48 files changed, 1322 insertions, 792 deletions
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index ed9191c49..7f4e75341 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -116,9 +116,9 @@ jobs:
    - run: npm ci
      working-directory: ./editors/code
-    - run: npm audit || { sleep 10 && npm audit; } || { sleep 30 && npm audit; }
+#    - run: npm audit || { sleep 10 && npm audit; } || { sleep 30 && npm audit; }
-      if: runner.os == 'Linux'
+#      if: runner.os == 'Linux'
-      working-directory: ./editors/code
+#      working-directory: ./editors/code
    - run: npm run lint
      working-directory: ./editors/code
diff --git a/Cargo.lock b/Cargo.lock
index e1d2475e2..61ae8157a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1248,6 +1248,7 @@ dependencies = [
 "ra_syntax",
 "ra_text_edit",
 "rustc-hash",
+ "test_utils",
 ]
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 5278b5a16..189f4ea2b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,6 +24,8 @@ opt-level = 0
 opt-level = 0
 [profile.release.package.salsa-macros]
 opt-level = 0
+[profile.release.package.tracing-attributes]
+opt-level = 0
 [profile.release.package.xtask]
 opt-level = 0
diff --git a/crates/flycheck/src/lib.rs b/crates/flycheck/src/lib.rs
index 1023d3040..844b093d4 100644
--- a/crates/flycheck/src/lib.rs
+++ b/crates/flycheck/src/lib.rs
@@ -132,6 +132,7 @@ impl FlycheckActor {
                    self.cancel_check_process();
                    let mut command = self.check_command();
+                    log::info!("restart flycheck {:?}", command);
                    command.stdout(Stdio::piped()).stderr(Stdio::null()).stdin(Stdio::null());
                    if let Ok(child) = command.spawn().map(JodChild) {
                        self.cargo_handle = Some(CargoHandle::spawn(child));
diff --git a/crates/ra_assists/src/handlers/auto_import.rs b/crates/ra_assists/src/handlers/auto_import.rs
index 7b6499a08..4cd77adbf 100644
--- a/crates/ra_assists/src/handlers/auto_import.rs
+++ b/crates/ra_assists/src/handlers/auto_import.rs
@@ -811,6 +811,146 @@ fn main() {
    }
    #[test]
+    fn trait_method_cross_crate() {
+        check_assist(
+            auto_import,
+            r"
+            //- /main.rs crate:main deps:dep
+            fn main() {
+                let test_struct = dep::test_mod::TestStruct {};
+                test_struct.test_meth<|>od()
+            }
+            //- /dep.rs crate:dep
+            pub mod test_mod {
+                pub trait TestTrait {
+                    fn test_method(&self);
+                }
+                pub struct TestStruct {}
+                impl TestTrait for TestStruct {
+                    fn test_method(&self) {}
+                }
+            }
+            ",
+            r"
+            use dep::test_mod::TestTrait;
+            fn main() {
+                let test_struct = dep::test_mod::TestStruct {};
+                test_struct.test_method()
+            }
+            ",
+        );
+    }
+    #[test]
+    fn assoc_fn_cross_crate() {
+        check_assist(
+            auto_import,
+            r"
+            //- /main.rs crate:main deps:dep
+            fn main() {
+                dep::test_mod::TestStruct::test_func<|>tion
+            }
+            //- /dep.rs crate:dep
+            pub mod test_mod {
+                pub trait TestTrait {
+                    fn test_function();
+                }
+                pub struct TestStruct {}
+                impl TestTrait for TestStruct {
+                    fn test_function() {}
+                }
+            }
+            ",
+            r"
+            use dep::test_mod::TestTrait;
+            fn main() {
+                dep::test_mod::TestStruct::test_function
+            }
+            ",
+        );
+    }
+    #[test]
+    fn assoc_const_cross_crate() {
+        check_assist(
+            auto_import,
+            r"
+            //- /main.rs crate:main deps:dep
+            fn main() {
+                dep::test_mod::TestStruct::CONST<|>
+            }
+            //- /dep.rs crate:dep
+            pub mod test_mod {
+                pub trait TestTrait {
+                    const CONST: bool;
+                }
+                pub struct TestStruct {}
+                impl TestTrait for TestStruct {
+                    const CONST: bool = true;
+                }
+            }
+            ",
+            r"
+            use dep::test_mod::TestTrait;
+            fn main() {
+                dep::test_mod::TestStruct::CONST
+            }
+            ",
+        );
+    }
+    #[test]
+    fn assoc_fn_as_method_cross_crate() {
+        check_assist_not_applicable(
+            auto_import,
+            r"
+            //- /main.rs crate:main deps:dep
+            fn main() {
+                let test_struct = dep::test_mod::TestStruct {};
+                test_struct.test_func<|>tion()
+            }
+            //- /dep.rs crate:dep
+            pub mod test_mod {
+                pub trait TestTrait {
+                    fn test_function();
+                }
+                pub struct TestStruct {}
+                impl TestTrait for TestStruct {
+                    fn test_function() {}
+                }
+            }
+            ",
+        );
+    }
+    #[test]
+    fn private_trait_cross_crate() {
+        check_assist_not_applicable(
+            auto_import,
+            r"
+            //- /main.rs crate:main deps:dep
+            fn main() {
+                let test_struct = dep::test_mod::TestStruct {};
+                test_struct.test_meth<|>od()
+            }
+            //- /dep.rs crate:dep
+            pub mod test_mod {
+                trait TestTrait {
+                    fn test_method(&self);
+                }
+                pub struct TestStruct {}
+                impl TestTrait for TestStruct {
+                    fn test_method(&self) {}
+                }
+            }
+            ",
+        );
+    }
+    #[test]
    fn not_applicable_for_imported_trait_for_method() {
        check_assist_not_applicable(
            auto_import,
diff --git a/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs b/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
index bdf9d7ae2..ca19cf198 100644
--- a/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
+++ b/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
@@ -53,7 +53,7 @@ pub(crate) fn extract_struct_from_enum_variant(
        target,
        |builder| {
            let definition = Definition::ModuleDef(ModuleDef::EnumVariant(variant_hir));
-            let res = definition.find_usages(&ctx.db(), None);
+            let res = definition.find_usages(&ctx.sema, None);
            let start_offset = variant.parent_enum().syntax().text_range().start();
            let mut visited_modules_set = FxHashSet::default();
            visited_modules_set.insert(current_module);
diff --git a/crates/ra_assists/src/handlers/inline_local_variable.rs b/crates/ra_assists/src/handlers/inline_local_variable.rs
index f4fb0056b..259839535 100644
--- a/crates/ra_assists/src/handlers/inline_local_variable.rs
+++ b/crates/ra_assists/src/handlers/inline_local_variable.rs
@@ -44,7 +44,7 @@ pub(crate) fn inline_local_variable(acc: &mut Assists, ctx: &AssistContext) -> O
    let def = ctx.sema.to_def(&bind_pat)?;
    let def = Definition::Local(def);
-    let refs = def.find_usages(ctx.db(), None);
+    let refs = def.find_usages(&ctx.sema, None);
    if refs.is_empty() {
        mark::hit!(test_not_applicable_if_variable_unused);
        return None;
diff --git a/crates/ra_db/src/input.rs b/crates/ra_db/src/input.rs
index 445a1ee48..aaa492759 100644
--- a/crates/ra_db/src/input.rs
+++ b/crates/ra_db/src/input.rs
@@ -197,6 +197,23 @@ impl CrateGraph {
        self.arena.keys().copied()
    }
+    /// Returns an iterator over all transitive dependencies of the given crate.
+    pub fn transitive_deps(&self, of: CrateId) -> impl Iterator<Item = CrateId> + '_ {
+        let mut worklist = vec![of];
+        let mut deps = FxHashSet::default();
+        while let Some(krate) = worklist.pop() {
+            if !deps.insert(krate) {
+                continue;
+            }
+            worklist.extend(self[krate].dependencies.iter().map(|dep| dep.crate_id));
+        }
+        deps.remove(&of);
+        deps.into_iter()
+    }
    // FIXME: this only finds one crate with the given root; we could have multiple
    pub fn crate_id_for_crate_root(&self, file_id: FileId) -> Option<CrateId> {
        let (&crate_id, _) =
diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index e09eb77c2..1b3525011 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -1053,12 +1053,14 @@ pub struct ImplDef {
 impl ImplDef {
    pub fn all_in_crate(db: &dyn HirDatabase, krate: Crate) -> Vec<ImplDef> {
-        let impls = db.impls_in_crate(krate.id);
+        let inherent = db.inherent_impls_in_crate(krate.id);
-        impls.all_impls().map(Self::from).collect()
+        let trait_ = db.trait_impls_in_crate(krate.id);
+        inherent.all_impls().chain(trait_.all_impls()).map(Self::from).collect()
    }
    pub fn for_trait(db: &dyn HirDatabase, krate: Crate, trait_: Trait) -> Vec<ImplDef> {
-        let impls = db.impls_in_crate(krate.id);
+        let impls = db.trait_impls_in_crate(krate.id);
-        impls.lookup_impl_defs_for_trait(trait_.id).map(Self::from).collect()
+        impls.for_trait(trait_.id).map(Self::from).collect()
    }
    pub fn target_trait(self, db: &dyn HirDatabase) -> Option<TypeRef> {
@@ -1187,7 +1189,7 @@ impl Type {
            None => return false,
        };
-        let canonical_ty = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical_ty = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        method_resolution::implements_trait(
            &canonical_ty,
            db,
@@ -1211,7 +1213,7 @@ impl Type {
                self.ty.environment.clone(),
                hir_ty::Obligation::Trait(trait_ref),
            ),
-            num_vars: 0,
+            kinds: Arc::new([]),
        };
        db.trait_solve(self.krate, goal).is_some()
@@ -1286,7 +1288,7 @@ impl Type {
    pub fn autoderef<'a>(&'a self, db: &'a dyn HirDatabase) -> impl Iterator<Item = Type> + 'a {
        // There should be no inference vars in types passed here
        // FIXME check that?
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        let environment = self.ty.environment.clone();
        let ty = InEnvironment { value: canonical, environment };
        autoderef(db, Some(self.krate), ty)
@@ -1303,10 +1305,10 @@ impl Type {
        mut callback: impl FnMut(AssocItem) -> Option<T>,
    ) -> Option<T> {
        for krate in self.ty.value.def_crates(db, krate.id)? {
-            let impls = db.impls_in_crate(krate);
+            let impls = db.inherent_impls_in_crate(krate);
-            for impl_def in impls.lookup_impl_defs(&self.ty.value) {
+            for impl_def in impls.for_self_ty(&self.ty.value) {
-                for &item in db.impl_data(impl_def).items.iter() {
+                for &item in db.impl_data(*impl_def).items.iter() {
                    if let Some(result) = callback(item.into()) {
                        return Some(result);
                    }
@@ -1327,7 +1329,7 @@ impl Type {
        // There should be no inference vars in types passed here
        // FIXME check that?
        // FIXME replace Unknown by bound vars here
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        let env = self.ty.environment.clone();
        let krate = krate.id;
@@ -1358,7 +1360,7 @@ impl Type {
        // There should be no inference vars in types passed here
        // FIXME check that?
        // FIXME replace Unknown by bound vars here
-        let canonical = Canonical { value: self.ty.value.clone(), num_vars: 0 };
+        let canonical = Canonical { value: self.ty.value.clone(), kinds: Arc::new([]) };
        let env = self.ty.environment.clone();
        let krate = krate.id;
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index bb67952de..cb48ca065 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -16,10 +16,10 @@ pub use hir_expand::db::{
 pub use hir_ty::db::{
    AssociatedTyDataQuery, AssociatedTyValueQuery, CallableItemSignatureQuery, FieldTypesQuery,
    GenericDefaultsQuery, GenericPredicatesForParamQuery, GenericPredicatesQuery, HirDatabase,
-    HirDatabaseStorage, ImplDatumQuery, ImplSelfTyQuery, ImplTraitQuery, ImplsFromDepsQuery,
+    HirDatabaseStorage, ImplDatumQuery, ImplSelfTyQuery, ImplTraitQuery, InferQueryQuery,
-    ImplsInCrateQuery, InferQueryQuery, InternAssocTyValueQuery, InternChalkImplQuery,
+    InherentImplsInCrateQuery, InternAssocTyValueQuery, InternChalkImplQuery, InternTypeCtorQuery,
-    InternTypeCtorQuery, InternTypeParamIdQuery, ReturnTypeImplTraitsQuery, StructDatumQuery,
+    InternTypeParamIdQuery, ReturnTypeImplTraitsQuery, StructDatumQuery, TraitDatumQuery,
-    TraitDatumQuery, TraitSolveQuery, TyQuery, ValueTyQuery,
+    TraitImplsInCrateQuery, TraitImplsInDepsQuery, TraitSolveQuery, TyQuery, ValueTyQuery,
 };
 #[test]
diff --git a/crates/ra_hir_def/src/import_map.rs b/crates/ra_hir_def/src/import_map.rs
index 68e20d06b..869f3ca5a 100644
--- a/crates/ra_hir_def/src/import_map.rs
+++ b/crates/ra_hir_def/src/import_map.rs
@@ -5,14 +5,16 @@ use std::{cmp::Ordering, fmt, hash::BuildHasherDefault, sync::Arc};
 use fst::{self, Streamer};
 use indexmap::{map::Entry, IndexMap};
 use ra_db::CrateId;
-use rustc_hash::FxHasher;
+use ra_syntax::SmolStr;
+use rustc_hash::{FxHashMap, FxHasher};
+use smallvec::SmallVec;
 use crate::{
    db::DefDatabase,
    item_scope::ItemInNs,
    path::{ModPath, PathKind},
    visibility::Visibility,
-    ModuleDefId, ModuleId,
+    AssocItemId, ModuleDefId, ModuleId, TraitId,
 };
 type FxIndexMap<K, V> = IndexMap<K, V, BuildHasherDefault<FxHasher>>;
@@ -34,6 +36,7 @@ pub struct ImportInfo {
 ///
 /// Note that all paths are relative to the containing crate's root, so the crate name still needs
 /// to be prepended to the `ModPath` before the path is valid.
+#[derive(Default)]
 pub struct ImportMap {
    map: FxIndexMap<ItemInNs, ImportInfo>,
@@ -45,13 +48,17 @@ pub struct ImportMap {
    /// the index of the first one.
    importables: Vec<ItemInNs>,
    fst: fst::Map<Vec<u8>>,
+    /// Maps names of associated items to the item's ID. Only includes items whose defining trait is
+    /// exported.
+    assoc_map: FxHashMap<SmolStr, SmallVec<[AssocItemId; 1]>>,
 }
 impl ImportMap {
    pub fn import_map_query(db: &dyn DefDatabase, krate: CrateId) -> Arc<Self> {
        let _p = ra_prof::profile("import_map_query");
        let def_map = db.crate_def_map(krate);
-        let mut import_map = FxIndexMap::with_capacity_and_hasher(64, Default::default());
+        let mut import_map = Self::default();
        // We look only into modules that are public(ly reexported), starting with the crate root.
        let empty = ModPath { kind: PathKind::Plain, segments: vec![] };
@@ -85,7 +92,7 @@ impl ImportMap {
                for item in per_ns.iter_items() {
                    let path = mk_path();
-                    match import_map.entry(item) {
+                    match import_map.map.entry(item) {
                        Entry::Vacant(entry) => {
                            entry.insert(ImportInfo { path, container: module });
                        }
@@ -105,11 +112,16 @@ impl ImportMap {
                    if let Some(ModuleDefId::ModuleId(mod_id)) = item.as_module_def_id() {
                        worklist.push((mod_id, mk_path()));
                    }
+                    // If we've added a path to a trait, add the trait's methods to the method map.
+                    if let Some(ModuleDefId::TraitId(tr)) = item.as_module_def_id() {
+                        import_map.collect_trait_methods(db, tr);
+                    }
                }
            }
        }
-        let mut importables = import_map.iter().collect::<Vec<_>>();
+        let mut importables = import_map.map.iter().collect::<Vec<_>>();
        importables.sort_by(cmp);
@@ -133,10 +145,10 @@ impl ImportMap {
            builder.insert(key, start as u64).unwrap();
        }
-        let fst = fst::Map::new(builder.into_inner().unwrap()).unwrap();
+        import_map.fst = fst::Map::new(builder.into_inner().unwrap()).unwrap();
-        let importables = importables.iter().map(|(item, _)| **item).collect();
+        import_map.importables = importables.iter().map(|(item, _)| **item).collect();
-        Arc::new(Self { map: import_map, fst, importables })
+        Arc::new(import_map)
    }
    /// Returns the `ModPath` needed to import/mention `item`, relative to this crate's root.
