11 files changed, 96 insertions, 117 deletions

diff --git a/crates/ra_hir/src/code_model.rs b/crates/ra_hir/src/code_model.rs
index 92860fb59..5690040a7 100644
--- a/crates/ra_hir/src/code_model.rs
+++ b/crates/ra_hir/src/code_model.rs
@@ -27,7 +27,6 @@ use ra_syntax::ast::{self, NameOwner, TypeAscriptionOwner};
 use crate::{
     db::{AstDatabase, DefDatabase, HirDatabase},
     expr::{BindingAnnotation, Body, BodySourceMap, ExprValidator, Pat, PatId},
-    generics::{GenericDef, HasGenericParams},
     ids::{
         AstItemDef, ConstId, EnumId, FunctionId, MacroDefId, StaticId, StructId, TraitId,
         TypeAliasId,
@@ -835,7 +834,7 @@ impl Trait {
         // lifetime problems, but since there usually shouldn't be more than a
         // few direct traits this should be fine (we could even use some kind of
         // SmallVec if performance is a concern)
-        self.generic_params(db)
+        db.generic_params(self.id.into())
             .where_predicates
             .iter()
             .filter_map(|pred| match &pred.type_ref {
@@ -975,16 +974,6 @@ pub enum AssocItem {
 // casting them, and somehow making the constructors private, which would be annoying.
 impl_froms!(AssocItem: Function, Const, TypeAlias);
 
-impl From<AssocItem> for crate::generics::GenericDef {
-    fn from(item: AssocItem) -> Self {
-        match item {
-            AssocItem::Function(f) => f.into(),
-            AssocItem::Const(c) => c.into(),
-            AssocItem::TypeAlias(t) => t.into(),
-        }
-    }
-}
-
 impl AssocItem {
     pub fn module(self, db: &impl DefDatabase) -> Module {
         match self {
@@ -1004,6 +993,39 @@ impl AssocItem {
     }
 }
 
+#[derive(Clone, Copy, PartialEq, Eq, Debug, Hash)]
+pub enum GenericDef {
+    Function(Function),
+    Adt(Adt),
+    Trait(Trait),
+    TypeAlias(TypeAlias),
+    ImplBlock(ImplBlock),
+    // enum variants cannot have generics themselves, but their parent enums
+    // can, and this makes some code easier to write
+    EnumVariant(EnumVariant),
+    // consts can have type parameters from their parents (i.e. associated consts of traits)
+    Const(Const),
+}
+impl_froms!(
+    GenericDef: Function,
+    Adt(Struct, Enum, Union),
+    Trait,
+    TypeAlias,
+    ImplBlock,
+    EnumVariant,
+    Const
+);
+
+impl From<AssocItem> for GenericDef {
+    fn from(item: AssocItem) -> Self {
+        match item {
+            AssocItem::Function(f) => f.into(),
+            AssocItem::Const(c) => c.into(),
+            AssocItem::TypeAlias(t) => t.into(),
+        }
+    }
+}
+
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub struct Local {
     pub(crate) parent: DefWithBody,
diff --git a/crates/ra_hir/src/db.rs b/crates/ra_hir/src/db.rs
index a9982a70f..ed0d68001 100644
--- a/crates/ra_hir/src/db.rs
+++ b/crates/ra_hir/src/db.rs
@@ -8,7 +8,6 @@ use ra_syntax::SmolStr;
 
 use crate::{
     debug::HirDebugDatabase,
-    generics::GenericDef,
     ids,
     lang_item::{LangItemTarget, LangItems},
     ty::{
@@ -18,8 +17,8 @@ use crate::{
         TypeCtor,
     },
     type_alias::TypeAliasData,
-    Const, ConstData, Crate, DefWithBody, FnData, Function, ImplBlock, Module, Static, StructField,
-    Trait, TypeAlias,
+    Const, ConstData, Crate, DefWithBody, FnData, Function, GenericDef, ImplBlock, Module, Static,
+    StructField, Trait, TypeAlias,
 };
 
