig(&mut self,
sig: &MethodSig,
fn_def_id: Option<DefId>,
impl_trait_return_allow: bool)
-> hir::MethodSig {
fn lower_method_sig(
&mut self,
sig: &MethodSig,
fn_def_id: DefId,
impl_trait_return_allow: bool,
) -> hir::MethodSig {
hir::MethodSig {
abi: sig.abi,
unsafety: self.lower_unsafety(sig.unsafety),
constness: self.lower_constness(sig.constness),
decl: self.lower_fn_decl(&sig.decl, fn_def_id, impl_trait_return_allow),
decl: self.lower_fn_decl(&sig.decl, Some(fn_def_id), impl_trait_return_allow),
}
}
@@ -2478,52 +2831,67 @@ fn lower_pat(&mut self, p: &Pat) -> P<hir::Pat> {
def @ None | def @ Some(Def::Local(_)) => {
let canonical_id = match def {
Some(Def::Local(id)) => id,
_ => p.id
_ => p.id,
};
hir::PatKind::Binding(self.lower_binding_mode(binding_mode),
canonical_id,
respan(pth1.span, pth1.node.name),
sub.as_ref().map(|x| self.lower_pat(x)))
hir::PatKind::Binding(
self.lower_binding_mode(binding_mode),
canonical_id,
respan(pth1.span, pth1.node.name),
sub.as_ref().map(|x| self.lower_pat(x)),
)
}
Some(def) => {
hir::PatKind::Path(hir::QPath::Resolved(None, P(hir::Path {
Some(def) => hir::PatKind::Path(hir::QPath::Resolved(
None,
P(hir::Path {
span: pth1.span,
def,
segments: hir_vec![
hir::PathSegment::from_name(pth1.node.name)
],
})))
}
segments: hir_vec![hir::PathSegment::from_name(pth1.node.name)],
}),
)),
}
}
PatKind::Lit(ref e) => hir::PatKind::Lit(P(self.lower_expr(e))),
PatKind::TupleStruct(ref path, ref pats, ddpos) => {
let qpath = self.lower_qpath(p.id, &None, path, ParamMode::Optional,
ImplTraitContext::Disallowed);
hir::PatKind::TupleStruct(qpath,
pats.iter().map(|x| self.lower_pat(x)).collect(),
ddpos)
}
PatKind::Path(ref qself, ref path) => {
hir::PatKind::Path(self.lower_qpath(p.id, qself, path, ParamMode::Optional,
ImplTraitContext::Disallowed))
let qpath = self.lower_qpath(
p.id,
&None,
path,
ParamMode::Optional,
ImplTraitContext::Disallowed,
);
hir::PatKind::TupleStruct(
qpath,
pats.iter().map(|x| self.lower_pat(x)).collect(),
ddpos,
)
}
PatKind::Path(ref qself, ref path) => hir::PatKind::Path(self.lower_qpath(
p.id,
qself,
path,
ParamMode::Optional,
ImplTraitContext::Disallowed,
)),
PatKind::Struct(ref path, ref fields, etc) => {
let qpath = self.lower_qpath(p.id, &None, path, ParamMode::Optional,
ImplTraitContext::Disallowed);
let qpath = self.lower_qpath(
p.id,
&None,
path,
ParamMode::Optional,
ImplTraitContext::Disallowed,
);
let fs = fields.iter()
.map(|f| {
Spanned {
span: f.span,
node: hir::FieldPat {
name: self.lower_ident(f.node.ident),
pat: self.lower_pat(&f.node.pat),
is_shorthand: f.node.is_shorthand,
},
}
})
.collect();
let fs = fields
.iter()
.map(|f| Spanned {
span: f.span,
node: hir::FieldPat {
name: self.lower_ident(f.node.ident),
pat: self.lower_pat(&f.node.pat),
is_shorthand: f.node.is_shorthand,
},
})
.collect();
hir::PatKind::Struct(qpath, fs, etc)
}
PatKind::Tuple(ref elts, ddpos) => {
@@ -2533,16 +2901,16 @@ fn lower_pat(&mut self, p: &Pat) -> P<hir::Pat> {
PatKind::Ref(ref inner, mutbl) => {
hir::PatKind::Ref(self.lower_pat(inner), self.lower_mutability(mutbl))
}
PatKind::Range(ref e1, ref e2, ref end) => {
hir::PatKind::Range(P(self.lower_expr(e1)),
P(self.lower_expr(e2)),
self.lower_range_end(end))
}
PatKind::Slice(ref before, ref slice, ref after) => {
hir::PatKind::Slice(before.iter().map(|x| self.lower_pat(x)).collect(),
slice.as_ref().map(|x| self.lower_pat(x)),
after.iter().map(|x| self.lower_pat(x)).collect())
}
PatKind::Range(ref e1, ref e2, ref end) => hir::PatKind::Range(
P(self.lower_expr(e1)),
P(self.lower_expr(e2)),
self.lower_range_end(end),
),
PatKind::Slice(ref before, ref slice, ref after) => hir::PatKind::Slice(
before.iter().map(|x| self.lower_pat(x)).collect(),
slice.as_ref().map(|x| self.lower_pat(x)),
after.iter().map(|x| self.lower_pat(x)).collect(),
),
PatKind::Paren(ref inner) => return self.lower_pat(inner),
PatKind::Mac(_) => panic!("Shouldn't exist here"),
};
@@ -2581,9 +2949,7 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// }
//
// But for now there are type-inference issues doing that.
ExprKind::Box(ref inner) => {
hir::ExprBox(P(self.lower_expr(inner)))
}
ExprKind::Box(ref inner) => hir::ExprBox(P(self.lower_expr(inner))),
// Desugar ExprBox: `in (PLACE) EXPR`
ExprKind::InPlace(ref placer, ref value_expr) => {
@@ -2624,9 +2990,7 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
};
// let placer = <placer_expr> ;
let (s1, placer_binding) = {
mk_stmt_let(self, placer_ident, placer_expr)
};
let (s1, placer_binding) = { mk_stmt_let(self, placer_ident, placer_expr) };
// let mut place = Placer::make_place(placer);
let (s2, place_binding) = {
@@ -2645,11 +3009,13 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// pop_unsafe!(EXPR));
let pop_unsafe_expr = {
self.signal_block_expr(hir_vec![],
value_expr,
e.span,
hir::PopUnsafeBlock(hir::CompilerGenerated),
ThinVec::new())
self.signal_block_expr(
hir_vec![],
value_expr,
e.span,
hir::PopUnsafeBlock(hir::CompilerGenerated),
ThinVec::new(),
)
};
// push_unsafe!({
@@ -2658,19 +3024,21 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// })
let expr = {
let ptr = self.expr_ident(e.span, p_ptr_ident, p_ptr_binding);
let call_move_val_init =
hir::StmtSemi(
make_call(self, &move_val_init, hir_vec![ptr, pop_unsafe_expr]),
self.next_id().node_id);
let call_move_val_init = hir::StmtSemi(
make_call(self, &move_val_init, hir_vec![ptr, pop_unsafe_expr]),
self.next_id().node_id,
);
let call_move_val_init = respan(e.span, call_move_val_init);
let place = self.expr_ident(e.span, place_ident, place_binding);
let call = make_call(self, &inplace_finalize, hir_vec![place]);
P(self.signal_block_expr(hir_vec![call_move_val_init],
call,
e.span,
hir::PushUnsafeBlock(hir::CompilerGenerated),
ThinVec::new()))
P(self.signal_block_expr(
hir_vec![call_move_val_init],
call,
e.span,
hir::PushUnsafeBlock(hir::CompilerGenerated),
ThinVec::new(),
))
};
let block = self.block_all(e.span, hir_vec![s1, s2, s3], Some(expr));
@@ -2693,9 +3061,14 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
hir::ExprCall(f, args.iter().map(|x| self.lower_expr(x)).collect())
}
ExprKind::MethodCall(ref seg, ref args) => {
let hir_seg = self.lower_path_segment(e.span, seg, ParamMode::Optional, 0,
ParenthesizedGenericArgs::Err,
ImplTraitContext::Disallowed);
let hir_seg = self.lower_path_segment(
e.span,
seg,
ParamMode::Optional,
0,
ParenthesizedGenericArgs::Err,
ImplTraitContext::Disallowed,
);
let args = args.iter().map(|x| self.lower_expr(x)).collect();
hir::ExprMethodCall(hir_seg, seg.span, args)
}
@@ -2733,10 +3106,7 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// wrap the if-let expr in a block
let span = els.span;
let els = P(self.lower_expr(els));
let LoweredNodeId {
node_id,
hir_id,
} = self.next_id();
let LoweredNodeId { node_id, hir_id } = self.next_id();
let blk = P(hir::Block {
stmts: hir_vec![],
expr: Some(els),
@@ -2758,28 +3128,28 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
hir::ExprIf(P(self.lower_expr(cond)), P(then_expr), else_opt)
}
ExprKind::While(ref cond, ref body, opt_label) => {
self.with_loop_scope(e.id, |this|
hir::ExprWhile(
this.with_loop_condition_scope(|this| P(this.lower_expr(cond))),
this.lower_block(body, false),
this.lower_label(opt_label)))
}
ExprKind::Loop(ref body, opt_label) => {
self.with_loop_scope(e.id, |this|
hir::ExprLoop(this.lower_block(body, false),
this.lower_label(opt_label),
hir::LoopSource::Loop))
}
ExprKind::While(ref cond, ref body, opt_label) => self.with_loop_scope(e.id, |this| {
