11 files changed, 300 insertions, 76 deletions

diff --git a/crates/hir_def/Cargo.toml b/crates/hir_def/Cargo.toml
index a88b5f57e..e8b581e2f 100644
--- a/crates/hir_def/Cargo.toml
+++ b/crates/hir_def/Cargo.toml
@@ -17,7 +17,7 @@ either = "1.5.3"
 anymap = "0.12.1"
 drop_bomb = "0.1.4"
 fst = { version = "0.4", default-features = false }
-itertools = "0.9.0"
+itertools = "0.10.0"
 indexmap = "1.4.0"
 smallvec = "1.4.0"
 
diff --git a/crates/hir_def/src/attr.rs b/crates/hir_def/src/attr.rs
index 042e119b1..6b79e7bad 100644
--- a/crates/hir_def/src/attr.rs
+++ b/crates/hir_def/src/attr.rs
@@ -21,7 +21,7 @@ use crate::{
     nameres::ModuleSource,
     path::{ModPath, PathKind},
     src::HasChildSource,
-    AdtId, AttrDefId, Lookup,
+    AdtId, AttrDefId, GenericParamId, Lookup,
 };
 
 /// Holds documentation
@@ -235,6 +235,25 @@ impl Attrs {
             AttrDefId::StaticId(it) => attrs_from_item_tree(it.lookup(db).id, db),
             AttrDefId::FunctionId(it) => attrs_from_item_tree(it.lookup(db).id, db),
             AttrDefId::TypeAliasId(it) => attrs_from_item_tree(it.lookup(db).id, db),
+            AttrDefId::GenericParamId(it) => match it {
+                GenericParamId::TypeParamId(it) => {
+                    let src = it.parent.child_source(db);
+                    RawAttrs::from_attrs_owner(
+                        db,
+                        src.with_value(
+                            src.value[it.local_id].as_ref().either(|it| it as _, |it| it as _),
+                        ),
+                    )
+                }
+                GenericParamId::LifetimeParamId(it) => {
+                    let src = it.parent.child_source(db);
+                    RawAttrs::from_attrs_owner(db, src.with_value(&src.value[it.local_id]))
+                }
+                GenericParamId::ConstParamId(it) => {
+                    let src = it.parent.child_source(db);
+                    RawAttrs::from_attrs_owner(db, src.with_value(&src.value[it.local_id]))
+                }
+            },
         };
 
         raw_attrs.filter(db, def.krate(db))
@@ -260,14 +279,13 @@ impl Attrs {
     }
 
     pub fn docs(&self) -> Option<Documentation> {
-        let docs = self
-            .by_key("doc")
-            .attrs()
-            .flat_map(|attr| match attr.input.as_ref()? {
-                AttrInput::Literal(s) => Some(s),
-                AttrInput::TokenTree(_) => None,
-            })
-            .intersperse(&SmolStr::new_inline("\n"))
+        let docs = self.by_key("doc").attrs().flat_map(|attr| match attr.input.as_ref()? {
+            AttrInput::Literal(s) => Some(s),
+            AttrInput::TokenTree(_) => None,
+        });
+        // FIXME: Replace `Itertools::intersperse` with `Iterator::intersperse[_with]` until the
+        // libstd api gets stabilized (https://github.com/rust-lang/rust/issues/79524).
+        let docs = Itertools::intersperse(docs, &SmolStr::new_inline("\n"))
             .map(|it| it.as_str())
             .collect::<String>();
         if docs.is_empty() {
diff --git a/crates/hir_def/src/generics.rs b/crates/hir_def/src/generics.rs
index bb8fca009..9b5b886c2 100644
--- a/crates/hir_def/src/generics.rs
+++ b/crates/hir_def/src/generics.rs
@@ -21,11 +21,11 @@ use crate::{
     keys,
     src::{HasChildSource, HasSource},
     type_ref::{LifetimeRef, TypeBound, TypeRef},
-    AdtId, GenericDefId, LifetimeParamId, LocalLifetimeParamId, LocalTypeParamId, Lookup,
-    TypeParamId,
+    AdtId, ConstParamId, GenericDefId, LifetimeParamId, LocalConstParamId, LocalLifetimeParamId,
+    LocalTypeParamId, Lookup, TypeParamId,
 };
 
