5 files changed, 149 insertions, 26 deletions

diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index af59aa1b6..4a06f3bcd 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -19,11 +19,14 @@ use hir_def::{
 use hir_expand::{
     diagnostics::DiagnosticSink,
     name::{name, AsName},
-    MacroDefId,
+    MacroDefId, MacroDefKind,
 };
 use hir_ty::{
-    autoderef, display::HirFormatter, expr::ExprValidator, method_resolution, ApplicationTy,
-    Canonical, InEnvironment, Substs, TraitEnvironment, Ty, TyDefId, TypeCtor,
+    autoderef,
+    display::{HirDisplayError, HirFormatter},
+    expr::ExprValidator,
+    method_resolution, ApplicationTy, Canonical, InEnvironment, Substs, TraitEnvironment, Ty,
+    TyDefId, TypeCtor,
 };
 use ra_db::{CrateId, CrateName, Edition, FileId};
 use ra_prof::profile;
@@ -145,6 +148,26 @@ impl ModuleDef {
             ModuleDef::BuiltinType(_) => None,
         }
     }
+
+    pub fn definition_visibility(&self, db: &dyn HirDatabase) -> Option<Visibility> {
+        let module = match self {
+            ModuleDef::Module(it) => it.parent(db)?,
+            ModuleDef::Function(it) => return Some(it.visibility(db)),
+            ModuleDef::Adt(it) => it.module(db),
+            ModuleDef::EnumVariant(it) => {
+                let parent = it.parent_enum(db);
+                let module = it.module(db);
+                return module.visibility_of(db, &ModuleDef::Adt(Adt::Enum(parent)));
+            }
+            ModuleDef::Const(it) => return Some(it.visibility(db)),
+            ModuleDef::Static(it) => it.module(db),
+            ModuleDef::Trait(it) => it.module(db),
+            ModuleDef::TypeAlias(it) => return Some(it.visibility(db)),
+            ModuleDef::BuiltinType(_) => return None,
+        };
+
+        module.visibility_of(db, self)
+    }
 }
 
 pub use hir_def::{
@@ -509,7 +532,7 @@ impl Adt {
         Some(self.module(db).krate())
     }
 
-    pub fn name(&self, db: &dyn HirDatabase) -> Name {
+    pub fn name(self, db: &dyn HirDatabase) -> Name {
         match self {
             Adt::Struct(s) => s.name(db),
             Adt::Union(u) => u.name(db),
@@ -614,6 +637,10 @@ impl Function {
         db.function_data(self.id).params.clone()
     }
 
+    pub fn is_unsafe(self, db: &dyn HirDatabase) -> bool {
+        db.function_data(self.id).is_unsafe
+    }
+
     pub fn diagnostics(self, db: &dyn HirDatabase, sink: &mut DiagnosticSink) {
         let _p = profile("Function::diagnostics");
         let infer = db.infer(self.id.into());
@@ -675,6 +702,10 @@ impl Static {
     pub fn name(self, db: &dyn HirDatabase) -> Option<Name> {
         db.static_data(self.id).name.clone()
     }
+
+    pub fn is_mut(self, db: &dyn HirDatabase) -> bool {
+        db.static_data(self.id).mutable
+    }
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
@@ -762,13 +793,12 @@ impl MacroDef {
 
     /// Indicate it is a proc-macro
     pub fn is_proc_macro(&self) -> bool {
-        match self.id.kind {
-            hir_expand::MacroDefKind::Declarative => false,
-            hir_expand::MacroDefKind::BuiltIn(_) => false,
-            hir_expand::MacroDefKind::BuiltInDerive(_) => false,
-            hir_expand::MacroDefKind::BuiltInEager(_) => false,
-            hir_expand::MacroDefKind::CustomDerive(_) => true,
-        }
+        matches!(self.id.kind, MacroDefKind::CustomDerive(_))
+    }
+
+    /// Indicate it is a derive macro
+    pub fn is_derive_macro(&self) -> bool {
+        matches!(self.id.kind, MacroDefKind::CustomDerive(_) | MacroDefKind::BuiltInDerive(_))
     }
 }
 