hir::ExprWhile(
this.with_loop_condition_scope(|this| P(this.lower_expr(cond))),
this.lower_block(body, false),
this.lower_label(opt_label),
)
}),
ExprKind::Loop(ref body, opt_label) => self.with_loop_scope(e.id, |this| {
hir::ExprLoop(
this.lower_block(body, false),
this.lower_label(opt_label),
hir::LoopSource::Loop,
)
}),
ExprKind::Catch(ref body) => {
self.with_catch_scope(body.id, |this|
hir::ExprBlock(this.lower_block(body, true)))
}
ExprKind::Match(ref expr, ref arms) => {
hir::ExprMatch(P(self.lower_expr(expr)),
arms.iter().map(|x| self.lower_arm(x)).collect(),
hir::MatchSource::Normal)
self.with_catch_scope(body.id, |this| hir::ExprBlock(this.lower_block(body, true)))
}
ExprKind::Match(ref expr, ref arms) => hir::ExprMatch(
P(self.lower_expr(expr)),
arms.iter().map(|x| self.lower_arm(x)).collect(),
hir::MatchSource::Normal,
),
ExprKind::Closure(capture_clause, movability, ref decl, ref body, fn_decl_span) => {
self.with_new_scopes(|this| {
this.with_parent_def(e.id, |this| {
@@ -2791,8 +3161,12 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
});
let generator_option = if is_generator {
if !decl.inputs.is_empty() {
span_err!(this.sess, fn_decl_span, E0628,
"generators cannot have explicit arguments");
span_err!(
this.sess,
fn_decl_span,
E0628,
"generators cannot have explicit arguments"
);
this.sess.abort_if_errors();
}
Some(match movability {
@@ -2801,16 +3175,22 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
})
} else {
if movability == Movability::Static {
span_err!(this.sess, fn_decl_span, E0906,
"closures cannot be static");
span_err!(
this.sess,
fn_decl_span,
E0906,
"closures cannot be static"
);
}
None
};
hir::ExprClosure(this.lower_capture_clause(capture_clause),
this.lower_fn_decl(decl, None, false),
body_id,
fn_decl_span,
generator_option)
hir::ExprClosure(
this.lower_capture_clause(capture_clause),
this.lower_fn_decl(decl, None, false),
body_id,
fn_decl_span,
generator_option,
)
})
})
}
@@ -2818,18 +3198,16 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
ExprKind::Assign(ref el, ref er) => {
hir::ExprAssign(P(self.lower_expr(el)), P(self.lower_expr(er)))
}
ExprKind::AssignOp(op, ref el, ref er) => {
hir::ExprAssignOp(self.lower_binop(op),
P(self.lower_expr(el)),
P(self.lower_expr(er)))
}
ExprKind::Field(ref el, ident) => {
hir::ExprField(P(self.lower_expr(el)),
respan(ident.span, self.lower_ident(ident.node)))
}
ExprKind::TupField(ref el, ident) => {
hir::ExprTupField(P(self.lower_expr(el)), ident)
}
ExprKind::AssignOp(op, ref el, ref er) => hir::ExprAssignOp(
self.lower_binop(op),
P(self.lower_expr(el)),
P(self.lower_expr(er)),
),
ExprKind::Field(ref el, ident) => hir::ExprField(
P(self.lower_expr(el)),
respan(ident.span, self.lower_ident(ident.node)),
),
ExprKind::TupField(ref el, ident) => hir::ExprTupField(P(self.lower_expr(el)), ident),
ExprKind::Index(ref el, ref er) => {
hir::ExprIndex(P(self.lower_expr(el)), P(self.lower_expr(er)))
}
@@ -2843,25 +3221,27 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
(&Some(..), &Some(..), HalfOpen) => "Range",
(&None, &Some(..), Closed) => "RangeToInclusive",
(&Some(..), &Some(..), Closed) => "RangeInclusive",
(_, &None, Closed) =>
self.diagnostic().span_fatal(
e.span, "inclusive range with no end").raise(),
(_, &None, Closed) => self.diagnostic()
.span_fatal(e.span, "inclusive range with no end")
.raise(),
};
let fields =
e1.iter().map(|e| ("start", e)).chain(e2.iter().map(|e| ("end", e)))
let fields = e1.iter()
.map(|e| ("start", e))
.chain(e2.iter().map(|e| ("end", e)))
.map(|(s, e)| {
let expr = P(self.lower_expr(&e));
let unstable_span =
self.allow_internal_unstable(CompilerDesugaringKind::DotFill, e.span);
self.field(Symbol::intern(s), expr, unstable_span)
}).collect::<P<[hir::Field]>>();
})
.collect::<P<[hir::Field]>>();
let is_unit = fields.is_empty();
let unstable_span =
self.allow_internal_unstable(CompilerDesugaringKind::DotFill, e.span);
let struct_path =
iter::once("ops").chain(iter::once(path))
let struct_path = iter::once("ops")
.chain(iter::once(path))
.collect::<Vec<_>>();
let struct_path = self.std_path(unstable_span, &struct_path, is_unit);
let struct_path = hir::QPath::Resolved(None, P(struct_path));
@@ -2880,46 +3260,53 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
attrs: e.attrs.clone(),
};
}
ExprKind::Path(ref qself, ref path) => {
hir::ExprPath(self.lower_qpath(e.id, qself, path, ParamMode::Optional,
ImplTraitContext::Disallowed))
}
ExprKind::Path(ref qself, ref path) => hir::ExprPath(self.lower_qpath(
e.id,
qself,
path,
ParamMode::Optional,
ImplTraitContext::Disallowed,
)),
ExprKind::Break(opt_label, ref opt_expr) => {
let destination = if self.is_in_loop_condition && opt_label.is_none() {
hir::Destination {
label: None,
target_id: hir::ScopeTarget::Loop(
Err(hir::LoopIdError::UnlabeledCfInWhileCondition).into()),
Err(hir::LoopIdError::UnlabeledCfInWhileCondition).into(),
),
}
} else {
self.lower_loop_destination(opt_label.map(|label| (e.id, label)))
};
hir::ExprBreak(
destination,
opt_expr.as_ref().map(|x| P(self.lower_expr(x))))
destination,
opt_expr.as_ref().map(|x| P(self.lower_expr(x))),
)
}
ExprKind::Continue(opt_label) => {
hir::ExprAgain(if self.is_in_loop_condition && opt_label.is_none() {
hir::Destination {
label: None,
target_id: hir::ScopeTarget::Loop(
Err(hir::LoopIdError::UnlabeledCfInWhileCondition).into(),
),
}
} else {
self.lower_loop_destination(opt_label.map(|label| (e.id, label)))
})
}
ExprKind::Continue(opt_label) =>
hir::ExprAgain(
if self.is_in_loop_condition && opt_label.is_none() {
hir::Destination {
label: None,
target_id: hir::ScopeTarget::Loop(Err(
hir::LoopIdError::UnlabeledCfInWhileCondition).into()),
}
} else {
self.lower_loop_destination(opt_label.map(|label| (e.id, label)))
}),
ExprKind::Ret(ref e) => hir::ExprRet(e.as_ref().map(|x| P(self.lower_expr(x)))),
ExprKind::InlineAsm(ref asm) => {
let hir_asm = hir::InlineAsm {
inputs: asm.inputs.iter().map(|&(ref c, _)| c.clone()).collect(),
outputs: asm.outputs.iter().map(|out| {
hir::InlineAsmOutput {
outputs: asm.outputs
.iter()
.map(|out| hir::InlineAsmOutput {
constraint: out.constraint.clone(),
is_rw: out.is_rw,
is_indirect: out.is_indirect,
}
}).collect(),
})
.collect(),
asm: asm.asm.clone(),
asm_str_style: asm.asm_str_style,
clobbers: asm.clobbers.clone().into(),
@@ -2928,18 +3315,27 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
dialect: asm.dialect,
ctxt: asm.ctxt,
};
let outputs =
asm.outputs.iter().map(|out| self.lower_expr(&out.expr)).collect();
let inputs =
asm.inputs.iter().map(|&(_, ref input)| self.lower_expr(input)).collect();
let outputs = asm.outputs
.iter()
.map(|out| self.lower_expr(&out.expr))
.collect();
let inputs = asm.inputs
.iter()
.map(|&(_, ref input)| self.lower_expr(input))
.collect();
hir::ExprInlineAsm(P(hir_asm), outputs, inputs)
}
ExprKind::Struct(ref path, ref fields, ref maybe_expr) => {
hir::ExprStruct(self.lower_qpath(e.id, &None, path, ParamMode::Optional,
ImplTraitContext::Disallowed),
fields.iter().map(|x| self.lower_field(x)).collect(),
maybe_expr.as_ref().map(|x| P(self.lower_expr(x))))
}
ExprKind::Struct(ref path, ref fields, ref maybe_expr) => hir::ExprStruct(
self.lower_qpath(
e.id,
&None,
path,
ParamMode::Optional,
ImplTraitContext::Disallowed,
),
fields.iter().map(|x| self.lower_field(x)).collect(),
maybe_expr.as_ref().map(|x| P(self.lower_expr(x))),
),
ExprKind::Paren(ref ex) => {
let mut ex = self.lower_expr(ex);
// include parens in span, but only if it is a super-span.
