23 files changed, 313 insertions, 193 deletions

diff --git a/crates/hir/src/code_model.rs b/crates/hir/src/code_model.rs
index 351ba75ff..fc1a74641 100644
--- a/crates/hir/src/code_model.rs
+++ b/crates/hir/src/code_model.rs
@@ -14,7 +14,7 @@ use hir_def::{
     per_ns::PerNs,
     resolver::{HasResolver, Resolver},
     src::HasSource as _,
-    type_ref::{Mutability, TypeRef},
+    type_ref::TypeRef,
     AdtId, AssocContainerId, AssocItemId, AssocItemLoc, AttrDefId, ConstId, ConstParamId,
     DefWithBodyId, EnumId, FunctionId, GenericDefId, HasModule, ImplId, LifetimeParamId,
     LocalEnumVariantId, LocalFieldId, Lookup, ModuleId, StaticId, StructId, TraitId, TypeAliasId,
@@ -31,9 +31,9 @@ use hir_ty::{
     display::{write_bounds_like_dyn_trait_with_prefix, HirDisplayError, HirFormatter},
     method_resolution,
     traits::{FnTrait, Solution, SolutionVariables},
-    BoundVar, CallableDefId, CallableSig, Canonical, DebruijnIndex, GenericPredicate,
-    InEnvironment, Obligation, ProjectionPredicate, ProjectionTy, Scalar, Substs, TraitEnvironment,
-    Ty, TyDefId, TyVariableKind,
+    AliasTy, BoundVar, CallableDefId, CallableSig, Canonical, DebruijnIndex, GenericPredicate,
+    InEnvironment, Mutability, Obligation, ProjectionPredicate, ProjectionTy, Scalar, Substs,
+    TraitEnvironment, Ty, TyDefId, TyVariableKind,
 };
 use rustc_hash::FxHashSet;
 use stdx::{format_to, impl_from};
@@ -836,7 +836,7 @@ pub enum Access {
 impl From<Mutability> for Access {
     fn from(mutability: Mutability) -> Access {
         match mutability {
-            Mutability::Shared => Access::Shared,
+            Mutability::Not => Access::Shared,
             Mutability::Mut => Access::Exclusive,
         }
     }
@@ -865,7 +865,10 @@ impl SelfParam {
             .params
             .first()
             .map(|param| match *param {
-                TypeRef::Reference(.., mutability) => mutability.into(),
+                TypeRef::Reference(.., mutability) => match mutability {
+                    hir_def::type_ref::Mutability::Shared => Access::Shared,
+                    hir_def::type_ref::Mutability::Mut => Access::Exclusive,
+                },
                 _ => Access::Owned,
             })
             .unwrap_or(Access::Owned)
@@ -1648,7 +1651,7 @@ impl Type {
             .build();
         let predicate = ProjectionPredicate {
             projection_ty: ProjectionTy { associated_ty: alias.id, parameters: subst },
-            ty: Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0)),
+            ty: Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0)),
         };
         let goal = Canonical {
             value: InEnvironment::new(
@@ -1709,7 +1712,7 @@ impl Type {
     }
 
     pub fn is_raw_ptr(&self) -> bool {
-        matches!(&self.ty.value, Ty::RawPtr(..))
+        matches!(&self.ty.value, Ty::Raw(..))
     }
 
     pub fn contains_unknown(&self) -> bool {
@@ -1937,7 +1940,7 @@ impl Type {
                         walk_bounds(db, &type_.derived(ty.clone()), &bounds, cb);
                     }
                 }
-                Ty::Opaque(opaque_ty) => {
+                Ty::Alias(AliasTy::Opaque(opaque_ty)) => {
                     if let Some(bounds) = ty.impl_trait_bounds(db) {
                         walk_bounds(db, &type_.derived(ty.clone()), &bounds, cb);
                     }
diff --git a/crates/hir_def/src/find_path.rs b/crates/hir_def/src/find_path.rs
index 5e2a711b8..3e19a7702 100644
--- a/crates/hir_def/src/find_path.rs
+++ b/crates/hir_def/src/find_path.rs
@@ -1,5 +1,7 @@
 //! An algorithm to find a path to refer to a certain item.
 
+use std::iter;
+
 use hir_expand::name::{known, AsName, Name};
 use rustc_hash::FxHashSet;
 use test_utils::mark;
@@ -95,7 +97,7 @@ fn find_path_inner(
     item: ItemInNs,
     from: ModuleId,
     max_len: usize,
-    prefixed: Option<PrefixKind>,
+    mut prefixed: Option<PrefixKind>,
 ) -> Option<ModPath> {
     if max_len == 0 {
         return None;
@@ -114,8 +116,9 @@ fn find_path_inner(
     }
 
     // - if the item is the crate root, return `crate`
-    let root = def_map.module_id(def_map.root());
+    let root = def_map.crate_root(db);
     if item == ItemInNs::Types(ModuleDefId::ModuleId(root)) && def_map.block_id().is_none() {
+        // FIXME: the `block_id()` check should be unnecessary, but affects the result
         return Some(ModPath::from_segments(PathKind::Crate, Vec::new()));
     }
 
@@ -165,7 +168,7 @@ fn find_path_inner(
 
     // - otherwise, look for modules containing (reexporting) it and import it from one of those
 
-    let crate_root = def_map.module_id(def_map.root());
+    let crate_root = def_map.crate_root(db);
     let crate_attrs = db.attrs(crate_root.into());
     let prefer_no_std = crate_attrs.by_key("no_std").exists();
     let mut best_path = None;
@@ -228,12 +231,16 @@ fn find_path_inner(
         }
     }
 
-    if let Some(mut prefix) = prefixed.map(PrefixKind::prefix) {
-        if matches!(prefix, PathKind::Crate | PathKind::Super(0)) && def_map.block_id().is_some() {
-            // Inner items cannot be referred to via `crate::` or `self::` paths.
-            prefix = PathKind::Plain;
+    // If the item is declared inside a block expression, don't use a prefix, as we don't handle
+    // that correctly (FIXME).
+    if let Some(item_module) = item.as_module_def_id().and_then(|did| did.module(db)) {
+        if item_module.def_map(db).block_id().is_some() && prefixed.is_some() {
+            mark::hit!(prefixed_in_block_expression);
+            prefixed = Some(PrefixKind::Plain);
         }
+    }
 
+    if let Some(prefix) = prefixed.map(PrefixKind::prefix) {
         best_path.or_else(|| {
             scope_name.map(|scope_name| ModPath::from_segments(prefix, vec![scope_name]))
         })
@@ -285,12 +292,12 @@ fn find_local_import_locations(
     let data = &def_map[from.local_id];
     let mut worklist =
         data.children.values().map(|child| def_map.module_id(*child)).collect::<Vec<_>>();
-    let mut parent = data.parent;
-    while let Some(p) = parent {
-        worklist.push(def_map.module_id(p));
-        parent = def_map[p].parent;
+    for ancestor in iter::successors(from.containing_module(db), |m| m.containing_module(db)) {
+        worklist.push(ancestor);
     }
 
+    let def_map = def_map.crate_root(db).def_map(db);
+
     let mut seen: FxHashSet<_> = FxHashSet::default();
 
     let mut locations = Vec::new();
@@ -301,7 +308,14 @@ fn find_local_import_locations(
 
         let ext_def_map;
         let data = if module.krate == from.krate {
-            &def_map[module.local_id]
+            if module.block.is_some() {
+                // Re-query the block's DefMap
+                ext_def_map = module.def_map(db);
+                &ext_def_map[module.local_id]
+            } else {
+                // Reuse the root DefMap
+                &def_map[module.local_id]
+            }
         } else {
             // The crate might reexport a module defined in another crate.
             ext_def_map = module.def_map(db);
@@ -828,6 +842,7 @@ mod tests {
 
     #[test]
     fn inner_items_from_inner_module() {
+        mark::check!(prefixed_in_block_expression);
         check_found_path(
             r#"
             fn main() {
@@ -869,4 +884,24 @@ mod tests {
             "super::Struct",
         );
     }
+
+    #[test]
+    fn outer_items_with_inner_items_present() {
+        check_found_path(
+            r#"
+            mod module {
+                pub struct CompleteMe;
+            }
+
+            fn main() {
+                fn inner() {}
+                $0
+            }
+            "#,
+            "module::CompleteMe",
+            "module::CompleteMe",
+            "crate::module::CompleteMe",
+            "self::module::CompleteMe",
+        )
+    }
 }
diff --git a/crates/hir_def/src/item_scope.rs b/crates/hir_def/src/item_scope.rs
index ee46c3330..4e5daa2ff 100644
--- a/crates/hir_def/src/item_scope.rs
+++ b/crates/hir_def/src/item_scope.rs
@@ -12,8 +12,8 @@ use stdx::format_to;
 use test_utils::mark;
 
 use crate::{
-    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, HasModule, ImplId,
-    LocalModuleId, Lookup, MacroDefId, ModuleDefId, ModuleId, TraitId,
+    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, ImplId,
+    LocalModuleId, MacroDefId, ModuleDefId, ModuleId, TraitId,
 };
 
