From 27445a06a78b13e344d21d11ee21851465dc4d55 Mon Sep 17 00:00:00 2001
From: Wilco Kusee <wilcokusee@gmail.com>
Date: Thu, 16 Apr 2020 20:07:54 +0200
Subject: [PATCH] Show name in opaque type debug output

---
 chalk-integration/src/lowering.rs | 1 +
 chalk-integration/src/program.rs  | 9 ++++++---
 chalk-ir/src/debug.rs             | 2 +-
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/chalk-integration/src/lowering.rs b/chalk-integration/src/lowering.rs
index 02e4d782a3b..9fb842109a4 100644
--- a/chalk-integration/src/lowering.rs
+++ b/chalk-integration/src/lowering.rs
@@ -446,6 +446,7 @@ impl LowerProgram for Program {
             associated_ty_values,
             associated_ty_data,
             opaque_ty_ids,
+            opaque_ty_kinds,
             opaque_ty_data,
             custom_clauses,
         };
diff --git a/chalk-integration/src/program.rs b/chalk-integration/src/program.rs
index 55d62709acd..86389985b74 100644
--- a/chalk-integration/src/program.rs
+++ b/chalk-integration/src/program.rs
@@ -45,6 +45,9 @@ pub struct Program {
     // From opaque type name to item-id. Used during lowering only.
     pub opaque_ty_ids: BTreeMap<Identifier, OpaqueTyId<ChalkIr>>,
 
+    /// For each opaque type:
+    pub opaque_ty_kinds: BTreeMap<OpaqueTyId<ChalkIr>, TypeKind>,
+
     /// For each opaque type:
     pub opaque_ty_data: BTreeMap<OpaqueTyId<ChalkIr>, Arc<OpaqueTyDatum<ChalkIr>>>,
 
@@ -120,8 +123,8 @@ impl tls::DebugContext for Program {
         opaque_ty_id: OpaqueTyId<ChalkIr>,
         fmt: &mut fmt::Formatter<'_>,
     ) -> Result<(), fmt::Error> {
-        if let Some(d) = self.opaque_ty_data.get(&opaque_ty_id) {
-            write!(fmt, "{:?}", d.bound.skip_binders().hidden_ty)
+        if let Some(k) = self.opaque_ty_kinds.get(&opaque_ty_id) {
+            write!(fmt, "{}", k.name)
         } else {
             fmt.debug_struct("InvalidItemId")
                 .field("index", &opaque_ty_id.0)
@@ -162,7 +165,7 @@ impl tls::DebugContext for Program {
         opaque_ty: &OpaqueTy<ChalkIr>,
         fmt: &mut fmt::Formatter<'_>,
     ) -> Result<(), fmt::Error> {
-        write!(fmt, "impl {:?}", opaque_ty.opaque_ty_id)
+        write!(fmt, "{:?}", opaque_ty.opaque_ty_id)
     }
 
     fn debug_ty(&self, ty: &Ty<ChalkIr>, fmt: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
diff --git a/chalk-ir/src/debug.rs b/chalk-ir/src/debug.rs
index bcb6c7630b7..69dc38b10e1 100644
--- a/chalk-ir/src/debug.rs
+++ b/chalk-ir/src/debug.rs
@@ -141,7 +141,7 @@ impl<I: Interner> Debug for TypeName<I> {
         match self {
             TypeName::Struct(id) => write!(fmt, "{:?}", id),
             TypeName::AssociatedType(assoc_ty) => write!(fmt, "{:?}", assoc_ty),
-            TypeName::OpaqueType(opaque_ty) => write!(fmt, "{:?}", opaque_ty),
+            TypeName::OpaqueType(opaque_ty) => write!(fmt, "!{:?}", opaque_ty),
             TypeName::Error => write!(fmt, "{{error}}"),
         }
     }