-/// Data about a generic parameter (to a function, struct, impl, ...).
+/// Data about a generic type parameter (to a function, struct, impl, ...).
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct TypeParamData {
     pub name: Option<Name>,
@@ -33,12 +33,19 @@ pub struct TypeParamData {
     pub provenance: TypeParamProvenance,
 }
 
-/// Data about a generic parameter (to a function, struct, impl, ...).
+/// Data about a generic lifetime parameter (to a function, struct, impl, ...).
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct LifetimeParamData {
     pub name: Name,
 }
 
+/// Data about a generic const parameter (to a function, struct, impl, ...).
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct ConstParamData {
+    pub name: Name,
+    pub ty: TypeRef,
+}
+
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 pub enum TypeParamProvenance {
     TypeParamList,
@@ -51,6 +58,7 @@ pub enum TypeParamProvenance {
 pub struct GenericParams {
     pub types: Arena<TypeParamData>,
     pub lifetimes: Arena<LifetimeParamData>,
+    pub consts: Arena<ConstParamData>,
     pub where_predicates: Vec<WherePredicate>,
 }
 
@@ -76,6 +84,7 @@ pub enum WherePredicateTypeTarget {
 pub(crate) struct SourceMap {
     pub(crate) type_params: ArenaMap<LocalTypeParamId, Either<ast::Trait, ast::TypeParam>>,
     lifetime_params: ArenaMap<LocalLifetimeParamId, ast::LifetimeParam>,
+    const_params: ArenaMap<LocalConstParamId, ast::ConstParam>,
 }
 
 impl GenericParams {
@@ -268,6 +277,13 @@ impl GenericParams {
             let lifetime_ref = LifetimeRef::new_name(name);
             self.fill_bounds(&lower_ctx, &lifetime_param, Either::Right(lifetime_ref));
         }
+        for const_param in params.const_params() {
+            let name = const_param.name().map_or_else(Name::missing, |it| it.as_name());
+            let ty = const_param.ty().map_or(TypeRef::Error, |it| TypeRef::from_ast(lower_ctx, it));
+            let param = ConstParamData { name, ty };
+            let param_id = self.consts.alloc(param);
+            sm.const_params.insert(param_id, const_param.clone());
+        }
     }
 
     fn fill_where_predicates(&mut self, lower_ctx: &LowerCtx, where_clause: ast::WhereClause) {
@@ -353,12 +369,16 @@ impl GenericParams {
         });
     }
 
-    pub fn find_by_name(&self, name: &Name) -> Option<LocalTypeParamId> {
+    pub fn find_type_by_name(&self, name: &Name) -> Option<LocalTypeParamId> {
         self.types
             .iter()
             .find_map(|(id, p)| if p.name.as_ref() == Some(name) { Some(id) } else { None })
     }
 
+    pub fn find_const_by_name(&self, name: &Name) -> Option<LocalConstParamId> {
+        self.consts.iter().find_map(|(id, p)| if p.name == *name { Some(id) } else { None })
+    }
+
     pub fn find_trait_self_param(&self) -> Option<LocalTypeParamId> {
         self.types.iter().find_map(|(id, p)| {
             if p.provenance == TypeParamProvenance::TraitSelf {
@@ -390,6 +410,16 @@ impl HasChildSource<LocalLifetimeParamId> for GenericDefId {
     }
 }
 