 #[derive(Copy, Clone)]
@@ -375,19 +375,9 @@ impl ItemInNs {
 
     /// Returns the crate defining this item (or `None` if `self` is built-in).
     pub fn krate(&self, db: &dyn DefDatabase) -> Option<CrateId> {
-        Some(match self {
-            ItemInNs::Types(did) | ItemInNs::Values(did) => match did {
-                ModuleDefId::ModuleId(id) => id.krate,
-                ModuleDefId::FunctionId(id) => id.lookup(db).module(db).krate,
-                ModuleDefId::AdtId(id) => id.module(db).krate,
-                ModuleDefId::EnumVariantId(id) => id.parent.lookup(db).container.module(db).krate,
-                ModuleDefId::ConstId(id) => id.lookup(db).container.module(db).krate,
-                ModuleDefId::StaticId(id) => id.lookup(db).container.module(db).krate,
-                ModuleDefId::TraitId(id) => id.lookup(db).container.module(db).krate,
-                ModuleDefId::TypeAliasId(id) => id.lookup(db).module(db).krate,
-                ModuleDefId::BuiltinType(_) => return None,
-            },
-            ItemInNs::Macros(id) => return Some(id.krate),
-        })
+        match self {
+            ItemInNs::Types(did) | ItemInNs::Values(did) => did.module(db).map(|m| m.krate),
+            ItemInNs::Macros(id) => Some(id.krate),
+        }
     }
 }
diff --git a/crates/hir_def/src/lib.rs b/crates/hir_def/src/lib.rs
index 6802bc250..4498d94bb 100644
--- a/crates/hir_def/src/lib.rs
+++ b/crates/hir_def/src/lib.rs
@@ -97,6 +97,10 @@ impl ModuleId {
     pub fn krate(&self) -> CrateId {
         self.krate
     }
+
+    pub fn containing_module(&self, db: &dyn db::DefDatabase) -> Option<ModuleId> {
+        self.def_map(db).containing_module(self.local_id)
+    }
 }
 
 /// An ID of a module, **local** to a specific crate
@@ -529,6 +533,25 @@ impl HasModule for StaticLoc {
     }
 }
 
+impl ModuleDefId {
+    /// Returns the module containing `self` (or `self`, if `self` is itself a module).
+    ///
+    /// Returns `None` if `self` refers to a primitive type.
+    pub fn module(&self, db: &dyn db::DefDatabase) -> Option<ModuleId> {
+        Some(match self {
+            ModuleDefId::ModuleId(id) => *id,
+            ModuleDefId::FunctionId(id) => id.lookup(db).module(db),
+            ModuleDefId::AdtId(id) => id.module(db),
+            ModuleDefId::EnumVariantId(id) => id.parent.lookup(db).container.module(db),
+            ModuleDefId::ConstId(id) => id.lookup(db).container.module(db),
+            ModuleDefId::StaticId(id) => id.lookup(db).container.module(db),
+            ModuleDefId::TraitId(id) => id.lookup(db).container.module(db),
+            ModuleDefId::TypeAliasId(id) => id.lookup(db).module(db),
+            ModuleDefId::BuiltinType(_) => return None,
+        })
+    }
+}
+
 impl AttrDefId {
     pub fn krate(&self, db: &dyn db::DefDatabase) -> CrateId {
         match self {
diff --git a/crates/hir_def/src/nameres.rs b/crates/hir_def/src/nameres.rs
index 6a3456f2e..003d668ca 100644
--- a/crates/hir_def/src/nameres.rs
+++ b/crates/hir_def/src/nameres.rs
@@ -343,6 +343,18 @@ impl DefMap {
         Some(self.block?.parent)
     }
 
+    /// Returns the module containing `local_mod`, either the parent `mod`, or the module containing
+    /// the block, if `self` corresponds to a block expression.
+    pub fn containing_module(&self, local_mod: LocalModuleId) -> Option<ModuleId> {
+        match &self[local_mod].parent {
+            Some(parent) => Some(self.module_id(*parent)),
+            None => match &self.block {
+                Some(block) => Some(block.parent),
+                None => None,
+            },
+        }
+    }
+
     // FIXME: this can use some more human-readable format (ideally, an IR
     // even), as this should be a great debugging aid.
     pub fn dump(&self, db: &dyn DefDatabase) -> String {
diff --git a/crates/hir_def/src/path/lower.rs b/crates/hir_def/src/path/lower.rs
index a469546c1..505493a74 100644
--- a/crates/hir_def/src/path/lower.rs
+++ b/crates/hir_def/src/path/lower.rs
@@ -101,8 +101,12 @@ pub(super) fn lower_path(mut path: ast::Path, hygiene: &Hygiene) -> Option<Path>
                 break;
             }
             ast::PathSegmentKind::SelfKw => {
-                kind = PathKind::Super(0);
-                break;
+                // don't break out if `self` is the last segment of a path, this mean we got an
+                // use tree like `foo::{self}` which we want to resolve as `foo`
+                if !segments.is_empty() {
+                    kind = PathKind::Super(0);
+                    break;
+                }
             }
             ast::PathSegmentKind::SuperKw => {
                 let nested_super_count = if let PathKind::Super(n) = kind { n } else { 0 };
@@ -117,6 +121,11 @@ pub(super) fn lower_path(mut path: ast::Path, hygiene: &Hygiene) -> Option<Path>
     segments.reverse();
     generic_args.reverse();
 
+    if segments.is_empty() && kind == PathKind::Plain && type_anchor.is_none() {
+        // plain empty paths don't exist, this means we got a single `self` segment as our path
+        kind = PathKind::Super(0);
+    }
+
     // handle local_inner_macros :
     // Basically, even in rustc it is quite hacky:
     // https://github.com/rust-lang/rust/blob/614f273e9388ddd7804d5cbc80b8865068a3744e/src/librustc_resolve/macros.rs#L456
diff --git a/crates/hir_ty/Cargo.toml b/crates/hir_ty/Cargo.toml
index 6ef9d1e7e..d1302d749 100644
--- a/crates/hir_ty/Cargo.toml
+++ b/crates/hir_ty/Cargo.toml
@@ -17,9 +17,9 @@ ena = "0.14.0"
 log = "0.4.8"
 rustc-hash = "1.1.0"
 scoped-tls = "1"
-chalk-solve = { version = "0.58", default-features = false }
-chalk-ir = "0.58"
-chalk-recursive = "0.58"
+chalk-solve = { version = "0.59", default-features = false }
+chalk-ir = "0.59"
+chalk-recursive = "0.59"
 la-arena = { version = "0.2.0", path = "../../lib/arena" }
 
 stdx = { path = "../stdx", version = "0.0.0" }
diff --git a/crates/hir_ty/src/autoderef.rs b/crates/hir_ty/src/autoderef.rs
index 21d1e5446..be1fd1f13 100644
--- a/crates/hir_ty/src/autoderef.rs
+++ b/crates/hir_ty/src/autoderef.rs
@@ -81,7 +81,7 @@ fn deref_by_trait(
 
     // Now do the assoc type projection
     let projection = super::traits::ProjectionPredicate {
-        ty: Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, ty.value.kinds.len())),
+        ty: Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, ty.value.kinds.len())),
         projection_ty: super::ProjectionTy { associated_ty: target, parameters },
     };
 