@@ -2955,9 +3351,10 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
ExprKind::Yield(ref opt_expr) => {
self.is_generator = true;
let expr = opt_expr.as_ref().map(|x| self.lower_expr(x)).unwrap_or_else(|| {
self.expr(e.span, hir::ExprTup(hir_vec![]), ThinVec::new())
});
let expr = opt_expr
.as_ref()
.map(|x| self.lower_expr(x))
.unwrap_or_else(|| self.expr(e.span, hir::ExprTup(hir_vec![]), ThinVec::new()));
hir::ExprYield(P(expr))
}
@@ -3002,7 +3399,8 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
arms.into(),
hir::MatchSource::IfLetDesugar {
contains_else_clause,
})
},
)
}
// Desugar ExprWhileLet
@@ -3019,11 +3417,13 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// Note that the block AND the condition are evaluated in the loop scope.
// This is done to allow `break` from inside the condition of the loop.
let (body, break_expr, sub_expr) = self.with_loop_scope(e.id, |this| (
this.lower_block(body, false),
this.expr_break(e.span, ThinVec::new()),
this.with_loop_condition_scope(|this| P(this.lower_expr(sub_expr))),
));
let (body, break_expr, sub_expr) = self.with_loop_scope(e.id, |this| {
(
this.lower_block(body, false),
this.expr_break(e.span, ThinVec::new()),
this.with_loop_condition_scope(|this| P(this.lower_expr(sub_expr))),
)
});
// `<pat> => <body>`
let pat_arm = {
@@ -3040,16 +3440,19 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// `match <sub_expr> { ... }`
let arms = hir_vec![pat_arm, break_arm];
let match_expr = self.expr(sub_expr.span,
hir::ExprMatch(sub_expr,
arms,
hir::MatchSource::WhileLetDesugar),
ThinVec::new());
let match_expr = self.expr(
sub_expr.span,
hir::ExprMatch(sub_expr, arms, hir::MatchSource::WhileLetDesugar),
ThinVec::new(),
);
// `[opt_ident]: loop { ... }`
let loop_block = P(self.block_expr(P(match_expr)));
let loop_expr = hir::ExprLoop(loop_block, self.lower_label(opt_label),
hir::LoopSource::WhileLet);
let loop_expr = hir::ExprLoop(
loop_block,
self.lower_label(opt_label),
hir::LoopSource::WhileLet,
);
// add attributes to the outer returned expr node
loop_expr
}
@@ -3083,9 +3486,11 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
let iter = self.str_to_ident("iter");
let next_ident = self.str_to_ident("__next");
let next_pat = self.pat_ident_binding_mode(pat.span,
next_ident,
hir::BindingAnnotation::Mutable);
let next_pat = self.pat_ident_binding_mode(
pat.span,
next_ident,
hir::BindingAnnotation::Mutable,
);
// `::std::option::Option::Some(val) => next = val`
let pat_arm = {
@@ -3093,25 +3498,26 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
let val_pat = self.pat_ident(pat.span, val_ident);
let val_expr = P(self.expr_ident(pat.span, val_ident, val_pat.id));
let next_expr = P(self.expr_ident(pat.span, next_ident, next_pat.id));
let assign = P(self.expr(pat.span,
hir::ExprAssign(next_expr, val_expr),
ThinVec::new()));
let assign = P(self.expr(
pat.span,
hir::ExprAssign(next_expr, val_expr),
ThinVec::new(),
));
let some_pat = self.pat_some(pat.span, val_pat);
self.arm(hir_vec![some_pat], assign)
};
// `::std::option::Option::None => break`
let break_arm = {
let break_expr = self.with_loop_scope(e.id, |this|
this.expr_break(e.span, ThinVec::new()));
let break_expr =
self.with_loop_scope(e.id, |this| this.expr_break(e.span, ThinVec::new()));
let pat = self.pat_none(e.span);
self.arm(hir_vec![pat], break_expr)
};
// `mut iter`
let iter_pat = self.pat_ident_binding_mode(head_sp,
iter,
hir::BindingAnnotation::Mutable);
let iter_pat =
self.pat_ident_binding_mode(head_sp, iter, hir::BindingAnnotation::Mutable);
// `match ::std::iter::Iterator::next(&mut iter) { ... }`
let match_expr = {
@@ -3119,46 +3525,48 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
let ref_mut_iter = self.expr_mut_addr_of(head_sp, iter);
let next_path = &["iter", "Iterator", "next"];
let next_path = P(self.expr_std_path(head_sp, next_path, ThinVec::new()));
let next_expr = P(self.expr_call(head_sp, next_path,
hir_vec![ref_mut_iter]));
let next_expr = P(self.expr_call(head_sp, next_path, hir_vec![ref_mut_iter]));
let arms = hir_vec![pat_arm, break_arm];
P(self.expr(head_sp,
hir::ExprMatch(next_expr, arms,
hir::MatchSource::ForLoopDesugar),
ThinVec::new()))
P(self.expr(
head_sp,
hir::ExprMatch(next_expr, arms, hir::MatchSource::ForLoopDesugar),
ThinVec::new(),
))
};
let match_stmt = respan(head_sp, hir::StmtExpr(match_expr, self.next_id().node_id));
let next_expr = P(self.expr_ident(head_sp, next_ident, next_pat.id));
// `let mut __next`
let next_let = self.stmt_let_pat(head_sp,
None,
next_pat,
hir::LocalSource::ForLoopDesugar);
let next_let =
self.stmt_let_pat(head_sp, None, next_pat, hir::LocalSource::ForLoopDesugar);
// `let <pat> = __next`
let pat = self.lower_pat(pat);
let pat_let = self.stmt_let_pat(head_sp,
let pat_let = self.stmt_let_pat(
head_sp,
Some(next_expr),
pat,
hir::LocalSource::ForLoopDesugar);
hir::LocalSource::ForLoopDesugar,
);
let body_block = self.with_loop_scope(e.id, |this| this.lower_block(body, false));
let body_expr = P(self.expr_block(body_block, ThinVec::new()));
let body_stmt = respan(body.span, hir::StmtExpr(body_expr, self.next_id().node_id));
let loop_block = P(self.block_all(e.span,
hir_vec![next_let,
match_stmt,
pat_let,
body_stmt],
None));
let loop_block = P(self.block_all(
e.span,
hir_vec![next_let, match_stmt, pat_let, body_stmt],
None,
));
// `[opt_ident]: loop { ... }`
let loop_expr = hir::ExprLoop(loop_block, self.lower_label(opt_label),
hir::LoopSource::ForLoop);
let loop_expr = hir::ExprLoop(
loop_block,
self.lower_label(opt_label),
hir::LoopSource::ForLoop,
);
let LoweredNodeId { node_id, hir_id } = self.lower_node_id(e.id);
let loop_expr = P(hir::Expr {
id: node_id,
@@ -3174,15 +3582,16 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
// `match ::std::iter::IntoIterator::into_iter(<head>) { ... }`
let into_iter_expr = {
let into_iter_path = &["iter", "IntoIterator", "into_iter"];
let into_iter = P(self.expr_std_path(head_sp, into_iter_path,
ThinVec::new()));
let into_iter = P(self.expr_std_path(head_sp, into_iter_path, ThinVec::new()));
P(self.expr_call(head_sp, into_iter, hir_vec![head]))
};
let match_expr = P(self.expr_match(head_sp,
into_iter_expr,
hir_vec![iter_arm],
hir::MatchSource::ForLoopDesugar));
let match_expr = P(self.expr_match(
head_sp,
into_iter_expr,
hir_vec![iter_arm],
hir::MatchSource::ForLoopDesugar,
));
// `{ let _result = ...; _result }`
// underscore prevents an unused_variables lint if the head diverges
@@ -3242,10 +3651,12 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
let ok_arm = {
let val_ident = self.str_to_ident("val");
let val_pat = self.pat_ident(e.span, val_ident);
let val_expr = P(self.expr_ident_with_attrs(e.span,
val_ident,
val_pat.id,
ThinVec::from(attrs.clone())));