@@ -963,6 +993,17 @@ impl TypeParam {
             ty: InEnvironment { value: ty, environment },
         }
     }
+
+    pub fn default(self, db: &dyn HirDatabase) -> Option<Type> {
+        let params = db.generic_defaults(self.id.parent);
+        let local_idx = hir_ty::param_idx(db, self.id)?;
+        let resolver = self.id.parent.resolver(db.upcast());
+        let environment = TraitEnvironment::lower(db, &resolver);
+        params.get(local_idx).cloned().map(|ty| Type {
+            krate: self.id.parent.module(db.upcast()).krate,
+            ty: InEnvironment { value: ty, environment },
+        })
+    }
 }
 
 // FIXME: rename from `ImplDef` to `Impl`
@@ -981,15 +1022,15 @@ impl ImplDef {
         impls.lookup_impl_defs_for_trait(trait_.id).map(Self::from).collect()
     }
 
-    pub fn target_trait(&self, db: &dyn HirDatabase) -> Option<TypeRef> {
+    pub fn target_trait(self, db: &dyn HirDatabase) -> Option<TypeRef> {
         db.impl_data(self.id).target_trait.clone()
     }
 
-    pub fn target_type(&self, db: &dyn HirDatabase) -> TypeRef {
+    pub fn target_type(self, db: &dyn HirDatabase) -> TypeRef {
         db.impl_data(self.id).target_type.clone()
     }
 
-    pub fn target_ty(&self, db: &dyn HirDatabase) -> Type {
+    pub fn target_ty(self, db: &dyn HirDatabase) -> Type {
         let impl_data = db.impl_data(self.id);
         let resolver = self.id.resolver(db.upcast());
         let ctx = hir_ty::TyLoweringContext::new(db, &resolver);
@@ -1001,23 +1042,23 @@ impl ImplDef {
         }
     }
 
-    pub fn items(&self, db: &dyn HirDatabase) -> Vec<AssocItem> {
+    pub fn items(self, db: &dyn HirDatabase) -> Vec<AssocItem> {
         db.impl_data(self.id).items.iter().map(|it| (*it).into()).collect()
     }
 
-    pub fn is_negative(&self, db: &dyn HirDatabase) -> bool {
+    pub fn is_negative(self, db: &dyn HirDatabase) -> bool {
         db.impl_data(self.id).is_negative
     }
 
-    pub fn module(&self, db: &dyn HirDatabase) -> Module {
+    pub fn module(self, db: &dyn HirDatabase) -> Module {
         self.id.lookup(db.upcast()).container.module(db.upcast()).into()
     }
 
-    pub fn krate(&self, db: &dyn HirDatabase) -> Crate {
+    pub fn krate(self, db: &dyn HirDatabase) -> Crate {
         Crate { id: self.module(db).id.krate }
     }
 
-    pub fn is_builtin_derive(&self, db: &dyn HirDatabase) -> Option<InFile<ast::Attr>> {
+    pub fn is_builtin_derive(self, db: &dyn HirDatabase) -> Option<InFile<ast::Attr>> {
         let src = self.source(db);
         let item = src.file_id.is_builtin_derive(db.upcast())?;
         let hygenic = hir_expand::hygiene::Hygiene::new(db.upcast(), item.file_id);
@@ -1153,6 +1194,10 @@ impl Type {
         )
     }
 
+    pub fn is_raw_ptr(&self) -> bool {
+        matches!(&self.ty.value, Ty::Apply(ApplicationTy { ctor: TypeCtor::RawPtr(..), .. }))
+    }
+
     pub fn contains_unknown(&self) -> bool {
         return go(&self.ty.value);
 
@@ -1212,7 +1257,7 @@ impl Type {
 
     // This would be nicer if it just returned an iterator, but that runs into
     // lifetime problems, because we need to borrow temp `CrateImplDefs`.
-    pub fn iterate_impl_items<T>(
+    pub fn iterate_assoc_items<T>(
         self,
         db: &dyn HirDatabase,
         krate: Crate,
@@ -1320,12 +1365,13 @@ impl Type {
 }
 
 impl HirDisplay for Type {
-    fn hir_fmt(&self, f: &mut HirFormatter) -> std::fmt::Result {
+    fn hir_fmt(&self, f: &mut HirFormatter) -> Result<(), HirDisplayError> {
         self.ty.value.hir_fmt(f)
     }
 }
 