@@ -114,7 +114,8 @@ fn deref_by_trait(
             // new variables in that case
 
             for i in 1..vars.0.kinds.len() {
-                if vars.0.value[i - 1] != Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, i - 1))
+                if vars.0.value[i - 1]
+                    != Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, i - 1))
                 {
                     warn!("complex solution for derefing {:?}: {:?}, ignoring", ty.value, solution);
                     return None;
diff --git a/crates/hir_ty/src/diagnostics/unsafe_check.rs b/crates/hir_ty/src/diagnostics/unsafe_check.rs
index b439915c7..e77a20fea 100644
--- a/crates/hir_ty/src/diagnostics/unsafe_check.rs
+++ b/crates/hir_ty/src/diagnostics/unsafe_check.rs
@@ -110,7 +110,7 @@ fn walk_unsafe(
             }
         }
         Expr::UnaryOp { expr, op: UnaryOp::Deref } => {
-            if let Ty::RawPtr(..) = &infer[*expr] {
+            if let Ty::Raw(..) = &infer[*expr] {
                 unsafe_exprs.push(UnsafeExpr { expr: current, inside_unsafe_block });
             }
         }
diff --git a/crates/hir_ty/src/display.rs b/crates/hir_ty/src/display.rs
index ff8211094..d4a8b48e6 100644
--- a/crates/hir_ty/src/display.rs
+++ b/crates/hir_ty/src/display.rs
@@ -3,10 +3,12 @@
 use std::{borrow::Cow, fmt};
 
 use crate::{
-    db::HirDatabase, primitive, utils::generics, CallableDefId, CallableSig, GenericPredicate,
-    Lifetime, Obligation, OpaqueTy, OpaqueTyId, ProjectionTy, Scalar, Substs, TraitRef, Ty,
+    db::HirDatabase, primitive, utils::generics, AliasTy, CallableDefId, CallableSig,
+    GenericPredicate, Lifetime, Obligation, OpaqueTy, OpaqueTyId, ProjectionTy, Scalar, Substs,
+    TraitRef, Ty,
 };
 use arrayvec::ArrayVec;
+use chalk_ir::Mutability;
 use hir_def::{
     db::DefDatabase, find_path, generics::TypeParamProvenance, item_scope::ItemInNs, AdtId,
     AssocContainerId, HasModule, Lookup, ModuleId, TraitId,
@@ -284,15 +286,29 @@ impl HirDisplay for Ty {
                 t.hir_fmt(f)?;
                 write!(f, "; _]")?;
             }
-            Ty::RawPtr(m, parameters) | Ty::Ref(m, parameters) => {
+            Ty::Raw(m, parameters) | Ty::Ref(m, parameters) => {
                 let t = parameters.as_single();
                 let ty_display =
                     t.into_displayable(f.db, f.max_size, f.omit_verbose_types, f.display_target);
 
-                if matches!(self, Ty::RawPtr(..)) {
-                    write!(f, "*{}", m.as_keyword_for_ptr())?;
+                if matches!(self, Ty::Raw(..)) {
+                    write!(
+                        f,
+                        "*{}",
+                        match m {
+                            Mutability::Not => "const ",
+                            Mutability::Mut => "mut ",
+                        }
+                    )?;
                 } else {
-                    write!(f, "&{}", m.as_keyword_for_ref())?;
+                    write!(
+                        f,
+                        "&{}",
+                        match m {
+                            Mutability::Not => "",
+                            Mutability::Mut => "mut ",
+                        }
+                    )?;
                 }
 
                 let datas;
@@ -300,10 +316,10 @@ impl HirDisplay for Ty {
                     Ty::Dyn(predicates) if predicates.len() > 1 => {
                         Cow::Borrowed(predicates.as_ref())
                     }
-                    &Ty::Opaque(OpaqueTy {
+                    &Ty::Alias(AliasTy::Opaque(OpaqueTy {
                         opaque_ty_id: OpaqueTyId::ReturnTypeImplTrait(func, idx),
                         ref parameters,
-                    }) => {
+                    })) => {
                         datas =
                             f.db.return_type_impl_traits(func).expect("impl trait id without data");
                         let data = (*datas)
@@ -518,7 +534,6 @@ impl HirDisplay for Ty {
                     write!(f, "{{closure}}")?;
                 }
             }
-            Ty::Projection(p_ty) => p_ty.hir_fmt(f)?,
             Ty::Placeholder(id) => {
                 let generics = generics(f.db.upcast(), id.parent);
                 let param_data = &generics.params.types[id.local_id];
@@ -537,11 +552,12 @@ impl HirDisplay for Ty {
                     }
                 }
             }
-            Ty::Bound(idx) => write!(f, "?{}.{}", idx.debruijn.depth(), idx.index)?,
+            Ty::BoundVar(idx) => write!(f, "?{}.{}", idx.debruijn.depth(), idx.index)?,
             Ty::Dyn(predicates) => {
                 write_bounds_like_dyn_trait_with_prefix("dyn", predicates, f)?;
             }
-            Ty::Opaque(opaque_ty) => {
+            Ty::Alias(AliasTy::Projection(p_ty)) => p_ty.hir_fmt(f)?,
+            Ty::Alias(AliasTy::Opaque(opaque_ty)) => {
                 match opaque_ty.opaque_ty_id {
                     OpaqueTyId::ReturnTypeImplTrait(func, idx) => {
                         let datas =
diff --git a/crates/hir_ty/src/infer.rs b/crates/hir_ty/src/infer.rs
index 1d78d1feb..4d771a91e 100644
--- a/crates/hir_ty/src/infer.rs
+++ b/crates/hir_ty/src/infer.rs
@@ -18,6 +18,7 @@ use std::mem;
 use std::ops::Index;
 use std::sync::Arc;
 
+use chalk_ir::Mutability;
 use hir_def::{
     body::Body,
     data::{ConstData, FunctionData, StaticData},
@@ -25,7 +26,7 @@ use hir_def::{
     lang_item::LangItemTarget,
     path::{path, Path},
     resolver::{HasResolver, Resolver, TypeNs},
-    type_ref::{Mutability, TypeRef},
+    type_ref::TypeRef,
     AdtId, AssocItemId, DefWithBodyId, EnumVariantId, FieldId, FunctionId, Lookup, TraitId,
     TypeAliasId, VariantId,
 };
@@ -40,7 +41,7 @@ use super::{
     InEnvironment, ProjectionTy, Substs, TraitEnvironment, TraitRef, Ty, TypeWalk,
 };
 use crate::{
-    db::HirDatabase, infer::diagnostics::InferenceDiagnostic, lower::ImplTraitLoweringMode,
+    db::HirDatabase, infer::diagnostics::InferenceDiagnostic, lower::ImplTraitLoweringMode, AliasTy,
 };
 
 pub(crate) use unify::unify;
@@ -87,7 +88,7 @@ impl BindingMode {
     fn convert(annotation: BindingAnnotation) -> BindingMode {
         match annotation {
             BindingAnnotation::Unannotated | BindingAnnotation::Mutable => BindingMode::Move,
-            BindingAnnotation::Ref => BindingMode::Ref(Mutability::Shared),
+            BindingAnnotation::Ref => BindingMode::Ref(Mutability::Not),
             BindingAnnotation::RefMut => BindingMode::Ref(Mutability::Mut),
         }
     }
@@ -395,7 +396,7 @@ impl<'a> InferenceContext<'a> {
     fn normalize_associated_types_in(&mut self, ty: Ty) -> Ty {
         let ty = self.resolve_ty_as_possible(ty);
         ty.fold(&mut |ty| match ty {
-            Ty::Projection(proj_ty) => self.normalize_projection_ty(proj_ty),
+            Ty::Alias(AliasTy::Projection(proj_ty)) => self.normalize_projection_ty(proj_ty),
             _ => ty,
         })
     }
diff --git a/crates/hir_ty/src/infer/coerce.rs b/crates/hir_ty/src/infer/coerce.rs
index 667b26a76..cf0a3add4 100644
--- a/crates/hir_ty/src/infer/coerce.rs
+++ b/crates/hir_ty/src/infer/coerce.rs
@@ -4,8 +4,8 @@
 //!
 //! See: https://doc.rust-lang.org/nomicon/coercions.html
 
-use chalk_ir::TyVariableKind;
-use hir_def::{lang_item::LangItemTarget, type_ref::Mutability};
+use chalk_ir::{Mutability, TyVariableKind};
+use hir_def::lang_item::LangItemTarget;
 use test_utils::mark;
 
 use crate::{autoderef, traits::Solution, Obligation, Substs, TraitRef, Ty};
@@ -73,20 +73,20 @@ impl<'a> InferenceContext<'a> {
         match (&mut from_ty, to_ty) {
             // `*mut T` -> `*const T`
             // `&mut T` -> `&T`
-            (Ty::RawPtr(m1, ..), Ty::RawPtr(m2 @ Mutability::Shared, ..))
-            | (Ty::Ref(m1, ..), Ty::Ref(m2 @ Mutability::Shared, ..)) => {
+            (Ty::Raw(m1, ..), Ty::Raw(m2 @ Mutability::Not, ..))
+            | (Ty::Ref(m1, ..), Ty::Ref(m2 @ Mutability::Not, ..)) => {
                 *m1 = *m2;
             }
             // `&T` -> `*const T`
             // `&mut T` -> `*mut T`/`*const T`
-            (Ty::Ref(.., substs), &Ty::RawPtr(m2 @ Mutability::Shared, ..))
-            | (Ty::Ref(Mutability::Mut, substs), &Ty::RawPtr(m2, ..)) => {
-                from_ty = Ty::RawPtr(m2, substs.clone());
+            (Ty::Ref(.., substs), &Ty::Raw(m2 @ Mutability::Not, ..))
+            | (Ty::Ref(Mutability::Mut, substs), &Ty::Raw(m2, ..)) => {
+                from_ty = Ty::Raw(m2, substs.clone());
             }
 
