Merge #1352

1352: Builtins r=matklad a=matklad

closes #1340

Co-authored-by: Aleksey Kladov <[email protected]>

21 files changed, 261 insertions, 118 deletions

diff --git a/Cargo.lock b/Cargo.lock
index b56586ac1..e38fa0ff0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1084,6 +1084,7 @@ dependencies = [
  "insta 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "join_to_string 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "once_cell 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "parking_lot 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_arena 0.1.0",
  "ra_db 0.1.0",
diff --git a/crates/ra_hir/Cargo.toml b/crates/ra_hir/Cargo.toml
index a86dfa6b2..78808e72f 100644
--- a/crates/ra_hir/Cargo.toml
+++ b/crates/ra_hir/Cargo.toml
@@ -13,6 +13,7 @@ parking_lot = "0.8.0"
 ena = "0.11"
 join_to_string = "0.1.3"
 either = "1.5.2"
+once_cell = "0.2"
 
 ra_syntax = { path = "../ra_syntax" }
 ra_arena = { path = "../ra_arena" }
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index 69496b624..e3c765674 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -4,12 +4,12 @@ use ra_db::{CrateId, SourceRootId, Edition, FileId};
 use ra_syntax::{ast::{self, NameOwner, TypeAscriptionOwner}, TreeArc};
 
 use crate::{
-    Name, AsName, AstId, Ty, HirFileId, Either,
+    Name, AsName, AstId, Ty, HirFileId, Either, KnownName,
     HirDatabase, DefDatabase,
     type_ref::TypeRef,
     nameres::{ModuleScope, Namespace, ImportId, CrateModuleId},
     expr::{Body, BodySourceMap, validation::ExprValidator},
-    ty::{TraitRef, InferenceResult},
+    ty::{TraitRef, InferenceResult, primitive::{IntTy, FloatTy, Signedness, IntBitness, FloatBitness}},
     adt::{EnumVariantId, StructFieldId, VariantDef},
     generics::HasGenericParams,
     docs::{Documentation, Docs, docs_from_ast},
@@ -75,6 +75,41 @@ pub struct Module {
     pub(crate) module_id: CrateModuleId,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub enum BuiltinType {
+    Char,
+    Bool,
+    Str,
+    Int(IntTy),
+    Float(FloatTy),
+}
+
+impl BuiltinType {
+    #[rustfmt::skip]
+    pub(crate) const ALL: &'static [(KnownName, BuiltinType)] = &[
+        (KnownName::Char, BuiltinType::Char),
+        (KnownName::Bool, BuiltinType::Bool),
+        (KnownName::Str, BuiltinType::Str),
+
+        (KnownName::Isize, BuiltinType::Int(IntTy { signedness: Signedness::Signed, bitness: IntBitness::Xsize })),
+        (KnownName::I8,    BuiltinType::Int(IntTy { signedness: Signedness::Signed, bitness: IntBitness::X8 })),
+        (KnownName::I16,   BuiltinType::Int(IntTy { signedness: Signedness::Signed, bitness: IntBitness::X16 })),
+        (KnownName::I32,   BuiltinType::Int(IntTy { signedness: Signedness::Signed, bitness: IntBitness::X32 })),
+        (KnownName::I64,   BuiltinType::Int(IntTy { signedness: Signedness::Signed, bitness: IntBitness::X64 })),
+        (KnownName::I128,  BuiltinType::Int(IntTy { signedness: Signedness::Signed, bitness: IntBitness::X128 })),
+
+        (KnownName::Usize, BuiltinType::Int(IntTy { signedness: Signedness::Unsigned, bitness: IntBitness::Xsize })),
+        (KnownName::U8,    BuiltinType::Int(IntTy { signedness: Signedness::Unsigned, bitness: IntBitness::X8 })),
+        (KnownName::U16,   BuiltinType::Int(IntTy { signedness: Signedness::Unsigned, bitness: IntBitness::X16 })),
+        (KnownName::U32,   BuiltinType::Int(IntTy { signedness: Signedness::Unsigned, bitness: IntBitness::X32 })),
+        (KnownName::U64,   BuiltinType::Int(IntTy { signedness: Signedness::Unsigned, bitness: IntBitness::X64 })),
+        (KnownName::U128,  BuiltinType::Int(IntTy { signedness: Signedness::Unsigned, bitness: IntBitness::X128 })),
+
+        (KnownName::F32, BuiltinType::Float(FloatTy { bitness: FloatBitness::X32 })),
+        (KnownName::F64, BuiltinType::Float(FloatTy { bitness: FloatBitness::X64 })),
+    ];
+}
+
 /// The defs which can be visible in the module.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum ModuleDef {
@@ -89,6 +124,7 @@ pub enum ModuleDef {
     Static(Static),
     Trait(Trait),
     TypeAlias(TypeAlias),
+    BuiltinType(BuiltinType),
 }
 impl_froms!(
     ModuleDef: Module,
@@ -100,7 +136,8 @@ impl_froms!(
     Const,
     Static,
     Trait,
-    TypeAlias
+    TypeAlias,
+    BuiltinType
 );
 