 /// For IDE only
+#[derive(Debug)]
 pub enum ScopeDef {
     ModuleDef(ModuleDef),
     MacroDef(MacroDef),
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 312ef3814..3364a822f 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -62,6 +62,7 @@ pub use crate::{
 
 pub use hir_def::{
     adt::StructKind,
+    attr::Attrs,
     body::scope::ExprScopes,
     builtin_type::BuiltinType,
     docs::Documentation,
@@ -70,6 +71,7 @@ pub use hir_def::{
     type_ref::Mutability,
 };
 pub use hir_expand::{
-    name::Name, HirFileId, InFile, MacroCallId, MacroCallLoc, MacroDefId, MacroFile, Origin,
+    hygiene::Hygiene, name::Name, HirFileId, InFile, MacroCallId, MacroCallLoc, MacroDefId,
+    MacroFile, Origin,
 };
 pub use hir_ty::{display::HirDisplay, CallableDef};
diff --git a/crates/ra_hir/src/semantics.rs b/crates/ra_hir/src/semantics.rs
index a0a0f234b..7c1f79f27 100644
--- a/crates/ra_hir/src/semantics.rs
+++ b/crates/ra_hir/src/semantics.rs
@@ -8,7 +8,7 @@ use hir_def::{
     resolver::{self, HasResolver, Resolver},
     AsMacroCall, TraitId,
 };
-use hir_expand::ExpansionInfo;
+use hir_expand::{hygiene::Hygiene, ExpansionInfo};
 use hir_ty::associated_type_shorthand_candidates;
 use itertools::Itertools;
 use ra_db::{FileId, FileRange};
@@ -23,7 +23,7 @@ use crate::{
     db::HirDatabase,
     diagnostics::Diagnostic,
     semantics::source_to_def::{ChildContainer, SourceToDefCache, SourceToDefCtx},
-    source_analyzer::{resolve_hir_path, SourceAnalyzer},
+    source_analyzer::{resolve_hir_path, resolve_hir_path_qualifier, SourceAnalyzer},
     AssocItem, Field, Function, HirFileId, ImplDef, InFile, Local, MacroDef, Module, ModuleDef,
     Name, Origin, Path, ScopeDef, Trait, Type, TypeAlias, TypeParam,
 };
@@ -246,6 +246,11 @@ impl<'db, DB: HirDatabase> Semantics<'db, DB> {
         self.analyze(path.syntax()).resolve_path(self.db, path)
     }
 
+    pub fn lower_path(&self, path: &ast::Path) -> Option<Path> {
+        let src = self.find_file(path.syntax().clone());
+        Path::from_src(path.clone(), &Hygiene::new(self.db.upcast(), src.file_id.into()))
+    }
+
     pub fn resolve_bind_pat_to_const(&self, pat: &ast::BindPat) -> Option<ModuleDef> {
         self.analyze(pat.syntax()).resolve_bind_pat_to_const(self.db, pat)
     }
@@ -446,6 +451,23 @@ impl<'a, DB: HirDatabase> SemanticsScope<'a, DB> {
     pub fn resolve_hir_path(&self, path: &Path) -> Option<PathResolution> {
         resolve_hir_path(self.db, &self.resolver, path)
     }
+
+    /// Resolves a path where we know it is a qualifier of another path.
+    ///
+    /// For example, if we have:
+    /// ```
+    /// mod my {
+    ///     pub mod foo {
+    ///         struct Bar;
+    ///     }
+    ///
+    ///     pub fn foo() {}
+    /// }
+    /// ```
+    /// then we know that `foo` in `my::foo::Bar` refers to the module, not the function.
+    pub fn resolve_hir_path_qualifier(&self, path: &Path) -> Option<PathResolution> {
+        resolve_hir_path_qualifier(self.db, &self.resolver, path)
+    }
 }
 
 // FIXME: Change `HasSource` trait to work with `Semantics` and remove this?
diff --git a/crates/ra_hir/src/semantics/source_to_def.rs b/crates/ra_hir/src/semantics/source_to_def.rs
index 6f3b5b2da..8af64fdc1 100644
--- a/crates/ra_hir/src/semantics/source_to_def.rs
+++ b/crates/ra_hir/src/semantics/source_to_def.rs
@@ -151,7 +151,7 @@ impl SourceToDefCtx<'_, '_> {
         let krate = self.file_to_def(file_id)?.krate;
         let file_ast_id = self.db.ast_id_map(src.file_id).ast_id(&src.value);
         let ast_id = Some(AstId::new(src.file_id, file_ast_id));
-        Some(MacroDefId { krate: Some(krate), ast_id, kind })
+        Some(MacroDefId { krate: Some(krate), ast_id, kind, local_inner: false })
     }
 