+impl HasChildSource<LocalConstParamId> for GenericDefId {
+    type Value = ast::ConstParam;
+    fn child_source(
+        &self,
+        db: &dyn DefDatabase,
+    ) -> InFile<ArenaMap<LocalConstParamId, Self::Value>> {
+        GenericParams::new(db, *self).1.map(|source_maps| source_maps.const_params)
+    }
+}
+
 impl ChildBySource for GenericDefId {
     fn child_by_source(&self, db: &dyn DefDatabase) -> DynMap {
         let mut res = DynMap::default();
@@ -406,6 +436,10 @@ impl ChildBySource for GenericDefId {
             let id = LifetimeParamId { parent: *self, local_id };
             res[keys::LIFETIME_PARAM].insert(sm.with_value(src.clone()), id);
         }
+        for (local_id, src) in sm.value.const_params.iter() {
+            let id = ConstParamId { parent: *self, local_id };
+            res[keys::CONST_PARAM].insert(sm.with_value(src.clone()), id);
+        }
         res
     }
 }
diff --git a/crates/hir_def/src/import_map.rs b/crates/hir_def/src/import_map.rs
index c0f108848..30b22f51d 100644
--- a/crates/hir_def/src/import_map.rs
+++ b/crates/hir_def/src/import_map.rs
@@ -238,32 +238,53 @@ pub enum ImportKind {
     BuiltinType,
 }
 
+/// A way to match import map contents against the search query.
+#[derive(Debug)]
+pub enum SearchMode {
+    /// Import map entry should strictly match the query string.
+    Equals,
+    /// Import map entry should contain the query string.
+    Contains,
+    /// Import map entry should contain all letters from the query string,
+    /// in the same order, but not necessary adjacent.
+    Fuzzy,
+}
+
 #[derive(Debug)]
 pub struct Query {
     query: String,
     lowercased: String,
-    anchor_end: bool,
+    name_only: bool,
+    search_mode: SearchMode,
     case_sensitive: bool,
     limit: usize,
     exclude_import_kinds: FxHashSet<ImportKind>,
 }
 
 impl Query {
-    pub fn new(query: &str) -> Self {
+    pub fn new(query: String) -> Self {
+        let lowercased = query.to_lowercase();
         Self {
-            lowercased: query.to_lowercase(),
-            query: query.to_string(),
-            anchor_end: false,
+            query,
+            lowercased,
+            name_only: false,
+            search_mode: SearchMode::Contains,
             case_sensitive: false,
             limit: usize::max_value(),
             exclude_import_kinds: FxHashSet::default(),
         }
     }
 
-    /// Only returns items whose paths end with the (case-insensitive) query string as their last
-    /// segment.
-    pub fn anchor_end(self) -> Self {
-        Self { anchor_end: true, ..self }
+    /// Matches entries' names only, ignoring the rest of
+    /// the qualifier.
+    /// Example: for `std::marker::PhantomData`, the name is `PhantomData`.
+    pub fn name_only(self) -> Self {
+        Self { name_only: true, ..self }
+    }
+
+    /// Specifies the way to search for the entries using the query.
+    pub fn search_mode(self, search_mode: SearchMode) -> Self {
+        Self { search_mode, ..self }
     }
 
     /// Limits the returned number of items to `limit`.
@@ -283,6 +304,40 @@ impl Query {
     }
 }
 
+fn contains_query(query: &Query, input_path: &ImportPath, enforce_lowercase: bool) -> bool {
+    let mut input = if query.name_only {
+        input_path.segments.last().unwrap().to_string()
+    } else {
+        input_path.to_string()
+    };
+    if enforce_lowercase || !query.case_sensitive {
+        input.make_ascii_lowercase();
+    }
+
+    let query_string =
+        if !enforce_lowercase && query.case_sensitive { &query.query } else { &query.lowercased };
+
+    match query.search_mode {
+        SearchMode::Equals => &input == query_string,
+        SearchMode::Contains => input.contains(query_string),
+        SearchMode::Fuzzy => {
+            let mut unchecked_query_chars = query_string.chars();
+            let mut mismatching_query_char = unchecked_query_chars.next();
+
+            for input_char in input.chars() {
+                match mismatching_query_char {
+                    None => return true,
+                    Some(matching_query_char) if matching_query_char == input_char => {
+                        mismatching_query_char = unchecked_query_chars.next();
+                    }
+                    _ => (),
+                }
+            }
+            mismatching_query_char.is_none()
+        }
+    }
+}
+
 /// Searches dependencies of `krate` for an importable path matching `query`.
 ///
 /// This returns a list of items that could be imported from dependencies of `krate`.
@@ -312,39 +367,29 @@ pub fn search_dependencies<'a>(
             let importables = &import_map.importables[indexed_value.value as usize..];
 
