[NFC] Fixup TypeChecker::getOptionalType To Not Return Type()

Author: CodaFi

lib/Sema/CSGen.cpp

@@ -2404,6 +2404,7 @@ namespace {
           }
 
           varType = TypeChecker::getOptionalType(var->getLoc(), varType);
+          assert(!varType->hasError());
 
           if (oneWayVarType) {
             oneWayVarType =
@@ -3304,7 +3305,7 @@ namespace {
     /// worth QoI efforts.
     Type getOptionalType(SourceLoc optLoc, Type valueTy) {
       auto optTy = TypeChecker::getOptionalType(optLoc, valueTy);
-      if (!optTy ||
+      if (optTy->hasError() ||
           TypeChecker::requireOptionalIntrinsics(CS.getASTContext(), optLoc))
         return Type();
 

lib/Sema/CSSimplify.cpp

@@ -6889,6 +6889,7 @@ ConstraintSystem::SolutionKind ConstraintSystem::simplifyMemberConstraint(
                                         TVO_CanBindToLValue |
                                         TVO_CanBindToNoEscape);
       Type optTy = TypeChecker::getOptionalType(SourceLoc(), innerTV);
+      assert(!optTy->hasError());
       SmallVector<Constraint *, 2> optionalities;
       auto nonoptionalResult = Constraint::createFixed(
           *this, ConstraintKind::Bind,

lib/Sema/TypeCheckType.cpp

@@ -374,7 +374,7 @@ Type TypeChecker::getOptionalType(SourceLoc loc, Type elementType) {
   ASTContext &ctx = elementType->getASTContext();
   if (!ctx.getOptionalDecl()) {
     ctx.Diags.diagnose(loc, diag::sugar_type_not_found, 1);
-    return Type();
+    return ErrorType::get(ctx);
   }
 
   return OptionalType::get(elementType);
@@ -3342,14 +3342,16 @@ Type TypeResolver::resolveOptionalType(OptionalTypeRepr *repr,
   TypeResolutionOptions elementOptions = options.withoutContext(true);
   elementOptions.setContext(TypeResolverContext::ImmediateOptionalTypeArgument);
 
-  // The T in T? is a generic type argument and therefore always an AST type.
-  // FIXME: diagnose non-materializability of element type!
   Type baseTy = resolveType(repr->getBase(), elementOptions);
-  if (!baseTy || baseTy->hasError()) return baseTy;
+  if (!baseTy || baseTy->hasError()) {
+    return ErrorType::get(Context);
+  }
 
   auto optionalTy = TypeChecker::getOptionalType(repr->getQuestionLoc(),
                                                  baseTy);
-  if (!optionalTy) return ErrorType::get(Context);
+  if (optionalTy->hasError()) {
+    return ErrorType::get(Context);
+  }
 
   return optionalTy;
 }
@@ -3412,17 +3414,16 @@ Type TypeResolver::resolveImplicitlyUnwrappedOptionalType(
   TypeResolutionOptions elementOptions = options.withoutContext(true);
   elementOptions.setContext(TypeResolverContext::ImmediateOptionalTypeArgument);
 
-  // The T in T! is a generic type argument and therefore always an AST type.
-  // FIXME: diagnose non-materializability of element type!
   Type baseTy = resolveType(repr->getBase(), elementOptions);
-  if (!baseTy || baseTy->hasError()) return baseTy;
-
-  Type uncheckedOptionalTy;
-  uncheckedOptionalTy = TypeChecker::getOptionalType(repr->getExclamationLoc(),
-                                                     baseTy);
+  if (!baseTy || baseTy->hasError()) {
+    return ErrorType::get(Context);
+  }
 
-  if (!uncheckedOptionalTy)
+  Type uncheckedOptionalTy =
+      TypeChecker::getOptionalType(repr->getExclamationLoc(), baseTy);
+  if (uncheckedOptionalTy->hasError()) {
     return ErrorType::get(Context);
+  }
 
   return uncheckedOptionalTy;
 }