@@ -147,6 +159,13 @@ impl ImportMap {
    pub fn import_info_for(&self, item: ItemInNs) -> Option<&ImportInfo> {
        self.map.get(&item)
    }
+    fn collect_trait_methods(&mut self, db: &dyn DefDatabase, tr: TraitId) {
+        let data = db.trait_data(tr);
+        for (name, item) in data.items.iter() {
+            self.assoc_map.entry(name.to_string().into()).or_default().push(*item);
+        }
+    }
 }
 impl PartialEq for ImportMap {
@@ -290,13 +309,26 @@ pub fn search_dependencies<'a>(
        }
    }
+    // Add all exported associated items whose names match the query (exactly).
+    for map in &import_maps {
+        if let Some(v) = map.assoc_map.get(&*query.query) {
+            res.extend(v.iter().map(|&assoc| {
+                ItemInNs::Types(match assoc {
+                    AssocItemId::FunctionId(it) => it.into(),
+                    AssocItemId::ConstId(it) => it.into(),
+                    AssocItemId::TypeAliasId(it) => it.into(),
+                })
+            }));
+        }
+    }
    res
 }
 #[cfg(test)]
 mod tests {
    use super::*;
-    use crate::test_db::TestDB;
+    use crate::{test_db::TestDB, AssocContainerId, Lookup};
    use insta::assert_snapshot;
    use itertools::Itertools;
    use ra_db::fixture::WithFixture;
@@ -339,6 +371,7 @@ mod tests {
                    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();
@@ -353,6 +386,29 @@ mod tests {
            .join("\n")
    }
+    fn assoc_to_trait(db: &dyn DefDatabase, item: ItemInNs) -> 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 item,
+        };
+        let container = match assoc {
+            AssocItemId::FunctionId(it) => it.lookup(db).container,
+            AssocItemId::ConstId(it) => it.lookup(db).container,
+            AssocItemId::TypeAliasId(it) => it.lookup(db).container,
+        };
+        match container {
+            AssocContainerId::TraitId(it) => ItemInNs::Types(it.into()),
+            _ => item,
+        }
+    }
    #[test]
    fn smoke() {
        let map = import_map(
@@ -610,6 +666,7 @@ mod tests {
        dep::Fmt (m)
        dep::fmt::Display (t)
        dep::format (v)
+        dep::fmt::Display (t)
        "###);
        let res = search_dependencies_of(ra_fixture, "main", Query::new("fmt").anchor_end());
@@ -618,6 +675,7 @@ mod tests {
        dep::Fmt (t)
        dep::Fmt (v)
        dep::Fmt (m)
+        dep::fmt::Display (t)
        "###);
    }
diff --git a/crates/ra_hir_def/src/item_tree/lower.rs b/crates/ra_hir_def/src/item_tree/lower.rs
index 5149dd141..06743d7fc 100644
--- a/crates/ra_hir_def/src/item_tree/lower.rs
+++ b/crates/ra_hir_def/src/item_tree/lower.rs
@@ -211,7 +211,7 @@ impl Ctx {
    fn lower_record_field(&mut self, field: &ast::RecordFieldDef) -> Option<Field> {
        let name = field.name()?.as_name();
        let visibility = self.lower_visibility(field);
-        let type_ref = self.lower_type_ref(&field.ascribed_type()?);
+        let type_ref = self.lower_type_ref_opt(field.ascribed_type());
        let res = Field { name, type_ref, visibility };
        Some(res)
    }
diff --git a/crates/ra_hir_ty/src/autoderef.rs b/crates/ra_hir_ty/src/autoderef.rs
index 1b0f84c5c..c727012c6 100644
--- a/crates/ra_hir_ty/src/autoderef.rs
+++ b/crates/ra_hir_ty/src/autoderef.rs
@@ -37,7 +37,7 @@ pub(crate) fn deref(
    ty: InEnvironment<&Canonical<Ty>>,
 ) -> Option<Canonical<Ty>> {
    if let Some(derefed) = ty.value.value.builtin_deref() {
-        Some(Canonical { value: derefed, num_vars: ty.value.num_vars })
+        Some(Canonical { value: derefed, kinds: ty.value.kinds.clone() })
    } else {
        deref_by_trait(db, krate, ty)
    }
@@ -68,8 +68,8 @@ fn deref_by_trait(
    // Check that the type implements Deref at all
    let trait_ref = TraitRef { trait_: deref_trait, substs: parameters.clone() };
-    let implements_goal = super::Canonical {
+    let implements_goal = Canonical {
-        num_vars: ty.value.num_vars,
+        kinds: ty.value.kinds.clone(),
        value: InEnvironment {
            value: Obligation::Trait(trait_ref),
            environment: ty.environment.clone(),
@@ -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.num_vars)),
+        ty: Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, ty.value.kinds.len())),
        projection_ty: super::ProjectionTy { associated_ty: target, parameters },
    };
@@ -89,7 +89,8 @@ fn deref_by_trait(
    let in_env = InEnvironment { value: obligation, environment: ty.environment };
-    let canonical = super::Canonical { num_vars: 1 + ty.value.num_vars, value: in_env };
+    let canonical =
+        Canonical::new(in_env, ty.value.kinds.iter().copied().chain(Some(super::TyKind::General)));
    let solution = db.trait_solve(krate, canonical)?;
@@ -110,7 +111,7 @@ fn deref_by_trait(
            // assumptions will be broken. We would need to properly introduce
            // new variables in that case
-            for i in 1..vars.0.num_vars {
+            for i in 1..vars.0.kinds.len() {
                if vars.0.value[i - 1] != Ty::Bound(BoundVar::new(DebruijnIndex::INNERMOST, i - 1))
                {
                    warn!("complex solution for derefing {:?}: {:?}, ignoring", ty.value, solution);
@@ -119,7 +120,7 @@ fn deref_by_trait(
            }
            Some(Canonical {
                value: vars.0.value[vars.0.value.len() - 1].clone(),
-                num_vars: vars.0.num_vars,
+                kinds: vars.0.kinds.clone(),
            })
        }
        Solution::Ambig(_) => {
diff --git a/crates/ra_hir_ty/src/db.rs b/crates/ra_hir_ty/src/db.rs
index cad553273..dc06c0ee7 100644
--- a/crates/ra_hir_ty/src/db.rs
+++ b/crates/ra_hir_ty/src/db.rs
@@ -11,7 +11,7 @@ use ra_db::{impl_intern_key, salsa, CrateId, Upcast};
 use ra_prof::profile;
 use crate::{
-    method_resolution::CrateImplDefs,
+    method_resolution::{InherentImpls, TraitImpls},
    traits::{chalk, AssocTyValue, Impl},
    Binders, CallableDef, GenericPredicate, InferenceResult, OpaqueTyId, PolyFnSig,
    ReturnTypeImplTraits, TraitRef, Ty, TyDefId, TypeCtor, ValueTyDefId,
@@ -67,11 +67,14 @@ pub trait HirDatabase: DefDatabase + Upcast<dyn DefDatabase> {
    #[salsa::invoke(crate::lower::generic_defaults_query)]
    fn generic_defaults(&self, def: GenericDefId) -> Arc<[Binders<Ty>]>;
-    #[salsa::invoke(crate::method_resolution::CrateImplDefs::impls_in_crate_query)]
+    #[salsa::invoke(InherentImpls::inherent_impls_in_crate_query)]
-    fn impls_in_crate(&self, krate: CrateId) -> Arc<CrateImplDefs>;
+    fn inherent_impls_in_crate(&self, krate: CrateId) -> Arc<InherentImpls>;
-    #[salsa::invoke(crate::method_resolution::CrateImplDefs::impls_from_deps_query)]
+    #[salsa::invoke(TraitImpls::trait_impls_in_crate_query)]
-    fn impls_from_deps(&self, krate: CrateId) -> Arc<CrateImplDefs>;
+    fn trait_impls_in_crate(&self, krate: CrateId) -> Arc<TraitImpls>;
+    #[salsa::invoke(TraitImpls::trait_impls_in_deps_query)]
+    fn trait_impls_in_deps(&self, krate: CrateId) -> Arc<TraitImpls>;
    // Interned IDs for Chalk integration
    #[salsa::interned]
diff --git a/crates/ra_hir_ty/src/infer/unify.rs b/crates/ra_hir_ty/src/infer/unify.rs
index 269495ca0..2e895d911 100644
--- a/crates/ra_hir_ty/src/infer/unify.rs
+++ b/crates/ra_hir_ty/src/infer/unify.rs
@@ -9,7 +9,7 @@ use test_utils::mark;
 use super::{InferenceContext, Obligation};
 use crate::{
    BoundVar, Canonical, DebruijnIndex, GenericPredicate, InEnvironment, InferTy, Substs, Ty,
-    TypeCtor, TypeWalk,
+    TyKind, TypeCtor, TypeWalk,
 };
 impl<'a> InferenceContext<'a> {
@@ -86,10 +86,20 @@ where
    }
    fn into_canonicalized<T>(self, result: T) -> Canonicalized<T> {
-        Canonicalized {
+        let kinds = self
-            value: Canonical { value: result, num_vars: self.free_vars.len() },
+            .free_vars
-            free_vars: self.free_vars,
+            .iter()
-        }
+            .map(|v| match v {
+                // mapping MaybeNeverTypeVar to the same kind as general ones
+                // should be fine, because as opposed to int or float type vars,
+                // they don't restrict what kind of type can go into them, they
+                // just affect fallback.
+                InferTy::TypeVar(_) | InferTy::MaybeNeverTypeVar(_) => TyKind::General,
+                InferTy::IntVar(_) => TyKind::Integer,
+                InferTy::FloatVar(_) => TyKind::Float,
+            })
+            .collect();
+        Canonicalized { value: Canonical { value: result, kinds }, free_vars: self.free_vars }
    }
    pub(crate) fn canonicalize_ty(mut self, ty: Ty) -> Canonicalized<Ty> {
@@ -131,26 +141,41 @@ impl<T> Canonicalized<T> {
        ty
    }
-    pub fn apply_solution(&self, ctx: &mut InferenceContext<'_>, solution: Canonical<Vec<Ty>>) {
+    pub fn apply_solution(&self, ctx: &mut InferenceContext<'_>, solution: Canonical<Substs>) {
        // the solution may contain new variables, which we need to convert to new inference vars
-        let new_vars = Substs((0..solution.num_vars).map(|_| ctx.table.new_type_var()).collect());
+        let new_vars = Substs(
+            solution
+                .kinds
+                .iter()
+                .map(|k| match k {
+                    TyKind::General => ctx.table.new_type_var(),
+                    TyKind::Integer => ctx.table.new_integer_var(),
+                    TyKind::Float => ctx.table.new_float_var(),
+                })
+                .collect(),
+        );
        for (i, ty) in solution.value.into_iter().enumerate() {
            let var = self.free_vars[i];
            // eagerly replace projections in the type; we may be getting types
            // e.g. from where clauses where this hasn't happened yet
-            let ty = ctx.normalize_associated_types_in(ty.subst_bound_vars(&new_vars));
+            let ty = ctx.normalize_associated_types_in(ty.clone().subst_bound_vars(&new_vars));
            ctx.table.unify(&Ty::Infer(var), &ty);
        }
    }
 }
-pub fn unify(ty1: &Canonical<Ty>, ty2: &Canonical<Ty>) -> Option<Substs> {
+pub fn unify(tys: &Canonical<(Ty, Ty)>) -> Option<Substs> {
    let mut table = InferenceTable::new();
-    let num_vars = ty1.num_vars.max(ty2.num_vars);
+    let vars = Substs(
-    let vars =
+        tys.kinds
-        Substs::builder(num_vars).fill(std::iter::repeat_with(|| table.new_type_var())).build();
+            .iter()
-    let ty1_with_vars = ty1.value.clone().subst_bound_vars(&vars);
+            // we always use type vars here because we want everything to
-    let ty2_with_vars = ty2.value.clone().subst_bound_vars(&vars);
+            // fallback to Unknown in the end (kind of hacky, as below)
+            .map(|_| table.new_type_var())
+            .collect(),
+    );
+    let ty1_with_vars = tys.value.0.clone().subst_bound_vars(&vars);
+    let ty2_with_vars = tys.value.1.clone().subst_bound_vars(&vars);
    if !table.unify(&ty1_with_vars, &ty2_with_vars) {
        return None;
    }
@@ -162,7 +187,7 @@ pub fn unify(ty1: &Canonical<Ty>, ty2: &Canonical<Ty>) -> Option<Substs> {
        }
    }
    Some(
-        Substs::builder(ty1.num_vars)
+        Substs::builder(tys.kinds.len())
            .fill(vars.iter().map(|v| table.resolve_ty_completely(v.clone())))
            .build(),
    )
diff --git a/crates/ra_hir_ty/src/lib.rs b/crates/ra_hir_ty/src/lib.rs
index c9513b752..7f3f5e771 100644
--- a/crates/ra_hir_ty/src/lib.rs
+++ b/crates/ra_hir_ty/src/lib.rs
@@ -662,13 +662,27 @@ impl TypeWalk for GenericPredicate {
 /// Basically a claim (currently not validated / checked) that the contained
 /// type / trait ref contains no inference variables; any inference variables it
-/// contained have been replaced by bound variables, and `num_vars` tells us how
+/// contained have been replaced by bound variables, and `kinds` tells us how
-/// many there are. This is used to erase irrelevant differences between types
+/// many there are and whether they were normal or float/int variables. This is
-/// before using them in queries.
+/// used to erase irrelevant differences between types before using them in
+/// queries.
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct Canonical<T> {
    pub value: T,
-    pub num_vars: usize,
+    pub kinds: Arc<[TyKind]>,
+}
+impl<T> Canonical<T> {
+    pub fn new(value: T, kinds: impl IntoIterator<Item = TyKind>) -> Self {
+        Self { value, kinds: kinds.into_iter().collect() }
+    }
+}
+#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
+pub enum TyKind {
+    General,
+    Integer,
+    Float,
 }
 /// A function signature as seen by type inference: Several parameter types and
diff --git a/crates/ra_hir_ty/src/method_resolution.rs b/crates/ra_hir_ty/src/method_resolution.rs
index c19519cf1..a45febbf7 100644
--- a/crates/ra_hir_ty/src/method_resolution.rs
+++ b/crates/ra_hir_ty/src/method_resolution.rs
@@ -2,7 +2,7 @@
 //! For details about how this works in rustc, see the method lookup page in the
 //! [rustc guide](https://rust-lang.github.io/rustc-guide/method-lookup.html)
 //! and the corresponding code mostly in librustc_typeck/check/method/probe.rs.
-use std::sync::Arc;
+use std::{iter, sync::Arc};
 use arrayvec::ArrayVec;
 use hir_def::{
@@ -17,7 +17,8 @@ use rustc_hash::{FxHashMap, FxHashSet};
 use super::Substs;
 use crate::{
    autoderef, db::HirDatabase, primitive::FloatBitness, utils::all_super_traits, ApplicationTy,
-    Canonical, DebruijnIndex, InEnvironment, TraitEnvironment, TraitRef, Ty, TypeCtor, TypeWalk,
+    Canonical, DebruijnIndex, InEnvironment, TraitEnvironment, TraitRef, Ty, TyKind, TypeCtor,
+    TypeWalk,
 };
 /// This is used as a key for indexing impls.
@@ -38,136 +39,131 @@ impl TyFingerprint {
    }
 }
-/// A queryable and mergeable collection of impls.
+/// Trait impls defined or available in some crate.
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Debug, Eq, PartialEq)]
-pub struct CrateImplDefs {
+pub struct TraitImpls {
-    inherent_impls: FxHashMap<TyFingerprint, Vec<ImplId>>,
+    // If the `Option<TyFingerprint>` is `None`, the impl may apply to any self type.