 pub enum ModuleSource {
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index cb09c60f8..3e00eea26 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -6,7 +6,7 @@
 //! applied. So, the relation between syntax and HIR is many-to-one.
 
 macro_rules! impl_froms {
-    ($e:ident: $($v:ident), *) => {
+    ($e:ident: $($v:ident),*) => {
         $(
             impl From<$v> for $e {
                 fn from(it: $v) -> $e {
@@ -80,5 +80,6 @@ pub use self::code_model::{
     Function, FnSignature,
     StructField, FieldSource,
     Static, Const, ConstSignature,
-    Trait, TypeAlias, MacroDef, Container
+    Trait, TypeAlias, MacroDef, Container,
+    BuiltinType,
 };
diff --git a/crates/ra_hir/src/name.rs b/crates/ra_hir/src/name.rs
index e3a82cf03..e9003e00b 100644
--- a/crates/ra_hir/src/name.rs
+++ b/crates/ra_hir/src/name.rs
@@ -123,7 +123,7 @@ impl AsName for ra_db::Dependency {
 // const ISIZE: Name = Name::new("isize")
 // ```
 // but const-fn is not that powerful yet.
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub(crate) enum KnownName {
     Isize,
     I8,
@@ -151,3 +151,31 @@ pub(crate) enum KnownName {
 
     MacroRules,
 }
+
+impl AsName for KnownName {
+    fn as_name(&self) -> Name {
+        let s = match self {
+            KnownName::Isize => "isize",
+            KnownName::I8 => "i8",
+            KnownName::I16 => "i16",
+            KnownName::I32 => "i32",
+            KnownName::I64 => "i64",
+            KnownName::I128 => "i128",
+            KnownName::Usize => "usize",
+            KnownName::U8 => "u8",
+            KnownName::U16 => "u16",
+            KnownName::U32 => "u32",
+            KnownName::U64 => "u64",
+            KnownName::U128 => "u128",
+            KnownName::F32 => "f32",
+            KnownName::F64 => "f64",
+            KnownName::Bool => "bool",
+            KnownName::Char => "char",
+            KnownName::Str => "str",
+            KnownName::SelfType => "Self",
+            KnownName::SelfParam => "self",
+            KnownName::MacroRules => "macro_rules",
+        };
+        Name::new(s.into())
+    }
+}
diff --git a/crates/ra_hir/src/nameres.rs b/crates/ra_hir/src/nameres.rs
index 42dcac332..aa26345b2 100644
--- a/crates/ra_hir/src/nameres.rs
+++ b/crates/ra_hir/src/nameres.rs
@@ -62,9 +62,10 @@ use ra_db::{FileId, Edition};
 use test_utils::tested_by;
 use ra_syntax::ast;
 use ra_prof::profile;
+use once_cell::sync::Lazy;
 
 use crate::{
-    ModuleDef, Name, Crate, Module, MacroDef,
+    ModuleDef, Name, Crate, Module, MacroDef, AsName, BuiltinType,
     DefDatabase, Path, PathKind, HirFileId, Trait,
     ids::MacroDefId,
     diagnostics::DiagnosticSink,
@@ -140,12 +141,22 @@ pub struct ModuleScope {
     macros: FxHashMap<Name, MacroDef>,
 }
 