             // Path shared by the importable items in this group.
-            let path = &import_map.map[&importables[0]].path;
-
-            if query.anchor_end {
-                // Last segment must match query.
-                let last = path.segments.last().unwrap().to_string();
-                if last.to_lowercase() != query.lowercased {
-                    continue;
-                }
+            let common_importables_path = &import_map.map[&importables[0]].path;
+            if !contains_query(&query, common_importables_path, true) {
+                continue;
             }
 
+            let common_importables_path_fst = fst_path(common_importables_path);
             // Add the items from this `ModPath` group. Those are all subsequent items in
             // `importables` whose paths match `path`.
             let iter = importables
                 .iter()
                 .copied()
                 .take_while(|item| {
-                    let item_path = &import_map.map[item].path;
-                    fst_path(item_path) == fst_path(path)
+                    common_importables_path_fst == fst_path(&import_map.map[item].path)
                 })
                 .filter(|&item| match item_import_kind(item) {
                     Some(import_kind) => !query.exclude_import_kinds.contains(&import_kind),
                     None => true,
+                })
+                .filter(|item| {
+                    !query.case_sensitive // we've already checked the common importables path case-insensitively
+                        || contains_query(&query, &import_map.map[item].path, false)
                 });
-
-            if query.case_sensitive {
-                // FIXME: This does not do a subsequence match.
-                res.extend(iter.filter(|item| {
-                    let item_path = &import_map.map[item].path;
-                    item_path.to_string().contains(&query.query)
-                }));
-            } else {
-                res.extend(iter);
-            }
+            res.extend(iter);
 
             if res.len() >= query.limit {
                 res.truncate(query.limit);
@@ -387,8 +432,9 @@ fn item_import_kind(item: ItemInNs) -> Option<ImportKind> {
 mod tests {
     use base_db::{fixture::WithFixture, SourceDatabase, Upcast};
     use expect_test::{expect, Expect};
+    use stdx::format_to;
 
-    use crate::{test_db::TestDB, AssocContainerId, Lookup};
+    use crate::{data::FunctionData, test_db::TestDB, AssocContainerId, Lookup};
 
     use super::*;
 
@@ -407,14 +453,32 @@ mod tests {
             .into_iter()
             .filter_map(|item| {
                 let mark = match item {
+                    ItemInNs::Types(ModuleDefId::FunctionId(_))
+                    | ItemInNs::Values(ModuleDefId::FunctionId(_)) => "f",
                     ItemInNs::Types(_) => "t",
                     ItemInNs::Values(_) => "v",
                     ItemInNs::Macros(_) => "m",
                 };
-                let item = assoc_to_trait(&db, item);
                 item.krate(db.upcast()).map(|krate| {
                     let map = db.import_map(krate);
-                    let path = map.path_of(item).unwrap();
+
+                    let path = match assoc_to_trait(&db, item) {
+                        Some(trait_) => {
+                            let mut full_path = map.path_of(trait_).unwrap().to_string();
+                            if let ItemInNs::Types(ModuleDefId::FunctionId(function_id))
+                            | ItemInNs::Values(ModuleDefId::FunctionId(function_id)) = item
+                            {
+                                format_to!(
+                                    full_path,
+                                    "::{}",
+                                    FunctionData::fn_data_query(&db, function_id).name,
+                                );
+                            }
+                            full_path
+                        }
+                        None => map.path_of(item).unwrap().to_string(),
+                    };
+
                     format!(
                         "{}::{} ({})\n",
                         crate_graph[krate].display_name.as_ref().unwrap(),
@@ -427,15 +491,15 @@ mod tests {
         expect.assert_eq(&actual)
     }
 
