Merge pull request #19220 from apple/revert-19202-rework-type-checking-designated-protocol

Revert "Store ProtocolDecl rather than TypeLoc for designated protocol."

Author: benlangmuir

include/swift/AST/Decl.h

@@ -6272,7 +6272,7 @@ class OperatorDecl : public Decl {
 
   Identifier DesignatedProtocolName;
   SourceLoc DesignatedProtocolNameLoc;
-  ProtocolDecl *DesignatedProtocol;
+  TypeLoc DesignatedProtocolTypeLoc;
 
 public:
   OperatorDecl(DeclKind kind, DeclContext *DC, SourceLoc OperatorLoc,
@@ -6293,14 +6293,24 @@ class OperatorDecl : public Decl {
     return DesignatedProtocolName;
   }
 
+  void setDesignatedProtocolName(Identifier name) {
+    DesignatedProtocolName = name;
+  }
+
   SourceLoc getDesignatedProtocolNameLoc() const {
     return DesignatedProtocolNameLoc;
   }
 
-  ProtocolDecl *getDesignatedProtocol() const { return DesignatedProtocol; }
+  void setDesignatedProtocolNameLoc(SourceLoc loc) {
+    DesignatedProtocolNameLoc = loc;
+  }
+
+  TypeLoc getDesignatedProtocolTypeLoc() const {
+    return DesignatedProtocolTypeLoc;
+  }
 
-  void setDesignatedProtocol(ProtocolDecl *protocol) {
-    DesignatedProtocol = protocol;
+  void setDesignatedProtocolTypeLoc(TypeLoc typeLoc) {
+    DesignatedProtocolTypeLoc = typeLoc;
   }
 
   static bool classof(const Decl *D) {

lib/Sema/TypeCheckDecl.cpp

@@ -2074,14 +2074,14 @@ static void checkDesignatedProtocol(OperatorDecl *OD, Identifier name,
   }
 
   if (!typeLoc.isError()) {
+    OD->setDesignatedProtocolTypeLoc(typeLoc);
     auto *decl = typeLoc.getType()->getNominalOrBoundGenericNominal();
     if (!decl || !isa<ProtocolDecl>(decl)) {
       tc.diagnose(typeLoc.getLoc(),
                   diag::operators_designated_protocol_not_a_protocol,
                   typeLoc.getType());
       OD->setInvalid();
     } else {
-      OD->setDesignatedProtocol(cast<ProtocolDecl>(decl));
       // FIXME: verify this operator has a declaration within this
       //        protocol with the same arity and fixity
     }
@@ -2104,9 +2104,9 @@ void TypeChecker::validateDecl(OperatorDecl *OD) {
 
   // Pre- or post-fix operator?
   if (!IOD) {
-    auto *protocol = OD->getDesignatedProtocol();
+    auto typeLoc = OD->getDesignatedProtocolTypeLoc();
     auto protocolId = OD->getDesignatedProtocolName();
-    if (!protocol && !protocolId.empty() &&
+    if (typeLoc.isNull() && !protocolId.empty() &&
         enableOperatorDesignatedProtocols) {
       auto protocolIdLoc = OD->getDesignatedProtocolNameLoc();
       checkDesignatedProtocol(OD, protocolId, protocolIdLoc, *this, Context);
@@ -2127,8 +2127,8 @@ void TypeChecker::validateDecl(OperatorDecl *OD) {
     }
 
     auto secondId = IOD->getSecondIdentifier();
-    auto *protocol = IOD->getDesignatedProtocol();
-    if (!protocol && enableOperatorDesignatedProtocols) {
+    auto typeLoc = IOD->getDesignatedProtocolTypeLoc();
+    if (typeLoc.isNull() && enableOperatorDesignatedProtocols) {
       auto secondIdLoc = IOD->getSecondIdentifierLoc();
       assert(secondId.empty() || !firstId.empty());
 
@@ -2140,7 +2140,7 @@ void TypeChecker::validateDecl(OperatorDecl *OD) {
 
     if (!group && !IOD->isInvalid()) {
       if (!firstId.empty() &&
-          (!secondId.empty() || !IOD->getDesignatedProtocol())) {
+          (!secondId.empty() || IOD->getDesignatedProtocolTypeLoc().isNull())) {
         diagnose(firstIdLoc, diag::unknown_precedence_group, firstId);
         IOD->setInvalid();
       }