+static BUILTIN_SCOPE: Lazy<FxHashMap<Name, Resolution>> = Lazy::new(|| {
+    BuiltinType::ALL
+        .iter()
+        .map(|&(known_name, ty)| {
+            (known_name.as_name(), Resolution { def: PerNs::types(ty.into()), import: None })
+        })
+        .collect()
+});
+
 impl ModuleScope {
     pub fn entries<'a>(&'a self) -> impl Iterator<Item = (&'a Name, &'a Resolution)> + 'a {
-        self.items.iter()
+        //FIXME: shadowing
+        self.items.iter().chain(BUILTIN_SCOPE.iter())
     }
     pub fn get(&self, name: &Name) -> Option<&Resolution> {
-        self.items.get(name)
+        self.items.get(name).or_else(|| BUILTIN_SCOPE.get(name))
     }
     pub fn traits<'a>(&'a self) -> impl Iterator<Item = Trait> + 'a {
         self.items.values().filter_map(|r| match r.def.take_types() {
@@ -154,7 +165,7 @@ impl ModuleScope {
         })
     }
     fn get_item_or_macro(&self, name: &Name) -> Option<ItemOrMacro> {
-        match (self.items.get(name), self.macros.get(name)) {
+        match (self.get(name), self.macros.get(name)) {
             (Some(item), _) if !item.def.is_none() => Some(Either::Left(item.def)),
             (_, Some(macro_)) => Some(Either::Right(*macro_)),
             _ => None,
diff --git a/crates/ra_hir/src/nameres/tests.rs b/crates/ra_hir/src/nameres/tests.rs
index ffb627c02..a15e62bbe 100644
--- a/crates/ra_hir/src/nameres/tests.rs
+++ b/crates/ra_hir/src/nameres/tests.rs
@@ -1,6 +1,7 @@
 mod macros;
 mod globs;
 mod incremental;
+mod primitives;
 
 use std::sync::Arc;
 
diff --git a/crates/ra_hir/src/nameres/tests/incremental.rs b/crates/ra_hir/src/nameres/tests/incremental.rs
index 001f76ac3..bc721f6e0 100644
--- a/crates/ra_hir/src/nameres/tests/incremental.rs
+++ b/crates/ra_hir/src/nameres/tests/incremental.rs
@@ -116,7 +116,7 @@ fn typing_inside_a_macro_should_not_invalidate_def_map() {
         let events = db.log_executed(|| {
             let module = crate::source_binder::module_from_file_id(&db, pos.file_id).unwrap();
             let decls = module.declarations(&db);
-            assert_eq!(decls.len(), 1);
+            assert_eq!(decls.len(), 18);
         });
         assert!(format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
     }
@@ -126,7 +126,7 @@ fn typing_inside_a_macro_should_not_invalidate_def_map() {
         let events = db.log_executed(|| {
             let module = crate::source_binder::module_from_file_id(&db, pos.file_id).unwrap();
             let decls = module.declarations(&db);
-            assert_eq!(decls.len(), 1);
+            assert_eq!(decls.len(), 18);
         });
         assert!(!format!("{:?}", events).contains("crate_def_map"), "{:#?}", events)
     }
diff --git a/crates/ra_hir/src/nameres/tests/primitives.rs b/crates/ra_hir/src/nameres/tests/primitives.rs
new file mode 100644
index 000000000..734744835
--- /dev/null
+++ b/crates/ra_hir/src/nameres/tests/primitives.rs
@@ -0,0 +1,24 @@
+use super::*;
+
+#[test]
+fn primitive_reexport() {
+    let map = def_map(
+        "
+        //- /lib.rs
+        mod foo;
+        use foo::int;
+
+        //- /foo.rs
+        pub use i32 as int;
+        ",
+    );
+    assert_snapshot_matches!(map, @r###"
+   ⋮crate
+   ⋮foo: t
+   ⋮int: t
+   ⋮
+   ⋮crate::foo
+   ⋮int: t
+    "###
+    );
+}
diff --git a/crates/ra_hir/src/ty/infer.rs b/crates/ra_hir/src/ty/infer.rs
index 7d8250292..e8ae33ead 100644
--- a/crates/ra_hir/src/ty/infer.rs
+++ b/crates/ra_hir/src/ty/infer.rs
@@ -649,7 +649,8 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
             | TypableDef::Function(_)
             | TypableDef::Enum(_)
             | TypableDef::Const(_)
-            | TypableDef::Static(_) => (Ty::Unknown, None),
+            | TypableDef::Static(_)
+            | TypableDef::BuiltinType(_) => (Ty::Unknown, None),
         }
     }
 
diff --git a/crates/ra_hir/src/ty/lower.rs b/crates/ra_hir/src/ty/lower.rs
index 7defa7a9b..71cd72234 100644
--- a/crates/ra_hir/src/ty/lower.rs
+++ b/crates/ra_hir/src/ty/lower.rs
@@ -10,9 +10,8 @@ use std::iter;
 
 use crate::{
     Function, Struct, Union, StructField, Enum, EnumVariant, Path, ModuleDef, TypeAlias, Const, Static,
-    HirDatabase,
+    HirDatabase, BuiltinType,
     type_ref::TypeRef,
-    name::KnownName,
     nameres::Namespace,
     resolve::{Resolver, Resolution},
     path::{PathSegment, GenericArg},
@@ -22,7 +21,7 @@ use crate::{
     generics::{WherePredicate, GenericDef},
     ty::AdtDef,
 };
-use super::{Ty, primitive, FnSig, Substs, TypeCtor, TraitRef, GenericPredicate};
+use super::{Ty, FnSig, Substs, TypeCtor, TraitRef, GenericPredicate};
 