-    fn assoc_to_trait(db: &dyn DefDatabase, item: ItemInNs) -> ItemInNs {
+    fn assoc_to_trait(db: &dyn DefDatabase, item: ItemInNs) -> Option<ItemInNs> {
         let assoc: AssocItemId = match item {
             ItemInNs::Types(it) | ItemInNs::Values(it) => match it {
                 ModuleDefId::TypeAliasId(it) => it.into(),
                 ModuleDefId::FunctionId(it) => it.into(),
                 ModuleDefId::ConstId(it) => it.into(),
-                _ => return item,
+                _ => return None,
             },
-            _ => return item,
+            _ => return None,
         };
 
         let container = match assoc {
@@ -445,8 +509,8 @@ mod tests {
         };
 
         match container {
-            AssocContainerId::TraitId(it) => ItemInNs::Types(it.into()),
-            _ => item,
+            AssocContainerId::TraitId(it) => Some(ItemInNs::Types(it.into())),
+            _ => None,
         }
     }
 
@@ -685,7 +749,7 @@ mod tests {
     }
 
     #[test]
-    fn search() {
+    fn search_mode() {
         let ra_fixture = r#"
             //- /main.rs crate:main deps:dep
             //- /dep.rs crate:dep deps:tdep
@@ -713,28 +777,96 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("fmt"),
+            Query::new("fmt".to_string()).search_mode(SearchMode::Fuzzy),
             expect![[r#"
                 dep::fmt (t)
                 dep::Fmt (t)
                 dep::Fmt (v)
                 dep::Fmt (m)
                 dep::fmt::Display (t)
-                dep::format (v)
+                dep::format (f)
+                dep::fmt::Display::fmt (f)
+            "#]],
+        );
+
+        check_search(
+            ra_fixture,
+            "main",
+            Query::new("fmt".to_string()).search_mode(SearchMode::Equals),
+            expect![[r#"
+                dep::fmt (t)
+                dep::Fmt (t)
+                dep::Fmt (v)
+                dep::Fmt (m)
+                dep::fmt::Display::fmt (f)
+            "#]],
+        );
+
+        check_search(
+            ra_fixture,
+            "main",
+            Query::new("fmt".to_string()).search_mode(SearchMode::Contains),
+            expect![[r#"
+                dep::fmt (t)
+                dep::Fmt (t)
+                dep::Fmt (v)
+                dep::Fmt (m)
                 dep::fmt::Display (t)
+                dep::fmt::Display::fmt (f)
             "#]],
         );
+    }
+
+    #[test]
+    fn name_only() {
+        let ra_fixture = r#"
+            //- /main.rs crate:main deps:dep
+            //- /dep.rs crate:dep deps:tdep
+            use tdep::fmt as fmt_dep;
+            pub mod fmt {
+                pub trait Display {
+                    fn fmt();
+                }
+            }
+            #[macro_export]
+            macro_rules! Fmt {
+                () => {};
+            }
+            pub struct Fmt;
+
+            pub fn format() {}
+            pub fn no() {}
+
+            //- /tdep.rs crate:tdep
+            pub mod fmt {
+                pub struct NotImportableFromMain;
+            }
+        "#;
 