 pub use hir_def::db::{
diff --git a/crates/ra_hir/src/from_id.rs b/crates/ra_hir/src/from_id.rs
index a3e9d8525..e8ed04056 100644
--- a/crates/ra_hir/src/from_id.rs
+++ b/crates/ra_hir/src/from_id.rs
@@ -9,8 +9,9 @@ use hir_def::{
 };
 
 use crate::{
-    ty::TypableDef, Adt, AssocItem, Const, Crate, DefWithBody, EnumVariant, Function, GenericDef,
-    ModuleDef, Static, TypeAlias,
+    ty::{CallableDef, TypableDef},
+    Adt, AssocItem, Const, Crate, DefWithBody, EnumVariant, Function, GenericDef, ModuleDef,
+    Static, TypeAlias,
 };
 
 impl From<ra_db::CrateId> for Crate {
@@ -206,3 +207,15 @@ impl From<Adt> for GenericDefId {
         }
     }
 }
+
+impl From<CallableDef> for GenericDefId {
+    fn from(def: CallableDef) -> Self {
+        match def {
+            CallableDef::Function(it) => it.id.into(),
+            CallableDef::Struct(it) => it.id.into(),
+            CallableDef::EnumVariant(it) => {
+                EnumVariantId { parent: it.parent.id, local_id: it.id }.into()
+            }
+        }
+    }
+}
diff --git a/crates/ra_hir/src/generics.rs b/crates/ra_hir/src/generics.rs
deleted file mode 100644
index f1bf2ee9d..000000000
--- a/crates/ra_hir/src/generics.rs
+++ /dev/null
@@ -1,54 +0,0 @@
-//! Temp module to wrap hir_def::generics
-use std::sync::Arc;
-
-use crate::{
-    db::DefDatabase, Adt, Const, Container, Enum, EnumVariant, Function, ImplBlock, Struct, Trait,
-    TypeAlias, Union,
-};
-
-pub use hir_def::generics::{GenericParam, GenericParams, WherePredicate};
-
-#[derive(Clone, Copy, PartialEq, Eq, Debug, Hash)]
-pub enum GenericDef {
-    Function(Function),
-    Adt(Adt),
-    Trait(Trait),
-    TypeAlias(TypeAlias),
-    ImplBlock(ImplBlock),
-    // enum variants cannot have generics themselves, but their parent enums
-    // can, and this makes some code easier to write
-    EnumVariant(EnumVariant),
-    // consts can have type parameters from their parents (i.e. associated consts of traits)
-    Const(Const),
-}
-impl_froms!(
-    GenericDef: Function,
-    Adt(Struct, Enum, Union),
-    Trait,
-    TypeAlias,
-    ImplBlock,
-    EnumVariant,
-    Const
-);
-
-impl From<Container> for GenericDef {
-    fn from(c: Container) -> Self {
-        match c {
-            Container::Trait(trait_) => trait_.into(),
-            Container::ImplBlock(impl_block) => impl_block.into(),
-        }
-    }
-}
-
-pub trait HasGenericParams: Copy {
-    fn generic_params(self, db: &impl DefDatabase) -> Arc<GenericParams>;
-}
-
-impl<T> HasGenericParams for T
-where
-    T: Into<GenericDef> + Copy,
-{
-    fn generic_params(self, db: &impl DefDatabase) -> Arc<GenericParams> {
-        db.generic_params(self.into().into())
-    }
-}
diff --git a/crates/ra_hir/src/lib.rs b/crates/ra_hir/src/lib.rs
index 76c96bdcf..8c6834392 100644
--- a/crates/ra_hir/src/lib.rs
+++ b/crates/ra_hir/src/lib.rs
@@ -37,7 +37,6 @@ mod ty;
 mod impl_block;
 mod expr;
 mod lang_item;
-pub mod generics;
 pub mod diagnostics;
 mod util;
 