-    impls_by_trait: FxHashMap<TraitId, FxHashMap<Option<TyFingerprint>, Vec<ImplId>>>,
+    map: FxHashMap<TraitId, FxHashMap<Option<TyFingerprint>, Vec<ImplId>>>,
 }
-impl CrateImplDefs {
+impl TraitImpls {
-    pub(crate) fn impls_in_crate_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<CrateImplDefs> {
+    pub(crate) fn trait_impls_in_crate_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<Self> {
-        let _p = profile("impls_in_crate_query");
+        let _p = profile("trait_impls_in_crate_query");
-        let mut res = CrateImplDefs {
+        let mut impls = Self { map: FxHashMap::default() };
-            inherent_impls: FxHashMap::default(),
-            impls_by_trait: FxHashMap::default(),
-        };
-        res.fill(db, krate);
-        Arc::new(res)
+        let crate_def_map = db.crate_def_map(krate);
+        for (_module_id, module_data) in crate_def_map.modules.iter() {
+            for impl_id in module_data.scope.impls() {
+                let target_trait = match db.impl_trait(impl_id) {
+                    Some(tr) => tr.value.trait_,
+                    None => continue,
+                };
+                let self_ty = db.impl_self_ty(impl_id);
+                let self_ty_fp = TyFingerprint::for_impl(&self_ty.value);
+                impls
+                    .map
+                    .entry(target_trait)
+                    .or_default()
+                    .entry(self_ty_fp)
+                    .or_default()
+                    .push(impl_id);
+            }
+        }
+        Arc::new(impls)
    }
-    /// Collects all impls from transitive dependencies of `krate` that may be used by `krate`.
+    pub(crate) fn trait_impls_in_deps_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<Self> {
-    ///
+        let _p = profile("trait_impls_in_deps_query");
-    /// The full set of impls that can be used by `krate` is the returned map plus all the impls
-    /// from `krate` itself.
-    pub(crate) fn impls_from_deps_query(
-        db: &dyn HirDatabase,
-        krate: CrateId,
-    ) -> Arc<CrateImplDefs> {
-        let _p = profile("impls_from_deps_query");
        let crate_graph = db.crate_graph();
-        let mut res = CrateImplDefs {
+        let mut res = Self { map: FxHashMap::default() };
-            inherent_impls: FxHashMap::default(),
-            impls_by_trait: FxHashMap::default(),
-        };
-        // For each dependency, calculate `impls_from_deps` recursively, then add its own
+        for krate in crate_graph.transitive_deps(krate) {
-        // `impls_in_crate`.
+            res.merge(&db.trait_impls_in_crate(krate));
-        // As we might visit crates multiple times, `merge` has to deduplicate impls to avoid
-        // wasting memory.
-        for dep in &crate_graph[krate].dependencies {
-            res.merge(&db.impls_from_deps(dep.crate_id));
-            res.merge(&db.impls_in_crate(dep.crate_id));
        }
        Arc::new(res)
    }
-    fn fill(&mut self, db: &dyn HirDatabase, krate: CrateId) {
-        let crate_def_map = db.crate_def_map(krate);
-        for (_module_id, module_data) in crate_def_map.modules.iter() {
-            for impl_id in module_data.scope.impls() {
-                match db.impl_trait(impl_id) {
-                    Some(tr) => {
-                        let self_ty = db.impl_self_ty(impl_id);
-                        let self_ty_fp = TyFingerprint::for_impl(&self_ty.value);
-                        self.impls_by_trait
-                            .entry(tr.value.trait_)
-                            .or_default()
-                            .entry(self_ty_fp)
-                            .or_default()
-                            .push(impl_id);
-                    }
-                    None => {
-                        let self_ty = db.impl_self_ty(impl_id);
-                        if let Some(self_ty_fp) = TyFingerprint::for_impl(&self_ty.value) {
-                            self.inherent_impls.entry(self_ty_fp).or_default().push(impl_id);
-                        }
-                    }
-                }
-            }
-        }
-    }
    fn merge(&mut self, other: &Self) {
-        for (fp, impls) in &other.inherent_impls {
+        for (trait_, other_map) in &other.map {
-            let vec = self.inherent_impls.entry(*fp).or_default();
+            let map = self.map.entry(*trait_).or_default();
-            vec.extend(impls);
-            vec.sort();
-            vec.dedup();
-        }
-        for (trait_, other_map) in &other.impls_by_trait {
-            let map = self.impls_by_trait.entry(*trait_).or_default();
            for (fp, impls) in other_map {
                let vec = map.entry(*fp).or_default();
                vec.extend(impls);
-                vec.sort();
-                vec.dedup();
            }
        }
    }
-    pub fn lookup_impl_defs(&self, ty: &Ty) -> impl Iterator<Item = ImplId> + '_ {
+    /// Queries all impls of the given trait.
-        let fingerprint = TyFingerprint::for_impl(ty);
+    pub fn for_trait(&self, trait_: TraitId) -> impl Iterator<Item = ImplId> + '_ {
-        fingerprint.and_then(|f| self.inherent_impls.get(&f)).into_iter().flatten().copied()
+        self.map
-    }
+            .get(&trait_)
-    pub fn lookup_impl_defs_for_trait(&self, tr: TraitId) -> impl Iterator<Item = ImplId> + '_ {
-        self.impls_by_trait
-            .get(&tr)
            .into_iter()
-            .flat_map(|m| m.values().flat_map(|v| v.iter().copied()))
+            .flat_map(|map| map.values().flat_map(|v| v.iter().copied()))
    }
-    pub fn lookup_impl_defs_for_trait_and_ty(
+    /// Queries all impls of `trait_` that may apply to `self_ty`.
+    pub fn for_trait_and_self_ty(
        &self,
-        tr: TraitId,
+        trait_: TraitId,
-        fp: TyFingerprint,
+        self_ty: TyFingerprint,
    ) -> impl Iterator<Item = ImplId> + '_ {
-        self.impls_by_trait
+        self.map
-            .get(&tr)
+            .get(&trait_)
-            .and_then(|m| m.get(&Some(fp)))
            .into_iter()
-            .flatten()
+            .flat_map(move |map| map.get(&None).into_iter().chain(map.get(&Some(self_ty))))
-            .copied()
+            .flat_map(|v| v.iter().copied())
-            .chain(
+    }
-                self.impls_by_trait
-                    .get(&tr)
+    pub fn all_impls(&self) -> impl Iterator<Item = ImplId> + '_ {
-                    .and_then(|m| m.get(&None))
+        self.map.values().flat_map(|map| map.values().flat_map(|v| v.iter().copied()))
-                    .into_iter()
+    }
-                    .flatten()
+}
-                    .copied(),
-            )
+/// Inherent impls defined in some crate.
+///
+/// Inherent impls can only be defined in the crate that also defines the self type of the impl
+/// (note that some primitives are considered to be defined by both libcore and liballoc).
+///
+/// This makes inherent impl lookup easier than trait impl lookup since we only have to consider a
+/// single crate.
+#[derive(Debug, Eq, PartialEq)]
+pub struct InherentImpls {
+    map: FxHashMap<TyFingerprint, Vec<ImplId>>,
+}
+impl InherentImpls {
+    pub(crate) fn inherent_impls_in_crate_query(db: &dyn HirDatabase, krate: CrateId) -> Arc<Self> {
+        let mut map: FxHashMap<_, Vec<_>> = FxHashMap::default();
+        let crate_def_map = db.crate_def_map(krate);
+        for (_module_id, module_data) in crate_def_map.modules.iter() {
+            for impl_id in module_data.scope.impls() {
+                let data = db.impl_data(impl_id);
+                if data.target_trait.is_some() {
+                    continue;
+                }
+                let self_ty = db.impl_self_ty(impl_id);
+                if let Some(fp) = TyFingerprint::for_impl(&self_ty.value) {
+                    map.entry(fp).or_default().push(impl_id);
+                }
+            }
+        }
+        Arc::new(Self { map })
+    }
+    pub fn for_self_ty(&self, self_ty: &Ty) -> &[ImplId] {
+        match TyFingerprint::for_impl(self_ty) {
+            Some(fp) => self.map.get(&fp).map(|vec| vec.as_ref()).unwrap_or(&[]),
+            None => &[],
+        }
    }
-    pub fn all_impls<'a>(&'a self) -> impl Iterator<Item = ImplId> + 'a {
+    pub fn all_impls(&self) -> impl Iterator<Item = ImplId> + '_ {
-        self.inherent_impls
+        self.map.values().flat_map(|v| v.iter().copied())
-            .values()
-            .chain(self.impls_by_trait.values().flat_map(|m| m.values()))
-            .flatten()
-            .copied()
    }
 }
@@ -377,7 +373,7 @@ fn iterate_method_candidates_with_autoref(
        return true;
    }
    let refed = Canonical {
-        num_vars: deref_chain[0].num_vars,
+        kinds: deref_chain[0].kinds.clone(),
        value: Ty::apply_one(TypeCtor::Ref(Mutability::Shared), deref_chain[0].value.clone()),
    };
    if iterate_method_candidates_by_receiver(
@@ -393,7 +389,7 @@ fn iterate_method_candidates_with_autoref(
        return true;
    }
    let ref_muted = Canonical {
-        num_vars: deref_chain[0].num_vars,
+        kinds: deref_chain[0].kinds.clone(),
        value: Ty::apply_one(TypeCtor::Ref(Mutability::Mut), deref_chain[0].value.clone()),
    };
    if iterate_method_candidates_by_receiver(
@@ -524,9 +520,9 @@ fn iterate_inherent_methods(
        None => return false,
    };
    for krate in def_crates {
-        let impls = db.impls_in_crate(krate);
+        let impls = db.inherent_impls_in_crate(krate);
-        for impl_def in impls.lookup_impl_defs(&self_ty.value) {
+        for &impl_def in impls.for_self_ty(&self_ty.value) {
            for &item in db.impl_data(impl_def).items.iter() {
                if !is_valid_candidate(db, name, receiver_ty, item, self_ty) {
                    continue;
@@ -612,18 +608,19 @@ pub(crate) fn inherent_impl_substs(
    // we create a var for each type parameter of the impl; we need to keep in
    // mind here that `self_ty` might have vars of its own
    let vars = Substs::build_for_def(db, impl_id)
-        .fill_with_bound_vars(DebruijnIndex::INNERMOST, self_ty.num_vars)
+        .fill_with_bound_vars(DebruijnIndex::INNERMOST, self_ty.kinds.len())
        .build();
    let self_ty_with_vars = db.impl_self_ty(impl_id).subst(&vars);
-    let self_ty_with_vars =
+    let mut kinds = self_ty.kinds.to_vec();
-        Canonical { num_vars: vars.len() + self_ty.num_vars, value: self_ty_with_vars };
+    kinds.extend(iter::repeat(TyKind::General).take(vars.len()));
-    let substs = super::infer::unify(&self_ty_with_vars, self_ty);
+    let tys = Canonical { kinds: kinds.into(), value: (self_ty_with_vars, self_ty.value.clone()) };
+    let substs = super::infer::unify(&tys);
    // We only want the substs for the vars we added, not the ones from self_ty.
    // Also, if any of the vars we added are still in there, we replace them by
    // Unknown. I think this can only really happen if self_ty contained
    // Unknown, and in that case we want the result to contain Unknown in those
    // places again.
-    substs.map(|s| fallback_bound_vars(s.suffix(vars.len()), self_ty.num_vars))
+    substs.map(|s| fallback_bound_vars(s.suffix(vars.len()), self_ty.kinds.len()))
 }
 /// This replaces any 'free' Bound vars in `s` (i.e. those with indices past
@@ -683,15 +680,15 @@ fn generic_implements_goal(
    trait_: TraitId,
    self_ty: Canonical<Ty>,
 ) -> Canonical<InEnvironment<super::Obligation>> {
-    let num_vars = self_ty.num_vars;
+    let mut kinds = self_ty.kinds.to_vec();
    let substs = super::Substs::build_for_def(db, trait_)
        .push(self_ty.value)
-        .fill_with_bound_vars(DebruijnIndex::INNERMOST, num_vars)
+        .fill_with_bound_vars(DebruijnIndex::INNERMOST, kinds.len())
        .build();
-    let num_vars = substs.len() - 1 + self_ty.num_vars;
+    kinds.extend(iter::repeat(TyKind::General).take(substs.len() - 1));
    let trait_ref = TraitRef { trait_, substs };
    let obligation = super::Obligation::Trait(trait_ref);
-    Canonical { num_vars, value: InEnvironment::new(env, obligation) }
+    Canonical { kinds: kinds.into(), value: InEnvironment::new(env, obligation) }
 }
 fn autoderef_method_receiver(
@@ -704,9 +701,9 @@ fn autoderef_method_receiver(
    if let Some(Ty::Apply(ApplicationTy { ctor: TypeCtor::Array, parameters })) =
        deref_chain.last().map(|ty| &ty.value)
    {
-        let num_vars = deref_chain.last().unwrap().num_vars;
+        let kinds = deref_chain.last().unwrap().kinds.clone();
        let unsized_ty = Ty::apply(TypeCtor::Slice, parameters.clone());
-        deref_chain.push(Canonical { value: unsized_ty, num_vars })
+        deref_chain.push(Canonical { value: unsized_ty, kinds })
    }
    deref_chain
 }
diff --git a/crates/ra_hir_ty/src/tests.rs b/crates/ra_hir_ty/src/tests.rs
index 9084c3bed..eeac34d14 100644
--- a/crates/ra_hir_ty/src/tests.rs
+++ b/crates/ra_hir_ty/src/tests.rs
@@ -508,6 +508,30 @@ fn no_such_field_with_feature_flag_diagnostics_on_struct_fields() {
 }
 #[test]
+fn no_such_field_with_type_macro() {
+    let diagnostics = TestDB::with_files(
+        r"
+        macro_rules! Type {
+            () => { u32 };
+        }
+        struct Foo {
+            bar: Type![],
+        }
+        impl Foo {
+            fn new() -> Self {
+                Foo { bar: 0 }
+            }
+        }
+        ",
+    )
+    .diagnostics()
+    .0;
+    assert_snapshot!(diagnostics, @r###""###);
+}
+#[test]
 fn missing_record_pat_field_diagnostic() {
    let diagnostics = TestDB::with_files(
        r"
diff --git a/crates/ra_hir_ty/src/tests/traits.rs b/crates/ra_hir_ty/src/tests/traits.rs
index 01c919a7e..766790576 100644
--- a/crates/ra_hir_ty/src/tests/traits.rs
+++ b/crates/ra_hir_ty/src/tests/traits.rs
@@ -3029,3 +3029,21 @@ fn infer_dyn_fn_output() {
    "###
    );
 }
+#[test]
+fn variable_kinds() {
+    check_types(
+        r#"
+trait Trait<T> { fn get(self, t: T) -> T; }
+struct S;
+impl Trait<u128> for S {}
+impl Trait<f32> for S {}
+fn test() {
+    S.get(1);
+  //^^^^^^^^ u128
+    S.get(1.);
+  //^^^^^^^^ f32
+}
+        "#,
+    );
+}
diff --git a/crates/ra_hir_ty/src/traits.rs b/crates/ra_hir_ty/src/traits.rs
index 6f43c3a22..2a6d7faef 100644
--- a/crates/ra_hir_ty/src/traits.rs
+++ b/crates/ra_hir_ty/src/traits.rs
@@ -1,5 +1,5 @@
 //! Trait solving using Chalk.