         check_search(
             ra_fixture,
             "main",
-            Query::new("fmt").anchor_end(),
+            Query::new("fmt".to_string()),
             expect![[r#"
                 dep::fmt (t)
                 dep::Fmt (t)
                 dep::Fmt (v)
                 dep::Fmt (m)
                 dep::fmt::Display (t)
+                dep::fmt::Display::fmt (f)
+            "#]],
+        );
+
+        check_search(
+            ra_fixture,
+            "main",
+            Query::new("fmt".to_string()).name_only(),
+            expect![[r#"
+                dep::fmt (t)
+                dep::Fmt (t)
+                dep::Fmt (v)
+                dep::Fmt (m)
+                dep::fmt::Display::fmt (f)
             "#]],
         );
     }
@@ -752,7 +884,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT"),
+            Query::new("FMT".to_string()),
             expect![[r#"
                 dep::fmt (t)
                 dep::fmt (v)
@@ -764,7 +896,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT").case_sensitive(),
+            Query::new("FMT".to_string()).case_sensitive(),
             expect![[r#"
                 dep::FMT (t)
                 dep::FMT (v)
@@ -793,7 +925,7 @@ mod tests {
         pub fn no() {}
     "#,
             "main",
-            Query::new("").limit(2),
+            Query::new("".to_string()).limit(2),
             expect![[r#"
                 dep::fmt (t)
                 dep::Fmt (t)
@@ -814,7 +946,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT"),
+            Query::new("FMT".to_string()),
             expect![[r#"
                 dep::fmt (t)
                 dep::fmt (v)
@@ -826,7 +958,7 @@ mod tests {
         check_search(
             ra_fixture,
             "main",
-            Query::new("FMT").exclude_import_kind(ImportKind::Adt),
+            Query::new("FMT".to_string()).exclude_import_kind(ImportKind::Adt),
             expect![[r#""#]],
         );
     }
diff --git a/crates/hir_def/src/item_tree.rs b/crates/hir_def/src/item_tree.rs
index 100dbf5d6..b6f510731 100644
--- a/crates/hir_def/src/item_tree.rs
+++ b/crates/hir_def/src/item_tree.rs
@@ -260,6 +260,7 @@ impl GenericParamsStorage {
     fn alloc(&mut self, params: GenericParams) -> GenericParamsId {
         if params.types.is_empty()
             && params.lifetimes.is_empty()
+            && params.consts.is_empty()
             && params.where_predicates.is_empty()
         {
             return GenericParamsId::EMPTY;
@@ -269,8 +270,12 @@ impl GenericParamsStorage {
     }
 }
 
-static EMPTY_GENERICS: GenericParams =
-    GenericParams { types: Arena::new(), lifetimes: Arena::new(), where_predicates: Vec::new() };
+static EMPTY_GENERICS: GenericParams = GenericParams {
+    types: Arena::new(),
+    lifetimes: Arena::new(),
+    consts: Arena::new(),
+    where_predicates: Vec::new(),
+};
 
 #[derive(Default, Debug, Eq, PartialEq)]
 struct ItemTreeData {
diff --git a/crates/hir_def/src/keys.rs b/crates/hir_def/src/keys.rs
index 9c585de2c..89b3ed868 100644
--- a/crates/hir_def/src/keys.rs
+++ b/crates/hir_def/src/keys.rs
@@ -8,8 +8,8 @@ use syntax::{ast, AstNode, AstPtr};
 
 use crate::{
     dyn_map::{DynMap, Policy},
-    ConstId, EnumId, EnumVariantId, FieldId, FunctionId, ImplId, LifetimeParamId, StaticId,
-    StructId, TraitId, TypeAliasId, TypeParamId, UnionId,
+    ConstId, ConstParamId, EnumId, EnumVariantId, FieldId, FunctionId, ImplId, LifetimeParamId,
+    StaticId, StructId, TraitId, TypeAliasId, TypeParamId, UnionId,
 };
 
 pub type Key<K, V> = crate::dyn_map::Key<InFile<K>, V, AstPtrPolicy<K, V>>;
@@ -29,6 +29,7 @@ pub const TUPLE_FIELD: Key<ast::TupleField, FieldId> = Key::new();
 pub const RECORD_FIELD: Key<ast::RecordField, FieldId> = Key::new();
 pub const TYPE_PARAM: Key<ast::TypeParam, TypeParamId> = Key::new();
 pub const LIFETIME_PARAM: Key<ast::LifetimeParam, LifetimeParamId> = Key::new();
+pub const CONST_PARAM: Key<ast::ConstParam, ConstParamId> = Key::new();
 