             // Illegal mutability conversion
-            (Ty::RawPtr(Mutability::Shared, ..), Ty::RawPtr(Mutability::Mut, ..))
-            | (Ty::Ref(Mutability::Shared, ..), Ty::Ref(Mutability::Mut, ..)) => return false,
+            (Ty::Raw(Mutability::Not, ..), Ty::Raw(Mutability::Mut, ..))
+            | (Ty::Ref(Mutability::Not, ..), Ty::Ref(Mutability::Mut, ..)) => return false,
 
             // `{function_type}` -> `fn()`
             (Ty::FnDef(..), Ty::Function { .. }) => match from_ty.callable_sig(self.db) {
diff --git a/crates/hir_ty/src/infer/expr.rs b/crates/hir_ty/src/infer/expr.rs
index 928ad37a3..cf1f1038a 100644
--- a/crates/hir_ty/src/infer/expr.rs
+++ b/crates/hir_ty/src/infer/expr.rs
@@ -3,7 +3,7 @@
 use std::iter::{repeat, repeat_with};
 use std::{mem, sync::Arc};
 
-use chalk_ir::TyVariableKind;
+use chalk_ir::{Mutability, TyVariableKind};
 use hir_def::{
     expr::{Array, BinaryOp, Expr, ExprId, Literal, Statement, UnaryOp},
     path::{GenericArg, GenericArgs},
@@ -15,12 +15,14 @@ use syntax::ast::RangeOp;
 use test_utils::mark;
 
 use crate::{
-    autoderef, method_resolution, op,
+    autoderef,
+    lower::lower_to_chalk_mutability,
+    method_resolution, op,
     primitive::{self, UintTy},
     traits::{FnTrait, InEnvironment},
     utils::{generics, variant_data, Generics},
-    Binders, CallableDefId, FnPointer, FnSig, Mutability, Obligation, OpaqueTyId, Rawness, Scalar,
-    Substs, TraitRef, Ty,
+    Binders, CallableDefId, FnPointer, FnSig, Obligation, OpaqueTyId, Rawness, Scalar, Substs,
+    TraitRef, Ty,
 };
 
 use super::{
@@ -462,10 +464,11 @@ impl<'a> InferenceContext<'a> {
                 cast_ty
             }
             Expr::Ref { expr, rawness, mutability } => {
+                let mutability = lower_to_chalk_mutability(*mutability);
                 let expectation = if let Some((exp_inner, exp_rawness, exp_mutability)) =
                     &expected.ty.as_reference_or_ptr()
                 {
-                    if *exp_mutability == Mutability::Mut && *mutability == Mutability::Shared {
+                    if *exp_mutability == Mutability::Mut && mutability == Mutability::Not {
                         // FIXME: throw type error - expected mut reference but found shared ref,
                         // which cannot be coerced
                     }
@@ -479,8 +482,8 @@ impl<'a> InferenceContext<'a> {
                 };
                 let inner_ty = self.infer_expr_inner(*expr, &expectation);
                 match rawness {
-                    Rawness::RawPtr => Ty::RawPtr(*mutability, Substs::single(inner_ty)),
-                    Rawness::Ref => Ty::Ref(*mutability, Substs::single(inner_ty)),
+                    Rawness::RawPtr => Ty::Raw(mutability, Substs::single(inner_ty)),
+                    Rawness::Ref => Ty::Ref(mutability, Substs::single(inner_ty)),
                 }
             }
             Expr::Box { expr } => {
@@ -684,11 +687,11 @@ impl<'a> InferenceContext<'a> {
             }
             Expr::Literal(lit) => match lit {
                 Literal::Bool(..) => Ty::Scalar(Scalar::Bool),
-                Literal::String(..) => Ty::Ref(Mutability::Shared, Substs::single(Ty::Str)),
+                Literal::String(..) => Ty::Ref(Mutability::Not, Substs::single(Ty::Str)),
                 Literal::ByteString(..) => {
                     let byte_type = Ty::Scalar(Scalar::Uint(UintTy::U8));
                     let array_type = Ty::Array(Substs::single(byte_type));
-                    Ty::Ref(Mutability::Shared, Substs::single(array_type))
+                    Ty::Ref(Mutability::Not, Substs::single(array_type))
                 }
                 Literal::Char(..) => Ty::Scalar(Scalar::Char),
                 Literal::Int(_v, ty) => match ty {
diff --git a/crates/hir_ty/src/infer/pat.rs b/crates/hir_ty/src/infer/pat.rs
index a318e47f3..eb099311c 100644
--- a/crates/hir_ty/src/infer/pat.rs
+++ b/crates/hir_ty/src/infer/pat.rs
@@ -3,17 +3,17 @@
 use std::iter::repeat;
 use std::sync::Arc;
 
+use chalk_ir::Mutability;
 use hir_def::{
     expr::{BindingAnnotation, Expr, Literal, Pat, PatId, RecordFieldPat},
     path::Path,
-    type_ref::Mutability,
     FieldId,
 };
 use hir_expand::name::Name;
 use test_utils::mark;
 
 use super::{BindingMode, Expectation, InferenceContext};
-use crate::{utils::variant_data, Substs, Ty};
+use crate::{lower::lower_to_chalk_mutability, utils::variant_data, Substs, Ty};
 
 impl<'a> InferenceContext<'a> {
     fn infer_tuple_struct_pat(
@@ -103,7 +103,7 @@ impl<'a> InferenceContext<'a> {
                 expected = inner;
                 default_bm = match default_bm {
                     BindingMode::Move => BindingMode::Ref(mutability),
-                    BindingMode::Ref(Mutability::Shared) => BindingMode::Ref(Mutability::Shared),
+                    BindingMode::Ref(Mutability::Not) => BindingMode::Ref(Mutability::Not),
                     BindingMode::Ref(Mutability::Mut) => BindingMode::Ref(mutability),
                 }
             }
@@ -152,9 +152,10 @@ impl<'a> InferenceContext<'a> {
                 }
             }
             Pat::Ref { pat, mutability } => {
+                let mutability = lower_to_chalk_mutability(*mutability);
                 let expectation = match expected.as_reference() {
                     Some((inner_ty, exp_mut)) => {
-                        if *mutability != exp_mut {
+                        if mutability != exp_mut {
                             // FIXME: emit type error?
                         }
                         inner_ty
@@ -162,7 +163,7 @@ impl<'a> InferenceContext<'a> {
                     _ => &Ty::Unknown,
                 };
                 let subty = self.infer_pat(*pat, expectation, default_bm);
-                Ty::Ref(*mutability, Substs::single(subty))
+                Ty::Ref(mutability, Substs::single(subty))
             }
             Pat::TupleStruct { path: p, args: subpats, ellipsis } => self.infer_tuple_struct_pat(
                 p.as_ref(),
diff --git a/crates/hir_ty/src/infer/unify.rs b/crates/hir_ty/src/infer/unify.rs
index b481aa1b3..99a89a7f3 100644
--- a/crates/hir_ty/src/infer/unify.rs
+++ b/crates/hir_ty/src/infer/unify.rs
@@ -68,7 +68,7 @@ impl<'a, 'b> Canonicalizer<'a, 'b> {
                     } else {
                         let root = self.ctx.table.var_unification_table.find(inner);
                         let position = self.add(InferenceVar::from_inner(root), kind);
-                        Ty::Bound(BoundVar::new(binders, position))
+                        Ty::BoundVar(BoundVar::new(binders, position))
                     }
                 }
                 _ => ty,
@@ -110,7 +110,7 @@ impl<T> Canonicalized<T> {
     pub(super) fn decanonicalize_ty(&self, mut ty: Ty) -> Ty {
         ty.walk_mut_binders(
             &mut |ty, binders| {
-                if let &mut Ty::Bound(bound) = ty {
+                if let &mut Ty::BoundVar(bound) = ty {
                     if bound.debruijn >= binders {
                         let (v, k) = self.free_vars[bound.index];
                         *ty = Ty::InferenceVar(v, k);
@@ -168,7 +168,7 @@ pub(crate) fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substs> {
     // (kind of hacky)
     for (i, var) in vars.iter().enumerate() {
         if &*table.resolve_ty_shallow(var) == var {
-            table.unify(var, &Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, i)));
+            table.unify(var, &Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, i)));
         }
     }
     Some(
diff --git a/crates/hir_ty/src/lib.rs b/crates/hir_ty/src/lib.rs
index 1131eaf92..c2a20c480 100644
--- a/crates/hir_ty/src/lib.rs
+++ b/crates/hir_ty/src/lib.rs
@@ -27,11 +27,9 @@ use std::{iter, mem, ops::Deref, sync::Arc};
 
 use base_db::salsa;
 use hir_def::{
-    builtin_type::BuiltinType,
-    expr::ExprId,
-    type_ref::{Mutability, Rawness},
-    AdtId, AssocContainerId, DefWithBodyId, FunctionId, GenericDefId, HasModule, LifetimeParamId,
-    Lookup, TraitId, TypeAliasId, TypeParamId,
+    builtin_type::BuiltinType, expr::ExprId, type_ref::Rawness, AdtId, AssocContainerId,
+    DefWithBodyId, FunctionId, GenericDefId, HasModule, LifetimeParamId, Lookup, TraitId,
+    TypeAliasId, TypeParamId,
 };
 use itertools::Itertools;
 