-use std::{panic, sync::Arc};
+use std::sync::Arc;
 use chalk_ir::cast::Cast;
 use hir_def::{
@@ -8,7 +8,7 @@ use hir_def::{
 use ra_db::{impl_intern_key, salsa, CrateId};
 use ra_prof::profile;
-use crate::{db::HirDatabase, DebruijnIndex};
+use crate::{db::HirDatabase, DebruijnIndex, Substs};
 use super::{Canonical, GenericPredicate, HirDisplay, ProjectionTy, TraitRef, Ty, TypeWalk};
@@ -190,15 +190,7 @@ fn solution_from_chalk(
    solution: chalk_solve::Solution<Interner>,
 ) -> Solution {
    let convert_subst = |subst: chalk_ir::Canonical<chalk_ir::Substitution<Interner>>| {
-        let value = subst
+        let result = from_chalk(db, subst);
-            .value
-            .iter(&Interner)
-            .map(|p| match p.ty(&Interner) {
-                Some(ty) => from_chalk(db, ty.clone()),
-                None => unimplemented!(),
-            })
-            .collect();
-        let result = Canonical { value, num_vars: subst.binders.len(&Interner) };
        SolutionVariables(result)
    };
    match solution {
@@ -222,7 +214,7 @@ fn solution_from_chalk(
 }
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub struct SolutionVariables(pub Canonical<Vec<Ty>>);
+pub struct SolutionVariables(pub Canonical<Substs>);
 #[derive(Clone, Debug, PartialEq, Eq)]
 /// A (possible) solution for a proposed goal.
diff --git a/crates/ra_hir_ty/src/traits/chalk.rs b/crates/ra_hir_ty/src/traits/chalk.rs
index 8ef4941c0..c97b81d57 100644
--- a/crates/ra_hir_ty/src/traits/chalk.rs
+++ b/crates/ra_hir_ty/src/traits/chalk.rs
@@ -77,8 +77,8 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
        // Note: Since we're using impls_for_trait, only impls where the trait
        // can be resolved should ever reach Chalk. `impl_datum` relies on that
        // and will panic if the trait can't be resolved.
-        let in_deps = self.db.impls_from_deps(self.krate);
+        let in_deps = self.db.trait_impls_in_deps(self.krate);
-        let in_self = self.db.impls_in_crate(self.krate);
+        let in_self = self.db.trait_impls_in_crate(self.krate);
        let impl_maps = [in_deps, in_self];
        let id_to_chalk = |id: hir_def::ImplId| Impl::ImplDef(id).to_chalk(self.db);
@@ -87,14 +87,12 @@ impl<'a> chalk_solve::RustIrDatabase<Interner> for ChalkContext<'a> {
            Some(fp) => impl_maps
                .iter()
                .flat_map(|crate_impl_defs| {
-                    crate_impl_defs.lookup_impl_defs_for_trait_and_ty(trait_, fp).map(id_to_chalk)
+                    crate_impl_defs.for_trait_and_self_ty(trait_, fp).map(id_to_chalk)
                })
                .collect(),
            None => impl_maps
                .iter()
-                .flat_map(|crate_impl_defs| {
+                .flat_map(|crate_impl_defs| crate_impl_defs.for_trait(trait_).map(id_to_chalk))
-                    crate_impl_defs.lookup_impl_defs_for_trait(trait_).map(id_to_chalk)
-                })
                .collect(),
        };
diff --git a/crates/ra_hir_ty/src/traits/chalk/mapping.rs b/crates/ra_hir_ty/src/traits/chalk/mapping.rs
index ac82ea831..433d6aa03 100644
--- a/crates/ra_hir_ty/src/traits/chalk/mapping.rs
+++ b/crates/ra_hir_ty/src/traits/chalk/mapping.rs
@@ -17,7 +17,7 @@ use crate::{
    primitive::{FloatBitness, FloatTy, IntBitness, IntTy, Signedness},
    traits::{builtin, AssocTyValue, Canonical, Impl, Obligation},
    ApplicationTy, CallableDef, GenericPredicate, InEnvironment, OpaqueTy, OpaqueTyId,
-    ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, TraitRef, Ty, TypeCtor,
+    ProjectionPredicate, ProjectionTy, Substs, TraitEnvironment, TraitRef, Ty, TyKind, TypeCtor,
 };
 use super::interner::*;
@@ -555,22 +555,39 @@ where
    type Chalk = chalk_ir::Canonical<T::Chalk>;
    fn to_chalk(self, db: &dyn HirDatabase) -> chalk_ir::Canonical<T::Chalk> {
-        let parameter = chalk_ir::CanonicalVarKind::new(
+        let kinds = self
-            chalk_ir::VariableKind::Ty(chalk_ir::TyKind::General),
+            .kinds
-            chalk_ir::UniverseIndex::ROOT,
+            .iter()
-        );
+            .map(|k| match k {
+                TyKind::General => chalk_ir::TyKind::General,
+                TyKind::Integer => chalk_ir::TyKind::Integer,
+                TyKind::Float => chalk_ir::TyKind::Float,
+            })
+            .map(|tk| {
+                chalk_ir::CanonicalVarKind::new(
+                    chalk_ir::VariableKind::Ty(tk),
+                    chalk_ir::UniverseIndex::ROOT,
+                )
+            });
        let value = self.value.to_chalk(db);
-        chalk_ir::Canonical {
+        chalk_ir::Canonical { value, binders: chalk_ir::CanonicalVarKinds::from(&Interner, kinds) }
-            value,
-            binders: chalk_ir::CanonicalVarKinds::from(&Interner, vec![parameter; self.num_vars]),
-        }
    }
    fn from_chalk(db: &dyn HirDatabase, canonical: chalk_ir::Canonical<T::Chalk>) -> Canonical<T> {
-        Canonical {
+        let kinds = canonical
-            num_vars: canonical.binders.len(&Interner),
+            .binders
-            value: from_chalk(db, canonical.value),
+            .iter(&Interner)
-        }
+            .map(|k| match k.kind {
+                chalk_ir::VariableKind::Ty(tk) => match tk {
+                    chalk_ir::TyKind::General => TyKind::General,
+                    chalk_ir::TyKind::Integer => TyKind::Integer,
+                    chalk_ir::TyKind::Float => TyKind::Float,
+                },
+                chalk_ir::VariableKind::Lifetime => panic!("unexpected lifetime from Chalk"),
+                chalk_ir::VariableKind::Const(_) => panic!("unexpected const from Chalk"),
+            })
+            .collect();
+        Canonical { kinds, value: from_chalk(db, canonical.value) }
    }
 }
diff --git a/crates/ra_ide/src/call_hierarchy.rs b/crates/ra_ide/src/call_hierarchy.rs
index bd0e48834..884353808 100644
--- a/crates/ra_ide/src/call_hierarchy.rs
+++ b/crates/ra_ide/src/call_hierarchy.rs
@@ -39,10 +39,11 @@ pub(crate) fn call_hierarchy(
 pub(crate) fn incoming_calls(db: &RootDatabase, position: FilePosition) -> Option<Vec<CallItem>> {
    let sema = Semantics::new(db);
    // 1. Find all refs
    // 2. Loop through refs and determine unique fndef. This will become our `from: CallHierarchyItem,` in the reply.
    // 3. Add ranges relative to the start of the fndef.
-    let refs = references::find_all_refs(db, position, None)?;
+    let refs = references::find_all_refs(&sema, position, None)?;
    let mut calls = CallLocations::default();
diff --git a/crates/ra_ide/src/completion.rs b/crates/ra_ide/src/completion.rs
index e1fcf379d..9ebb8ebb7 100644
--- a/crates/ra_ide/src/completion.rs
+++ b/crates/ra_ide/src/completion.rs
@@ -63,11 +63,11 @@ pub use crate::completion::{
 // There also snippet completions:
 //
 // .Expressions
-// - `pd` -> `println!("{:?}")`
+// - `pd` -> `eprintln!(" = {:?}", );")`
-// - `ppd` -> `println!("{:#?}")`
+// - `ppd` -> `eprintln!(" = {:#?}", );`
 //
 // .Items
-// - `tfn` -> `#[test] fn f(){}`
+// - `tfn` -> `#[test] fn feature(){}`
 // - `tmod` ->
 // ```rust
 // #[cfg(test)]
@@ -75,7 +75,7 @@ pub use crate::completion::{
 //     use super::*;
 //
 //     #[test]
-//     fn test_fn() {}
+//     fn test_name() {}
 // }
 // ```
@@ -137,8 +137,8 @@ mod tests {
        documentation: &'a str,
    }
-    fn check_detail_and_documentation(fixture: &str, expected: DetailAndDocumentation) {
+    fn check_detail_and_documentation(ra_fixture: &str, expected: DetailAndDocumentation) {
-        let (analysis, position) = analysis_and_position(fixture);
+        let (analysis, position) = analysis_and_position(ra_fixture);
        let config = CompletionConfig::default();
        let completions = analysis.completions(&config, position).unwrap().unwrap();
        for item in completions {
diff --git a/crates/ra_ide/src/completion/complete_keyword.rs b/crates/ra_ide/src/completion/complete_keyword.rs
index 3b174f916..e599cc3d1 100644
--- a/crates/ra_ide/src/completion/complete_keyword.rs
+++ b/crates/ra_ide/src/completion/complete_keyword.rs
@@ -1,6 +1,6 @@
 //! FIXME: write short doc here
-use ra_syntax::ast;
+use ra_syntax::{ast, SyntaxKind};
 use crate::completion::{
    CompletionContext, CompletionItem, CompletionItemKind, CompletionKind, Completions,
@@ -37,6 +37,10 @@ pub(super) fn complete_use_tree_keyword(acc: &mut Completions, ctx: &CompletionC
 }
 pub(super) fn complete_expr_keyword(acc: &mut Completions, ctx: &CompletionContext) {
+    if ctx.token.kind() == SyntaxKind::COMMENT {
+        return;
+    }
    let has_trait_or_impl_parent = ctx.has_impl_parent || ctx.has_trait_parent;
    if ctx.trait_as_prev_sibling || ctx.impl_as_prev_sibling {
        add_keyword(ctx, acc, "where", "where ");
diff --git a/crates/ra_ide/src/completion/presentation.rs b/crates/ra_ide/src/completion/presentation.rs
index 4fdc2f0bb..b18279746 100644
--- a/crates/ra_ide/src/completion/presentation.rs
+++ b/crates/ra_ide/src/completion/presentation.rs
@@ -1516,4 +1516,54 @@ mod tests {
        "###
        );
    }
+    #[test]
+    fn no_keyword_autocompletion_on_line_comments() {
+        assert_debug_snapshot!(
+        do_completion(
+                r"
+                    fn test() {
+                        let x = 2; // A comment<|>
+                    }
+                    ",
+                CompletionKind::Keyword
+        ),
+            @r###"
+            []
+            "###
+        );
+    }
+    #[test]
+    fn no_keyword_autocompletion_on_multi_line_comments() {
+        assert_debug_snapshot!(
+        do_completion(
+                r"
+                    /*
+                    Some multi-line comment<|>
+                    */
+                    ",
+                CompletionKind::Keyword
+        ),
+            @r###"
+            []
+            "###
+        );
+    }
+    #[test]
+    fn no_keyword_autocompletion_on_doc_comments() {
+        assert_debug_snapshot!(
+        do_completion(
+                r"
+                    /// Some doc comment
+                    /// let test<|> = 1
+                    ",
+                CompletionKind::Keyword
+        ),
+            @r###"
+            []
+            "###
+        );
+    }
 }
diff --git a/crates/ra_ide/src/diagnostics.rs b/crates/ra_ide/src/diagnostics.rs
index 05fb799d6..46f8c31c7 100644
--- a/crates/ra_ide/src/diagnostics.rs
+++ b/crates/ra_ide/src/diagnostics.rs
@@ -324,10 +324,10 @@ mod tests {
    ///  * a diagnostic is produced
    ///  * this diagnostic touches the input cursor position
    ///  * that the contents of the file containing the cursor match `after` after the diagnostic fix is applied
-    fn check_apply_diagnostic_fix_from_position(fixture: &str, after: &str) {
+    fn check_apply_diagnostic_fix_from_position(ra_fixture: &str, after: &str) {
        let after = trim_indent(after);
-        let (analysis, file_position) = analysis_and_position(fixture);
+        let (analysis, file_position) = analysis_and_position(ra_fixture);
        let diagnostic = analysis.diagnostics(file_position.file_id).unwrap().pop().unwrap();
        let mut fix = diagnostic.fix.unwrap();
        let edit = fix.source_change.source_file_edits.pop().unwrap().edit;
@@ -365,14 +365,14 @@ mod tests {
    /// Takes a multi-file input fixture with annotated cursor position and checks that no diagnostics
    /// apply to the file containing the cursor.
