Merge pull request #26138 from slavapestov/remove-get-witness-type

Remove TypeChecker::getWitnessType()

Author: slavapestov

lib/Sema/TypeCheckProtocol.cpp

@@ -5473,15 +5473,3 @@ void TypeChecker::inferDefaultWitnesses(ProtocolDecl *proto) {
         req.getFirstType()->getCanonicalType(), requirementProto, *conformance);
   }
 }
-
-Type TypeChecker::getWitnessType(Type type, ProtocolDecl *protocol,
-                                 ProtocolConformanceRef conformance,
-                                 Identifier name,
-                                 Diag<> brokenProtocolDiag) {
-  Type ty = conformance.getTypeWitnessByName(type, name);
-  if (!ty &&
-      !(conformance.isConcrete() && conformance.getConcrete()->isInvalid()))
-    diagnose(protocol->getLoc(), brokenProtocolDiag);
-
-  return (!ty || ty->hasError()) ? Type() : ty;
-}

lib/Sema/TypeCheckStmt.cpp

@@ -763,9 +763,8 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
         return nullptr;
       S->setSequenceConformance(conformance);
 
-      iteratorTy = TC.getWitnessType(sequenceType, sequenceProto, *conformance,
-                                     TC.Context.Id_Iterator,
-                                     diag::sequence_protocol_broken);
+      iteratorTy = conformance->getTypeWitnessByName(sequenceType,
+                                                     TC.Context.Id_Iterator);
       if (!iteratorTy)
         return nullptr;
 
@@ -796,7 +795,7 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
       // be around.
       auto nextResultType =
           OptionalType::get(conformance->getTypeWitnessByName(
-                                sequenceType, DC->getASTContext().Id_Element))
+                                sequenceType, TC.Context.Id_Element))
               ->getCanonicalType();
       auto *genBinding = PatternBindingDecl::createImplicit(
           TC.Context, StaticSpellingKind::None, genPat,
@@ -829,9 +828,8 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
     if (!genConformance)
       return nullptr;
 
-    Type elementTy = TC.getWitnessType(iteratorTy, iteratorProto,
-                                       *genConformance, TC.Context.Id_Element,
-                                       diag::iterator_protocol_broken);
+    Type elementTy = genConformance->getTypeWitnessByName(iteratorTy,
+                                                        TC.Context.Id_Element);
     if (!elementTy)
       return nullptr;
 

lib/Sema/TypeChecker.h

@@ -1536,26 +1536,6 @@ class TypeChecker final : public LazyResolver {
   /// array literals exist.
   bool requireArrayLiteralIntrinsics(SourceLoc loc);
 
-  /// Retrieve the witness type with the given name.
-  ///
-  /// \param type The type that conforms to the given protocol.
-  ///
-  /// \param protocol The protocol through which we're looking.
-  ///
-  /// \param conformance The protocol conformance.
-  ///
-  /// \param name The name of the associated type.
-  ///
-  /// \param brokenProtocolDiag Diagnostic to emit if the type cannot be
-  /// accessed.
-  ///
-  /// \return the witness type, or null if an error occurs or the type
-  /// returned would contain an ErrorType.
-  Type getWitnessType(Type type, ProtocolDecl *protocol,
-                      ProtocolConformanceRef conformance,
-                      Identifier name,
-                      Diag<> brokenProtocolDiag);
-
   /// Build a call to the witness with the given name and arguments.
   ///
   /// \param base The base expression, whose witness will be invoked.