let val_expr = P(self.expr_ident_with_attrs(
e.span,
val_ident,
val_pat.id,
ThinVec::from(attrs.clone()),
));
let ok_pat = self.pat_ok(e.span, val_pat);
self.arm(hir_vec![ok_pat], val_expr)
@@ -3265,8 +3676,7 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
};
let from_err_expr = {
let path = &["ops", "Try", "from_error"];
let from_err = P(self.expr_std_path(unstable_span, path,
ThinVec::new()));
let from_err = P(self.expr_std_path(unstable_span, path, ThinVec::new()));
P(self.expr_call(e.span, from_err, hir_vec![from_expr]))
};
@@ -3280,23 +3690,23 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
label: None,
target_id: hir::ScopeTarget::Block(catch_node),
},
Some(from_err_expr)
Some(from_err_expr),
),
thin_attrs))
thin_attrs,
))
} else {
P(self.expr(e.span,
hir::Expr_::ExprRet(Some(from_err_expr)),
thin_attrs))
P(self.expr(e.span, hir::Expr_::ExprRet(Some(from_err_expr)), thin_attrs))
};
let err_pat = self.pat_err(e.span, err_local);
self.arm(hir_vec![err_pat], ret_expr)
};
hir::ExprMatch(discr,
hir_vec![err_arm, ok_arm],
hir::MatchSource::TryDesugar)
hir::ExprMatch(
discr,
hir_vec![err_arm, ok_arm],
hir::MatchSource::TryDesugar,
)
}
ExprKind::Mac(_) => panic!("Shouldn't exist here"),
@@ -3316,39 +3726,42 @@ fn lower_expr(&mut self, e: &Expr) -> hir::Expr {
fn lower_stmt(&mut self, s: &Stmt) -> SmallVector<hir::Stmt> {
SmallVector::one(match s.node {
StmtKind::Local(ref l) => Spanned {
node: hir::StmtDecl(P(Spanned {
node: hir::DeclLocal(self.lower_local(l)),
span: s.span,
}), self.lower_node_id(s.id).node_id),
node: hir::StmtDecl(
P(Spanned {
node: hir::DeclLocal(self.lower_local(l)),
span: s.span,
}),
self.lower_node_id(s.id).node_id,
),
span: s.span,
},
StmtKind::Item(ref it) => {
// Can only use the ID once.
let mut id = Some(s.id);
return self.lower_item_id(it).into_iter().map(|item_id| Spanned {
node: hir::StmtDecl(P(Spanned {
node: hir::DeclItem(item_id),
return self.lower_item_id(it)
.into_iter()
.map(|item_id| Spanned {
node: hir::StmtDecl(
P(Spanned {
node: hir::DeclItem(item_id),
span: s.span,
}),
id.take()
.map(|id| self.lower_node_id(id).node_id)
.unwrap_or_else(|| self.next_id().node_id),
),
span: s.span,
}), id.take()
.map(|id| self.lower_node_id(id).node_id)
.unwrap_or_else(|| self.next_id().node_id)),
span: s.span,
}).collect();
}
StmtKind::Expr(ref e) => {
Spanned {
node: hir::StmtExpr(P(self.lower_expr(e)),
self.lower_node_id(s.id).node_id),
span: s.span,
}
}
StmtKind::Semi(ref e) => {
Spanned {
node: hir::StmtSemi(P(self.lower_expr(e)),
self.lower_node_id(s.id).node_id),
span: s.span,
}
})
.collect();
}
StmtKind::Expr(ref e) => Spanned {
node: hir::StmtExpr(P(self.lower_expr(e)), self.lower_node_id(s.id).node_id),
span: s.span,
},
StmtKind::Semi(ref e) => Spanned {
node: hir::StmtSemi(P(self.lower_expr(e)), self.lower_node_id(s.id).node_id),
span: s.span,
},
StmtKind::Mac(..) => panic!("Shouldn't exist here"),
})
}
@@ -3365,30 +3778,31 @@ fn lower_capture_clause(&mut self, c: CaptureBy) -> hir::CaptureClause {
/// lowered. This can happen during `lower_impl_item_ref()` where we need to
/// lower a `Visibility` value although we haven't lowered the owning
/// `ImplItem` in question yet.
fn lower_visibility(&mut self,
v: &Visibility,
explicit_owner: Option<NodeId>)
-> hir::Visibility {
fn lower_visibility(
&mut self,
v: &Visibility,
explicit_owner: Option<NodeId>,
) -> hir::Visibility {
match v.node {
VisibilityKind::Public => hir::Public,
VisibilityKind::Crate(..) => hir::Visibility::Crate,
VisibilityKind::Restricted { ref path, id, .. } => {
hir::Visibility::Restricted {
path: P(self.lower_path(id, path, ParamMode::Explicit)),
id: if let Some(owner) = explicit_owner {
self.lower_node_id_with_owner(id, owner).node_id
} else {
self.lower_node_id(id).node_id
}
}
}
VisibilityKind::Restricted { ref path, id, .. } => hir::Visibility::Restricted {
path: P(self.lower_path(id, path, ParamMode::Explicit)),
id: if let Some(owner) = explicit_owner {
self.lower_node_id_with_owner(id, owner).node_id
} else {
self.lower_node_id(id).node_id
},
},
VisibilityKind::Inherited => hir::Inherited,
}
}
fn lower_defaultness(&mut self, d: Defaultness, has_value: bool) -> hir::Defaultness {
match d {
Defaultness::Default => hir::Defaultness::Default { has_value: has_value },
Defaultness::Default => hir::Defaultness::Default {
has_value: has_value,
},
Defaultness::Final => {
assert!(has_value);
hir::Defaultness::Final
@@ -3405,8 +3819,7 @@ fn lower_block_check_mode(&mut self, b: &BlockCheckMode) -> hir::BlockCheckMode
fn lower_binding_mode(&mut self, b: &BindingMode) -> hir::BindingAnnotation {
match *b {
BindingMode::ByValue(Mutability::Immutable) =>
hir::BindingAnnotation::Unannotated,
BindingMode::ByValue(Mutability::Immutable) => hir::BindingAnnotation::Unannotated,
BindingMode::ByRef(Mutability::Immutable) => hir::BindingAnnotation::Ref,
BindingMode::ByValue(Mutability::Mutable) => hir::BindingAnnotation::Mutable,
BindingMode::ByRef(Mutability::Mutable) => hir::BindingAnnotation::RefMut,
@@ -3447,10 +3860,7 @@ fn arm(&mut self, pats: hir::HirVec<P<hir::Pat>>, expr: P<hir::Expr>) -> hir::Ar
fn field(&mut self, name: Name, expr: P<hir::Expr>, span: Span) -> hir::Field {
hir::Field {
name: Spanned {
node: name,
span,
},
name: Spanned { node: name, span },
span,
expr,
is_shorthand: false,
@@ -3462,8 +3872,12 @@ fn expr_break(&mut self, span: Span, attrs: ThinVec<Attribute>) -> P<hir::Expr>
P(self.expr(span, expr_break, attrs))
}
fn expr_call(&mut self, span: Span, e: P<hir::Expr>, args: hir::HirVec<hir::Expr>)
-> hir::Expr {
fn expr_call(
&mut self,
span: Span,
e: P<hir::Expr>,
args: hir::HirVec<hir::Expr>,
) -> hir::Expr {
self.expr(span, hir::ExprCall(e, args), ThinVec::new())
}
@@ -3471,15 +3885,21 @@ fn expr_ident(&mut self, span: Span, id: Name, binding: NodeId) -> hir::Expr {
self.expr_ident_with_attrs(span, id, binding, ThinVec::new())
}
fn expr_ident_with_attrs(&mut self, span: Span,
id: Name,
binding: NodeId,
attrs: ThinVec<Attribute>) -> hir::Expr {
let expr_path = hir::ExprPath(hir::QPath::Resolved(None, P(hir::Path {
span,
def: Def::Local(binding),
segments: hir_vec![hir::PathSegment::from_name(id)],
})));
fn expr_ident_with_attrs(
&mut self,
span: Span,
id: Name,
binding: NodeId,
attrs: ThinVec<Attribute>,
) -> hir::Expr {
let expr_path = hir::ExprPath(hir::QPath::Resolved(
None,
P(hir::Path {
span,
def: Def::Local(binding),
segments: hir_vec![hir::PathSegment::from_name(id)],
}),
));
self.expr(span, expr_path, attrs)
}
@@ -3488,21 +3908,27 @@ fn expr_mut_addr_of(&mut self, span: Span, e: P<hir::Expr>) -> hir::Expr {
self.expr(span, hir::ExprAddrOf(hir::MutMutable, e), ThinVec::new())
}
fn expr_std_path(&mut self,
span: Span,
components: &[&str],