-    fn check_no_diagnostic_for_target_file(fixture: &str) {
+    fn check_no_diagnostic_for_target_file(ra_fixture: &str) {
-        let (analysis, file_position) = analysis_and_position(fixture);
+        let (analysis, file_position) = analysis_and_position(ra_fixture);
        let diagnostics = analysis.diagnostics(file_position.file_id).unwrap();
        assert_eq!(diagnostics.len(), 0);
    }
-    fn check_no_diagnostic(content: &str) {
+    fn check_no_diagnostic(ra_fixture: &str) {
-        let (analysis, file_id) = single_file(content);
+        let (analysis, file_id) = single_file(ra_fixture);
        let diagnostics = analysis.diagnostics(file_id).unwrap();
        assert_eq!(diagnostics.len(), 0, "expected no diagnostic, found one");
    }
@@ -473,7 +473,8 @@ mod tests {
    #[test]
    fn test_wrap_return_type_not_applicable_when_expr_type_does_not_match_ok_type() {
-        let content = r#"
+        check_no_diagnostic_for_target_file(
+            r"
            //- /main.rs
            use core::result::Result::{self, Ok, Err};
@@ -485,13 +486,14 @@ mod tests {
            pub mod result {
                pub enum Result<T, E> { Ok(T), Err(E) }
            }
-        "#;
+        ",
-        check_no_diagnostic_for_target_file(content);
+        );
    }
    #[test]
    fn test_wrap_return_type_not_applicable_when_return_type_is_not_result() {
-        let content = r#"
+        check_no_diagnostic_for_target_file(
+            r"
            //- /main.rs
            use core::result::Result::{self, Ok, Err};
@@ -508,8 +510,8 @@ mod tests {
            pub mod result {
                pub enum Result<T, E> { Ok(T), Err(E) }
            }
-        "#;
+        ",
-        check_no_diagnostic_for_target_file(content);
+        );
    }
    #[test]
@@ -618,7 +620,8 @@ mod tests {
    #[test]
    fn test_fill_struct_fields_no_diagnostic() {
-        let content = r"
+        check_no_diagnostic(
+            r"
            struct TestStruct {
                one: i32,
                two: i64,
@@ -628,14 +631,14 @@ mod tests {
                let one = 1;
                let s = TestStruct{ one, two: 2 };
            }
-        ";
+        ",
+        );
-        check_no_diagnostic(content);
    }
    #[test]
    fn test_fill_struct_fields_no_diagnostic_on_spread() {
-        let content = r"
+        check_no_diagnostic(
+            r"
            struct TestStruct {
                one: i32,
                two: i64,
@@ -645,9 +648,8 @@ mod tests {
                let one = 1;
                let s = TestStruct{ ..a };
            }
-        ";
+        ",
+        );
-        check_no_diagnostic(content);
    }
    #[test]
diff --git a/crates/ra_ide/src/display/structure.rs b/crates/ra_ide/src/display/structure.rs
index aad5a8e4d..c22a5d17b 100644
--- a/crates/ra_ide/src/display/structure.rs
+++ b/crates/ra_ide/src/display/structure.rs
@@ -173,12 +173,19 @@ fn structure_node(node: &SyntaxNode) -> Option<StructureNode> {
 #[cfg(test)]
 mod tests {
+    use expect::{expect, Expect};
    use super::*;
-    use insta::assert_debug_snapshot;
+    fn check(ra_fixture: &str, expect: Expect) {
+        let file = SourceFile::parse(ra_fixture).ok().unwrap();
+        let structure = file_structure(&file);
+        expect.assert_debug_eq(&structure)
+    }
    #[test]
    fn test_file_structure() {
-        let file = SourceFile::parse(
+        check(
            r#"
 struct Foo {
    x: i32
@@ -223,216 +230,211 @@ fn obsolete() {}
 #[deprecated(note = "for awhile")]
 fn very_obsolete() {}
 "#,
-        )
+            expect![[r#"
-        .ok()
+                [
-        .unwrap();
+                    StructureNode {
-        let structure = file_structure(&file);
+                        parent: None,
-        assert_debug_snapshot!(structure,
+                        label: "Foo",
-        @r###"
+                        navigation_range: 8..11,
-        [
+                        node_range: 1..26,
-            StructureNode {
+                        kind: STRUCT_DEF,
-                parent: None,
+                        detail: None,
-                label: "Foo",
+                        deprecated: false,
-                navigation_range: 8..11,
+                    },
-                node_range: 1..26,
+                    StructureNode {
-                kind: STRUCT_DEF,
+                        parent: Some(
-                detail: None,
+                            0,
-                deprecated: false,
+                        ),
-            },
+                        label: "x",
-            StructureNode {
+                        navigation_range: 18..19,
-                parent: Some(
+                        node_range: 18..24,
-                    0,
+                        kind: RECORD_FIELD_DEF,
-                ),
+                        detail: Some(
-                label: "x",
+                            "i32",
-                navigation_range: 18..19,
+                        ),
-                node_range: 18..24,
+                        deprecated: false,
-                kind: RECORD_FIELD_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "i32",
+                        parent: None,
-                ),
+                        label: "m",
-                deprecated: false,
+                        navigation_range: 32..33,
-            },
+                        node_range: 28..158,
-            StructureNode {
+                        kind: MODULE,
-                parent: None,
+                        detail: None,
-                label: "m",
+                        deprecated: false,
-                navigation_range: 32..33,
+                    },
-                node_range: 28..158,
+                    StructureNode {
-                kind: MODULE,
+                        parent: Some(
-                detail: None,
+                            2,
-                deprecated: false,
+                        ),
-            },
+                        label: "bar1",
-            StructureNode {
+                        navigation_range: 43..47,
-                parent: Some(
+                        node_range: 40..52,
-                    2,
+                        kind: FN_DEF,
-                ),
+                        detail: Some(
-                label: "bar1",
+                            "fn()",
-                navigation_range: 43..47,
+                        ),
-                node_range: 40..52,
+                        deprecated: false,
-                kind: FN_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "fn()",
+                        parent: Some(
-                ),
+                            2,
-                deprecated: false,
+                        ),
-            },
+                        label: "bar2",
-            StructureNode {
+                        navigation_range: 60..64,
-                parent: Some(
+                        node_range: 57..81,
-                    2,
+                        kind: FN_DEF,
-                ),
+                        detail: Some(
-                label: "bar2",
+                            "fn<T>(t: T) -> T",
-                navigation_range: 60..64,
+                        ),
-                node_range: 57..81,
+                        deprecated: false,
-                kind: FN_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "fn<T>(t: T) -> T",
+                        parent: Some(
-                ),
+                            2,
-                deprecated: false,
+                        ),
-            },
+                        label: "bar3",
-            StructureNode {
+                        navigation_range: 89..93,
-                parent: Some(
+                        node_range: 86..156,
-                    2,
+                        kind: FN_DEF,
-                ),
+                        detail: Some(
-                label: "bar3",
+                            "fn<A, B>(a: A, b: B) -> Vec< u32 >",
-                navigation_range: 89..93,
+                        ),
-                node_range: 86..156,
+                        deprecated: false,
-                kind: FN_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "fn<A, B>(a: A, b: B) -> Vec< u32 >",
+                        parent: None,
-                ),
+                        label: "E",
-                deprecated: false,
+                        navigation_range: 165..166,
-            },
+                        node_range: 160..180,
-            StructureNode {
+                        kind: ENUM_DEF,
-                parent: None,
+                        detail: None,
-                label: "E",
+                        deprecated: false,
-                navigation_range: 165..166,
+                    },
-                node_range: 160..180,
+                    StructureNode {
-                kind: ENUM_DEF,
+                        parent: Some(
-                detail: None,
+                            6,
-                deprecated: false,
+                        ),
-            },
+                        label: "X",
-            StructureNode {
+                        navigation_range: 169..170,
-                parent: Some(
+                        node_range: 169..170,
-                    6,
+                        kind: ENUM_VARIANT,
-                ),
+                        detail: None,
-                label: "X",
+                        deprecated: false,
-                navigation_range: 169..170,
+                    },
-                node_range: 169..170,
+                    StructureNode {
-                kind: ENUM_VARIANT,
+                        parent: Some(
-                detail: None,
+                            6,
-                deprecated: false,
+                        ),
-            },
+                        label: "Y",
-            StructureNode {
+                        navigation_range: 172..173,
-                parent: Some(
+                        node_range: 172..178,
-                    6,
+                        kind: ENUM_VARIANT,
-                ),
+                        detail: None,
-                label: "Y",
+                        deprecated: false,
-                navigation_range: 172..173,
+                    },
-                node_range: 172..178,
+                    StructureNode {
-                kind: ENUM_VARIANT,
+                        parent: None,
-                detail: None,
+                        label: "T",
-                deprecated: false,
+                        navigation_range: 186..187,
-            },
+                        node_range: 181..193,
-            StructureNode {
+                        kind: TYPE_ALIAS_DEF,
-                parent: None,
+                        detail: Some(
-                label: "T",
+                            "()",
-                navigation_range: 186..187,
+                        ),
-                node_range: 181..193,
+                        deprecated: false,
-                kind: TYPE_ALIAS_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "()",
+                        parent: None,
-                ),
+                        label: "S",
-                deprecated: false,
+                        navigation_range: 201..202,
-            },
+                        node_range: 194..213,
-            StructureNode {
+                        kind: STATIC_DEF,
-                parent: None,
+                        detail: Some(
-                label: "S",
+                            "i32",
-                navigation_range: 201..202,
+                        ),
-                node_range: 194..213,
+                        deprecated: false,
-                kind: STATIC_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "i32",
+                        parent: None,
-                ),
+                        label: "C",
-                deprecated: false,
+                        navigation_range: 220..221,
-            },
+                        node_range: 214..232,
-            StructureNode {
+                        kind: CONST_DEF,
-                parent: None,
+                        detail: Some(
-                label: "C",
+                            "i32",
-                navigation_range: 220..221,
+                        ),
-                node_range: 214..232,
+                        deprecated: false,
-                kind: CONST_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "i32",
+                        parent: None,
-                ),
+                        label: "impl E",
-                deprecated: false,
+                        navigation_range: 239..240,
-            },
+                        node_range: 234..243,
-            StructureNode {
+                        kind: IMPL_DEF,
-                parent: None,
+                        detail: None,
-                label: "impl E",
+                        deprecated: false,
-                navigation_range: 239..240,
+                    },
-                node_range: 234..243,
+                    StructureNode {
-                kind: IMPL_DEF,
+                        parent: None,
-                detail: None,
+                        label: "impl fmt::Debug for E",
-                deprecated: false,
+                        navigation_range: 265..266,
-            },
+                        node_range: 245..269,
-            StructureNode {
+                        kind: IMPL_DEF,
-                parent: None,
+                        detail: None,
-                label: "impl fmt::Debug for E",
+                        deprecated: false,
-                navigation_range: 265..266,
+                    },
-                node_range: 245..269,
+                    StructureNode {
-                kind: IMPL_DEF,
+                        parent: None,
-                detail: None,
+                        label: "mc",
-                deprecated: false,
+                        navigation_range: 284..286,
-            },
+                        node_range: 271..303,
-            StructureNode {
+                        kind: MACRO_CALL,
-                parent: None,
+                        detail: None,
-                label: "mc",
+                        deprecated: false,
-                navigation_range: 284..286,
+                    },
-                node_range: 271..303,
+                    StructureNode {
-                kind: MACRO_CALL,
+                        parent: None,
-                detail: None,
+                        label: "mcexp",
-                deprecated: false,
+                        navigation_range: 334..339,
-            },
+                        node_range: 305..356,
-            StructureNode {
+                        kind: MACRO_CALL,
-                parent: None,
+                        detail: None,
-                label: "mcexp",
+                        deprecated: false,
-                navigation_range: 334..339,
+                    },
-                node_range: 305..356,
+                    StructureNode {
-                kind: MACRO_CALL,
+                        parent: None,
-                detail: None,
+                        label: "mcexp",
-                deprecated: false,
+                        navigation_range: 387..392,
-            },
+                        node_range: 358..409,
-            StructureNode {
+                        kind: MACRO_CALL,
-                parent: None,
+                        detail: None,
-                label: "mcexp",
+                        deprecated: false,
-                navigation_range: 387..392,
+                    },
-                node_range: 358..409,
+                    StructureNode {
-                kind: MACRO_CALL,
+                        parent: None,
-                detail: None,
+                        label: "obsolete",
-                deprecated: false,
+                        navigation_range: 428..436,
-            },
+                        node_range: 411..441,
-            StructureNode {
+                        kind: FN_DEF,
-                parent: None,
+                        detail: Some(
-                label: "obsolete",
+                            "fn()",
-                navigation_range: 428..436,
+                        ),
-                node_range: 411..441,
+                        deprecated: true,
-                kind: FN_DEF,
+                    },
-                detail: Some(
+                    StructureNode {
-                    "fn()",
+                        parent: None,
-                ),
+                        label: "very_obsolete",
-                deprecated: true,
+                        navigation_range: 481..494,
-            },
+                        node_range: 443..499,
-            StructureNode {
+                        kind: FN_DEF,
-                parent: None,
+                        detail: Some(
-                label: "very_obsolete",
+                            "fn()",
-                navigation_range: 481..494,
+                        ),
-                node_range: 443..499,
+                        deprecated: true,
-                kind: FN_DEF,
+                    },
-                detail: Some(
+                ]
-                    "fn()",
+            "#]],
-                ),
+        );
-                deprecated: true,
-            },
-        ]
-        "###
-                );
    }
 }
diff --git a/crates/ra_ide/src/expand_macro.rs b/crates/ra_ide/src/expand_macro.rs
index 54a47aac0..043515f54 100644
--- a/crates/ra_ide/src/expand_macro.rs
+++ b/crates/ra_ide/src/expand_macro.rs
@@ -2,7 +2,9 @@ use hir::Semantics;
 use ra_ide_db::RootDatabase;
 use ra_syntax::{
    algo::{find_node_at_offset, SyntaxRewriter},
-    ast, AstNode, NodeOrToken, SyntaxKind, SyntaxNode, WalkEvent, T,
+    ast, AstNode, NodeOrToken, SyntaxKind,
+    SyntaxKind::*,
+    SyntaxNode, WalkEvent, T,
 };
 use crate::FilePosition;
@@ -65,8 +67,6 @@ fn expand_macro_recur(
 // FIXME: It would also be cool to share logic here and in the mbe tests,
 // which are pretty unreadable at the moment.
 fn insert_whitespaces(syn: SyntaxNode) -> String {
-    use SyntaxKind::*;
    let mut res = String::new();
    let mut token_iter = syn
        .preorder_with_tokens()
@@ -120,175 +120,164 @@ fn insert_whitespaces(syn: SyntaxNode) -> String {
 #[cfg(test)]
 mod tests {
-    use insta::assert_snapshot;
+    use expect::{expect, Expect};
    use crate::mock_analysis::analysis_and_position;
-    use super::*;
+    fn check(ra_fixture: &str, expect: Expect) {
+        let (analysis, pos) = analysis_and_position(ra_fixture);
-    fn check_expand_macro(fixture: &str) -> ExpandedMacro {
+        let expansion = analysis.expand_macro(pos).unwrap().unwrap();
-        let (analysis, pos) = analysis_and_position(fixture);
+        let actual = format!("{}\n{}", expansion.name, expansion.expansion);
-        analysis.expand_macro(pos).unwrap().unwrap()
+        expect.assert_eq(&actual);
    }
    #[test]
    fn macro_expand_recursive_expansion() {
-        let res = check_expand_macro(
+        check(
            r#"
-        //- /lib.rs
+macro_rules! bar {
-        macro_rules! bar {
+    () => { fn  b() {} }
-            () => { fn  b() {} }
+}
-        }
+macro_rules! foo {
-        macro_rules! foo {
+    () => { bar!(); }
-            () => { bar!(); }
+}
-        }
+macro_rules! baz {
-        macro_rules! baz {
+    () => { foo!(); }
-            () => { foo!(); }
+}
-        }
+f<|>oo!();
-        f<|>oo!();
+"#,
-        "#,
+            expect![[r#"
+                foo
+                fn b(){}
+            "#]],
        );
-        assert_eq!(res.name, "foo");
-        assert_snapshot!(res.expansion, @r###"
-fn b(){}
-"###);
    }
    #[test]
    fn macro_expand_multiple_lines() {
-        let res = check_expand_macro(
+        check(
            r#"
-        //- /lib.rs
+macro_rules! foo {
-        macro_rules! foo {
+    () => {
-            () => {
+        fn some_thing() -> u32 {
-                fn some_thing() -> u32 {
+            let a = 0;
-                    let a = 0;
+            a + 10
-                    a + 10
-                }
-            }
        }
-        f<|>oo!();
+    }
+}
+f<|>oo!();
        "#,
+            expect![[r#"
+            foo
+            fn some_thing() -> u32 {
+              let a = 0;
+              a+10
+            }"#]],
        );
-        assert_eq!(res.name, "foo");
-        assert_snapshot!(res.expansion, @r###"
-fn some_thing() -> u32 {
-  let a = 0;
-  a+10
-}
-"###);
    }
    #[test]
    fn macro_expand_match_ast() {
-        let res = check_expand_macro(
+        check(
            r#"
-        //- /lib.rs
+macro_rules! match_ast {
-        macro_rules! match_ast {
+    (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
-            (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
+    (match ($node:expr) {
+        $( ast::$ast:ident($it:ident) => $res:block, )*
+        _ => $catch_all:expr $(,)?
+    }) => {{
+        $( if let Some($it) = ast::$ast::cast($node.clone()) $res else )*
+        { $catch_all }
+    }};
+}
-            (match ($node:expr) {
+fn main() {
-                $( ast::$ast:ident($it:ident) => $res:block, )*
+    mat<|>ch_ast! {
-                _ => $catch_all:expr $(,)?