 pub const MACRO: Key<ast::MacroCall, MacroDefId> = Key::new();
 
diff --git a/crates/hir_def/src/lib.rs b/crates/hir_def/src/lib.rs
index ba09a9126..211cb2faf 100644
--- a/crates/hir_def/src/lib.rs
+++ b/crates/hir_def/src/lib.rs
@@ -232,6 +232,13 @@ pub struct LifetimeParamId {
 pub type LocalLifetimeParamId = Idx<generics::LifetimeParamData>;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct ConstParamId {
+    pub parent: GenericDefId,
+    pub local_id: LocalConstParamId,
+}
+pub type LocalConstParamId = Idx<generics::ConstParamData>;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum ContainerId {
     ModuleId(ModuleId),
     DefWithBodyId(DefWithBodyId),
@@ -254,6 +261,15 @@ pub enum AdtId {
 }
 impl_from!(StructId, UnionId, EnumId for AdtId);
 
+/// A generic param
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub enum GenericParamId {
+    TypeParamId(TypeParamId),
+    LifetimeParamId(LifetimeParamId),
+    ConstParamId(ConstParamId),
+}
+impl_from!(TypeParamId, LifetimeParamId, ConstParamId for GenericParamId);
+
 /// The defs which can be visible in the module.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum ModuleDefId {
@@ -350,6 +366,7 @@ pub enum AttrDefId {
     TypeAliasId(TypeAliasId),
     MacroDefId(MacroDefId),
     ImplId(ImplId),
+    GenericParamId(GenericParamId),
 }
 
 impl_from!(
@@ -363,7 +380,8 @@ impl_from!(
     TraitId,
     TypeAliasId,
     MacroDefId,
-    ImplId
+    ImplId,
+    GenericParamId
     for AttrDefId
 );
 
@@ -488,6 +506,15 @@ impl AttrDefId {
             AttrDefId::TraitId(it) => it.lookup(db).container.module(db).krate,
             AttrDefId::TypeAliasId(it) => it.lookup(db).module(db).krate,
             AttrDefId::ImplId(it) => it.lookup(db).container.module(db).krate,
+            AttrDefId::GenericParamId(it) => {
+                match it {
+                    GenericParamId::TypeParamId(it) => it.parent,
+                    GenericParamId::LifetimeParamId(it) => it.parent,
+                    GenericParamId::ConstParamId(it) => it.parent,
+                }
+                .module(db)
+                .krate
+            }
             // FIXME: `MacroDefId` should store the defining module, then this can implement
             // `HasModule`
             AttrDefId::MacroDefId(it) => it.krate,
diff --git a/crates/hir_def/src/nameres.rs b/crates/hir_def/src/nameres.rs
index ffd0381d4..5682e122d 100644
--- a/crates/hir_def/src/nameres.rs
+++ b/crates/hir_def/src/nameres.rs
@@ -249,7 +249,7 @@ impl CrateDefMap {
                     buf.push_str(" _");
                 }
 
-                buf.push_str("\n");
+                buf.push('\n');
             }
 
             for (name, child) in map.modules[module].children.iter() {
@@ -454,7 +454,7 @@ mod diagnostics {
                                     });
                                 for token in tokens {
                                     if token.kind() == SyntaxKind::IDENT
-                                        && token.to_string() == *name
+                                        && token.text() == name.as_str()
                                     {
                                         precise_location = Some(token.text_range());
                                         break 'outer;
diff --git a/crates/hir_def/src/nameres/tests/macros.rs b/crates/hir_def/src/nameres/tests/macros.rs
index f9bf5bc72..e5e9e8ca1 100644
--- a/crates/hir_def/src/nameres/tests/macros.rs
+++ b/crates/hir_def/src/nameres/tests/macros.rs
@@ -677,7 +677,7 @@ fn macro_expansion_overflow() {
         r#"
 macro_rules! a {
     ($e:expr; $($t:tt)*) => {
-        b!($($t)*);
+        b!(static = (); $($t)*);
     };
     () => {};
 }
@@ -689,7 +689,7 @@ macro_rules! b {
     () => {};
 }
 