 impl Ty {
     pub(crate) fn from_hir(db: &impl HirDatabase, resolver: &Resolver, type_ref: &TypeRef) -> Self {
@@ -65,22 +64,6 @@ impl Ty {
     }
 
     pub(crate) fn from_hir_path(db: &impl HirDatabase, resolver: &Resolver, path: &Path) -> Self {
-        if let Some(name) = path.as_ident() {
-            // FIXME handle primitive type names in resolver as well?
-            if let Some(int_ty) = primitive::IntTy::from_type_name(name) {
-                return Ty::simple(TypeCtor::Int(primitive::UncertainIntTy::Known(int_ty)));
-            } else if let Some(float_ty) = primitive::FloatTy::from_type_name(name) {
-                return Ty::simple(TypeCtor::Float(primitive::UncertainFloatTy::Known(float_ty)));
-            } else if let Some(known) = name.as_known_name() {
-                match known {
-                    KnownName::Bool => return Ty::simple(TypeCtor::Bool),
-                    KnownName::Char => return Ty::simple(TypeCtor::Char),
-                    KnownName::Str => return Ty::simple(TypeCtor::Str),
-                    _ => {}
-                }
-            }
-        }
-
         // Resolve the path (in type namespace)
         let resolution = resolver.resolve_path(db, path).take_types();
 
@@ -128,7 +111,7 @@ impl Ty {
             TypableDef::Enum(e) => Some(e.into()),
             TypableDef::EnumVariant(var) => Some(var.parent_enum(db).into()),
             TypableDef::TypeAlias(t) => Some(t.into()),
-            TypableDef::Const(_) | TypableDef::Static(_) => None,
+            TypableDef::Const(_) | TypableDef::Static(_) | TypableDef::BuiltinType(_) => None,
         };
         substs_from_path_segment(db, resolver, segment, def_generic, false)
     }
@@ -149,7 +132,8 @@ impl Ty {
             | TypableDef::Enum(_)
             | TypableDef::Const(_)
             | TypableDef::Static(_)
-            | TypableDef::TypeAlias(_) => last,
+            | TypableDef::TypeAlias(_)
+            | TypableDef::BuiltinType(_) => last,
             TypableDef::EnumVariant(_) => {
                 // the generic args for an enum variant may be either specified
                 // on the segment referring to the enum, or on the segment
@@ -299,6 +283,7 @@ pub(crate) fn type_for_def(db: &impl HirDatabase, def: TypableDef, ns: Namespace
         (TypableDef::TypeAlias(t), Namespace::Types) => type_for_type_alias(db, t),
         (TypableDef::Const(c), Namespace::Values) => type_for_const(db, c),
         (TypableDef::Static(c), Namespace::Values) => type_for_static(db, c),
+        (TypableDef::BuiltinType(t), Namespace::Types) => type_for_builtin(t),
 
         // 'error' cases:
         (TypableDef::Function(_), Namespace::Types) => Ty::Unknown,
@@ -308,6 +293,7 @@ pub(crate) fn type_for_def(db: &impl HirDatabase, def: TypableDef, ns: Namespace
         (TypableDef::TypeAlias(_), Namespace::Values) => Ty::Unknown,
         (TypableDef::Const(_), Namespace::Types) => Ty::Unknown,
         (TypableDef::Static(_), Namespace::Types) => Ty::Unknown,
+        (TypableDef::BuiltinType(_), Namespace::Values) => Ty::Unknown,
     }
 }
 
@@ -399,6 +385,17 @@ fn type_for_static(db: &impl HirDatabase, def: Static) -> Ty {
     Ty::from_hir(db, &resolver, signature.type_ref())
 }
 