+        match container {
-            }) => {{
+            ast::TraitDef(it) => {},
-                $( if let Some($it) = ast::$ast::cast($node.clone()) $res else )*
+            ast::ImplDef(it) => {},
-                { $catch_all }
+            _ => { continue },
-            }};
        }
-        fn main() {
-            mat<|>ch_ast! {
-                match container {
-                    ast::TraitDef(it) => {},
-                    ast::ImplDef(it) => {},
-                    _ => { continue },
-                }
-            }
-        }
-        "#,
-        );
-        assert_eq!(res.name, "match_ast");
-        assert_snapshot!(res.expansion, @r###"
-{
-  if let Some(it) = ast::TraitDef::cast(container.clone()){}
-  else if let Some(it) = ast::ImplDef::cast(container.clone()){}
-  else {
-    {
-      continue
    }
-  }
 }
-"###);
+"#,
+            expect![[r#"
+       match_ast
+       {
+         if let Some(it) = ast::TraitDef::cast(container.clone()){}
+         else if let Some(it) = ast::ImplDef::cast(container.clone()){}
+         else {
+           {
+             continue
+           }
+         }
+       }"#]],
+        );
    }
    #[test]
    fn macro_expand_match_ast_inside_let_statement() {
-        let res = check_expand_macro(
+        check(
            r#"
-        //- /lib.rs
+macro_rules! match_ast {
-        macro_rules! match_ast {
+    (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
-            (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
+    (match ($node:expr) {}) => {{}};
-            (match ($node:expr) {}) => {{}};
+}
-        }
-        fn main() {
+fn main() {
-            let p = f(|it| {
+    let p = f(|it| {
-                let res = mat<|>ch_ast! { match c {}};
+        let res = mat<|>ch_ast! { match c {}};
-                Some(res)
+        Some(res)
-            })?;
+    })?;
-        }
+}
-        "#,
+"#,
+            expect![[r#"
+                match_ast
+                {}
+            "#]],
        );
-        assert_eq!(res.name, "match_ast");
-        assert_snapshot!(res.expansion, @r###"{}"###);
    }
    #[test]
    fn macro_expand_inner_macro_fail_to_expand() {
-        let res = check_expand_macro(
+        check(
            r#"
-        //- /lib.rs
+macro_rules! bar {
-        macro_rules! bar {
+    (BAD) => {};
-            (BAD) => {};
+}
-        }
+macro_rules! foo {
-        macro_rules! foo {
+    () => {bar!()};
-            () => {bar!()};
+}
-        }
-        fn main() {
+fn main() {
-            let res = fo<|>o!();
+    let res = fo<|>o!();
-        }
+}
-        "#,
+"#,
+            expect![[r#"
+                foo
+            "#]],
        );
-        assert_eq!(res.name, "foo");
-        assert_snapshot!(res.expansion, @r###""###);
    }
    #[test]
    fn macro_expand_with_dollar_crate() {
-        let res = check_expand_macro(
+        check(
            r#"
-        //- /lib.rs
+#[macro_export]
-        #[macro_export]
+macro_rules! bar {
-        macro_rules! bar {
+    () => {0};
-            () => {0};
+}
-        }
+macro_rules! foo {
-        macro_rules! foo {
+    () => {$crate::bar!()};
-            () => {$crate::bar!()};
+}
-        }
-        fn main() {
+fn main() {
-            let res = fo<|>o!();
+    let res = fo<|>o!();
-        }
+}
-        "#,
+"#,
+            expect![[r#"
+                foo
+                0 "#]],
        );
-        assert_eq!(res.name, "foo");
-        assert_snapshot!(res.expansion, @r###"0"###);
    }
 }
diff --git a/crates/ra_ide/src/folding_ranges.rs b/crates/ra_ide/src/folding_ranges.rs
index 8657377de..5cec689f8 100644
--- a/crates/ra_ide/src/folding_ranges.rs
+++ b/crates/ra_ide/src/folding_ranges.rs
@@ -15,6 +15,7 @@ pub enum FoldKind {
    Imports,
    Mods,
    Block,
+    ArgList,
 }
 #[derive(Debug)]
@@ -83,6 +84,7 @@ fn fold_kind(kind: SyntaxKind) -> Option<FoldKind> {
    match kind {
        COMMENT => Some(FoldKind::Comment),
        USE_ITEM => Some(FoldKind::Imports),
+        ARG_LIST => Some(FoldKind::ArgList),
        RECORD_FIELD_DEF_LIST
        | RECORD_FIELD_PAT_LIST
        | ITEM_LIST
@@ -196,89 +198,85 @@ fn contiguous_range_for_comment(
 #[cfg(test)]
 mod tests {
+    use test_utils::extract_tags;
    use super::*;
-    use test_utils::extract_ranges;
-    fn do_check(text: &str, fold_kinds: &[FoldKind]) {
+    fn check(ra_fixture: &str) {
-        let (ranges, text) = extract_ranges(text, "fold");
+        let (ranges, text) = extract_tags(ra_fixture, "fold");
        let parse = SourceFile::parse(&text);
        let folds = folding_ranges(&parse.tree());
        assert_eq!(
            folds.len(),
            ranges.len(),
            "The amount of folds is different than the expected amount"
        );
-        assert_eq!(
-            folds.len(),
+        for (fold, (range, attr)) in folds.iter().zip(ranges.into_iter()) {
-            fold_kinds.len(),
-            "The amount of fold kinds is different than the expected amount"
-        );
-        for ((fold, range), fold_kind) in
-            folds.iter().zip(ranges.into_iter()).zip(fold_kinds.iter())
-        {
            assert_eq!(fold.range.start(), range.start());
            assert_eq!(fold.range.end(), range.end());
-            assert_eq!(&fold.kind, fold_kind);
+            let kind = match fold.kind {
+                FoldKind::Comment => "comment",
+                FoldKind::Imports => "imports",
+                FoldKind::Mods => "mods",
+                FoldKind::Block => "block",
+                FoldKind::ArgList => "arglist",
+            };
+            assert_eq!(kind, &attr.unwrap());
        }
    }
    #[test]
    fn test_fold_comments() {
-        let text = r#"
+        check(
-<fold>// Hello
+            r#"
+<fold comment>// Hello
 // this is a multiline
 // comment
 //</fold>
 // But this is not
-fn main() <fold>{
+fn main() <fold block>{
-    <fold>// We should
+    <fold comment>// We should
    // also
    // fold
    // this one.</fold>
-    <fold>//! But this one is different
+    <fold comment>//! But this one is different
    //! because it has another flavor</fold>
-    <fold>/* As does this
+    <fold comment>/* As does this
    multiline comment */</fold>
-}</fold>"#;
+}</fold>"#,
+        );
-        let fold_kinds = &[
-            FoldKind::Comment,
-            FoldKind::Block,
-            FoldKind::Comment,
-            FoldKind::Comment,
-            FoldKind::Comment,
-        ];
-        do_check(text, fold_kinds);
    }
    #[test]
    fn test_fold_imports() {
-        let text = r#"
+        check(
-<fold>use std::<fold>{
+            r#"
+<fold imports>use std::<fold block>{
    str,
    vec,
    io as iop
 }</fold>;</fold>
-fn main() <fold>{
+fn main() <fold block>{
-}</fold>"#;
+}</fold>"#,
+        );
-        let folds = &[FoldKind::Imports, FoldKind::Block, FoldKind::Block];
-        do_check(text, folds);
    }
    #[test]
    fn test_fold_mods() {
-        let text = r#"
+        check(
+            r#"
 pub mod foo;
-<fold>mod after_pub;
+<fold mods>mod after_pub;
 mod after_pub_next;</fold>
-<fold>mod before_pub;
+<fold mods>mod before_pub;
 mod before_pub_next;</fold>
 pub mod bar;
@@ -286,90 +284,93 @@ mod not_folding_single;
 pub mod foobar;
 pub not_folding_single_next;
-<fold>#[cfg(test)]
+<fold mods>#[cfg(test)]
 mod with_attribute;
 mod with_attribute_next;</fold>
-fn main() <fold>{
+fn main() <fold block>{
-}</fold>"#;
+}</fold>"#,
+        );
-        let folds = &[FoldKind::Mods, FoldKind::Mods, FoldKind::Mods, FoldKind::Block];
-        do_check(text, folds);
    }
    #[test]
    fn test_fold_import_groups() {
-        let text = r#"
+        check(
-<fold>use std::str;
+            r#"
+<fold imports>use std::str;
 use std::vec;
 use std::io as iop;</fold>
-<fold>use std::mem;
+<fold imports>use std::mem;
 use std::f64;</fold>
 use std::collections::HashMap;
 // Some random comment
 use std::collections::VecDeque;
-fn main() <fold>{
+fn main() <fold block>{
-}</fold>"#;
+}</fold>"#,
+        );
-        let folds = &[FoldKind::Imports, FoldKind::Imports, FoldKind::Block];
-        do_check(text, folds);
    }
    #[test]
    fn test_fold_import_and_groups() {
-        let text = r#"
+        check(
-<fold>use std::str;
+            r#"
+<fold imports>use std::str;
 use std::vec;
 use std::io as iop;</fold>
-<fold>use std::mem;
+<fold imports>use std::mem;
 use std::f64;</fold>
-<fold>use std::collections::<fold>{
+<fold imports>use std::collections::<fold block>{
    HashMap,
    VecDeque,
 }</fold>;</fold>
 // Some random comment
-fn main() <fold>{
+fn main() <fold block>{
-}</fold>"#;
+}</fold>"#,
+        );
-        let folds = &[
-            FoldKind::Imports,
-            FoldKind::Imports,
-            FoldKind::Imports,
-            FoldKind::Block,
-            FoldKind::Block,
-        ];
-        do_check(text, folds);
    }
    #[test]
    fn test_folds_macros() {
-        let text = r#"
+        check(
-macro_rules! foo <fold>{
+            r#"
+macro_rules! foo <fold block>{
    ($($tt:tt)*) => { $($tt)* }
 }</fold>
-"#;
+"#,
+        );
-        let folds = &[FoldKind::Block];
-        do_check(text, folds);
    }
    #[test]
    fn test_fold_match_arms() {
-        let text = r#"
+        check(
-fn main() <fold>{
+            r#"
-    match 0 <fold>{
+fn main() <fold block>{
+    match 0 <fold block>{
        0 => 0,
        _ => 1,
    }</fold>
-}</fold>"#;
+}</fold>"#,
+        );
+    }
-        let folds = &[FoldKind::Block, FoldKind::Block];
+    #[test]
-        do_check(text, folds);
+    fn fold_big_calls() {
+        check(
+            r#"
+fn main() <fold block>{
+    frobnicate<fold arglist>(
+        1,
+        2,
+        3,
+    )</fold>
+}</fold>
+        "#,
+        )
    }
 }
diff --git a/crates/ra_ide/src/goto_implementation.rs b/crates/ra_ide/src/goto_implementation.rs
index 99a7022a4..9acc960fc 100644
--- a/crates/ra_ide/src/goto_implementation.rs
+++ b/crates/ra_ide/src/goto_implementation.rs
@@ -219,6 +219,10 @@ impl T for &Foo {}
  #[derive(Copy)]
 //^^^^^^^^^^^^^^^
 struct Foo<|>;
+mod marker {
+    trait Copy {}
+}
 "#,
        );
    }
diff --git a/crates/ra_ide/src/goto_type_definition.rs b/crates/ra_ide/src/goto_type_definition.rs
index 91a3097fb..7eb40d637 100644
--- a/crates/ra_ide/src/goto_type_definition.rs
+++ b/crates/ra_ide/src/goto_type_definition.rs
@@ -55,8 +55,8 @@ fn pick_best(tokens: TokenAtOffset<SyntaxToken>) -> Option<SyntaxToken> {
 mod tests {
    use crate::mock_analysis::analysis_and_position;
-    fn check_goto(fixture: &str, expected: &str) {
+    fn check_goto(ra_fixture: &str, expected: &str) {
-        let (analysis, pos) = analysis_and_position(fixture);
+        let (analysis, pos) = analysis_and_position(ra_fixture);
        let mut navs = analysis.goto_type_definition(pos).unwrap().unwrap().info;
        assert_eq!(navs.len(), 1);
@@ -67,7 +67,7 @@ mod tests {
    #[test]
    fn goto_type_definition_works_simple() {
        check_goto(
-            "
+            r"
            //- /lib.rs
            struct Foo;
            fn foo() {
@@ -82,7 +82,7 @@ mod tests {
    #[test]
    fn goto_type_definition_works_simple_ref() {
        check_goto(
-            "
+            r"
            //- /lib.rs
            struct Foo;
            fn foo() {
@@ -97,7 +97,7 @@ mod tests {
    #[test]
    fn goto_type_definition_works_through_macro() {
        check_goto(
-            "
+            r"
            //- /lib.rs
            macro_rules! id {
                ($($tt:tt)*) => { $($tt)* }
@@ -116,7 +116,7 @@ mod tests {
    #[test]
    fn goto_type_definition_for_param() {
        check_goto(
-            "
+            r"
            //- /lib.rs
            struct Foo;
            fn foo(<|>f: Foo) {}
@@ -128,7 +128,7 @@ mod tests {
    #[test]
    fn goto_type_definition_for_tuple_field() {
        check_goto(
-            "
+            r"
            //- /lib.rs
            struct Foo;
            struct Bar(Foo);
diff --git a/crates/ra_ide/src/hover.rs b/crates/ra_ide/src/hover.rs
index c3e36a387..eaba2b61e 100644
--- a/crates/ra_ide/src/hover.rs
+++ b/crates/ra_ide/src/hover.rs
@@ -417,8 +417,8 @@ mod tests {
        assert_eq!(offset, position.into());
    }
-    fn check_hover_result(fixture: &str, expected: &[&str]) -> (String, Vec<HoverAction>) {
+    fn check_hover_result(ra_fixture: &str, expected: &[&str]) -> (String, Vec<HoverAction>) {
-        let (analysis, position) = analysis_and_position(fixture);
+        let (analysis, position) = analysis_and_position(ra_fixture);
        let hover = analysis.hover(position).unwrap().unwrap();
        let mut results = Vec::from(hover.info.results());
        results.sort();
@@ -435,8 +435,8 @@ mod tests {
        (content[hover.range].to_string(), hover.info.actions().to_vec())
    }
-    fn check_hover_no_result(fixture: &str) {
+    fn check_hover_no_result(ra_fixture: &str) {
-        let (analysis, position) = analysis_and_position(fixture);
+        let (analysis, position) = analysis_and_position(ra_fixture);
        assert!(analysis.hover(position).unwrap().is_none());
    }
@@ -923,7 +923,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_through_macro() {
        let (hover_on, _) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            macro_rules! id {
                ($($tt:tt)*) => { $($tt)* }
@@ -944,7 +944,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_through_expr_in_macro() {
        let (hover_on, _) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            macro_rules! id {
                ($($tt:tt)*) => { $($tt)* }
@@ -962,7 +962,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_through_expr_in_macro_recursive() {
        let (hover_on, _) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            macro_rules! id_deep {
                ($($tt:tt)*) => { $($tt)* }
@@ -983,7 +983,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_through_func_in_macro_recursive() {
        let (hover_on, _) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            macro_rules! id_deep {
                ($($tt:tt)*) => { $($tt)* }
@@ -1026,7 +1026,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_through_assert_macro() {
        let (hover_on, _) = check_hover_result(
-            r#"
+            r"
            //- /lib.rs
            #[rustc_builtin_macro]
            macro_rules! assert {}
@@ -1035,7 +1035,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
            fn foo() {
                assert!(ba<|>r());
            }
-            "#,
+            ",
            &["fn bar() -> bool"],
        );
@@ -1077,14 +1077,14 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_function_show_qualifiers() {
        check_hover_result(
-            "
+            r"
            //- /lib.rs
            async fn foo<|>() {}
            ",
            &["async fn foo()"],
        );
        check_hover_result(
-            "
+            r"
            //- /lib.rs
            pub const unsafe fn foo<|>() {}
            ",
@@ -1102,7 +1102,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_trait_show_qualifiers() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            unsafe trait foo<|>() {}
            ",
@@ -1114,7 +1114,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_mod_with_same_name_as_function() {
        check_hover_result(
-            "
+            r"
            //- /lib.rs
            use self::m<|>y::Bar;
@@ -1237,7 +1237,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_trait_has_impl_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait foo<|>() {}
            ",
@@ -1249,7 +1249,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_struct_has_impl_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            struct foo<|>() {}
            ",
@@ -1261,7 +1261,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_union_has_impl_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            union foo<|>() {}
            ",
@@ -1273,7 +1273,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_enum_has_impl_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            enum foo<|>() {
                A,
@@ -1288,7 +1288,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_test_has_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            #[test]
            fn foo_<|>test() {}
@@ -1332,7 +1332,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_test_mod_has_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            mod tests<|> {
                #[test]
@@ -1373,7 +1373,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_struct_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            struct S{ f1: u32 }
@@ -1416,7 +1416,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_generic_struct_has_goto_type_actions() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            struct Arg(u32);
            struct S<T>{ f1: T }
@@ -1479,7 +1479,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_generic_struct_has_flattened_goto_type_actions() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            struct Arg(u32);
            struct S<T>{ f1: T }
@@ -1542,7 +1542,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_tuple_has_goto_type_actions() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            struct A(u32);
            struct B(u32);
@@ -1627,7 +1627,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_return_impl_trait_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            trait Foo {}
@@ -1672,7 +1672,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_generic_return_impl_trait_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            trait Foo<T> {}
            struct S;
@@ -1737,7 +1737,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_return_impl_traits_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            trait Foo {}
            trait Bar {}
@@ -1802,7 +1802,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_generic_return_impl_traits_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            trait Foo<T> {}
            trait Bar<T> {}
@@ -1907,7 +1907,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_arg_impl_trait_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait Foo {}
            fn foo(ar<|>g: &impl Foo) {}
@@ -1947,7 +1947,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_arg_impl_traits_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait Foo {}
            trait Bar<T> {}
@@ -2028,7 +2028,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_arg_generic_impl_trait_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait Foo<T> {}
            struct S {}
@@ -2088,7 +2088,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_dyn_return_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            trait Foo {}
            struct S;
@@ -2156,7 +2156,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_dyn_arg_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait Foo {}
            fn foo(ar<|>g: &dyn Foo) {}
@@ -2196,7 +2196,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_generic_dyn_arg_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait Foo<T> {}
            struct S {}
@@ -2256,7 +2256,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_goto_type_action_links_order() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /lib.rs
            trait ImplTrait<T> {}
            trait DynTrait<T> {}
@@ -2357,7 +2357,7 @@ fn func(foo: i32) { if true { <|>foo; }; }
    #[test]
    fn test_hover_associated_type_has_goto_type_action() {
        let (_, actions) = check_hover_result(
-            "
+            r"
            //- /main.rs
            trait Foo {
                type Item;
diff --git a/crates/ra_ide/src/lib.rs b/crates/ra_ide/src/lib.rs
index ecac5134e..8660278f1 100644
--- a/crates/ra_ide/src/lib.rs
+++ b/crates/ra_ide/src/lib.rs
@@ -75,7 +75,7 @@ pub use crate::{
    },
 };
-pub use hir::Documentation;
+pub use hir::{Documentation, Semantics};
 pub use ra_assists::{Assist, AssistConfig, AssistId, ResolvedAssist};
 pub use ra_db::{
    Canceled, CrateGraph, CrateId, Edition, FileId, FilePosition, FileRange, SourceRoot,
@@ -385,7 +385,9 @@ impl Analysis {
        position: FilePosition,
        search_scope: Option<SearchScope>,
    ) -> Cancelable<Option<ReferenceSearchResult>> {
-        self.with_db(|db| references::find_all_refs(db, position, search_scope).map(|it| it.info))
+        self.with_db(|db| {
+            references::find_all_refs(&Semantics::new(db), position, search_scope).map(|it| it.info)
+        })
    }
    /// Returns a short text describing element at position.