attrs: ThinVec<Attribute>)
-> hir::Expr {
fn expr_std_path(
&mut self,
span: Span,
components: &[&str],
attrs: ThinVec<Attribute>,
) -> hir::Expr {
let path = self.std_path(span, components, true);
self.expr(span, hir::ExprPath(hir::QPath::Resolved(None, P(path))), attrs)
self.expr(
span,
hir::ExprPath(hir::QPath::Resolved(None, P(path))),
attrs,
)
}
fn expr_match(&mut self,
span: Span,
arg: P<hir::Expr>,
arms: hir::HirVec<hir::Arm>,
source: hir::MatchSource)
-> hir::Expr {
fn expr_match(
&mut self,
span: Span,
arg: P<hir::Expr>,
arms: hir::HirVec<hir::Arm>,
source: hir::MatchSource,
) -> hir::Expr {
self.expr(span, hir::ExprMatch(arg, arms, source), ThinVec::new())
}
@@ -3525,12 +3951,13 @@ fn expr(&mut self, span: Span, node: hir::Expr_, attrs: ThinVec<Attribute>) -> h
}
}
fn stmt_let_pat(&mut self,
sp: Span,
ex: Option<P<hir::Expr>>,
pat: P<hir::Pat>,
source: hir::LocalSource)
-> hir::Stmt {
fn stmt_let_pat(
&mut self,
sp: Span,
ex: Option<P<hir::Expr>>,
pat: P<hir::Pat>,
source: hir::LocalSource,
) -> hir::Stmt {
let LoweredNodeId { node_id, hir_id } = self.next_id();
let local = P(hir::Local {
@@ -3547,23 +3974,35 @@ fn stmt_let_pat(&mut self,
respan(sp, hir::StmtDecl(P(decl), self.next_id().node_id))
}
fn stmt_let(&mut self, sp: Span, mutbl: bool, ident: Name, ex: P<hir::Expr>)
-> (hir::Stmt, NodeId) {
fn stmt_let(
&mut self,
sp: Span,
mutbl: bool,
ident: Name,
ex: P<hir::Expr>,
) -> (hir::Stmt, NodeId) {
let pat = if mutbl {
self.pat_ident_binding_mode(sp, ident, hir::BindingAnnotation::Mutable)
} else {
self.pat_ident(sp, ident)
};
let pat_id = pat.id;
(self.stmt_let_pat(sp, Some(ex), pat, hir::LocalSource::Normal), pat_id)
(
self.stmt_let_pat(sp, Some(ex), pat, hir::LocalSource::Normal),
pat_id,
)
}
fn block_expr(&mut self, expr: P<hir::Expr>) -> hir::Block {
self.block_all(expr.span, hir::HirVec::new(), Some(expr))
}
fn block_all(&mut self, span: Span, stmts: hir::HirVec<hir::Stmt>, expr: Option<P<hir::Expr>>)
-> hir::Block {
fn block_all(
&mut self,
span: Span,
stmts: hir::HirVec<hir::Stmt>,
expr: Option<P<hir::Expr>>,
) -> hir::Block {
let LoweredNodeId { node_id, hir_id } = self.next_id();
hir::Block {
@@ -3594,11 +4033,12 @@ fn pat_none(&mut self, span: Span) -> P<hir::Pat> {
self.pat_std_enum(span, &["option", "Option", "None"], hir_vec![])
}
fn pat_std_enum(&mut self,
span: Span,
components: &[&str],
subpats: hir::HirVec<P<hir::Pat>>)
-> P<hir::Pat> {
fn pat_std_enum(
&mut self,
span: Span,
components: &[&str],
subpats: hir::HirVec<P<hir::Pat>>,
) -> P<hir::Pat> {
let path = self.std_path(span, components, true);
let qpath = hir::QPath::Resolved(None, P(path));
let pt = if subpats.is_empty() {
@@ -3613,20 +4053,18 @@ fn pat_ident(&mut self, span: Span, name: Name) -> P<hir::Pat> {
self.pat_ident_binding_mode(span, name, hir::BindingAnnotation::Unannotated)
}
fn pat_ident_binding_mode(&mut self, span: Span, name: Name, bm: hir::BindingAnnotation)
-> P<hir::Pat> {
fn pat_ident_binding_mode(
&mut self,
span: Span,
name: Name,
bm: hir::BindingAnnotation,
) -> P<hir::Pat> {
let LoweredNodeId { node_id, hir_id } = self.next_id();
P(hir::Pat {
id: node_id,
hir_id,
node: hir::PatKind::Binding(bm,
node_id,
Spanned {
span,
node: name,
},
None),
node: hir::PatKind::Binding(bm, node_id, Spanned { span, node: name }, None),
span,
})
}
@@ -3649,16 +4087,18 @@ fn pat(&mut self, span: Span, pat: hir::PatKind) -> P<hir::Pat> {
/// `fld.cx.use_std`, and `::core::b::c::d` otherwise.
/// The path is also resolved according to `is_value`.
fn std_path(&mut self, span: Span, components: &[&str], is_value: bool) -> hir::Path {
self.resolver.resolve_str_path(span, self.crate_root, components, is_value)
self.resolver
.resolve_str_path(span, self.crate_root, components, is_value)
}
fn signal_block_expr(&mut self,
stmts: hir::HirVec<hir::Stmt>,
expr: P<hir::Expr>,
span: Span,
rule: hir::BlockCheckMode,
attrs: ThinVec<Attribute>)
-> hir::Expr {
fn signal_block_expr(
&mut self,
stmts: hir::HirVec<hir::Stmt>,
expr: P<hir::Expr>,
span: Span,
rule: hir::BlockCheckMode,
attrs: ThinVec<Attribute>,
) -> hir::Expr {
let LoweredNodeId { node_id, hir_id } = self.next_id();
let block = P(hir::Block {
@@ -3692,17 +4132,93 @@ fn ty_path(&mut self, id: LoweredNodeId, span: Span, qpath: hir::QPath) -> P<hir
// The original ID is taken by the `PolyTraitRef`,
// so the `Ty` itself needs a different one.
id = self.next_id();
hir::TyTraitObject(hir_vec![principal], self.elided_lifetime(span))
hir::TyTraitObject(hir_vec![principal], self.elided_dyn_bound(span))
} else {
hir::TyPath(hir::QPath::Resolved(None, path))
}
}
_ => hir::TyPath(qpath)
_ => hir::TyPath(qpath),
};
P(hir::Ty { id: id.node_id, hir_id: id.hir_id, node, span })
P(hir::Ty {
id: id.node_id,
hir_id: id.hir_id,
node,
span,
})
}
fn elided_lifetime(&mut self, span: Span) -> hir::Lifetime {
/// Invoked to create the lifetime argument for a type `&T`
/// with no explicit lifetime.
fn elided_ref_lifetime(&mut self, span: Span) -> hir::Lifetime {
match self.anonymous_lifetime_mode {
// Intercept when we are in an impl header and introduce an in-band lifetime.
// Hence `impl Foo for &u32` becomes `impl<'f> Foo for &'f u32` for some fresh
// `'f`.
AnonymousLifetimeMode::CreateParameter => {
let fresh_name = self.collect_fresh_in_band_lifetime(span);
hir::Lifetime {
id: self.next_id().node_id,
span,
name: fresh_name,
}
}
AnonymousLifetimeMode::PassThrough => self.new_implicit_lifetime(span),
}
}
/// Invoked to create the lifetime argument(s) for a path like
/// `std::cell::Ref<T>`; note that implicit lifetimes in these
/// sorts of cases are deprecated. This may therefore report a warning or an
/// error, depending on the mode.
fn elided_path_lifetimes(&mut self, span: Span, count: usize) -> P<[hir::Lifetime]> {
match self.anonymous_lifetime_mode {
// NB. We intentionally ignore the create-parameter mode here
// and instead "pass through" to resolve-lifetimes, which will then
// report an error. This is because we don't want to support
// impl elision for deprecated forms like
//
// impl Foo for std::cell::Ref<u32> // note lack of '_
AnonymousLifetimeMode::CreateParameter => {}
// This is the normal case.
AnonymousLifetimeMode::PassThrough => {}
}
(0..count)
.map(|_| self.new_implicit_lifetime(span))
.collect()
}
/// Invoked to create the lifetime argument(s) for an elided trait object
/// bound, like the bound in `Box<dyn Debug>`. This method is not invoked
/// when the bound is written, even if it is written with `'_` like in
/// `Box<dyn Debug + '_>`. In those cases, `lower_lifetime` is invoked.
fn elided_dyn_bound(&mut self, span: Span) -> hir::Lifetime {
match self.anonymous_lifetime_mode {
// NB. We intentionally ignore the create-parameter mode here.