@@ -57,13 +56,12 @@ pub use crate::{
         docs::{DocDef, Docs, Documentation},
         src::{HasBodySource, HasSource},
         Adt, AssocItem, Const, ConstData, Container, Crate, CrateDependency, DefWithBody, Enum,
-        EnumVariant, FieldSource, FnData, Function, GenericParam, HasBody, ImplBlock, Local,
-        MacroDef, Module, ModuleDef, ModuleSource, ScopeDef, Static, Struct, StructField, Trait,
-        TypeAlias, Union, VariantDef,
+        EnumVariant, FieldSource, FnData, Function, GenericDef, GenericParam, HasBody, ImplBlock,
+        Local, MacroDef, Module, ModuleDef, ModuleSource, ScopeDef, Static, Struct, StructField,
+        Trait, TypeAlias, Union, VariantDef,
     },
     expr::ExprScopes,
     from_source::FromSource,
-    generics::GenericDef,
     ids::{HirFileId, MacroCallId, MacroCallLoc, MacroDefId, MacroFile},
     source_binder::{PathResolution, ScopeEntryWithSyntax, SourceAnalyzer},
     ty::{
diff --git a/crates/ra_hir/src/ty.rs b/crates/ra_hir/src/ty.rs
index 36ece723f..95b8df181 100644
--- a/crates/ra_hir/src/ty.rs
+++ b/crates/ra_hir/src/ty.rs
@@ -17,12 +17,11 @@ use std::ops::Deref;
 use std::sync::Arc;
 use std::{fmt, iter, mem};
 
+use hir_def::{generics::GenericParams, AdtId};
+
 use crate::{
-    db::HirDatabase,
-    expr::ExprId,
-    generics::{GenericParams, HasGenericParams},
-    util::make_mut_slice,
-    Adt, Crate, DefWithBody, FloatTy, IntTy, Mutability, Name, Trait, TypeAlias, Uncertain,
+    db::HirDatabase, expr::ExprId, util::make_mut_slice, Adt, Crate, DefWithBody, FloatTy,
+    GenericDef, IntTy, Mutability, Name, Trait, TypeAlias, Uncertain,
 };
 use display::{HirDisplay, HirFormatter};
 
@@ -131,15 +130,15 @@ impl TypeCtor {
             | TypeCtor::Closure { .. } // 1 param representing the signature of the closure
             => 1,
             TypeCtor::Adt(adt) => {
-                let generic_params = adt.generic_params(db);
+                let generic_params = db.generic_params(AdtId::from(adt).into());
                 generic_params.count_params_including_parent()
             }
             TypeCtor::FnDef(callable) => {
-                let generic_params = callable.generic_params(db);
+                let generic_params = db.generic_params(callable.into());
                 generic_params.count_params_including_parent()
             }
             TypeCtor::AssociatedType(type_alias) => {
-                let generic_params = type_alias.generic_params(db);
+                let generic_params = db.generic_params(type_alias.id.into());
                 generic_params.count_params_including_parent()
             }
             TypeCtor::FnPtr { num_args } => num_args as usize + 1,
@@ -168,7 +167,7 @@ impl TypeCtor {
         }
     }
 
-    pub fn as_generic_def(self) -> Option<crate::generics::GenericDef> {
+    pub fn as_generic_def(self) -> Option<crate::GenericDef> {
         match self {
             TypeCtor::Bool
             | TypeCtor::Char
@@ -348,8 +347,9 @@ impl Substs {
         )
     }
 
-    pub fn build_for_def(db: &impl HirDatabase, def: impl HasGenericParams) -> SubstsBuilder {
-        let params = def.generic_params(db);
+    pub fn build_for_def(db: &impl HirDatabase, def: impl Into<GenericDef>) -> SubstsBuilder {
+        let def = def.into();
+        let params = db.generic_params(def.into());
         let param_count = params.count_params_including_parent();
         Substs::builder(param_count)
     }
diff --git a/crates/ra_hir/src/ty/autoderef.rs b/crates/ra_hir/src/ty/autoderef.rs
index 5d8518041..b60e4bb31 100644
--- a/crates/ra_hir/src/ty/autoderef.rs
+++ b/crates/ra_hir/src/ty/autoderef.rs
@@ -10,7 +10,7 @@ use hir_expand::name;
 use log::{info, warn};
 
 use super::{traits::Solution, Canonical, Substs, Ty, TypeWalk};
-use crate::{db::HirDatabase, generics::HasGenericParams};
+use crate::db::HirDatabase;
 
 const AUTODEREF_RECURSION_LIMIT: usize = 10;
 
