[clang][extract-api] Add Objective-C protocol support

Add support for Objective-C protocol declarations in ExtractAPI.

Depends on D122446

Differential Revision: https://reviews.llvm.org/D122511

4 files changed, 84 insertions, 0 deletions

diff --git a/clang/lib/ExtractAPI/API.cpp b/clang/lib/ExtractAPI/API.cpp
index 2456022..1c9314c 100644
--- a/clang/lib/ExtractAPI/API.cpp
+++ b/clang/lib/ExtractAPI/API.cpp
@@ -161,6 +161,20 @@ ObjCInstanceVariableRecord *APISet::addObjCInstanceVariable(
   return Container->Ivars.emplace_back(std::move(Record)).get();
 }
 
+ObjCProtocolRecord *APISet::addObjCProtocol(
+    StringRef Name, StringRef USR, PresumedLoc Loc,
+    const AvailabilityInfo &Availability, const DocComment &Comment,
+    DeclarationFragments Declaration, DeclarationFragments SubHeading) {
+  auto Result = ObjCProtocols.insert({Name, nullptr});
+  if (Result.second) {
+    // Create the record if it does not already exist.
+    auto Record = std::make_unique<ObjCProtocolRecord>(
+        Name, USR, Loc, Availability, Comment, Declaration, SubHeading);
+    Result.first->second = std::move(Record);
+  }
+  return Result.first->second.get();
+}
+
 StringRef APISet::recordUSR(const Decl *D) {
   SmallString<128> USR;
   index::generateUSRForDecl(D, USR);
@@ -193,3 +207,4 @@ void ObjCPropertyRecord::anchor() {}
 void ObjCInstanceVariableRecord::anchor() {}
 void ObjCMethodRecord::anchor() {}
 void ObjCInterfaceRecord::anchor() {}
+void ObjCProtocolRecord::anchor() {}
diff --git a/clang/lib/ExtractAPI/DeclarationFragments.cpp b/clang/lib/ExtractAPI/DeclarationFragments.cpp
index b35388e..7c6c9dc 100644
--- a/clang/lib/ExtractAPI/DeclarationFragments.cpp
+++ b/clang/lib/ExtractAPI/DeclarationFragments.cpp
@@ -621,6 +621,35 @@ DeclarationFragments DeclarationFragmentsBuilder::getFragmentsForObjCProperty(
       .append(std::move(After));
 }
 
+DeclarationFragments DeclarationFragmentsBuilder::getFragmentsForObjCProtocol(
+    const ObjCProtocolDecl *Protocol) {
+  DeclarationFragments Fragments;
+  // Build basic protocol declaration.
+  Fragments.append("@protocol", DeclarationFragments::FragmentKind::Keyword)
+      .appendSpace()
+      .append(Protocol->getName(),
+              DeclarationFragments::FragmentKind::Identifier);
+
+  // If this protocol conforms to other protocols, build the conformance list.
+  if (!Protocol->protocols().empty()) {
+    Fragments.append(" <", DeclarationFragments::FragmentKind::Text);
+    for (ObjCProtocolDecl::protocol_iterator It = Protocol->protocol_begin();
+         It != Protocol->protocol_end(); It++) {
+      // Add a leading comma if this is not the first protocol rendered.
+      if (It != Protocol->protocol_begin())
+        Fragments.append(", ", DeclarationFragments::FragmentKind::Text);
+
+      SmallString<128> USR;
+      index::generateUSRForDecl(*It, USR);
+      Fragments.append((*It)->getName(),
+                       DeclarationFragments::FragmentKind::TypeIdentifier, USR);
+    }
+    Fragments.append(">", DeclarationFragments::FragmentKind::Text);
+  }
+
+  return Fragments;
+}
+
 template <typename FunctionT>
 FunctionSignature
 DeclarationFragmentsBuilder::getFunctionSignature(const FunctionT *Function) {
diff --git a/clang/lib/ExtractAPI/ExtractAPIConsumer.cpp b/clang/lib/ExtractAPI/ExtractAPIConsumer.cpp
index f8b1c9b..bcc01db 100644
--- a/clang/lib/ExtractAPI/ExtractAPIConsumer.cpp
+++ b/clang/lib/ExtractAPI/ExtractAPIConsumer.cpp
@@ -260,6 +260,38 @@ public:
     return true;
   }
 
+  bool VisitObjCProtocolDecl(const ObjCProtocolDecl *Decl) {
+    // Skip forward declaration for protocols (@protocol).
+    if (!Decl->isThisDeclarationADefinition())
+      return true;
+
+    // Collect symbol information.
+    StringRef Name = Decl->getName();
+    StringRef USR = API.recordUSR(Decl);
+    PresumedLoc Loc =
+        Context.getSourceManager().getPresumedLoc(Decl->getLocation());
+    AvailabilityInfo Availability = getAvailability(Decl);
+    DocComment Comment;
+    if (auto *RawComment = Context.getRawCommentForDeclNoCache(Decl))
+      Comment = RawComment->getFormattedLines(Context.getSourceManager(),
+                                              Context.getDiagnostics());
+
+    // Build declaration fragments and sub-heading for the protocol.
+    DeclarationFragments Declaration =
+        DeclarationFragmentsBuilder::getFragmentsForObjCProtocol(Decl);
+    DeclarationFragments SubHeading =
+        DeclarationFragmentsBuilder::getSubHeading(Decl);
+
+    ObjCProtocolRecord *ObjCProtocolRecord = API.addObjCProtocol(
+        Name, USR, Loc, Availability, Comment, Declaration, SubHeading);
+
+    recordObjCMethods(ObjCProtocolRecord, Decl->methods());
+    recordObjCProperties(ObjCProtocolRecord, Decl->properties());
+    recordObjCProtocols(ObjCProtocolRecord, Decl->protocols());
+
+    return true;
+  }
+
 private:
   /// Get availability information of the declaration \p D.
   AvailabilityInfo getAvailability(const Decl *D) const {
diff --git a/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp b/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp
index 3faf9cd..1acb67a 100644
--- a/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp
+++ b/clang/lib/ExtractAPI/Serialization/SymbolGraphSerializer.cpp
@@ -393,6 +393,10 @@ Object serializeSymbolKind(const APIRecord &Record, Language Lang) {
     Kind["identifier"] = AddLangPrefix("class");
     Kind["displayName"] = "Class";
     break;
+  case APIRecord::RK_ObjCProtocol:
+    Kind["identifier"] = AddLangPrefix("protocol");
+    Kind["displayName"] = "Protocol";
+    break;
   }
 
   return Kind;
@@ -593,6 +597,10 @@ Object SymbolGraphSerializer::serialize() {
   for (const auto &ObjCInterface : API.getObjCInterfaces())
     serializeObjCContainerRecord(*ObjCInterface.second);
 
+  // Serialize Objective-C protocol records in the API set.
+  for (const auto &ObjCProtocol : API.getObjCProtocols())
+    serializeObjCContainerRecord(*ObjCProtocol.second);
+
   Root["symbols"] = std::move(Symbols);
   Root["relationhips"] = std::move(Relationships);