// and instead "pass through" to resolve-lifetimes, which will apply
// the object-lifetime-defaulting rules. Elided object lifetime defaults
// do not act like other elided lifetimes. In other words, given this:
//
// impl Foo for Box<dyn Debug>
//
// we do not introduce a fresh `'_` to serve as the bound, but instead
// ultimately translate to the equivalent of:
//
// impl Foo for Box<dyn Debug + 'static>
//
// `resolve_lifetime` has the code to make that happen.
AnonymousLifetimeMode::CreateParameter => {}
// This is the normal case.
AnonymousLifetimeMode::PassThrough => {}
}
self.new_implicit_lifetime(span)
}
fn new_implicit_lifetime(&mut self, span: Span) -> hir::Lifetime {
hir::Lifetime {
id: self.next_id().node_id,
span,
@@ -3713,9 +4229,11 @@ fn elided_lifetime(&mut self, span: Span) -> hir::Lifetime {
fn maybe_lint_bare_trait(&self, span: Span, id: NodeId, is_global: bool) {
if self.sess.features_untracked().dyn_trait {
self.sess.buffer_lint_with_diagnostic(
builtin::BARE_TRAIT_OBJECT, id, span,
builtin::BARE_TRAIT_OBJECT,
id,
span,
"trait objects without an explicit `dyn` are deprecated",
builtin::BuiltinLintDiagnostics::BareTraitObject(span, is_global)
builtin::BuiltinLintDiagnostics::BareTraitObject(span, is_global),
)
}
}
src/librustc/hir/mod.rs
+30 -2
View File
@@ -203,9 +203,31 @@ pub struct Lifetime {
#[derive(Debug, Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Copy)]
pub enum LifetimeName {
/// User typed nothing. e.g. the lifetime in `&u32`.
Implicit,
/// User typed `'_`.
Underscore,
/// Synthetic name generated when user elided a lifetime in an impl header,
/// e.g. the lifetimes in cases like these:
///
/// impl Foo for &u32
/// impl Foo<'_> for u32
///
/// in that case, we rewrite to
///
/// impl<'f> Foo for &'f u32
/// impl<'f> Foo<'f> for u32
///
/// where `'f` is something like `Fresh(0)`. The indices are
/// unique per impl, but not necessarily continuous.
Fresh(usize),
/// User wrote `'static`
Static,
/// Some user-given name like `'x`
Name(Name),
}
@@ -214,7 +236,7 @@ pub fn name(&self) -> Name {
use self::LifetimeName::*;
match *self {
Implicit => keywords::Invalid.name(),
Underscore => keywords::UnderscoreLifetime.name(),
Fresh(_) | Underscore => keywords::UnderscoreLifetime.name(),
Static => keywords::StaticLifetime.name(),
Name(name) => name,
}
@@ -235,7 +257,13 @@ pub fn is_elided(&self) -> bool {
use self::LifetimeName::*;
match self.name {
Implicit | Underscore => true,
Static | Name(_) => false,
// It might seem surprising that `Fresh(_)` counts as
// *not* elided -- but this is because, as far as the code
// in the compiler is concerned -- `Fresh(_)` variants act
// equivalently to "some fresh name". They correspond to
// early-bound regions on an impl, in other words.
Fresh(_) | Static | Name(_) => false,
}
}
src/librustc/ich/impls_hir.rs
+1
View File
@@ -145,6 +145,7 @@ fn hash_stable<W: StableHasherResult>(&self,
impl_stable_hash_for!(enum hir::LifetimeName {
Implicit,
Underscore,
Fresh(index),
Static,
Name(name)
});
src/librustc/middle/resolve_lifetime.rs
+95 -70
View File
@@ -31,6 +31,7 @@
use syntax_pos::Span;
use errors::DiagnosticBuilder;
use util::nodemap::{DefIdMap, FxHashMap, FxHashSet, NodeMap, NodeSet};
use session::Session;
use std::slice;
use rustc::lint;
@@ -468,11 +469,8 @@ fn visit_nested_body(&mut self, body: hir::BodyId) {
fn visit_item(&mut self, item: &'tcx hir::Item) {
match item.node {
hir::ItemFn(ref decl, _, _, _, ref generics, _) => {
self.visit_early_late(None,
decl,
generics,
|this| {
intravisit::walk_item(this, item);
self.visit_early_late(None, decl, generics, |this| {
intravisit::walk_item(this, item);
});
}
@@ -505,7 +503,8 @@ fn visit_item(&mut self, item: &'tcx hir::Item) {
} else {
0
};
let lifetimes = generics.lifetimes()
let lifetimes = generics
.lifetimes()
.map(|def| Region::early(&self.tcx.hir, &mut index, def))
.collect();
let next_early_index = index + generics.ty_params().count() as u32;
@@ -526,12 +525,9 @@ fn visit_item(&mut self, item: &'tcx hir::Item) {
fn visit_foreign_item(&mut self, item: &'tcx hir::ForeignItem) {
match item.node {
hir::ForeignItemFn(ref decl, _, ref generics) => {
self.visit_early_late(None,
decl,
generics,
|this| {
intravisit::walk_foreign_item(this, item);
})
self.visit_early_late(None, decl, generics, |this| {
intravisit::walk_foreign_item(this, item);
})
}
hir::ForeignItemStatic(..) => {
intravisit::walk_foreign_item(self, item);
@@ -586,7 +582,7 @@ fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
// cc #48468
self.resolve_elided_lifetimes(slice::from_ref(lifetime), false)
}
LifetimeName::Static | LifetimeName::Name(_) => {
LifetimeName::Fresh(_) | LifetimeName::Static | LifetimeName::Name(_) => {
// If the user wrote an explicit name, use that.
self.visit_lifetime(lifetime);
}
@@ -670,7 +666,7 @@ fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
if let Some(elision_region) = elision {
let scope = Scope::Elision {
elide: Elide::Exact(elision_region),
s: self.scope
s: self.scope,
};
self.with(scope, |_old_scope, this| {
let scope = Scope::Binder {
@@ -716,12 +712,13 @@ fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
&trait_item.generics,
|this| intravisit::walk_trait_item(this, trait_item),
);
},
}
Type(ref bounds, ref ty) => {
let generics = &trait_item.generics;
let mut index = self.next_early_index();
debug!("visit_ty: index = {}", index);
let lifetimes = generics.lifetimes()
let lifetimes = generics
.lifetimes()
.map(|lt_def| Region::early(&self.tcx.hir, &mut index, lt_def))
.collect();
@@ -741,12 +738,12 @@ fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
this.visit_ty(ty);
}
});
},
}
Const(_, _) => {
// Only methods and types support generics.
assert!(trait_item.generics.params.is_empty());
intravisit::walk_trait_item(self, trait_item);
},
}
}
}
@@ -761,12 +758,13 @@ fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem) {
&impl_item.generics,
|this| intravisit::walk_impl_item(this, impl_item),
)
},
}
Type(ref ty) => {
let generics = &impl_item.generics;
let mut index = self.next_early_index();
debug!("visit_ty: index = {}", index);
let lifetimes = generics.lifetimes()
let lifetimes = generics
.lifetimes()
.map(|lt_def| Region::early(&self.tcx.hir, &mut index, lt_def))
.collect();
@@ -781,12 +779,12 @@ fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem) {
this.visit_generics(generics);
this.visit_ty(ty);
});
},
}
Const(_, _) => {
// Only methods and types support generics.