diff --git a/crates/ra_ide/src/references.rs b/crates/ra_ide/src/references.rs
index 3433fdae3..c2b0d5efe 100644
--- a/crates/ra_ide/src/references.rs
+++ b/crates/ra_ide/src/references.rs
@@ -86,12 +86,11 @@ impl IntoIterator for ReferenceSearchResult {
 }
 pub(crate) fn find_all_refs(
-    db: &RootDatabase,
+    sema: &Semantics<RootDatabase>,
    position: FilePosition,
    search_scope: Option<SearchScope>,
 ) -> Option<RangeInfo<ReferenceSearchResult>> {
    let _p = profile("find_all_refs");
-    let sema = Semantics::new(db);
    let syntax = sema.parse(position.file_id).syntax().clone();
    let (opt_name, search_kind) = if let Some(name) =
@@ -108,15 +107,15 @@ pub(crate) fn find_all_refs(
    let RangeInfo { range, info: def } = find_name(&sema, &syntax, position, opt_name)?;
    let references = def
-        .find_usages(db, search_scope)
+        .find_usages(sema, search_scope)
        .into_iter()
        .filter(|r| search_kind == ReferenceKind::Other || search_kind == r.kind)
        .collect();
-    let decl_range = def.try_to_nav(db)?.range();
+    let decl_range = def.try_to_nav(sema.db)?.range();
    let declaration = Declaration {
-        nav: def.try_to_nav(db)?,
+        nav: def.try_to_nav(sema.db)?,
        kind: ReferenceKind::Other,
        access: decl_access(&def, &syntax, decl_range),
    };
diff --git a/crates/ra_ide/src/references/rename.rs b/crates/ra_ide/src/references/rename.rs
index 7ebc0adcf..b6a2266b4 100644
--- a/crates/ra_ide/src/references/rename.rs
+++ b/crates/ra_ide/src/references/rename.rs
@@ -24,23 +24,24 @@ pub(crate) fn rename(
    position: FilePosition,
    new_name: &str,
 ) -> Option<RangeInfo<SourceChange>> {
+    let sema = Semantics::new(db);
    match lex_single_valid_syntax_kind(new_name)? {
        SyntaxKind::IDENT | SyntaxKind::UNDERSCORE => (),
-        SyntaxKind::SELF_KW => return rename_to_self(db, position),
+        SyntaxKind::SELF_KW => return rename_to_self(&sema, position),
        _ => return None,
    }
-    let sema = Semantics::new(db);
    let source_file = sema.parse(position.file_id);
    let syntax = source_file.syntax();
    if let Some(module) = find_module_at_offset(&sema, position, syntax) {
-        rename_mod(db, position, module, new_name)
+        rename_mod(&sema, position, module, new_name)
    } else if let Some(self_token) =
        syntax.token_at_offset(position.offset).find(|t| t.kind() == SyntaxKind::SELF_KW)
    {
-        rename_self_to_param(db, position, self_token, new_name)
+        rename_self_to_param(&sema, position, self_token, new_name)
    } else {
-        rename_reference(sema.db, position, new_name)
+        rename_reference(&sema, position, new_name)
    }
 }
@@ -97,7 +98,7 @@ fn source_edit_from_reference(reference: Reference, new_name: &str) -> SourceFil
 }
 fn rename_mod(
-    db: &RootDatabase,
+    sema: &Semantics<RootDatabase>,
    position: FilePosition,
    module: Module,
    new_name: &str,
@@ -105,12 +106,12 @@ fn rename_mod(
    let mut source_file_edits = Vec::new();
    let mut file_system_edits = Vec::new();
-    let src = module.definition_source(db);
+    let src = module.definition_source(sema.db);
-    let file_id = src.file_id.original_file(db);
+    let file_id = src.file_id.original_file(sema.db);
    match src.value {
        ModuleSource::SourceFile(..) => {
            // mod is defined in path/to/dir/mod.rs
-            let dst = if module.is_mod_rs(db) {
+            let dst = if module.is_mod_rs(sema.db) {
                format!("../{}/mod.rs", new_name)
            } else {
                format!("{}.rs", new_name)
@@ -122,17 +123,17 @@ fn rename_mod(
        ModuleSource::Module(..) => {}
    }
-    if let Some(src) = module.declaration_source(db) {
+    if let Some(src) = module.declaration_source(sema.db) {
-        let file_id = src.file_id.original_file(db);
+        let file_id = src.file_id.original_file(sema.db);
        let name = src.value.name()?;
        let edit = SourceFileEdit {
-            file_id: file_id,
+            file_id,
            edit: TextEdit::replace(name.syntax().text_range(), new_name.into()),
        };
        source_file_edits.push(edit);
    }
-    let RangeInfo { range, info: refs } = find_all_refs(db, position, None)?;
+    let RangeInfo { range, info: refs } = find_all_refs(sema, position, None)?;
    let ref_edits = refs
        .references
        .into_iter()
@@ -142,8 +143,10 @@ fn rename_mod(
    Some(RangeInfo::new(range, SourceChange::from_edits(source_file_edits, file_system_edits)))
 }
-fn rename_to_self(db: &RootDatabase, position: FilePosition) -> Option<RangeInfo<SourceChange>> {
+fn rename_to_self(
-    let sema = Semantics::new(db);
+    sema: &Semantics<RootDatabase>,
+    position: FilePosition,
+) -> Option<RangeInfo<SourceChange>> {
    let source_file = sema.parse(position.file_id);
    let syn = source_file.syntax();
@@ -158,7 +161,7 @@ fn rename_to_self(db: &RootDatabase, position: FilePosition) -> Option<RangeInfo
        _ => return None, // not renaming other types
    };
-    let RangeInfo { range, info: refs } = find_all_refs(db, position, None)?;
+    let RangeInfo { range, info: refs } = find_all_refs(sema, position, None)?;
    let param_range = first_param.syntax().text_range();
    let (param_ref, usages): (Vec<Reference>, Vec<Reference>) = refs
@@ -210,16 +213,15 @@ fn text_edit_from_self_param(
 }
 fn rename_self_to_param(
-    db: &RootDatabase,
+    sema: &Semantics<RootDatabase>,
    position: FilePosition,
    self_token: SyntaxToken,
    new_name: &str,
 ) -> Option<RangeInfo<SourceChange>> {
-    let sema = Semantics::new(db);
    let source_file = sema.parse(position.file_id);
    let syn = source_file.syntax();
-    let text = db.file_text(position.file_id);
+    let text = sema.db.file_text(position.file_id);
    let fn_def = find_node_at_offset::<ast::FnDef>(syn, position.offset)?;
    let search_range = fn_def.syntax().text_range();
@@ -249,11 +251,11 @@ fn rename_self_to_param(
 }
 fn rename_reference(
-    db: &RootDatabase,
+    sema: &Semantics<RootDatabase>,
    position: FilePosition,
    new_name: &str,
 ) -> Option<RangeInfo<SourceChange>> {
-    let RangeInfo { range, info: refs } = find_all_refs(db, position, None)?;
+    let RangeInfo { range, info: refs } = find_all_refs(sema, position, None)?;
    let edit = refs
        .into_iter()
diff --git a/crates/ra_ide/src/ssr.rs b/crates/ra_ide/src/ssr.rs
index 9f8e540c0..b3e9e5dfe 100644
--- a/crates/ra_ide/src/ssr.rs
+++ b/crates/ra_ide/src/ssr.rs
@@ -10,6 +10,18 @@ use ra_ssr::{MatchFinder, SsrError, SsrRule};
 // The syntax for a structural search replace command is `<search_pattern> ==>> <replace_pattern>`.
 // A `$<name>` placeholder in the search pattern will match any AST node and `$<name>` will reference it in the replacement.
 // Within a macro call, a placeholder will match up until whatever token follows the placeholder.
+//
+// Placeholders may be given constraints by writing them as `${<name>:<constraint1>:<constraint2>...}`.
+//
+// Supported constraints:
+//
+// |===
+// | Constraint    | Restricts placeholder
+//
+// | kind(literal) | Is a literal (e.g. `42` or `"forty two"`)
+// | not(a)        | Negates the constraint `a`
+// |===
+//
 // Available via the command `rust-analyzer.ssr`.
 //
 // ```rust
diff --git a/crates/ra_ide_db/src/change.rs b/crates/ra_ide_db/src/change.rs
index b507000f2..dbe6eacc5 100644
--- a/crates/ra_ide_db/src/change.rs
+++ b/crates/ra_ide_db/src/change.rs
@@ -243,8 +243,9 @@ impl RootDatabase {
            hir::db::GenericPredicatesForParamQuery
            hir::db::GenericPredicatesQuery
            hir::db::GenericDefaultsQuery
-            hir::db::ImplsInCrateQuery
+            hir::db::InherentImplsInCrateQuery
-            hir::db::ImplsFromDepsQuery
+            hir::db::TraitImplsInCrateQuery
+            hir::db::TraitImplsInDepsQuery
            hir::db::InternTypeCtorQuery
            hir::db::InternTypeParamIdQuery
            hir::db::InternChalkImplQuery
diff --git a/crates/ra_ide_db/src/search.rs b/crates/ra_ide_db/src/search.rs
index 44d5c35e6..81553150b 100644
--- a/crates/ra_ide_db/src/search.rs
+++ b/crates/ra_ide_db/src/search.rs
@@ -180,20 +180,20 @@ impl Definition {
    pub fn find_usages(
        &self,
-        db: &RootDatabase,
+        sema: &Semantics<RootDatabase>,
        search_scope: Option<SearchScope>,
    ) -> Vec<Reference> {
        let _p = profile("Definition::find_usages");
        let search_scope = {
-            let base = self.search_scope(db);
+            let base = self.search_scope(sema.db);
            match search_scope {
                None => base,
                Some(scope) => base.intersection(&scope),
            }
        };
-        let name = match self.name(db) {
+        let name = match self.name(sema.db) {
            None => return Vec::new(),
            Some(it) => it.to_string(),
        };
@@ -202,11 +202,10 @@ impl Definition {
        let mut refs = vec![];
        for (file_id, search_range) in search_scope {
-            let text = db.file_text(file_id);
+            let text = sema.db.file_text(file_id);
            let search_range =
                search_range.unwrap_or(TextRange::up_to(TextSize::of(text.as_str())));
-            let sema = Semantics::new(db);
            let tree = Lazy::new(|| sema.parse(file_id).syntax().clone());
            for (idx, _) in text.match_indices(pat) {
@@ -222,9 +221,6 @@ impl Definition {
                        continue;
                    };
-                // FIXME: reuse sb
-                // See https://github.com/rust-lang/rust/pull/68198#issuecomment-574269098
                match classify_name_ref(&sema, &name_ref) {
                    Some(NameRefClass::Definition(def)) if &def == self => {
                        let kind = if is_record_lit_name_ref(&name_ref)
diff --git a/crates/ra_proc_macro_srv/src/tests/mod.rs b/crates/ra_proc_macro_srv/src/tests/mod.rs
index 82cefbb29..8e6f28abd 100644
--- a/crates/ra_proc_macro_srv/src/tests/mod.rs
+++ b/crates/ra_proc_macro_srv/src/tests/mod.rs
@@ -11,7 +11,7 @@ fn test_derive_serialize_proc_macro() {
        "serde_derive",
        "Serialize",
        "1.0",
-        r##"struct Foo {}"##,
+        r"struct Foo {}",
        include_str!("fixtures/test_serialize_proc_macro.txt"),
    );
 }
@@ -22,9 +22,7 @@ fn test_derive_serialize_proc_macro_failed() {
        "serde_derive",
        "Serialize",
        "1.0",
-        r##"
+        r"struct {}",
-    struct {}
-"##,
        r##"
 SUBTREE $
  IDENT   compile_error 4294967295
diff --git a/crates/ra_proc_macro_srv/src/tests/utils.rs b/crates/ra_proc_macro_srv/src/tests/utils.rs
index 8d85f2d8a..dcb00671f 100644
--- a/crates/ra_proc_macro_srv/src/tests/utils.rs
+++ b/crates/ra_proc_macro_srv/src/tests/utils.rs
@@ -44,12 +44,12 @@ pub fn assert_expand(
    crate_name: &str,
    macro_name: &str,
    version: &str,
-    fixture: &str,
+    ra_fixture: &str,
    expect: &str,
 ) {
    let path = fixtures::dylib_path(crate_name, version);
    let expander = dylib::Expander::new(&path).unwrap();
-    let fixture = parse_string(fixture).unwrap();
+    let fixture = parse_string(ra_fixture).unwrap();
    let res = expander.expand(macro_name, &fixture.subtree, None).unwrap();
    assert_eq_text!(&format!("{:?}", res), &expect.trim());
diff --git a/crates/ra_ssr/Cargo.toml b/crates/ra_ssr/Cargo.toml
index 3c2f15a83..fe098aaee 100644
--- a/crates/ra_ssr/Cargo.toml
+++ b/crates/ra_ssr/Cargo.toml
@@ -17,3 +17,4 @@ ra_db = { path = "../ra_db" }
 ra_ide_db = { path = "../ra_ide_db" }
 hir = { path = "../ra_hir", package = "ra_hir" }
 rustc-hash = "1.1.0"
+test_utils = { path = "../test_utils" }
diff --git a/crates/ra_ssr/src/matching.rs b/crates/ra_ssr/src/matching.rs
index 53d802e77..ce53d46d2 100644
--- a/crates/ra_ssr/src/matching.rs
+++ b/crates/ra_ssr/src/matching.rs
@@ -2,7 +2,7 @@
 //! process of matching, placeholder values are recorded.
 use crate::{
-    parsing::{Placeholder, SsrTemplate},
+    parsing::{Constraint, NodeKind, Placeholder, SsrTemplate},
    SsrMatches, SsrPattern, SsrRule,
 };
 use hir::Semantics;
@@ -11,6 +11,7 @@ use ra_syntax::ast::{AstNode, AstToken};
 use ra_syntax::{ast, SyntaxElement, SyntaxElementChildren, SyntaxKind, SyntaxNode, SyntaxToken};
 use rustc_hash::FxHashMap;
 use std::{cell::Cell, iter::Peekable};
+use test_utils::mark;
 // Creates a match error. If we're currently attempting to match some code that we thought we were
 // going to match, as indicated by the --debug-snippet flag, then populate the reason field.