@@ -46,7 +46,7 @@ fn deref_by_trait(
     };
     let target = deref_trait.associated_type_by_name(db, &name::TARGET_TYPE)?;
 
-    let generic_params = target.generic_params(db);
+    let generic_params = db.generic_params(target.id.into());
     if generic_params.count_params_including_parent() != 1 {
         // the Target type + Deref trait should only have one generic parameter,
         // namely Deref's Self type
diff --git a/crates/ra_hir/src/ty/infer/expr.rs b/crates/ra_hir/src/ty/infer/expr.rs
index ac570075f..20a7e9352 100644
--- a/crates/ra_hir/src/ty/infer/expr.rs
+++ b/crates/ra_hir/src/ty/infer/expr.rs
@@ -5,6 +5,7 @@ use std::sync::Arc;
 
 use hir_def::{
     builtin_type::Signedness,
+    generics::GenericParams,
     path::{GenericArg, GenericArgs},
     resolver::resolver_for_expr,
 };
@@ -13,7 +14,6 @@ use hir_expand::name;
 use crate::{
     db::HirDatabase,
     expr::{Array, BinaryOp, Expr, ExprId, Literal, Statement, UnaryOp},
-    generics::{GenericParams, HasGenericParams},
     ty::{
         autoderef, method_resolution, op, CallableDef, InferTy, IntTy, Mutability, Namespace,
         Obligation, ProjectionPredicate, ProjectionTy, Substs, TraitRef, Ty, TypeCtor, TypeWalk,
@@ -534,7 +534,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
                 (
                     ty,
                     self.db.type_for_def(func.into(), Namespace::Values),
-                    Some(func.generic_params(self.db)),
+                    Some(self.db.generic_params(func.id.into())),
                 )
             }
             None => (receiver_ty, Ty::Unknown, None),
@@ -645,7 +645,9 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
                         if let Some(trait_) = f.parent_trait(self.db) {
                             // construct a TraitDef
                             let substs = a_ty.parameters.prefix(
-                                trait_.generic_params(self.db).count_params_including_parent(),
+                                self.db
+                                    .generic_params(trait_.id.into())
+                                    .count_params_including_parent(),
                             );
                             self.obligations.push(Obligation::Trait(TraitRef { trait_, substs }));
                         }
diff --git a/crates/ra_hir/src/ty/infer/path.rs b/crates/ra_hir/src/ty/infer/path.rs
index 70136e514..ee54d8217 100644
--- a/crates/ra_hir/src/ty/infer/path.rs
+++ b/crates/ra_hir/src/ty/infer/path.rs
@@ -7,7 +7,6 @@ use hir_def::{
 
 use crate::{
     db::HirDatabase,
-    generics::HasGenericParams,
     ty::{method_resolution, Namespace, Substs, Ty, TypableDef, TypeWalk},
     AssocItem, Container, Function, Name, Path,
 };
@@ -230,7 +229,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
         if let ValueNs::FunctionId(func) = def {
             let func = Function::from(*func);
             // We only do the infer if parent has generic params
-            let gen = func.generic_params(self.db);
+            let gen = self.db.generic_params(func.id.into());
             if gen.count_parent_params() == 0 {
                 return None;
             }
diff --git a/crates/ra_hir/src/ty/lower.rs b/crates/ra_hir/src/ty/lower.rs
index c6ad0811b..75c552569 100644
--- a/crates/ra_hir/src/ty/lower.rs
+++ b/crates/ra_hir/src/ty/lower.rs
@@ -10,10 +10,11 @@ use std::sync::Arc;
 
 use hir_def::{
     builtin_type::{BuiltinFloat, BuiltinInt, BuiltinType},
+    generics::WherePredicate,
     path::{GenericArg, PathSegment},
     resolver::{HasResolver, Resolver, TypeNs},
     type_ref::{TypeBound, TypeRef},
-    GenericDefId,
+    AdtId, GenericDefId,
 };
 
 use super::{
@@ -22,15 +23,13 @@ use super::{
 };
 use crate::{
     db::HirDatabase,
-    generics::HasGenericParams,
-    generics::{GenericDef, WherePredicate},
     ty::{
         primitive::{FloatTy, IntTy, Uncertain},
         Adt,
     },
     util::make_mut_slice,
-    Const, Enum, EnumVariant, Function, ImplBlock, ModuleDef, Path, Static, Struct, StructField,
-    Trait, TypeAlias, Union, VariantDef,
+    Const, Enum, EnumVariant, Function, GenericDef, ImplBlock, ModuleDef, Path, Static, Struct,
+    StructField, Trait, TypeAlias, Union, VariantDef,
 };
 