assert!(impl_item.generics.params.is_empty());
intravisit::walk_impl_item(self, impl_item);
},
}
}
}
@@ -822,7 +820,7 @@ fn visit_fn_decl(&mut self, fd: &'tcx hir::FnDecl) {
fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
check_mixed_explicit_and_in_band_defs(
self.tcx,
&generics.lifetimes().cloned().collect::<Vec<_>>()
&generics.lifetimes().cloned().collect::<Vec<_>>(),
);
for ty_param in generics.ty_params() {
walk_list!(self, visit_ty_param_bound, &ty_param.bounds);
@@ -842,7 +840,8 @@ fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
self.trait_ref_hack = true;
let next_early_index = self.next_early_index();
let scope = Scope::Binder {
lifetimes: bound_generic_params.lifetimes()
lifetimes: bound_generic_params
.lifetimes()
.map(|def| Region::late(&self.tcx.hir, def))
.collect(),
s: self.scope,
@@ -890,8 +889,11 @@ fn visit_poly_trait_ref(
) {
debug!("visit_poly_trait_ref trait_ref={:?}", trait_ref);
if !self.trait_ref_hack ||
trait_ref.bound_generic_params.iter().any(|p| p.is_lifetime_param())
if !self.trait_ref_hack
|| trait_ref
.bound_generic_params
.iter()
.any(|p| p.is_lifetime_param())
{
if self.trait_ref_hack {
span_err!(
@@ -903,7 +905,8 @@ fn visit_poly_trait_ref(
}
let next_early_index = self.next_early_index();
let scope = Scope::Binder {
lifetimes: trait_ref.bound_generic_params
lifetimes: trait_ref
.bound_generic_params
.lifetimes()
.map(|def| Region::late(&self.tcx.hir, def))
.collect(),
@@ -1144,7 +1147,8 @@ fn compute_object_lifetime_defaults(
.map(|set| match *set {
Set1::Empty => "BaseDefault".to_string(),
Set1::One(Region::Static) => "'static".to_string(),
Set1::One(Region::EarlyBound(i, _, _)) => generics.lifetimes()
Set1::One(Region::EarlyBound(i, _, _)) => generics
.lifetimes()
.nth(i as usize)
.unwrap()
.lifetime
@@ -1182,7 +1186,8 @@ fn add_bounds(set: &mut Set1<hir::LifetimeName>, bounds: &[hir::TyParamBound]) {
}
}
generics.ty_params()
generics
.ty_params()
.map(|param| {
let mut set = Set1::Empty;
@@ -1278,17 +1283,21 @@ fn with<F>(&mut self, wrap_scope: Scope, f: F)
if let hir::map::NodeLifetime(hir_lifetime) = this.tcx.hir.get(node_id) {
let span = hir_lifetime.span;
let id = hir_lifetime.id;
debug!("id ={:?} span = {:?} hir_lifetime = {:?}",
node_id,
span,
hir_lifetime);
debug!(
"id ={:?} span = {:?} hir_lifetime = {:?}",
node_id, span, hir_lifetime
);
this.tcx
.struct_span_lint_node(lint::builtin::SINGLE_USE_LIFETIME,
id,
span,
&format!("lifetime name `{}` only used once",
hir_lifetime.name.name()))
.struct_span_lint_node(
lint::builtin::SINGLE_USE_LIFETIME,
id,
span,
&format!(
"lifetime name `{}` only used once",
hir_lifetime.name.name()
),
)
.emit();
}
}
@@ -1379,8 +1388,10 @@ fn next_early_index_helper(&self, only_abstract_type_parent: bool) -> u32 {
next_early_index,
abstract_type_parent,
..
} if (!only_abstract_type_parent || abstract_type_parent)
=> return next_early_index,
} if (!only_abstract_type_parent || abstract_type_parent) =>
{
return next_early_index
}
Scope::Binder { s, .. }
| Scope::Body { s, .. }
@@ -1698,8 +1709,7 @@ fn visit_fn_like_elision(
}
// Foreign functions, `fn(...) -> R` and `Trait(...) -> R` (both types and bounds).
hir::map::NodeForeignItem(_) | hir::map::NodeTy(_) | hir::map::NodeTraitRef(_) =>
None,
hir::map::NodeForeignItem(_) | hir::map::NodeTy(_) | hir::map::NodeTraitRef(_) => None,
// Everything else (only closures?) doesn't
// actually enjoy elision in return types.
_ => {
@@ -1894,7 +1904,8 @@ fn resolve_elided_lifetimes(&mut self, lifetime_refs: &'tcx [hir::Lifetime], dep
lint::builtin::ELIDED_LIFETIME_IN_PATH,
id,
span,
&format!("hidden lifetime parameters are deprecated, try `Foo<'_>`"))
&format!("hidden lifetime parameters are deprecated, try `Foo<'_>`"),
)
.emit();
}
let error = loop {
@@ -1933,25 +1944,14 @@ fn resolve_elided_lifetimes(&mut self, lifetime_refs: &'tcx [hir::Lifetime], dep
}
};
let mut err = struct_span_err!(
self.tcx.sess,
span,
E0106,
"missing lifetime specifier{}",
if lifetime_refs.len() > 1 { "s" } else { "" }
);
let msg = if lifetime_refs.len() > 1 {
format!("expected {} lifetime parameters", lifetime_refs.len())
} else {
format!("expected lifetime parameter")
};
err.span_label(span, msg);
let mut err = report_missing_lifetime_specifiers(self.tcx.sess, span, lifetime_refs.len());
if let Some(params) = error {
if lifetime_refs.len() == 1 {
self.report_elision_failure(&mut err, params);
}
}
err.emit();
}
@@ -2086,7 +2086,8 @@ fn check_lifetime_params(&mut self, old_scope: ScopeRef, params: &'tcx [hir::Gen
);
err.emit();
}
hir::LifetimeName::Implicit | hir::LifetimeName::Name(_) => {}
hir::LifetimeName::Fresh(_) | hir::LifetimeName::Implicit |
hir::LifetimeName::Name(_) => {}
}
}
@@ -2138,7 +2139,8 @@ fn check_lifetime_params(&mut self, old_scope: ScopeRef, params: &'tcx [hir::Gen
))
.emit();
}
hir::LifetimeName::Implicit | hir::LifetimeName::Name(_) => {
hir::LifetimeName::Fresh(_) | hir::LifetimeName::Implicit |
hir::LifetimeName::Name(_) => {
self.resolve_lifetime_ref(bound);
}
}
@@ -2146,9 +2148,11 @@ fn check_lifetime_params(&mut self, old_scope: ScopeRef, params: &'tcx [hir::Gen
}
}
fn check_lifetime_def_for_shadowing(&self,
mut old_scope: ScopeRef,
lifetime: &'tcx hir::Lifetime) {
fn check_lifetime_def_for_shadowing(
&self,
mut old_scope: ScopeRef,
lifetime: &'tcx hir::Lifetime,
) {
for &(label, label_span) in &self.labels_in_fn {
// FIXME (#24278): non-hygienic comparison
if lifetime.name.name() == label {
@@ -2216,14 +2220,13 @@ fn insert_lifetime(&mut self, lifetime_ref: &'tcx hir::Lifetime, def: Region) {
self.map.defs.insert(lifetime_ref.id, def);
match def {
Region::LateBoundAnon(..) |
Region::Static => {
Region::LateBoundAnon(..) | Region::Static => {
// These are anonymous lifetimes or lifetimes that are not declared.
}
Region::Free(_, def_id) |
Region::LateBound(_, def_id, _) |
Region::EarlyBound(_, def_id, _) => {
Region::Free(_, def_id)
| Region::LateBound(_, def_id, _)
| Region::EarlyBound(_, def_id, _) => {
// A lifetime declared by the user.
if !self.lifetime_uses.contains_key(&def_id) {
self.lifetime_uses
@@ -2255,8 +2258,7 @@ fn insert_late_bound_lifetimes(
) {
debug!(
"insert_late_bound_lifetimes(decl={:?}, generics={:?})",
decl,
generics
decl, generics
);
let mut constrained_by_input = ConstrainedCollector {
@@ -2335,8 +2337,7 @@ fn insert_late_bound_lifetimes(
debug!(
"insert_late_bound_lifetimes: \
lifetime {:?} with id {:?} is late-bound",
lifetime.lifetime.name,
lifetime.lifetime.id
lifetime.lifetime.name, lifetime.lifetime.id
);
let inserted = map.late_bound.insert(lifetime.lifetime.id);
@@ -2403,3 +2404,27 @@ fn visit_lifetime(&mut self, lifetime_ref: &'v hir::Lifetime) {
}
}
}
pub fn report_missing_lifetime_specifiers(
sess: &Session,
span: Span,
count: usize,
) -> DiagnosticBuilder<'_> {
let mut err = struct_span_err!(
sess,
span,
E0106,
"missing lifetime specifier{}",
if count > 1 { "s" } else { "" }
);
let msg = if count > 1 {
format!("expected {} lifetime parameters", count)
} else {
format!("expected lifetime parameter")
};
err.span_label(span, msg);
err
}
src/test/ui/feature-gate-in_band_lifetimes-impl.rs
+22
View File
@@ -0,0 +1,22 @@
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![allow(warnings)]
#![feature(underscore_lifetimes)]
trait MyTrait<'a> { }
impl<'a> MyTrait<'a> for &u32 { }
//~^ ERROR missing lifetime specifier
impl<'a> MyTrait<'_> for &'a f32 { }
//~^ ERROR missing lifetime specifier
fn main() {}
src/test/ui/feature-gate-in_band_lifetimes-impl.stderr
+15
View File
@@ -0,0 +1,15 @@
error[E0106]: missing lifetime specifier
--> $DIR/feature-gate-in_band_lifetimes-impl.rs:16:26
|
LL | impl<'a> MyTrait<'a> for &u32 { }
| ^ expected lifetime parameter
error[E0106]: missing lifetime specifier
--> $DIR/feature-gate-in_band_lifetimes-impl.rs:19:18
|
LL | impl<'a> MyTrait<'_> for &'a f32 { }
| ^^ expected lifetime parameter
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0106`.
src/test/ui/in-band-lifetimes/impl/assoc-type.rs
+38
View File
@@ -0,0 +1,38 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test that we do not yet support elision in associated types, even
// when there is just one name we could take from the impl header.