@@ -49,7 +47,7 @@ pub use lower::{
 };
 pub use traits::{InEnvironment, Obligation, ProjectionPredicate, TraitEnvironment};
 
-pub use chalk_ir::{BoundVar, DebruijnIndex, Scalar, TyVariableKind};
+pub use chalk_ir::{BoundVar, DebruijnIndex, Mutability, Scalar, TyVariableKind};
 
 #[derive(Clone, PartialEq, Eq, Debug, Hash)]
 pub enum Lifetime {
@@ -111,6 +109,19 @@ pub struct FnPointer {
     pub substs: Substs,
 }
 
+#[derive(Clone, PartialEq, Eq, Debug, Hash)]
+pub enum AliasTy {
+    /// A "projection" type corresponds to an (unnormalized)
+    /// projection like `<P0 as Trait<P1..Pn>>::Foo`. Note that the
+    /// trait and all its parameters are fully known.
+    Projection(ProjectionTy),
+    /// An opaque type (`impl Trait`).
+    ///
+    /// This is currently only used for return type impl trait; each instance of
+    /// `impl Trait` in a return type gets its own ID.
+    Opaque(OpaqueTy),
+}
+
 /// A type.
 ///
 /// See also the `TyKind` enum in rustc (librustc/ty/sty.rs), which represents
@@ -141,7 +152,7 @@ pub enum Ty {
     Slice(Substs),
 
     /// A raw pointer. Written as `*mut T` or `*const T`
-    RawPtr(Mutability, Substs),
+    Raw(Mutability, Substs),
 
     /// A reference; a pointer with an associated lifetime. Written as
     /// `&'a mut T` or `&'a T`.
@@ -193,16 +204,11 @@ pub enum Ty {
     /// ```
     Function(FnPointer),
 
-    /// A "projection" type corresponds to an (unnormalized)
-    /// projection like `<P0 as Trait<P1..Pn>>::Foo`. Note that the
-    /// trait and all its parameters are fully known.
-    Projection(ProjectionTy),
-
-    /// An opaque type (`impl Trait`).
-    ///
-    /// This is currently only used for return type impl trait; each instance of
-    /// `impl Trait` in a return type gets its own ID.
-    Opaque(OpaqueTy),
+    /// An "alias" type represents some form of type alias, such as:
+    /// - An associated type projection like `<T as Iterator>::Item`
+    /// - `impl Trait` types
+    /// - Named type aliases like `type Foo<X> = Vec<X>`
+    Alias(AliasTy),
 
     /// A placeholder for a type parameter; for example, `T` in `fn f<T>(x: T)
     /// {}` when we're type-checking the body of that function. In this
@@ -215,7 +221,7 @@ pub enum Ty {
     /// parameters get turned into variables; during trait resolution, inference
     /// variables get turned into bound variables and back; and in `Dyn` the
     /// `Self` type is represented with a bound variable as well.
-    Bound(BoundVar),
+    BoundVar(BoundVar),
 
     /// A type variable used during type checking.
     InferenceVar(InferenceVar, TyVariableKind),
@@ -299,7 +305,7 @@ impl Substs {
             generic_params
                 .iter()
                 .enumerate()
-                .map(|(idx, _)| Ty::Bound(BoundVar::new(debruijn, idx)))
+                .map(|(idx, _)| Ty::BoundVar(BoundVar::new(debruijn, idx)))
                 .collect(),
         )
     }
@@ -347,7 +353,7 @@ impl SubstsBuilder {
     }
 
     pub fn fill_with_bound_vars(self, debruijn: DebruijnIndex, starting_from: usize) -> Self {
-        self.fill((starting_from..).map(|idx| Ty::Bound(BoundVar::new(debruijn, idx))))
+        self.fill((starting_from..).map(|idx| Ty::BoundVar(BoundVar::new(debruijn, idx))))
     }
 
     pub fn fill_with_unknown(self) -> Self {
@@ -627,7 +633,7 @@ impl Ty {
             Ty::Ref(mutability, parameters) => {
                 Some((parameters.as_single(), Rawness::Ref, *mutability))
             }
-            Ty::RawPtr(mutability, parameters) => {
+            Ty::Raw(mutability, parameters) => {
                 Some((parameters.as_single(), Rawness::RawPtr, *mutability))
             }
             _ => None,
@@ -688,9 +694,7 @@ impl Ty {
                 expr == expr2 && def == def2
             }
             (Ty::Ref(mutability, ..), Ty::Ref(mutability2, ..))
-            | (Ty::RawPtr(mutability, ..), Ty::RawPtr(mutability2, ..)) => {
-                mutability == mutability2
-            }
+            | (Ty::Raw(mutability, ..), Ty::Raw(mutability2, ..)) => mutability == mutability2,
             (
                 Ty::Function(FnPointer { num_args, sig, .. }),
                 Ty::Function(FnPointer { num_args: num_args2, sig: sig2, .. }),
@@ -721,7 +725,7 @@ impl Ty {
     fn builtin_deref(&self) -> Option<Ty> {
         match self {
             Ty::Ref(.., parameters) => Some(Ty::clone(parameters.as_single())),
-            Ty::RawPtr(.., parameters) => Some(Ty::clone(parameters.as_single())),
+            Ty::Raw(.., parameters) => Some(Ty::clone(parameters.as_single())),
             _ => None,
         }
     }
@@ -757,7 +761,7 @@ impl Ty {
             Ty::Adt(_, substs)
             | Ty::Slice(substs)
             | Ty::Array(substs)
-            | Ty::RawPtr(_, substs)
+            | Ty::Raw(_, substs)
             | Ty::Ref(_, substs)
             | Ty::FnDef(_, substs)
             | Ty::Function(FnPointer { substs, .. })
@@ -780,7 +784,7 @@ impl Ty {
             Ty::Adt(_, substs)
             | Ty::Slice(substs)
             | Ty::Array(substs)
-            | Ty::RawPtr(_, substs)
+            | Ty::Raw(_, substs)
             | Ty::Ref(_, substs)
             | Ty::FnDef(_, substs)
             | Ty::Function(FnPointer { substs, .. })
@@ -797,7 +801,7 @@ impl Ty {
             Ty::Adt(_, substs)
             | Ty::Slice(substs)
             | Ty::Array(substs)
-            | Ty::RawPtr(_, substs)
+            | Ty::Raw(_, substs)
             | Ty::Ref(_, substs)
             | Ty::FnDef(_, substs)
             | Ty::Function(FnPointer { substs, .. })
@@ -834,7 +838,7 @@ impl Ty {
                     OpaqueTyId::ReturnTypeImplTrait(..) => None,
                 }
             }
-            Ty::Opaque(opaque_ty) => {
+            Ty::Alias(AliasTy::Opaque(opaque_ty)) => {
                 let predicates = match opaque_ty.opaque_ty_id {
                     OpaqueTyId::ReturnTypeImplTrait(func, idx) => {
                         db.return_type_impl_traits(func).map(|it| {
@@ -878,7 +882,7 @@ impl Ty {
                     _ => None,
                 }
             }
-            Ty::Projection(projection_ty) => {
+            Ty::Alias(AliasTy::Projection(projection_ty)) => {
                 match projection_ty.associated_ty.lookup(db.upcast()).container {
                     AssocContainerId::TraitId(trait_id) => Some(trait_id),
                     _ => None,
@@ -956,7 +960,7 @@ pub trait TypeWalk {
     {
         self.walk_mut_binders(
             &mut |ty, binders| {
-                if let &mut Ty::Bound(bound) = ty {
+                if let &mut Ty::BoundVar(bound) = ty {
                     if bound.debruijn >= binders {
                         *ty = substs.0[bound.index].clone().shift_bound_vars(binders);
                     }
@@ -974,8 +978,8 @@ pub trait TypeWalk {
     {
         self.fold_binders(
             &mut |ty, binders| match ty {
-                Ty::Bound(bound) if bound.debruijn >= binders => {
-                    Ty::Bound(bound.shifted_in_from(n))
+                Ty::BoundVar(bound) if bound.debruijn >= binders => {
+                    Ty::BoundVar(bound.shifted_in_from(n))
                 }
                 ty => ty,
             },
@@ -987,21 +991,21 @@ pub trait TypeWalk {
 impl TypeWalk for Ty {
     fn walk(&self, f: &mut impl FnMut(&Ty)) {
         match self {
-            Ty::Projection(p_ty) => {
+            Ty::Alias(AliasTy::Projection(p_ty)) => {
                 for t in p_ty.parameters.iter() {
                     t.walk(f);
                 }
             }
+            Ty::Alias(AliasTy::Opaque(o_ty)) => {
+                for t in o_ty.parameters.iter() {
+                    t.walk(f);
+                }
+            }
             Ty::Dyn(predicates) => {
                 for p in predicates.iter() {
                     p.walk(f);
                 }
             }
-            Ty::Opaque(o_ty) => {
-                for t in o_ty.parameters.iter() {
-                    t.walk(f);
-                }
-            }
             _ => {
                 if let Some(substs) = self.substs() {
                     for t in substs.iter() {
@@ -1019,7 +1023,7 @@ impl TypeWalk for Ty {
         binders: DebruijnIndex,
     ) {
         match self {
-            Ty::Projection(p_ty) => {
+            Ty::Alias(AliasTy::Projection(p_ty)) => {
                 p_ty.parameters.walk_mut_binders(f, binders);
             }
             Ty::Dyn(predicates) => {
@@ -1027,7 +1031,7 @@ impl TypeWalk for Ty {
                     p.walk_mut_binders(f, binders.shifted_in());
                 }
             }
-            Ty::Opaque(o_ty) => {
+            Ty::Alias(AliasTy::Opaque(o_ty)) => {
                 o_ty.parameters.walk_mut_binders(f, binders);
             }
             _ => {
diff --git a/crates/hir_ty/src/lower.rs b/crates/hir_ty/src/lower.rs
index 44bd95a9a..1b5843d48 100644
--- a/crates/hir_ty/src/lower.rs
+++ b/crates/hir_ty/src/lower.rs
@@ -8,6 +8,7 @@
 use std::{iter, sync::Arc};
 