@@ -169,6 +170,9 @@ impl<'db, 'sema> MatchState<'db, 'sema> {
        if let Some(placeholder) =
            match_inputs.get_placeholder(&SyntaxElement::Node(pattern.clone()))
        {
+            for constraint in &placeholder.constraints {
+                self.check_constraint(constraint, code)?;
+            }
            if self.match_out.is_none() {
                return Ok(());
            }
@@ -292,6 +296,24 @@ impl<'db, 'sema> MatchState<'db, 'sema> {
        Ok(())
    }
+    fn check_constraint(
+        &self,
+        constraint: &Constraint,
+        code: &SyntaxNode,
+    ) -> Result<(), MatchFailed> {
+        match constraint {
+            Constraint::Kind(kind) => {
+                kind.matches(code)?;
+            }
+            Constraint::Not(sub) => {
+                if self.check_constraint(&*sub, code).is_ok() {
+                    fail_match!("Constraint {:?} failed for '{}'", constraint, code.text());
+                }
+            }
+        }
+        Ok(())
+    }
    /// We want to allow the records to match in any order, so we have special matching logic for
    /// them.
    fn attempt_match_record_field_list(
@@ -515,6 +537,21 @@ impl SsrPattern {
    }
 }
+impl NodeKind {
+    fn matches(&self, node: &SyntaxNode) -> Result<(), MatchFailed> {
+        let ok = match self {
+            Self::Literal => {
+                mark::hit!(literal_constraint);
+                ast::Literal::can_cast(node.kind())
+            }
+        };
+        if !ok {
+            fail_match!("Code '{}' isn't of kind {:?}", node.text(), self);
+        }
+        Ok(())
+    }
+}
 // If `node` contains nothing but an ident then return it, otherwise return None.
 fn only_ident(element: SyntaxElement) -> Option<SyntaxToken> {
    match element {
diff --git a/crates/ra_ssr/src/parsing.rs b/crates/ra_ssr/src/parsing.rs
index 04d46bd32..5ea125616 100644
--- a/crates/ra_ssr/src/parsing.rs
+++ b/crates/ra_ssr/src/parsing.rs
@@ -6,7 +6,7 @@
 //! e.g. expressions, type references etc.
 use crate::{SsrError, SsrPattern, SsrRule};
-use ra_syntax::{ast, AstNode, SmolStr, SyntaxKind};
+use ra_syntax::{ast, AstNode, SmolStr, SyntaxKind, T};
 use rustc_hash::{FxHashMap, FxHashSet};
 use std::str::FromStr;
@@ -39,6 +39,18 @@ pub(crate) struct Placeholder {
    pub(crate) ident: SmolStr,
    /// A unique name used in place of this placeholder when we parse the pattern as Rust code.
    stand_in_name: String,
+    pub(crate) constraints: Vec<Constraint>,
+}
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) enum Constraint {
+    Kind(NodeKind),
+    Not(Box<Constraint>),
+}
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub(crate) enum NodeKind {
+    Literal,
 }
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -149,7 +161,7 @@ fn parse_pattern(pattern_str: &str) -> Result<Vec<PatternElement>, SsrError> {
    let mut placeholder_names = FxHashSet::default();
    let mut tokens = tokenize(pattern_str)?.into_iter();
    while let Some(token) = tokens.next() {
-        if token.kind == SyntaxKind::DOLLAR {
+        if token.kind == T![$] {
            let placeholder = parse_placeholder(&mut tokens)?;
            if !placeholder_names.insert(placeholder.ident.clone()) {
                bail!("Name `{}` repeats more than once", placeholder.ident);
@@ -177,6 +189,9 @@ fn validate_rule(rule: &SsrRule) -> Result<(), SsrError> {
            if !defined_placeholders.contains(&placeholder.ident) {
                undefined.push(format!("${}", placeholder.ident));
            }
+            if !placeholder.constraints.is_empty() {
+                bail!("Replacement placeholders cannot have constraints");
+            }
        }
    }
    if !undefined.is_empty() {
@@ -205,23 +220,90 @@ fn tokenize(source: &str) -> Result<Vec<Token>, SsrError> {
 fn parse_placeholder(tokens: &mut std::vec::IntoIter<Token>) -> Result<Placeholder, SsrError> {
    let mut name = None;
+    let mut constraints = Vec::new();
    if let Some(token) = tokens.next() {
        match token.kind {
            SyntaxKind::IDENT => {
                name = Some(token.text);
            }
+            T!['{'] => {
+                let token =
+                    tokens.next().ok_or_else(|| SsrError::new("Unexpected end of placeholder"))?;
+                if token.kind == SyntaxKind::IDENT {
+                    name = Some(token.text);
+                }
+                loop {
+                    let token = tokens
+                        .next()
+                        .ok_or_else(|| SsrError::new("Placeholder is missing closing brace '}'"))?;
+                    match token.kind {
+                        T![:] => {
+                            constraints.push(parse_constraint(tokens)?);
+                        }
+                        T!['}'] => break,
+                        _ => bail!("Unexpected token while parsing placeholder: '{}'", token.text),
+                    }
+                }
+            }
            _ => {
-                bail!("Placeholders should be $name");
+                bail!("Placeholders should either be $name or ${name:constraints}");
            }
        }
    }
    let name = name.ok_or_else(|| SsrError::new("Placeholder ($) with no name"))?;
-    Ok(Placeholder::new(name))
+    Ok(Placeholder::new(name, constraints))
+}
+fn parse_constraint(tokens: &mut std::vec::IntoIter<Token>) -> Result<Constraint, SsrError> {
+    let constraint_type = tokens
+        .next()
+        .ok_or_else(|| SsrError::new("Found end of placeholder while looking for a constraint"))?
+        .text
+        .to_string();
+    match constraint_type.as_str() {
+        "kind" => {
+            expect_token(tokens, "(")?;
+            let t = tokens.next().ok_or_else(|| {
+                SsrError::new("Unexpected end of constraint while looking for kind")
+            })?;
+            if t.kind != SyntaxKind::IDENT {
+                bail!("Expected ident, found {:?} while parsing kind constraint", t.kind);
+            }
+            expect_token(tokens, ")")?;
+            Ok(Constraint::Kind(NodeKind::from(&t.text)?))
+        }
+        "not" => {
+            expect_token(tokens, "(")?;
+            let sub = parse_constraint(tokens)?;
+            expect_token(tokens, ")")?;
+            Ok(Constraint::Not(Box::new(sub)))
+        }
+        x => bail!("Unsupported constraint type '{}'", x),
+    }
+}
+fn expect_token(tokens: &mut std::vec::IntoIter<Token>, expected: &str) -> Result<(), SsrError> {
+    if let Some(t) = tokens.next() {
+        if t.text == expected {
+            return Ok(());
+        }
+        bail!("Expected {} found {}", expected, t.text);
+    }
+    bail!("Expected {} found end of stream");
+}
+impl NodeKind {
+    fn from(name: &SmolStr) -> Result<NodeKind, SsrError> {
+        Ok(match name.as_str() {
+            "literal" => NodeKind::Literal,
+            _ => bail!("Unknown node kind '{}'", name),
+        })
+    }
 }
 impl Placeholder {
-    fn new(name: SmolStr) -> Self {
+    fn new(name: SmolStr, constraints: Vec<Constraint>) -> Self {
-        Self { stand_in_name: format!("__placeholder_{}", name), ident: name }
+        Self { stand_in_name: format!("__placeholder_{}", name), constraints, ident: name }
    }
 }
@@ -241,31 +323,31 @@ mod tests {
            PatternElement::Token(Token { kind, text: SmolStr::new(text) })
        }
        fn placeholder(name: &str) -> PatternElement {
-            PatternElement::Placeholder(Placeholder::new(SmolStr::new(name)))
+            PatternElement::Placeholder(Placeholder::new(SmolStr::new(name), Vec::new()))
        }
        let result: SsrRule = "foo($a, $b) ==>> bar($b, $a)".parse().unwrap();
        assert_eq!(
            result.pattern.raw.tokens,
            vec![
                token(SyntaxKind::IDENT, "foo"),
-                token(SyntaxKind::L_PAREN, "("),
+                token(T!['('], "("),
                placeholder("a"),
-                token(SyntaxKind::COMMA, ","),
+                token(T![,], ","),
                token(SyntaxKind::WHITESPACE, " "),
                placeholder("b"),
-                token(SyntaxKind::R_PAREN, ")"),
+                token(T![')'], ")"),
            ]
        );
        assert_eq!(
            result.template.tokens,
            vec![
                token(SyntaxKind::IDENT, "bar"),
-                token(SyntaxKind::L_PAREN, "("),
+                token(T!['('], "("),
                placeholder("b"),
-                token(SyntaxKind::COMMA, ","),
+                token(T![,], ","),
                token(SyntaxKind::WHITESPACE, " "),
                placeholder("a"),
-                token(SyntaxKind::R_PAREN, ")"),
+                token(T![')'], ")"),
            ]
        );
    }
diff --git a/crates/ra_ssr/src/tests.rs b/crates/ra_ssr/src/tests.rs
index c692c97e2..9568d4432 100644
--- a/crates/ra_ssr/src/tests.rs
+++ b/crates/ra_ssr/src/tests.rs
@@ -1,5 +1,6 @@
 use crate::{MatchFinder, SsrRule};
 use ra_db::{FileId, SourceDatabaseExt};
+use test_utils::mark;
 fn parse_error_text(query: &str) -> String {
    format!("{}", query.parse::<SsrRule>().unwrap_err())
@@ -302,6 +303,22 @@ fn match_pattern() {
 }
 #[test]
+fn literal_constraint() {
+    mark::check!(literal_constraint);
+    let code = r#"
+        fn f1() {
+            let x1 = Some(42);
+            let x2 = Some("foo");
+            let x3 = Some(x1);
+            let x4 = Some(40 + 2);
+            let x5 = Some(true);
+        }
+        "#;
+    assert_matches("Some(${a:kind(literal)})", code, &["Some(42)", "Some(\"foo\")", "Some(true)"]);
+    assert_matches("Some(${a:not(kind(literal))})", code, &["Some(x1)", "Some(40 + 2)"]);
+}
+#[test]
 fn match_reordered_struct_instantiation() {
    assert_matches(
        "Foo {aa: 1, b: 2, ccc: 3}",
diff --git a/crates/rust-analyzer/src/to_proto.rs b/crates/rust-analyzer/src/to_proto.rs
index a0a58f689..95dd8e408 100644
--- a/crates/rust-analyzer/src/to_proto.rs
+++ b/crates/rust-analyzer/src/to_proto.rs
@@ -352,7 +352,7 @@ pub(crate) fn folding_range(
    let kind = match fold.kind {
        FoldKind::Comment => Some(lsp_types::FoldingRangeKind::Comment),
        FoldKind::Imports => Some(lsp_types::FoldingRangeKind::Imports),
-        FoldKind::Mods | FoldKind::Block => None,
+        FoldKind::Mods | FoldKind::Block | FoldKind::ArgList => None,
    };
    let range = range(line_index, fold.range);
@@ -685,32 +685,27 @@ pub(crate) fn runnable(
 #[cfg(test)]
 mod tests {
-    use test_utils::extract_ranges;
+    use ra_ide::Analysis;
    use super::*;
    #[test]
    fn conv_fold_line_folding_only_fixup() {
-        let text = r#"<fold>mod a;
+        let text = r#"mod a;
 mod b;
-mod c;</fold>
+mod c;
-fn main() <fold>{
+fn main() {
-    if cond <fold>{
+    if cond {
        a::do_a();
-    }</fold> else <fold>{
+    } else {
        b::do_b();
-    }</fold>
+    }
-}</fold>"#;
+}"#;
-        let (ranges, text) = extract_ranges(text, "fold");
+        let (analysis, file_id) = Analysis::from_single_file(text.to_string());
-        assert_eq!(ranges.len(), 4);
+        let folds = analysis.folding_ranges(file_id).unwrap();
-        let folds = vec![
+        assert_eq!(folds.len(), 4);
-            Fold { range: ranges[0], kind: FoldKind::Mods },
-            Fold { range: ranges[1], kind: FoldKind::Block },
-            Fold { range: ranges[2], kind: FoldKind::Block },
-            Fold { range: ranges[3], kind: FoldKind::Block },
-        ];
        let line_index = LineIndex::new(&text);
        let converted: Vec<lsp_types::FoldingRange> =
diff --git a/crates/test_utils/src/lib.rs b/crates/test_utils/src/lib.rs
index fba5f4281..e4aa894ac 100644
--- a/crates/test_utils/src/lib.rs
+++ b/crates/test_utils/src/lib.rs
@@ -118,8 +118,8 @@ pub fn extract_range_or_offset(text: &str) -> (RangeOrOffset, String) {
 }
 /// Extracts ranges, marked with `<tag> </tag>` pairs from the `text`
-pub fn extract_ranges(mut text: &str, tag: &str) -> (Vec<TextRange>, String) {
+pub fn extract_tags(mut text: &str, tag: &str) -> (Vec<(TextRange, Option<String>)>, String) {
-    let open = format!("<{}>", tag);
+    let open = format!("<{}", tag);
    let close = format!("</{}>", tag);
    let mut ranges = Vec::new();
    let mut res = String::new();
@@ -134,22 +134,35 @@ pub fn extract_ranges(mut text: &str, tag: &str) -> (Vec<TextRange>, String) {
                res.push_str(&text[..i]);
                text = &text[i..];
                if text.starts_with(&open) {
-                    text = &text[open.len()..];
+                    let close_open = text.find('>').unwrap();
+                    let attr = text[open.len()..close_open].trim();
+                    let attr = if attr.is_empty() { None } else { Some(attr.to_string()) };
+                    text = &text[close_open + '>'.len_utf8()..];
                    let from = TextSize::of(&res);
-                    stack.push(from);
+                    stack.push((from, attr));
                } else if text.starts_with(&close) {
                    text = &text[close.len()..];
-                    let from = stack.pop().unwrap_or_else(|| panic!("unmatched </{}>", tag));
+                    let (from, attr) =
+                        stack.pop().unwrap_or_else(|| panic!("unmatched </{}>", tag));
                    let to = TextSize::of(&res);
-                    ranges.push(TextRange::new(from, to));
+                    ranges.push((TextRange::new(from, to), attr));
+                } else {
+                    res.push('<');
+                    text = &text['<'.len_utf8()..];
                }
            }
        }
    }
    assert!(stack.is_empty(), "unmatched <{}>", tag);
-    ranges.sort_by_key(|r| (r.start(), r.end()));
+    ranges.sort_by_key(|r| (r.0.start(), r.0.end()));
    (ranges, res)
 }
+#[test]
+fn test_extract_tags() {
+    let (tags, text) = extract_tags(r#"<tag fn>fn <tag>main</tag>() {}</tag>"#, "tag");
+    let actual = tags.into_iter().map(|(range, attr)| (&text[range], attr)).collect::<Vec<_>>();
+    assert_eq!(actual, vec![("fn main() {}", Some("fn".into())), ("main", None),]);
+}
 /// Inserts `<|>` marker into the `text` at `offset`.
 pub fn add_cursor(text: &str, offset: TextSize) -> String {
diff --git a/editors/code/src/main.ts b/editors/code/src/main.ts
index 2982b9cbf..a1521a93b 100644
--- a/editors/code/src/main.ts
+++ b/editors/code/src/main.ts
@@ -19,6 +19,16 @@ let ctx: Ctx | undefined;
 const RUST_PROJECT_CONTEXT_NAME = "inRustProject";
 export async function activate(context: vscode.ExtensionContext) {
+    // For some reason vscode not always shows pop-up error notifications
+    // when an extension fails to activate, so we do it explicitly by ourselves.
+    // FIXME: remove this bit of code once vscode fixes this issue: https://github.com/microsoft/vscode/issues/101242
+    await tryActivate(context).catch(err => {
+        void vscode.window.showErrorMessage(`Cannot activate rust-analyzer: ${err.message}`);
+        throw err;
+    });
+}
+async function tryActivate(context: vscode.ExtensionContext) {
    // Register a "dumb" onEnter command for the case where server fails to
    // start.
    //
@@ -58,9 +68,7 @@ export async function activate(context: vscode.ExtensionContext) {
    const workspaceFolder = vscode.workspace.workspaceFolders?.[0];
    if (workspaceFolder === undefined) {
-        const err = "Cannot activate rust-analyzer when no folder is opened";
+        throw new Error("no folder is opened");
-        void vscode.window.showErrorMessage(err);
-        throw new Error(err);
    }
    // Note: we try to start the server before we activate type hints so that it
@@ -152,13 +160,17 @@ async function bootstrapExtension(config: Config, state: PersistentState): Promi
        return;
    };
-    const lastCheck = state.lastCheck;
    const now = Date.now();
+    if (config.package.releaseTag === NIGHTLY_TAG) {
+        // Check if we should poll github api for the new nightly version
+        // if we haven't done it during the past hour
+        const lastCheck = state.lastCheck;
-    const anHour = 60 * 60 * 1000;
+        const anHour = 60 * 60 * 1000;
-    const shouldDownloadNightly = state.releaseId === undefined || (now - (lastCheck ?? 0)) > anHour;
+        const shouldCheckForNewNightly = state.releaseId === undefined || (now - (lastCheck ?? 0)) > anHour;
-    if (!shouldDownloadNightly) return;
+        if (!shouldCheckForNewNightly) return;
+    }
    const release = await fetchRelease("nightly").catch((e) => {
        log.error(e);