#![allow(warnings)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
trait MyTrait {
type Output;
}
impl MyTrait for &i32 {
type Output = &i32;
//~^ ERROR missing lifetime specifier
}
impl MyTrait for &u32 {
type Output = &'_ i32;
//~^ ERROR missing lifetime specifier
}
// This is what you have to do:
impl MyTrait for &'a f32 {
type Output = &'a f32;
}
fn main() { }
src/test/ui/in-band-lifetimes/impl/assoc-type.stderr
+15
View File
@@ -0,0 +1,15 @@
error[E0106]: missing lifetime specifier
--> $DIR/assoc-type.rs:24:19
|
LL | type Output = &i32;
| ^ expected lifetime parameter
error[E0106]: missing lifetime specifier
--> $DIR/assoc-type.rs:29:20
|
LL | type Output = &'_ i32;
| ^^ expected lifetime parameter
error: aborting due to 2 previous errors
For more information about this error, try `rustc --explain E0106`.
src/test/ui/in-band-lifetimes/impl/dyn-trait.rs
+45
View File
@@ -0,0 +1,45 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test that `impl MyTrait<'_> for &i32` is equivalent to `impl<'a,
// 'b> MyTrait<'a> for &'b i32`.
#![allow(warnings)]
#![feature(dyn_trait)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
use std::fmt::Debug;
// Equivalent to `Box<dyn Debug + 'static>`:
trait StaticTrait { }
impl StaticTrait for Box<dyn Debug> { }
// Equivalent to `Box<dyn Debug + 'static>`:
trait NotStaticTrait { }
impl NotStaticTrait for Box<dyn Debug + '_> { }
fn static_val<T: StaticTrait>(_: T) {
}
fn with_dyn_debug_static<'a>(x: Box<dyn Debug + 'a>) {
static_val(x); //~ ERROR cannot infer
}
fn not_static_val<T: NotStaticTrait>(_: T) {
}
fn with_dyn_debug_not_static<'a>(x: Box<dyn Debug + 'a>) {
not_static_val(x); // OK
}
fn main() {
}
src/test/ui/in-band-lifetimes/impl/dyn-trait.stderr
+22
View File
@@ -0,0 +1,22 @@
error[E0495]: cannot infer an appropriate lifetime due to conflicting requirements
--> $DIR/dyn-trait.rs:34:16
|
LL | static_val(x); //~ ERROR cannot infer
| ^
|
note: first, the lifetime cannot outlive the lifetime 'a as defined on the function body at 33:1...
--> $DIR/dyn-trait.rs:33:1
|
LL | fn with_dyn_debug_static<'a>(x: Box<dyn Debug + 'a>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
= note: ...so that the expression is assignable:
expected std::boxed::Box<std::fmt::Debug>
found std::boxed::Box<std::fmt::Debug + 'a>
= note: but, the lifetime must be valid for the static lifetime...
= note: ...so that the types are compatible:
expected StaticTrait
found StaticTrait
error: aborting due to previous error
For more information about this error, try `rustc --explain E0495`.
src/test/ui/in-band-lifetimes/impl/path-elided.rs
+23
View File
@@ -0,0 +1,23 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![allow(warnings)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
trait MyTrait { }
struct Foo<'a> { x: &'a u32 }
impl MyTrait for Foo {
//~^ ERROR missing lifetime specifier
}
fn main() {}
src/test/ui/in-band-lifetimes/impl/path-elided.stderr
+9
View File
@@ -0,0 +1,9 @@
error[E0106]: missing lifetime specifier
--> $DIR/path-elided.rs:19:18
|
LL | impl MyTrait for Foo {
| ^^^ expected lifetime parameter
error: aborting due to previous error
For more information about this error, try `rustc --explain E0106`.
src/test/ui/in-band-lifetimes/impl/path-underscore.rs
+47
View File
@@ -0,0 +1,47 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test that `impl MyTrait for Foo<'_>` works.
// run-pass
#![allow(warnings)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
trait MyTrait { }
struct Foo<'a> { x: &'a u32 }
impl MyTrait for Foo<'_> {
}
fn impls_my_trait<T: MyTrait>() { }
fn impls_my_trait_val<T: MyTrait>(_: T) {
impls_my_trait::<T>();
}
fn random_where_clause()
where for<'a> Foo<'a>: MyTrait { }
fn main() {
let x = 22;
let f = Foo { x: &x };
// This type is `Foo<'x>` for a local lifetime `'x`; so the impl
// must apply to any lifetime to apply to this.
impls_my_trait_val(f);
impls_my_trait::<Foo<'static>>();
random_where_clause();
}
src/test/ui/in-band-lifetimes/impl/ref-underscore.rs
+43
View File
@@ -0,0 +1,43 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test that `impl MyTrait for &i32` works and is equivalent to any lifetime.
// run-pass
#![allow(warnings)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
trait MyTrait { }
impl MyTrait for &i32 {
}
fn impls_my_trait<T: MyTrait>() { }
fn impls_my_trait_val<T: MyTrait>(_: T) {
impls_my_trait::<T>();
}
fn random_where_clause()
where for<'a> &'a i32: MyTrait { }
fn main() {
let x = 22;
let f = &x;
impls_my_trait_val(f);
impls_my_trait::<&'static i32>();
random_where_clause();
}
src/test/ui/in-band-lifetimes/impl/trait-elided.rs
+21
View File
@@ -0,0 +1,21 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![allow(warnings)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
trait MyTrait<'a> { }
impl MyTrait for u32 {
//~^ ERROR missing lifetime specifier
}
fn main() {}
src/test/ui/in-band-lifetimes/impl/trait-elided.stderr
+9
View File
@@ -0,0 +1,9 @@
error[E0106]: missing lifetime specifier
--> $DIR/trait-elided.rs:17:6
|
LL | impl MyTrait for u32 {
| ^^^^^^^ expected lifetime parameter
error: aborting due to previous error
For more information about this error, try `rustc --explain E0106`.
src/test/ui/in-band-lifetimes/impl/trait-underscore.rs
+48
View File
@@ -0,0 +1,48 @@
// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Test that `impl MyTrait<'_> for &i32` is equivalent to `impl<'a,
// 'b> MyTrait<'a> for &'b i32`.
//
// run-pass
#![allow(warnings)]
#![feature(in_band_lifetimes)]
#![feature(underscore_lifetimes)]
trait MyTrait<'a> { }
// This is equivalent to `MyTrait<'a> for &'b i32`, which is proven by
// the code below.
impl MyTrait<'_> for &i32 {
}
// When called, T will be `&'x i32` for some `'x`, so since we can
// prove that `&'x i32: for<'a> MyTrait<'a>, then we know that the
// lifetime parameter above is disconnected.
fn impls_my_trait<T: for<'a> MyTrait<'a>>() { }
fn impls_my_trait_val<T: for<'a> MyTrait<'a>>(_: T) {
impls_my_trait::<T>();
}
fn random_where_clause()
where for<'a, 'b> &'a i32: MyTrait<'b> { }
fn main() {
let x = 22;
let f = &x;
impls_my_trait_val(f);
impls_my_trait::<&'static i32>();
random_where_clause();
}
src/test/ui/underscore-lifetime/dyn-trait-underscore-in-struct.rs
+26
View File
@@ -0,0 +1,26 @@
// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
// Check that the `'_` in `dyn Trait + '_` acts like ordinary elision,
// and not like an object lifetime default.
//
// cc #48468
#![feature(dyn_trait)]
#![feature(underscore_lifetimes)]
use std::fmt::Debug;
struct Foo {
x: Box<dyn Debug + '_>, //~ ERROR missing lifetime specifier
//~^ ERROR E0228
}
fn main() { }
src/test/ui/underscore-lifetime/dyn-trait-underscore-in-struct.stderr
+16
View File
@@ -0,0 +1,16 @@
error[E0106]: missing lifetime specifier
--> $DIR/dyn-trait-underscore-in-struct.rs:22:24
|
LL | x: Box<dyn Debug + '_>, //~ ERROR missing lifetime specifier
| ^^ expected lifetime parameter
error[E0228]: the lifetime bound for this object type cannot be deduced from context; please supply an explicit bound
--> $DIR/dyn-trait-underscore-in-struct.rs:22:12
|
LL | x: Box<dyn Debug + '_>, //~ ERROR missing lifetime specifier
| ^^^^^^^^^^^^^^
error: aborting due to 2 previous errors
Some errors occurred: E0106, E0228.
For more information about an error, try `rustc --explain E0106`.