 use base_db::CrateId;
+use chalk_ir::Mutability;
 use hir_def::{
     adt::StructKind,
     builtin_type::BuiltinType,
@@ -31,8 +32,8 @@ use crate::{
         all_super_trait_refs, associated_type_by_name_including_super_traits, generics,
         make_mut_slice, variant_data,
     },
-    Binders, BoundVar, CallableSig, DebruijnIndex, FnPointer, FnSig, GenericPredicate, OpaqueTy,
-    OpaqueTyId, PolyFnSig, ProjectionPredicate, ProjectionTy, ReturnTypeImplTrait,
+    AliasTy, Binders, BoundVar, CallableSig, DebruijnIndex, FnPointer, FnSig, GenericPredicate,
+    OpaqueTy, OpaqueTyId, PolyFnSig, ProjectionPredicate, ProjectionTy, ReturnTypeImplTrait,
     ReturnTypeImplTraits, Substs, TraitEnvironment, TraitRef, Ty, TypeWalk,
 };
 
@@ -157,7 +158,7 @@ impl Ty {
             }
             TypeRef::RawPtr(inner, mutability) => {
                 let inner_ty = Ty::from_hir(ctx, inner);
-                Ty::RawPtr(*mutability, Substs::single(inner_ty))
+                Ty::Raw(lower_to_chalk_mutability(*mutability), Substs::single(inner_ty))
             }
             TypeRef::Array(inner) => {
                 let inner_ty = Ty::from_hir(ctx, inner);
@@ -169,7 +170,7 @@ impl Ty {
             }
             TypeRef::Reference(inner, _, mutability) => {
                 let inner_ty = Ty::from_hir(ctx, inner);
-                Ty::Ref(*mutability, Substs::single(inner_ty))
+                Ty::Ref(lower_to_chalk_mutability(*mutability), Substs::single(inner_ty))
             }
             TypeRef::Placeholder => Ty::Unknown,
             TypeRef::Fn(params, is_varargs) => {
@@ -181,7 +182,7 @@ impl Ty {
                 })
             }
             TypeRef::DynTrait(bounds) => {
-                let self_ty = Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0));
+                let self_ty = Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0));
                 let predicates = ctx.with_shifted_in(DebruijnIndex::ONE, |ctx| {
                     bounds
                         .iter()
@@ -225,7 +226,10 @@ impl Ty {
                         let impl_trait_id = OpaqueTyId::ReturnTypeImplTrait(func, idx);
                         let generics = generics(ctx.db.upcast(), func.into());
                         let parameters = Substs::bound_vars(&generics, ctx.in_binders);
-                        Ty::Opaque(OpaqueTy { opaque_ty_id: impl_trait_id, parameters })
+                        Ty::Alias(AliasTy::Opaque(OpaqueTy {
+                            opaque_ty_id: impl_trait_id,
+                            parameters,
+                        }))
                     }
                     ImplTraitLoweringMode::Param => {
                         let idx = ctx.impl_trait_counter.get();
@@ -256,7 +260,7 @@ impl Ty {
                             } else {
                                 (0, 0, 0, 0)
                             };
-                        Ty::Bound(BoundVar::new(
+                        Ty::BoundVar(BoundVar::new(
                             ctx.in_binders,
                             idx as usize + parent_params + self_params + list_params,
                         ))
@@ -328,7 +332,7 @@ impl Ty {
             TypeNs::TraitId(trait_) => {
                 // if this is a bare dyn Trait, we'll directly put the required ^0 for the self type in there
                 let self_ty = if remaining_segments.len() == 0 {
-                    Some(Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0)))
+                    Some(Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0)))
                 } else {
                     None
                 };
@@ -344,10 +348,10 @@ impl Ty {
                     match found {
                         Some((super_trait_ref, associated_ty)) => {
                             // FIXME handle type parameters on the segment
-                            Ty::Projection(ProjectionTy {
+                            Ty::Alias(AliasTy::Projection(ProjectionTy {
                                 associated_ty,
                                 parameters: super_trait_ref.substs,
-                            })
+                            }))
                         }
                         None => {
                             // FIXME: report error (associated type not found)
@@ -371,7 +375,7 @@ impl Ty {
                     TypeParamLoweringMode::Placeholder => Ty::Placeholder(param_id),
                     TypeParamLoweringMode::Variable => {
                         let idx = generics.param_idx(param_id).expect("matching generics");
-                        Ty::Bound(BoundVar::new(ctx.in_binders, idx))
+                        Ty::BoundVar(BoundVar::new(ctx.in_binders, idx))
                     }
                 }
             }
@@ -469,10 +473,10 @@ impl Ty {
                         // associated_type_shorthand_candidates does not do that
                         let substs = substs.shift_bound_vars(ctx.in_binders);
                         // FIXME handle type parameters on the segment
-                        return Some(Ty::Projection(ProjectionTy {
+                        return Some(Ty::Alias(AliasTy::Projection(ProjectionTy {
                             associated_ty,
                             parameters: substs,
-                        }));
+                        })));
                     }
 
                     None
@@ -673,7 +677,7 @@ impl GenericPredicate {
                             TypeParamLoweringMode::Placeholder => Ty::Placeholder(param_id),
                             TypeParamLoweringMode::Variable => {
                                 let idx = generics.param_idx(param_id).expect("matching generics");
-                                Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, idx))
+                                Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, idx))
                             }
                         }
                     }
@@ -747,7 +751,7 @@ fn assoc_type_bindings_from_type_bound<'a>(
                 preds.extend(GenericPredicate::from_type_bound(
                     ctx,
                     bound,
-                    Ty::Projection(projection_ty.clone()),
+                    Ty::Alias(AliasTy::Projection(projection_ty.clone())),
                 ));
             }
             preds
@@ -757,7 +761,7 @@ fn assoc_type_bindings_from_type_bound<'a>(
 impl ReturnTypeImplTrait {
     fn from_hir(ctx: &TyLoweringContext, bounds: &[TypeBound]) -> Self {
         mark::hit!(lower_rpit);
-        let self_ty = Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, 0));
+        let self_ty = Ty::BoundVar(BoundVar::new(DebruijnIndex::INNERMOST, 0));
         let predicates = ctx.with_shifted_in(DebruijnIndex::ONE, |ctx| {
             bounds
                 .iter()
@@ -981,7 +985,7 @@ pub(crate) fn generic_defaults_query(
             // Each default can only refer to previous parameters.
             ty.walk_mut_binders(
                 &mut |ty, binders| match ty {
-                    Ty::Bound(BoundVar { debruijn, index }) if *debruijn == binders => {
+                    Ty::BoundVar(BoundVar { debruijn, index }) if *debruijn == binders => {
                         if *index >= idx {
                             // type variable default referring to parameter coming
                             // after it. This is forbidden (FIXME: report
@@ -1256,3 +1260,10 @@ pub(crate) fn return_type_impl_traits(
         Some(Arc::new(Binders::new(num_binders, return_type_impl_traits)))
     }
 }
+
+pub(crate) fn lower_to_chalk_mutability(m: hir_def::type_ref::Mutability) -> Mutability {
+    match m {
+        hir_def::type_ref::Mutability::Shared => Mutability::Not,
+        hir_def::type_ref::Mutability::Mut => Mutability::Mut,
+    }
+}
diff --git a/crates/hir_ty/src/method_resolution.rs b/crates/hir_ty/src/method_resolution.rs
index 8b1717873..f301a8477 100644
--- a/crates/hir_ty/src/method_resolution.rs
+++ b/crates/hir_ty/src/method_resolution.rs
@@ -6,9 +6,10 @@ use std::{iter, sync::Arc};
 