 // FIXME: this is only really used in `type_for_def`, which contains a bunch of
@@ -342,7 +341,7 @@ pub(super) fn substs_from_path_segment(
     add_self_param: bool,
 ) -> Substs {
     let mut substs = Vec::new();
-    let def_generics = def_generic.map(|def| def.generic_params(db));
+    let def_generics = def_generic.map(|def| db.generic_params(def.into()));
 
     let (parent_param_count, param_count) =
         def_generics.map_or((0, 0), |g| (g.count_parent_params(), g.params.len()));
@@ -443,7 +442,7 @@ impl TraitRef {
     }
 
     pub(crate) fn for_trait(db: &impl HirDatabase, trait_: Trait) -> TraitRef {
-        let substs = Substs::identity(&trait_.generic_params(db));
+        let substs = Substs::identity(&db.generic_params(trait_.id.into()));
         TraitRef { trait_, substs }
     }
 
@@ -611,7 +610,7 @@ pub(crate) fn generic_predicates_query(
 /// Resolve the default type params from generics
 pub(crate) fn generic_defaults_query(db: &impl HirDatabase, def: GenericDef) -> Substs {
     let resolver = GenericDefId::from(def).resolver(db);
-    let generic_params = def.generic_params(db);
+    let generic_params = db.generic_params(def.into());
 
     let defaults = generic_params
         .params_including_parent()
@@ -633,7 +632,7 @@ fn fn_sig_for_fn(db: &impl HirDatabase, def: Function) -> FnSig {
 /// Build the declared type of a function. This should not need to look at the
 /// function body.
 fn type_for_fn(db: &impl HirDatabase, def: Function) -> Ty {
-    let generics = def.generic_params(db);
+    let generics = db.generic_params(def.id.into());
     let substs = Substs::identity(&generics);
     Ty::apply(TypeCtor::FnDef(def.into()), substs)
 }
@@ -716,7 +715,7 @@ fn type_for_struct_constructor(db: &impl HirDatabase, def: Struct) -> Ty {
     if struct_data.variant_data.fields().is_none() {
         return type_for_adt(db, def); // Unit struct
     }
-    let generics = def.generic_params(db);
+    let generics = db.generic_params(def.id.into());
     let substs = Substs::identity(&generics);
     Ty::apply(TypeCtor::FnDef(def.into()), substs)
 }
@@ -732,7 +731,7 @@ fn fn_sig_for_enum_variant_constructor(db: &impl HirDatabase, def: EnumVariant)
         .iter()
         .map(|(_, field)| Ty::from_hir(db, &resolver, &field.type_ref))
         .collect::<Vec<_>>();
-    let generics = def.parent_enum(db).generic_params(db);
+    let generics = db.generic_params(def.parent_enum(db).id.into());
     let substs = Substs::identity(&generics);
     let ret = type_for_adt(db, def.parent_enum(db)).subst(&substs);
     FnSig::from_params_and_return(params, ret)
@@ -744,18 +743,20 @@ fn type_for_enum_variant_constructor(db: &impl HirDatabase, def: EnumVariant) ->
     if var_data.fields().is_none() {
         return type_for_adt(db, def.parent_enum(db)); // Unit variant
     }
-    let generics = def.parent_enum(db).generic_params(db);
+    let generics = db.generic_params(def.parent_enum(db).id.into());
     let substs = Substs::identity(&generics);
     Ty::apply(TypeCtor::FnDef(def.into()), substs)
 }
 