+/// Build the declared type of a static.
+fn type_for_builtin(def: BuiltinType) -> Ty {
+    Ty::simple(match def {
+        BuiltinType::Char => TypeCtor::Char,
+        BuiltinType::Bool => TypeCtor::Bool,
+        BuiltinType::Str => TypeCtor::Str,
+        BuiltinType::Int(ty) => TypeCtor::Int(ty.into()),
+        BuiltinType::Float(ty) => TypeCtor::Float(ty.into()),
+    })
+}
+
 fn fn_sig_for_struct_constructor(db: &impl HirDatabase, def: Struct) -> FnSig {
     let var_data = def.variant_data(db);
     let fields = match var_data.fields() {
@@ -477,8 +474,19 @@ pub enum TypableDef {
     TypeAlias(TypeAlias),
     Const(Const),
     Static(Static),
+    BuiltinType(BuiltinType),
 }
-impl_froms!(TypableDef: Function, Struct, Union, Enum, EnumVariant, TypeAlias, Const, Static);
+impl_froms!(
+    TypableDef: Function,
+    Struct,
+    Union,
+    Enum,
+    EnumVariant,
+    TypeAlias,
+    Const,
+    Static,
+    BuiltinType
+);
 
 impl From<ModuleDef> for Option<TypableDef> {
     fn from(def: ModuleDef) -> Option<TypableDef> {
@@ -491,6 +499,7 @@ impl From<ModuleDef> for Option<TypableDef> {
             ModuleDef::TypeAlias(t) => t.into(),
             ModuleDef::Const(v) => v.into(),
             ModuleDef::Static(v) => v.into(),
+            ModuleDef::BuiltinType(t) => t.into(),
             ModuleDef::Module(_) | ModuleDef::Trait(_) => return None,
         };
         Some(res)
diff --git a/crates/ra_hir/src/ty/primitive.rs b/crates/ra_hir/src/ty/primitive.rs
index b37326db7..62b75b764 100644
--- a/crates/ra_hir/src/ty/primitive.rs
+++ b/crates/ra_hir/src/ty/primitive.rs
@@ -1,7 +1,5 @@
 use std::fmt;
 
-use crate::{Name, KnownName};
-
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
 pub enum Signedness {
     Signed,
@@ -30,6 +28,12 @@ pub enum UncertainIntTy {
     Known(IntTy),
 }
 
+impl From<IntTy> for UncertainIntTy {
+    fn from(ty: IntTy) -> Self {
+        UncertainIntTy::Known(ty)
+    }
+}
+
 impl fmt::Display for UncertainIntTy {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match *self {
@@ -45,6 +49,12 @@ pub enum UncertainFloatTy {
     Known(FloatTy),
 }
 
+impl From<FloatTy> for UncertainFloatTy {
+    fn from(ty: FloatTy) -> Self {
+        UncertainFloatTy::Known(ty)
+    }
+}
+
 impl fmt::Display for UncertainFloatTy {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         match *self {
@@ -138,24 +148,6 @@ impl IntTy {
         }
     }
 
-    pub(crate) fn from_type_name(name: &Name) -> Option<IntTy> {
-        match name.as_known_name()? {
-            KnownName::Isize => Some(IntTy::isize()),
-            KnownName::I8 => Some(IntTy::i8()),
-            KnownName::I16 => Some(IntTy::i16()),
-            KnownName::I32 => Some(IntTy::i32()),
-            KnownName::I64 => Some(IntTy::i64()),
-            KnownName::I128 => Some(IntTy::i128()),
-            KnownName::Usize => Some(IntTy::usize()),
-            KnownName::U8 => Some(IntTy::u8()),
-            KnownName::U16 => Some(IntTy::u16()),
-            KnownName::U32 => Some(IntTy::u32()),
-            KnownName::U64 => Some(IntTy::u64()),
-            KnownName::U128 => Some(IntTy::u128()),
-            _ => None,
-        }
-    }
-
     pub(crate) fn from_suffix(suffix: &str) -> Option<IntTy> {
         match suffix {
             "isize" => Some(IntTy::isize()),
@@ -208,14 +200,6 @@ impl FloatTy {
         }
     }
 
-    pub(crate) fn from_type_name(name: &Name) -> Option<FloatTy> {
-        match name.as_known_name()? {
-            KnownName::F32 => Some(FloatTy::f32()),
-            KnownName::F64 => Some(FloatTy::f64()),
-            _ => None,
-        }
-    }
-
     pub(crate) fn from_suffix(suffix: &str) -> Option<FloatTy> {
         match suffix {
             "f32" => Some(FloatTy::f32()),
diff --git a/crates/ra_hir/src/ty/tests.rs b/crates/ra_hir/src/ty/tests.rs
index da9aeec6d..c34e89af7 100644
--- a/crates/ra_hir/src/ty/tests.rs
+++ b/crates/ra_hir/src/ty/tests.rs
@@ -2717,6 +2717,24 @@ fn test() { (S {}).method()<|>; }
     assert_eq!(t, "{unknown}");
 }
 