-b! { static = #[] (); }
+b! { static = #[] ();}
 "#,
         expect![[r#"
             crate
diff --git a/crates/hir_def/src/path/lower.rs b/crates/hir_def/src/path/lower.rs
index 8a01e6eea..9518ac109 100644
--- a/crates/hir_def/src/path/lower.rs
+++ b/crates/hir_def/src/path/lower.rs
@@ -123,7 +123,7 @@ pub(super) fn lower_path(mut path: ast::Path, hygiene: &Hygiene) -> Option<Path>
     // We follow what it did anyway :)
     if segments.len() == 1 && kind == PathKind::Plain {
         if let Some(_macro_call) = path.syntax().parent().and_then(ast::MacroCall::cast) {
-            if let Some(crate_id) = hygiene.local_inner_macros() {
+            if let Some(crate_id) = hygiene.local_inner_macros(path) {
                 kind = PathKind::DollarCrate(crate_id);
             }
         }
diff --git a/crates/hir_def/src/resolver.rs b/crates/hir_def/src/resolver.rs
index f8cc5e075..129f1dbac 100644
--- a/crates/hir_def/src/resolver.rs
+++ b/crates/hir_def/src/resolver.rs
@@ -20,9 +20,9 @@ use crate::{
     path::{ModPath, PathKind},
     per_ns::PerNs,
     visibility::{RawVisibility, Visibility},
-    AdtId, AssocContainerId, ConstId, ContainerId, DefWithBodyId, EnumId, EnumVariantId,
-    FunctionId, GenericDefId, HasModule, ImplId, LocalModuleId, Lookup, ModuleDefId, ModuleId,
-    StaticId, StructId, TraitId, TypeAliasId, TypeParamId, VariantId,
+    AdtId, AssocContainerId, ConstId, ConstParamId, ContainerId, DefWithBodyId, EnumId,
+    EnumVariantId, FunctionId, GenericDefId, HasModule, ImplId, LocalModuleId, Lookup, ModuleDefId,
+    ModuleId, StaticId, StructId, TraitId, TypeAliasId, TypeParamId, VariantId,
 };
 
 #[derive(Debug, Clone, Default)]
@@ -93,6 +93,7 @@ pub enum ValueNs {
     StaticId(StaticId),
     StructId(StructId),
     EnumVariantId(EnumVariantId),
+    GenericParam(ConstParamId),
 }
 
 impl Resolver {
@@ -163,7 +164,7 @@ impl Resolver {
                 }
 
                 Scope::GenericParams { params, def } => {
-                    if let Some(local_id) = params.find_by_name(first_name) {
+                    if let Some(local_id) = params.find_type_by_name(first_name) {
                         let idx = if path.segments.len() == 1 { None } else { Some(1) };
                         return Some((
                             TypeNs::GenericParam(TypeParamId { local_id, parent: *def }),
@@ -285,11 +286,17 @@ impl Resolver {
                 Scope::ExprScope(_) => continue,
 
                 Scope::GenericParams { params, def } if n_segments > 1 => {
-                    if let Some(local_id) = params.find_by_name(first_name) {
+                    if let Some(local_id) = params.find_type_by_name(first_name) {
                         let ty = TypeNs::GenericParam(TypeParamId { local_id, parent: *def });
                         return Some(ResolveValueResult::Partial(ty, 1));
                     }
                 }
+                Scope::GenericParams { params, def } if n_segments == 1 => {
+                    if let Some(local_id) = params.find_const_by_name(first_name) {
+                        let val = ValueNs::GenericParam(ConstParamId { local_id, parent: *def });
+                        return Some(ResolveValueResult::ValueNs(val));
+                    }
+                }
                 Scope::GenericParams { .. } => continue,
 
                 Scope::ImplDefScope(impl_) => {