-fn type_for_adt(db: &impl HirDatabase, adt: impl Into<Adt> + HasGenericParams) -> Ty {
-    let generics = adt.generic_params(db);
-    Ty::apply(TypeCtor::Adt(adt.into()), Substs::identity(&generics))
+fn type_for_adt(db: &impl HirDatabase, adt: impl Into<Adt>) -> Ty {
+    let adt = adt.into();
+    let adt_id: AdtId = adt.into();
+    let generics = db.generic_params(adt_id.into());
+    Ty::apply(TypeCtor::Adt(adt), Substs::identity(&generics))
 }
 
 fn type_for_type_alias(db: &impl HirDatabase, t: TypeAlias) -> Ty {
-    let generics = t.generic_params(db);
+    let generics = db.generic_params(t.id.into());
     let resolver = t.id.resolver(db);
     let type_ref = t.type_ref(db);
     let substs = Substs::identity(&generics);
diff --git a/crates/ra_hir/src/ty/traits/chalk.rs b/crates/ra_hir/src/ty/traits/chalk.rs
index 9bf93981a..88785f305 100644
--- a/crates/ra_hir/src/ty/traits/chalk.rs
+++ b/crates/ra_hir/src/ty/traits/chalk.rs
@@ -16,10 +16,9 @@ use ra_db::salsa::{InternId, InternKey};
 use super::{AssocTyValue, Canonical, ChalkContext, Impl, Obligation};
 use crate::{
     db::HirDatabase,
-    generics::{GenericDef, HasGenericParams},
     ty::display::HirDisplay,
     ty::{ApplicationTy, GenericPredicate, ProjectionTy, Substs, TraitRef, Ty, TypeCtor, TypeWalk},
-    Crate, HasBody, ImplBlock, Trait, TypeAlias,
+    Crate, GenericDef, HasBody, ImplBlock, Trait, TypeAlias,
 };
 
 /// This represents a trait whose name we could not resolve.
@@ -509,7 +508,7 @@ pub(crate) fn associated_ty_data_query(
         Some(crate::Container::Trait(t)) => t,
         _ => panic!("associated type not in trait"),
     };
-    let generic_params = type_alias.generic_params(db);
+    let generic_params = db.generic_params(type_alias.id.into());
     let bound_data = chalk_rust_ir::AssociatedTyDatumBound {
         // FIXME add bounds and where clauses
         bounds: vec![],
@@ -550,7 +549,7 @@ pub(crate) fn trait_datum_query(
     }
     let trait_: Trait = from_chalk(db, trait_id);
     debug!("trait {:?} = {:?}", trait_id, trait_.name(db));
-    let generic_params = trait_.generic_params(db);
+    let generic_params = db.generic_params(trait_.id.into());
     let bound_vars = Substs::bound_vars(&generic_params);
     let flags = chalk_rust_ir::TraitFlags {
         auto: trait_.is_auto(db),
@@ -594,7 +593,7 @@ pub(crate) fn struct_datum_query(
     let where_clauses = type_ctor
         .as_generic_def()
         .map(|generic_def| {
-            let generic_params = generic_def.generic_params(db);
+            let generic_params = db.generic_params(generic_def.into());
             let bound_vars = Substs::bound_vars(&generic_params);
             convert_where_clauses(db, generic_def, &bound_vars)
         })
@@ -634,7 +633,7 @@ fn impl_block_datum(
     impl_id: ImplId,
     impl_block: ImplBlock,
 ) -> Option<Arc<ImplDatum<ChalkIr>>> {
-    let generic_params = impl_block.generic_params(db);
+    let generic_params = db.generic_params(impl_block.id.into());
     let bound_vars = Substs::bound_vars(&generic_params);
     let trait_ref = impl_block.target_trait_ref(db)?.subst(&bound_vars);
     let trait_ = trait_ref.trait_;
@@ -786,7 +785,7 @@ fn type_alias_associated_ty_value(
     let assoc_ty = trait_
         .associated_type_by_name(db, &type_alias.name(db))
         .expect("assoc ty value should not exist"); // validated when building the impl data as well
-    let generic_params = impl_block.generic_params(db);
+    let generic_params = db.generic_params(impl_block.id.into());
     let bound_vars = Substs::bound_vars(&generic_params);
     let ty = db.type_for_def(type_alias.into(), crate::ty::Namespace::Types).subst(&bound_vars);
     let value_bound = chalk_rust_ir::AssociatedTyValueBound { ty: ty.to_chalk(db) };