+#[test]
+fn shadowing_primitive() {
+    let t = type_at(
+        r#"
+//- /main.rs
+struct i32;
+struct Foo;
+
+impl i32 { fn foo(&self) -> Foo { Foo } }
+
+fn main() {
+    let x: i32 = i32;
+    x.foo()<|>;
+}"#,
+    );
+    assert_eq!(t, "Foo");
+}
+
 fn type_at_pos(db: &MockDatabase, pos: FilePosition) -> String {
     let file = db.parse(pos.file_id).ok().unwrap();
     let expr = algo::find_node_at_offset::<ast::Expr>(file.syntax(), pos.offset).unwrap();
diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index c41752ae7..99da24142 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -17,6 +17,12 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
         hir::ModuleDef::Module(module) => {
             let module_scope = module.scope(ctx.db);
             for (name, res) in module_scope.entries() {
+                if let Some(hir::ModuleDef::BuiltinType(..)) = res.def.as_ref().take_types() {
+                    if ctx.use_item_syntax.is_some() {
+                        tested_by!(dont_complete_primitive_in_use);
+                        continue;
+                    }
+                }
                 if Some(module) == ctx.module {
                     if let Some(import) = res.import {
                         if let Either::A(use_tree) = module.import_source(ctx.db, import) {
@@ -89,6 +95,20 @@ mod tests {
     }
 
     #[test]
+    fn dont_complete_primitive_in_use() {
+        covers!(dont_complete_primitive_in_use);
+        let completions = do_completion(r"use self::<|>;", CompletionKind::BuiltinType);
+        assert!(completions.is_empty());
+    }
+
+    #[test]
+    fn completes_primitives() {
+        let completions =
+            do_completion(r"fn main() { let _: <|> = 92; }", CompletionKind::BuiltinType);
+        assert_eq!(completions.len(), 17);
+    }
+
+    #[test]
     fn completes_mod_with_docs() {
         check_reference_completion(
             "mod_with_docs",
diff --git a/crates/ra_ide_api/src/completion/completion_item.rs b/crates/ra_ide_api/src/completion/completion_item.rs
index 6f1392231..6f2a60640 100644
--- a/crates/ra_ide_api/src/completion/completion_item.rs
+++ b/crates/ra_ide_api/src/completion/completion_item.rs
@@ -78,6 +78,7 @@ pub enum CompletionItemKind {
     Keyword,
     Module,
     Function,
+    BuiltinType,
     Struct,
     Enum,
     EnumVariant,
@@ -102,6 +103,7 @@ pub(crate) enum CompletionKind {
     Magic,
     Snippet,
     Postfix,
+    BuiltinType,
 }
 
 #[derive(Debug, PartialEq, Eq, Copy, Clone)]
diff --git a/crates/ra_ide_api/src/completion/presentation.rs b/crates/ra_ide_api/src/completion/presentation.rs
index 064d379a4..d405161d6 100644
--- a/crates/ra_ide_api/src/completion/presentation.rs
+++ b/crates/ra_ide_api/src/completion/presentation.rs
@@ -57,6 +57,7 @@ impl Completions {
             }
             Some(it) => it,
         };
+        let mut completion_kind = CompletionKind::Reference;
         let (kind, docs) = match def {
             Resolution::Def(Module(it)) => (CompletionItemKind::Module, it.docs(ctx.db)),
             Resolution::Def(Function(func)) => {
@@ -70,6 +71,10 @@ impl Completions {
             Resolution::Def(Static(it)) => (CompletionItemKind::Static, it.docs(ctx.db)),
             Resolution::Def(Trait(it)) => (CompletionItemKind::Trait, it.docs(ctx.db)),
             Resolution::Def(TypeAlias(it)) => (CompletionItemKind::TypeAlias, it.docs(ctx.db)),
+            Resolution::Def(BuiltinType(..)) => {
+                completion_kind = CompletionKind::BuiltinType;
+                (CompletionItemKind::BuiltinType, None)
+            }
             Resolution::GenericParam(..) => (CompletionItemKind::TypeParam, None),
             Resolution::LocalBinding(..) => (CompletionItemKind::Binding, None),
             Resolution::SelfType(..) => (
@@ -77,7 +82,7 @@ impl Completions {
                 None,
             ),
         };
-        CompletionItem::new(CompletionKind::Reference, ctx.source_range(), local_name)
+        CompletionItem::new(completion_kind, ctx.source_range(), local_name)
             .kind(kind)
             .set_documentation(docs)
             .add_to(self)
diff --git a/crates/ra_ide_api/src/display/navigation_target.rs b/crates/ra_ide_api/src/display/navigation_target.rs
index ae729614f..e19c071b0 100644
--- a/crates/ra_ide_api/src/display/navigation_target.rs
+++ b/crates/ra_ide_api/src/display/navigation_target.rs
@@ -165,8 +165,11 @@ impl NavigationTarget {
         }
     }
 