 use arrayvec::ArrayVec;
 use base_db::CrateId;
+use chalk_ir::Mutability;
 use hir_def::{
-    lang_item::LangItemTarget, type_ref::Mutability, AdtId, AssocContainerId, AssocItemId,
-    FunctionId, GenericDefId, HasModule, ImplId, Lookup, ModuleId, TraitId, TypeAliasId,
+    lang_item::LangItemTarget, AdtId, AssocContainerId, AssocItemId, FunctionId, GenericDefId,
+    HasModule, ImplId, Lookup, ModuleId, TraitId, TypeAliasId,
 };
 use hir_expand::name::Name;
 use rustc_hash::{FxHashMap, FxHashSet};
@@ -51,7 +52,7 @@ impl TyFingerprint {
             &Ty::Scalar(scalar) => TyFingerprint::Scalar(scalar),
             &Ty::Adt(adt, _) => TyFingerprint::Adt(adt),
             &Ty::Tuple(cardinality, _) => TyFingerprint::Tuple(cardinality),
-            &Ty::RawPtr(mutability, ..) => TyFingerprint::RawPtr(mutability),
+            &Ty::Raw(mutability, ..) => TyFingerprint::RawPtr(mutability),
             &Ty::ForeignType(alias_id, ..) => TyFingerprint::ForeignType(alias_id),
             &Ty::Function(FnPointer { num_args, sig, .. }) => TyFingerprint::FnPtr(num_args, sig),
             Ty::Dyn(_) => ty.dyn_trait().map(|trait_| TyFingerprint::Dyn(trait_))?,
@@ -251,8 +252,8 @@ impl Ty {
             }
             Ty::Str => lang_item_crate!("str_alloc", "str"),
             Ty::Slice(_) => lang_item_crate!("slice_alloc", "slice"),
-            Ty::RawPtr(Mutability::Shared, _) => lang_item_crate!("const_ptr"),
-            Ty::RawPtr(Mutability::Mut, _) => lang_item_crate!("mut_ptr"),
+            Ty::Raw(Mutability::Not, _) => lang_item_crate!("const_ptr"),
+            Ty::Raw(Mutability::Mut, _) => lang_item_crate!("mut_ptr"),
             Ty::Dyn(_) => {
                 return self.dyn_trait().and_then(|trait_| {
                     mod_to_crate_ids(GenericDefId::TraitId(trait_).module(db.upcast()))
@@ -429,7 +430,7 @@ fn iterate_method_candidates_with_autoref(
     }
     let refed = Canonical {
         kinds: deref_chain[0].kinds.clone(),
-        value: Ty::Ref(Mutability::Shared, Substs::single(deref_chain[0].value.clone())),
+        value: Ty::Ref(Mutability::Not, Substs::single(deref_chain[0].value.clone())),
     };
     if iterate_method_candidates_by_receiver(
         &refed,
@@ -683,7 +684,7 @@ pub(crate) fn inherent_impl_substs(
 fn fallback_bound_vars(s: Substs, num_vars_to_keep: usize) -> Substs {
     s.fold_binders(
         &mut |ty, binders| {
-            if let Ty::Bound(bound) = &ty {
+            if let Ty::BoundVar(bound) = &ty {
                 if bound.index >= num_vars_to_keep && bound.debruijn >= binders {
                     Ty::Unknown
                 } else {
diff --git a/crates/hir_ty/src/traits.rs b/crates/hir_ty/src/traits.rs
index dfa51896b..e4cdb6d53 100644
--- a/crates/hir_ty/src/traits.rs
+++ b/crates/hir_ty/src/traits.rs
@@ -129,7 +129,7 @@ pub(crate) fn trait_solve_query(
     log::info!("trait_solve_query({})", goal.value.value.display(db));
 
     if let Obligation::Projection(pred) = &goal.value.value {
-        if let Ty::Bound(_) = &pred.projection_ty.parameters[0] {
+        if let Ty::BoundVar(_) = &pred.projection_ty.parameters[0] {
             // Hack: don't ask Chalk to normalize with an unknown self type, it'll say that's impossible
             return Some(Solution::Ambig(Guidance::Unknown));
         }
diff --git a/crates/hir_ty/src/traits/chalk.rs b/crates/hir_ty/src/traits/chalk.rs
index 3f5f5091f..e513fa8f4 100644
--- a/crates/hir_ty/src/traits/chalk.rs
+++ b/crates/hir_ty/src/traits/chalk.rs
@@ -90,7 +90,7 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
             ty: &Ty,
             binders: &CanonicalVarKinds<Interner>,
         ) -> Option<chalk_ir::TyVariableKind> {
-            if let Ty::Bound(bv) = ty {
+            if let Ty::BoundVar(bv) = ty {
                 let binders = binders.as_slice(&Interner);
                 if bv.debruijn == DebruijnIndex::INNERMOST {
                     if let chalk_ir::VariableKind::Ty(tk) = binders[bv.index].kind {
@@ -220,18 +220,18 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
                     let impl_bound = GenericPredicate::Implemented(TraitRef {
                         trait_: future_trait,
                         // Self type as the first parameter.
-                        substs: Substs::single(Ty::Bound(BoundVar {
+                        substs: Substs::single(Ty::BoundVar(BoundVar {
                             debruijn: DebruijnIndex::INNERMOST,
                             index: 0,
                         })),
                     });
                     let proj_bound = GenericPredicate::Projection(ProjectionPredicate {
                         // The parameter of the opaque type.
-                        ty: Ty::Bound(BoundVar { debruijn: DebruijnIndex::ONE, index: 0 }),
+                        ty: Ty::BoundVar(BoundVar { debruijn: DebruijnIndex::ONE, index: 0 }),
                         projection_ty: ProjectionTy {
                             associated_ty: future_output,
                             // Self type as the first parameter.
-                            parameters: Substs::single(Ty::Bound(BoundVar::new(
+                            parameters: Substs::single(Ty::BoundVar(BoundVar::new(
                                 DebruijnIndex::INNERMOST,
                                 0,
                             ))),
@@ -392,7 +392,7 @@ pub(crate) fn associated_ty_data_query(
     let resolver = hir_def::resolver::HasResolver::resolver(type_alias, db.upcast());
     let ctx = crate::TyLoweringContext::new(db, &resolver)
         .with_type_param_mode(crate::lower::TypeParamLoweringMode::Variable);
-    let self_ty = Ty::Bound(crate::BoundVar::new(crate::DebruijnIndex::INNERMOST, 0));
+    let self_ty = Ty::BoundVar(crate::BoundVar::new(crate::DebruijnIndex::INNERMOST, 0));
     let bounds = type_alias_data
         .bounds
         .iter()
diff --git a/crates/hir_ty/src/traits/chalk/mapping.rs b/crates/hir_ty/src/traits/chalk/mapping.rs
index 995ff6a9a..db1760e6c 100644
--- a/crates/hir_ty/src/traits/chalk/mapping.rs
+++ b/crates/hir_ty/src/traits/chalk/mapping.rs
@@ -10,14 +10,14 @@ use chalk_ir::{
 use chalk_solve::rust_ir;
 
 use base_db::salsa::InternKey;
-use hir_def::{type_ref::Mutability, AssocContainerId, GenericDefId, Lookup, TypeAliasId};
+use hir_def::{AssocContainerId, GenericDefId, Lookup, TypeAliasId};
 
