Merge pull request #13644 from davezarzycki/nfc_hasParenSema

Author: swift-ci

include/swift/AST/Types.h

@@ -1633,6 +1633,16 @@ class TupleType final : public TypeBase, public llvm::FoldingSetNode,
     return static_cast<bool>(Bits.TupleType.HasInOutElement);
   }
 
+  /// Returns true if this tuple has parenthesis semantics.
+  bool hasParenSema(bool allowName = false) const {
+    auto Fields = getElements();
+    if (Fields.size() != 1 || Fields[0].isVararg())
+     return false;
+    if (allowName)
+      return true;
+    return !Fields[0].hasName();
+  }
+
   // Implement isa/cast/dyncast/etc.
   static bool classof(const TypeBase *T) {
     return T->getKind() == TypeKind::Tuple;

lib/AST/Type.cpp

@@ -685,7 +685,7 @@ Type TypeBase::getWithoutParens() {
 Type TypeBase::getWithoutImmediateLabel() {
   Type Ty = this;
   if (auto tupleTy = dyn_cast<TupleType>(Ty.getPointer())) {
-    if (tupleTy->getNumElements() == 1 && !tupleTy->getElement(0).isVararg())
+    if (tupleTy->hasParenSema(/*allowName*/true))
       Ty = tupleTy->getElementType(0);
   }
   return Ty;
@@ -870,7 +870,7 @@ Type TypeBase::getRValueInstanceType() {
 
   // Look through argument list tuples.
   if (auto tupleTy = type->getAs<TupleType>()) {
-    if (tupleTy->getNumElements() == 1 && !tupleTy->getElement(0).isVararg())
+    if (tupleTy->hasParenSema(/*allowName*/true))
       type = tupleTy->getElementType(0);
   }
 

lib/Sema/CSSimplify.cpp

@@ -1965,8 +1965,7 @@ ConstraintSystem::matchTypes(Type type1, Type type2, ConstraintKind kind,
       // For non-argument tuples, we can do the same conversion but not
       // to a tuple with varargs.
       if (!type1->is<LValueType>() &&
-          ((tuple2->getNumElements() == 1 &&
-            !tuple2->getElement(0).isVararg()) ||
+          (tuple2->hasParenSema(/*allowName*/true) ||
            (kind >= ConstraintKind::Conversion &&
             tuple2->getElementForScalarInit() >= 0 &&
             (isArgumentTupleConversion ||

lib/Sema/TypeCheckPattern.cpp

@@ -973,8 +973,7 @@ bool TypeChecker::coercePatternToType(Pattern *&P, DeclContext *dc, Type type,
     if ((options & TypeResolutionFlags::EnumPatternPayload)
         && !isa<TuplePattern>(semantic)) {
       if (auto tupleType = type->getAs<TupleType>()) {
-        if (tupleType->getNumElements() == 1
-            && !tupleType->getElement(0).isVararg()) {
+        if (tupleType->hasParenSema(/*allowName*/true)) {
           auto elementTy = tupleType->getElementType(0);
           if (coercePatternToType(sub, dc, elementTy, subOptions, resolver))
             return true;