-    pub(crate) fn from_def(db: &RootDatabase, module_def: hir::ModuleDef) -> NavigationTarget {
-        match module_def {
+    pub(crate) fn from_def(
+        db: &RootDatabase,
+        module_def: hir::ModuleDef,
+    ) -> Option<NavigationTarget> {
+        let nav = match module_def {
             hir::ModuleDef::Module(module) => NavigationTarget::from_module(db, module),
             hir::ModuleDef::Function(func) => NavigationTarget::from_function(db, func),
             hir::ModuleDef::Struct(s) => {
@@ -201,7 +204,11 @@ impl NavigationTarget {
                 let (file_id, node) = e.source(db);
                 NavigationTarget::from_named(file_id.original_file(db), &*node)
             }
-        }
+            hir::ModuleDef::BuiltinType(..) => {
+                return None;
+            }
+        };
+        Some(nav)
     }
 
     pub(crate) fn from_impl_block(
diff --git a/crates/ra_ide_api/src/goto_definition.rs b/crates/ra_ide_api/src/goto_definition.rs
index 4f8554625..97b367115 100644
--- a/crates/ra_ide_api/src/goto_definition.rs
+++ b/crates/ra_ide_api/src/goto_definition.rs
@@ -62,7 +62,10 @@ pub(crate) fn reference_definition(
         Some(Macro(mac)) => return Exact(NavigationTarget::from_macro_def(db, mac)),
         Some(FieldAccess(field)) => return Exact(NavigationTarget::from_field(db, field)),
         Some(AssocItem(assoc)) => return Exact(NavigationTarget::from_impl_item(db, assoc)),
-        Some(Def(def)) => return Exact(NavigationTarget::from_def(db, def)),
+        Some(Def(def)) => match NavigationTarget::from_def(db, def) {
+            Some(nav) => return Exact(nav),
+            None => return Approximate(vec![]),
+        },
         Some(SelfType(ty)) => {
             if let Some((def_id, _)) = ty.as_adt() {
                 return Exact(NavigationTarget::from_adt_def(db, def_id));
diff --git a/crates/ra_ide_api/src/marks.rs b/crates/ra_ide_api/src/marks.rs
index cc894a7df..9cb991de5 100644
--- a/crates/ra_ide_api/src/marks.rs
+++ b/crates/ra_ide_api/src/marks.rs
@@ -6,4 +6,5 @@ test_utils::marks!(
     goto_definition_works_for_named_fields
     call_info_bad_offset
     dont_complete_current_use
+    dont_complete_primitive_in_use
 );
diff --git a/crates/ra_ide_api/src/syntax_highlighting.rs b/crates/ra_ide_api/src/syntax_highlighting.rs
index 4b24754a8..3a04a51cd 100644
--- a/crates/ra_ide_api/src/syntax_highlighting.rs
+++ b/crates/ra_ide_api/src/syntax_highlighting.rs
@@ -30,14 +30,6 @@ fn is_control_keyword(kind: SyntaxKind) -> bool {
     }
 }
 
-fn is_prim_type(node: &ast::NameRef) -> bool {
-    match node.text().as_str() {
-        "u8" | "i8" | "u16" | "i16" | "u32" | "i32" | "u64" | "i64" | "u128" | "i128" | "usize"
-        | "isize" | "f32" | "f64" | "bool" | "char" | "str" => true,
-        _ => false,
-    }
-}
-
 pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Vec<HighlightedRange> {
     let _p = profile("highlight");
     let source_file = db.parse(file_id).tree;
@@ -71,51 +63,47 @@ pub(crate) fn highlight(db: &RootDatabase, file_id: FileId) -> Vec<HighlightedRa
             NAME_REF => {
                 if let Some(name_ref) = node.as_node().and_then(ast::NameRef::cast) {
                     // FIXME: revisit this after #1340
-                    if is_prim_type(name_ref) {
-                        "type"
-                    } else {
-                        use crate::name_ref_kind::{classify_name_ref, NameRefKind::*};
-                        use hir::{ModuleDef, ImplItem};
+                    use crate::name_ref_kind::{classify_name_ref, NameRefKind::*};
+                    use hir::{ModuleDef, ImplItem};
 
