[Expr/AST] Add unresolvedApply component to handle method arguments.

include/swift/AST/Expr.h

@@ -5889,6 +5889,7 @@ public:
   public:
     enum class Kind : unsigned {
       Invalid,
+      UnresolvedApply,
       UnresolvedMember,
       UnresolvedSubscript,
       Member,
@@ -5914,13 +5915,15 @@ public:
 
     ArgumentList *ArgList;
     const ProtocolConformanceRef *HashableConformancesData;
+    std::optional<FunctionRefInfo> ComponentFuncRefKind;
 
     unsigned TupleIndex;
     Kind KindValue;
     Type ComponentType;
     SourceLoc Loc;
 
-    // Private constructor for subscript component.
+    // Private constructor for unresolvedSubscript, subscript and
+    // unresolvedApply component.
     explicit Component(DeclNameOrRef decl, ArgumentList *argList,
                        ArrayRef<ProtocolConformanceRef> indexHashables,
                        Kind kind, Type type, SourceLoc loc);
@@ -5933,6 +5936,14 @@ public:
       Decl = decl;
     }
 
+    // Private constructor for an unresolvedMember or member kind.
+    explicit Component(DeclNameOrRef decl, Kind kind, Type type,
+                       FunctionRefInfo funcRefKind, SourceLoc loc)
+        : Decl(decl), ComponentFuncRefKind(funcRefKind), KindValue(kind),
+          ComponentType(type), Loc(loc) {
+      assert(kind == Kind::Member || kind == Kind::UnresolvedMember);
+    }
+
     // Private constructor for tuple element kind.
     explicit Component(unsigned tupleIndex, Type elementType, SourceLoc loc)
         : Component(Kind::TupleElement, elementType, loc) {
@@ -5941,15 +5952,25 @@ public:
 
     // Private constructor for basic components with no additional information.
     explicit Component(Kind kind, Type type, SourceLoc loc)
-        : Decl(), KindValue(kind), ComponentType(type), Loc(loc) {}
+        : Decl(), ComponentFuncRefKind(std::nullopt), KindValue(kind),
+          ComponentType(type), Loc(loc) {}
 
   public:
     Component() : Component(Kind::Invalid, Type(), SourceLoc()) {}
 
-    /// Create an unresolved component for a member.
+    /// Create an unresolved component for an unresolved apply.
+    static Component forUnresolvedApply(ASTContext &ctx,
+                                        ArgumentList *argList) {
+      return Component({}, argList, {}, Kind::UnresolvedApply, Type(),
+                       argList->getLParenLoc());
+    };
+
+    /// Create an unresolved component for an unresolved member.
     static Component forUnresolvedMember(DeclNameRef UnresolvedName,
-                                         SourceLoc Loc) {
-      return Component(UnresolvedName, Kind::UnresolvedMember, Type(), Loc);
+                                         FunctionRefInfo funcRefKind,
+                                         SourceLoc loc) {
+      return Component(UnresolvedName, Kind::UnresolvedMember, Type(),
+                       funcRefKind, loc);
     }
 
     /// Create an unresolved component for a subscript.
@@ -5967,9 +5988,8 @@ public:
     }
     
     /// Create a component for a property.
-    static Component forProperty(ConcreteDeclRef property,
-                                 Type propertyType,
-                                 SourceLoc loc) {
+    static Component forMember(ConcreteDeclRef property, Type propertyType,
+                               SourceLoc loc) {
       return Component(property, Kind::Member, propertyType, loc);
     }
 
@@ -6054,6 +6074,7 @@ public:
 
       case Kind::UnresolvedSubscript:
       case Kind::UnresolvedMember:
+      case Kind::UnresolvedApply:
       case Kind::Invalid:
       case Kind::CodeCompletion:
         return false;
@@ -6065,6 +6086,7 @@ public:
       switch (getKind()) {
       case Kind::Subscript:
       case Kind::UnresolvedSubscript:
+      case Kind::UnresolvedApply:
         return ArgList;
 
       case Kind::Invalid:
@@ -6099,6 +6121,7 @@ public:
       case Kind::OptionalChain:
       case Kind::OptionalWrap:
       case Kind::OptionalForce:
+      case Kind::UnresolvedApply:
       case Kind::UnresolvedMember:
       case Kind::Member:
       case Kind::Identity:
@@ -6122,6 +6145,7 @@ public:
       case Kind::OptionalChain:
       case Kind::OptionalWrap:
       case Kind::OptionalForce:
+      case Kind::UnresolvedApply:
       case Kind::Member:
       case Kind::Identity:
       case Kind::TupleElement:
@@ -6140,6 +6164,7 @@ public:
       case Kind::Invalid:
       case Kind::UnresolvedMember:
       case Kind::UnresolvedSubscript:
+      case Kind::UnresolvedApply:
       case Kind::OptionalChain:
       case Kind::OptionalWrap:
       case Kind::OptionalForce:
@@ -6161,6 +6186,7 @@ public:
       case Kind::Invalid:
       case Kind::UnresolvedMember:
       case Kind::UnresolvedSubscript:
+      case Kind::UnresolvedApply:
       case Kind::OptionalChain:
       case Kind::OptionalWrap:
       case Kind::OptionalForce:
@@ -6181,6 +6207,7 @@ public:
         case Kind::Invalid:
         case Kind::UnresolvedMember:
         case Kind::UnresolvedSubscript:
+        case Kind::UnresolvedApply:
         case Kind::OptionalChain:
         case Kind::OptionalWrap:
         case Kind::OptionalForce:
@@ -6194,6 +6221,30 @@ public:
       llvm_unreachable("unhandled kind");
     }
 
+    FunctionRefInfo getFunctionRefInfo() const {
+      switch (getKind()) {
+      case Kind::UnresolvedMember:
+        assert(ComponentFuncRefKind &&
+               "FunctionRefInfo should not be nullopt for UnresolvedMember");
+        return *ComponentFuncRefKind;
+
+      case Kind::Member:
+      case Kind::Subscript:
+      case Kind::Invalid:
+      case Kind::UnresolvedSubscript:
+      case Kind::OptionalChain:
+      case Kind::OptionalWrap:
+      case Kind::OptionalForce:
+      case Kind::Identity:
+      case Kind::TupleElement:
+      case Kind::DictionaryKey:
+      case Kind::CodeCompletion:
+      case Kind::UnresolvedApply:
+        llvm_unreachable("no function ref kind for this kind");
+      }
+      llvm_unreachable("unhandled kind");
+    }
+
     Type getComponentType() const {
       return ComponentType;
     }