Chalk integration

- add proper canonicalization logic
 - add conversions from/to Chalk IR

crates/ra_hir/src/ids.rs

@@ -323,6 +323,25 @@ impl AstItemDef<ast::TraitDef> for TraitId {
     }
 }
 
+fn from_chalk<T: salsa::InternKey>(chalk_id: chalk_ir::RawId) -> T {
+    T::from_intern_id(salsa::InternId::from(chalk_id.index))
+}
+fn to_chalk<T: salsa::InternKey>(salsa_id: T) -> chalk_ir::RawId {
+    chalk_ir::RawId { index: salsa_id.as_intern_id().as_u32() }
+}
+
+impl From<chalk_ir::TraitId> for TraitId {
+    fn from(trait_id: chalk_ir::TraitId) -> Self {
+        from_chalk(trait_id.0)
+    }
+}
+
+impl From<TraitId> for chalk_ir::TraitId {
+    fn from(trait_id: TraitId) -> Self {
+        chalk_ir::TraitId(to_chalk(trait_id))
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct TypeAliasId(salsa::InternId);
 impl_intern_key!(TypeAliasId);
@@ -354,3 +373,38 @@ impl MacroCallId {
         )
     }
 }
+
+/// This exists just for chalk, because chalk doesn't differentiate between
+/// enums and structs.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct TypeCtorId(salsa::InternId);
+impl_intern_key!(TypeCtorId);
+
+impl From<chalk_ir::StructId> for TypeCtorId {
+    fn from(struct_id: chalk_ir::StructId) -> Self {
+        from_chalk(struct_id.0)
+    }
+}
+
+impl From<TypeCtorId> for chalk_ir::StructId {
+    fn from(adt_id: TypeCtorId) -> Self {
+        chalk_ir::StructId(to_chalk(adt_id))
+    }
+}
+
+/// This exists just for chalk, because our ImplIds are only unique per module.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct GlobalImplId(salsa::InternId);
+impl_intern_key!(GlobalImplId);
+
+impl From<chalk_ir::ImplId> for GlobalImplId {
+    fn from(impl_id: chalk_ir::ImplId) -> Self {
+        from_chalk(impl_id.0)
+    }
+}
+
+impl From<GlobalImplId> for chalk_ir::ImplId {
+    fn from(impl_id: GlobalImplId) -> Self {
+        chalk_ir::ImplId(to_chalk(impl_id))
+    }
+}