-                        // FIXME: try to reuse the SourceAnalyzers
-                        let analyzer =
-                            hir::SourceAnalyzer::new(db, file_id, name_ref.syntax(), None);
-                        match classify_name_ref(db, &analyzer, name_ref) {
-                            Some(Method(_)) => "function",
-                            Some(Macro(_)) => "macro",
-                            Some(FieldAccess(_)) => "field",
-                            Some(AssocItem(ImplItem::Method(_))) => "function",
-                            Some(AssocItem(ImplItem::Const(_))) => "constant",
-                            Some(AssocItem(ImplItem::TypeAlias(_))) => "type",
-                            Some(Def(ModuleDef::Module(_))) => "module",
-                            Some(Def(ModuleDef::Function(_))) => "function",
-                            Some(Def(ModuleDef::Struct(_))) => "type",
-                            Some(Def(ModuleDef::Union(_))) => "type",
-                            Some(Def(ModuleDef::Enum(_))) => "type",
-                            Some(Def(ModuleDef::EnumVariant(_))) => "constant",
-                            Some(Def(ModuleDef::Const(_))) => "constant",
-                            Some(Def(ModuleDef::Static(_))) => "constant",
-                            Some(Def(ModuleDef::Trait(_))) => "type",
-                            Some(Def(ModuleDef::TypeAlias(_))) => "type",
-                            Some(SelfType(_)) => "type",
-                            Some(Pat(ptr)) => {
-                                binding_hash = Some({
-                                    let text = ptr
-                                        .syntax_node_ptr()
-                                        .to_node(&source_file.syntax())
-                                        .text()
-                                        .to_smol_string();
-                                    let shadow_count =
-                                        bindings_shadow_count.entry(text.clone()).or_default();
-                                    calc_binding_hash(file_id, &text, *shadow_count)
-                                });
+                    // FIXME: try to reuse the SourceAnalyzers
+                    let analyzer = hir::SourceAnalyzer::new(db, file_id, name_ref.syntax(), None);
+                    match classify_name_ref(db, &analyzer, name_ref) {
+                        Some(Method(_)) => "function",
+                        Some(Macro(_)) => "macro",
+                        Some(FieldAccess(_)) => "field",
+                        Some(AssocItem(ImplItem::Method(_))) => "function",
+                        Some(AssocItem(ImplItem::Const(_))) => "constant",
+                        Some(AssocItem(ImplItem::TypeAlias(_))) => "type",
+                        Some(Def(ModuleDef::Module(_))) => "module",
+                        Some(Def(ModuleDef::Function(_))) => "function",
+                        Some(Def(ModuleDef::Struct(_))) => "type",
+                        Some(Def(ModuleDef::Union(_))) => "type",
+                        Some(Def(ModuleDef::Enum(_))) => "type",
+                        Some(Def(ModuleDef::EnumVariant(_))) => "constant",
+                        Some(Def(ModuleDef::Const(_))) => "constant",
+                        Some(Def(ModuleDef::Static(_))) => "constant",
+                        Some(Def(ModuleDef::Trait(_))) => "type",
+                        Some(Def(ModuleDef::TypeAlias(_))) => "type",
+                        Some(Def(ModuleDef::BuiltinType(_))) => "type",
+                        Some(SelfType(_)) => "type",
+                        Some(Pat(ptr)) => {
+                            binding_hash = Some({
+                                let text = ptr
+                                    .syntax_node_ptr()
+                                    .to_node(&source_file.syntax())
+                                    .text()
+                                    .to_smol_string();
+                                let shadow_count =
+                                    bindings_shadow_count.entry(text.clone()).or_default();
+                                calc_binding_hash(file_id, &text, *shadow_count)
+                            });
 
-                                "variable"
-                            }
-                            Some(SelfParam(_)) => "type",
-                            Some(GenericParam(_)) => "type",
-                            None => "text",
+                            "variable"
                         }
+                        Some(SelfParam(_)) => "type",
+                        Some(GenericParam(_)) => "type",
+                        None => "text",
                     }
                 } else {
                     "text"
diff --git a/crates/ra_lsp_server/src/conv.rs b/crates/ra_lsp_server/src/conv.rs
index 50a12ddbc..1b349d02a 100644
--- a/crates/ra_lsp_server/src/conv.rs
+++ b/crates/ra_lsp_server/src/conv.rs
@@ -65,6 +65,7 @@ impl Conv for CompletionItemKind {
             CompletionItemKind::Struct => Struct,
             CompletionItemKind::Enum => Enum,
             CompletionItemKind::EnumVariant => EnumMember,
+            CompletionItemKind::BuiltinType => Struct,
             CompletionItemKind::Binding => Variable,
             CompletionItemKind::Field => Field,
             CompletionItemKind::Trait => Interface,