     pub(super) fn find_container(&mut self, src: InFile<&SyntaxNode>) -> Option<ChildContainer> {
diff --git a/crates/ra_hir/src/source_analyzer.rs b/crates/ra_hir/src/source_analyzer.rs
index 74d64c97d..4b509f07c 100644
--- a/crates/ra_hir/src/source_analyzer.rs
+++ b/crates/ra_hir/src/source_analyzer.rs
@@ -224,7 +224,19 @@ impl SourceAnalyzer {
             }
         }
         // This must be a normal source file rather than macro file.
-        let hir_path = crate::Path::from_ast(path.clone())?;
+        let hir_path =
+            crate::Path::from_src(path.clone(), &Hygiene::new(db.upcast(), self.file_id))?;
+
+        // Case where path is a qualifier of another path, e.g. foo::bar::Baz where we
+        // trying to resolve foo::bar.
+        if let Some(outer_path) = path.syntax().parent().and_then(ast::Path::cast) {
+            if let Some(qualifier) = outer_path.qualifier() {
+                if path == &qualifier {
+                    return resolve_hir_path_qualifier(db, &self.resolver, &hir_path);
+                }
+            }
+        }
+
         resolve_hir_path(db, &self.resolver, &hir_path)
     }
 
@@ -403,6 +415,7 @@ pub(crate) fn resolve_hir_path(
             TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
             TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
         });
+
     let body_owner = resolver.body_owner();
     let values =
         resolver.resolve_path_in_value_ns_fully(db.upcast(), path.mod_path()).and_then(|val| {
@@ -416,6 +429,7 @@ pub(crate) fn resolve_hir_path(
                 ValueNs::StaticId(it) => PathResolution::Def(Static::from(it).into()),
                 ValueNs::StructId(it) => PathResolution::Def(Struct::from(it).into()),
                 ValueNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
+                ValueNs::ImplSelf(impl_id) => PathResolution::SelfType(impl_id.into()),
             };
             Some(res)
         });
@@ -424,9 +438,48 @@ pub(crate) fn resolve_hir_path(
         .resolve_module_path_in_items(db.upcast(), path.mod_path())
         .take_types()
         .map(|it| PathResolution::Def(it.into()));
+
     types.or(values).or(items).or_else(|| {
         resolver
             .resolve_path_as_macro(db.upcast(), path.mod_path())
             .map(|def| PathResolution::Macro(def.into()))
     })
 }
+
+/// Resolves a path where we know it is a qualifier of another path.
+///
+/// For example, if we have:
+/// ```
+/// mod my {
+///     pub mod foo {
+///         struct Bar;
+///     }
+///
+///     pub fn foo() {}
+/// }
+/// ```
+/// then we know that `foo` in `my::foo::Bar` refers to the module, not the function.
+pub(crate) fn resolve_hir_path_qualifier(
+    db: &dyn HirDatabase,
+    resolver: &Resolver,
+    path: &crate::Path,
+) -> Option<PathResolution> {
+    let items = resolver
+        .resolve_module_path_in_items(db.upcast(), path.mod_path())
+        .take_types()
+        .map(|it| PathResolution::Def(it.into()));
+
+    if items.is_some() {
+        return items;
+    }
+
+    resolver.resolve_path_in_type_ns_fully(db.upcast(), path.mod_path()).map(|ty| match ty {
+        TypeNs::SelfType(it) => PathResolution::SelfType(it.into()),
+        TypeNs::GenericParam(id) => PathResolution::TypeParam(TypeParam { id }),
+        TypeNs::AdtSelfType(it) | TypeNs::AdtId(it) => PathResolution::Def(Adt::from(it).into()),
+        TypeNs::EnumVariantId(it) => PathResolution::Def(EnumVariant::from(it).into()),
+        TypeNs::TypeAliasId(it) => PathResolution::Def(TypeAlias::from(it).into()),
+        TypeNs::BuiltinType(it) => PathResolution::Def(it.into()),
+        TypeNs::TraitId(it) => PathResolution::Def(Trait::from(it).into()),
+    })
+}