 use crate::{
     db::HirDatabase,
     primitive::UintTy,
     traits::{Canonical, Obligation},
-    CallableDefId, FnPointer, FnSig, GenericPredicate, InEnvironment, OpaqueTy, OpaqueTyId,
-    ProjectionPredicate, ProjectionTy, Scalar, Substs, TraitEnvironment, TraitRef, Ty,
+    AliasTy, CallableDefId, FnPointer, FnSig, GenericPredicate, InEnvironment, OpaqueTy,
+    OpaqueTyId, ProjectionPredicate, ProjectionTy, Scalar, Substs, TraitEnvironment, TraitRef, Ty,
 };
 
 use super::interner::*;
@@ -63,9 +63,9 @@ impl ToChalk for Ty {
                 let substitution = substs.to_chalk(db);
                 chalk_ir::TyKind::Tuple(cardinality.into(), substitution).intern(&Interner)
             }
-            Ty::RawPtr(mutability, substs) => {
+            Ty::Raw(mutability, substs) => {
                 let ty = substs[0].clone().to_chalk(db);
-                chalk_ir::TyKind::Raw(mutability.to_chalk(db), ty).intern(&Interner)
+                chalk_ir::TyKind::Raw(mutability, ty).intern(&Interner)
             }
             Ty::Slice(substs) => {
                 chalk_ir::TyKind::Slice(substs[0].clone().to_chalk(db)).intern(&Interner)
@@ -88,7 +88,7 @@ impl ToChalk for Ty {
                 let substitution = substs.to_chalk(db);
                 chalk_ir::TyKind::Adt(chalk_ir::AdtId(adt_id), substitution).intern(&Interner)
             }
-            Ty::Projection(proj_ty) => {
+            Ty::Alias(AliasTy::Projection(proj_ty)) => {
                 let associated_ty_id = TypeAliasAsAssocType(proj_ty.associated_ty).to_chalk(db);
                 let substitution = proj_ty.parameters.to_chalk(db);
                 chalk_ir::AliasTy::Projection(chalk_ir::ProjectionTy {
@@ -106,7 +106,7 @@ impl ToChalk for Ty {
                 }
                 .to_ty::<Interner>(&Interner)
             }
-            Ty::Bound(idx) => chalk_ir::TyKind::BoundVar(idx).intern(&Interner),
+            Ty::BoundVar(idx) => chalk_ir::TyKind::BoundVar(idx).intern(&Interner),
             Ty::InferenceVar(..) => panic!("uncanonicalized infer ty"),
             Ty::Dyn(predicates) => {
                 let where_clauses = chalk_ir::QuantifiedWhereClauses::from_iter(
@@ -119,7 +119,7 @@ impl ToChalk for Ty {
                 };
                 chalk_ir::TyKind::Dyn(bounded_ty).intern(&Interner)
             }
-            Ty::Opaque(opaque_ty) => {
+            Ty::Alias(AliasTy::Opaque(opaque_ty)) => {
                 let opaque_ty_id = opaque_ty.opaque_ty_id.to_chalk(db);
                 let substitution = opaque_ty.parameters.to_chalk(db);
                 chalk_ir::TyKind::Alias(chalk_ir::AliasTy::Opaque(chalk_ir::OpaqueTy {
@@ -146,12 +146,12 @@ impl ToChalk for Ty {
                 let associated_ty =
                     from_chalk::<TypeAliasAsAssocType, _>(db, proj.associated_ty_id).0;
                 let parameters = from_chalk(db, proj.substitution);
-                Ty::Projection(ProjectionTy { associated_ty, parameters })
+                Ty::Alias(AliasTy::Projection(ProjectionTy { associated_ty, parameters }))
             }
             chalk_ir::TyKind::Alias(chalk_ir::AliasTy::Opaque(opaque_ty)) => {
                 let impl_trait_id = from_chalk(db, opaque_ty.opaque_ty_id);
                 let parameters = from_chalk(db, opaque_ty.substitution);
-                Ty::Opaque(OpaqueTy { opaque_ty_id: impl_trait_id, parameters })
+                Ty::Alias(AliasTy::Opaque(OpaqueTy { opaque_ty_id: impl_trait_id, parameters }))
             }
             chalk_ir::TyKind::Function(chalk_ir::FnPointer {
                 num_binders,
@@ -170,7 +170,7 @@ impl ToChalk for Ty {
                     substs,
                 })
             }
-            chalk_ir::TyKind::BoundVar(idx) => Ty::Bound(idx),
+            chalk_ir::TyKind::BoundVar(idx) => Ty::BoundVar(idx),
             chalk_ir::TyKind::InferenceVar(_iv, _kind) => Ty::Unknown,
             chalk_ir::TyKind::Dyn(where_clauses) => {
                 assert_eq!(where_clauses.bounds.binders.len(&Interner), 1);
@@ -198,11 +198,11 @@ impl ToChalk for Ty {
                 Ty::Tuple(cardinality, from_chalk(db, subst))
             }
             chalk_ir::TyKind::Raw(mutability, ty) => {
-                Ty::RawPtr(from_chalk(db, mutability), Substs::single(from_chalk(db, ty)))
+                Ty::Raw(mutability, Substs::single(from_chalk(db, ty)))
             }
             chalk_ir::TyKind::Slice(ty) => Ty::Slice(Substs::single(from_chalk(db, ty))),
             chalk_ir::TyKind::Ref(mutability, _lifetime, ty) => {
-                Ty::Ref(from_chalk(db, mutability), Substs::single(from_chalk(db, ty)))
+                Ty::Ref(mutability, Substs::single(from_chalk(db, ty)))
             }
             chalk_ir::TyKind::Str => Ty::Str,
             chalk_ir::TyKind::Never => Ty::Never,
@@ -230,12 +230,12 @@ impl ToChalk for Ty {
 /// fake lifetime here, because Chalks built-in logic may expect it to be there.
 fn ref_to_chalk(
     db: &dyn HirDatabase,
-    mutability: Mutability,
+    mutability: chalk_ir::Mutability,
     subst: Substs,
 ) -> chalk_ir::Ty<Interner> {
     let arg = subst[0].clone().to_chalk(db);
     let lifetime = LifetimeData::Static.intern(&Interner);
-    chalk_ir::TyKind::Ref(mutability.to_chalk(db), lifetime, arg).intern(&Interner)
+    chalk_ir::TyKind::Ref(mutability, lifetime, arg).intern(&Interner)
 }
 
 /// We currently don't model constants, but Chalk does. So, we have to insert a
@@ -313,22 +313,6 @@ impl ToChalk for OpaqueTyId {
     }
 }
 
-impl ToChalk for Mutability {
-    type Chalk = chalk_ir::Mutability;
-    fn to_chalk(self, _db: &dyn HirDatabase) -> Self::Chalk {
-        match self {
-            Mutability::Shared => chalk_ir::Mutability::Not,
-            Mutability::Mut => chalk_ir::Mutability::Mut,
-        }
-    }
-    fn from_chalk(_db: &dyn HirDatabase, chalk: Self::Chalk) -> Self {
-        match chalk {
-            chalk_ir::Mutability::Mut => Mutability::Mut,
-            chalk_ir::Mutability::Not => Mutability::Shared,
-        }
-    }
-}
-
 impl ToChalk for hir_def::ImplId {
     type Chalk = ImplId;
 
diff --git a/crates/ide/src/hover.rs b/crates/ide/src/hover.rs
index 9a605b09d..20b799490 100644
--- a/crates/ide/src/hover.rs
+++ b/crates/ide/src/hover.rs
@@ -3496,4 +3496,33 @@ mod foo$0;
             "#]],
         );
     }
+
+    #[test]
+    fn hover_self_in_use() {
+        check(
+            r#"
+//! This should not appear
+mod foo {
+    /// But this should appear
+    pub mod bar {}
+}
+use foo::bar::{self$0};
+"#,
+            expect![[r#"
+                *self*
+
+                ```rust
+                test::foo
+                ```
+
+                ```rust
+                pub mod bar
+                ```
+
+                ---
+
+                But this should appear
+            "#]],
+        );
+    }
 }
diff --git a/crates/mbe/Cargo.toml b/crates/mbe/Cargo.toml
index bbee2e32c..8b5cca22c 100644
--- a/crates/mbe/Cargo.toml
+++ b/crates/mbe/Cargo.toml
@@ -19,8 +19,5 @@ parser = { path = "../parser", version = "0.0.0" }
 tt = { path = "../tt", version = "0.0.0" }
 test_utils = { path = "../test_utils", version = "0.0.0" }
 
-# FIXME: Paper over a bug in cargo-worspaces which block publishing
-# https://github.com/pksunkara/cargo-workspaces/issues/39
-# [dev-dependencies]
-profile = { path = "../profile", version = "0.0.0" }
-
+[dev-dependencies]
+profile = { path = "../profile" }