add Clone auto impls

Author: basil-cow

chalk-solve/src/clauses/builtin_traits.rs

@@ -20,8 +20,10 @@ pub fn add_builtin_program_clauses<I: Interner>(
 
     match well_known {
         WellKnownTrait::SizedTrait => sized::add_sized_program_clauses(db, builder, trait_ref, ty),
-        WellKnownTrait::CopyTrait => copy::add_copy_program_clauses(db, builder, trait_ref, ty),
-        // Drop and Clone impls are provided explicitly
-        WellKnownTrait::CloneTrait | WellKnownTrait::DropTrait => (),
+        WellKnownTrait::CopyTrait | WellKnownTrait::CloneTrait => {
+            copy::add_copy_clone_program_clauses(db, builder, trait_ref, ty)
+        }
+        // Drop impls are provided explicitly
+        WellKnownTrait::DropTrait => (),
     }
 }

chalk-solve/src/clauses/builtin_traits/copy.rs

@@ -2,7 +2,8 @@ use crate::clauses::ClauseBuilder;
 use crate::{Interner, RustIrDatabase, TraitRef};
 use chalk_ir::TyData;
 
-pub fn add_copy_program_clauses<I: Interner>(
+/// Copy and Clone have the same automatic implementations
+pub fn add_copy_clone_program_clauses<I: Interner>(
     db: &dyn RustIrDatabase<I>,
     builder: &mut ClauseBuilder<'_, I>,
     trait_ref: &TraitRef<I>,