[SymbolGraph] don't emit symbols for implicit inherited initializers (#41985)

rdar://90401347

Author: QuietMisdreavus

lib/SymbolGraphGen/SymbolGraph.cpp

@@ -679,8 +679,12 @@ bool SymbolGraph::canIncludeDeclAsNode(const Decl *D) const {
   if (D->getModuleContext()->getName() != M.getName() && !Walker.isFromExportedImportedModule(D)) {
     return false;
   }
-  
-  if (!isa<ValueDecl>(D)) {
+
+  if (const auto *VD = dyn_cast<ValueDecl>(D)) {
+    if (VD->getOverriddenDecl() && D->isImplicit()) {
+      return false;
+    }
+  } else {
     return false;
   }
   return !isImplicitlyPrivate(cast<ValueDecl>(D)) 

test/SymbolGraph/ClangImporter/ObjcProperty.swift

@@ -3,11 +3,25 @@
 // RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -enable-objc-interop -emit-module -o %t/ObjcProperty.framework/Modules/ObjcProperty.swiftmodule/%target-swiftmodule-name -import-underlying-module -F %t -module-name ObjcProperty -disable-objc-attr-requires-foundation-module %s
 // RUN: %target-swift-symbolgraph-extract -sdk %clang-importer-sdk -module-name ObjcProperty -F %t -output-dir %t -pretty-print -v
 // RUN: %FileCheck %s --input-file %t/ObjcProperty.symbols.json
+// RUN: %FileCheck %s --input-file %t/ObjcProperty.symbols.json --check-prefix XLANG
 
 // REQUIRES: objc_interop
 
 import Foundation
 
 public enum SwiftEnum {}
 
+public class SwiftClass : Foo {}
+
+// ensure that synthesized inherited objc symbols do not appear in the symbol graph
+
+// CHECK-NOT:       "c:objc(cs)NSObject(im)init"
+
+// ensure that children of clang nodes appear in the symbol graph
+
 // CHECK: "precise": "c:objc(cs)Foo(py)today"
+
+// ensure that a swift class that inherits from an objc class still doesn't generate inherited
+// symbols
+
+// XLANG-COUNT-2: selectDate:

test/SymbolGraph/Relationships/Synthesized/SuperclassImplementation.swift

@@ -19,8 +19,14 @@ public class Base {
 
 public class Derived: Base {
   // CHECK-NOT: "precise": "s:24SuperclassImplementation4BaseC3fooyyF::SYNTHESIZED::s:24SuperclassImplementation7DerivedC"
+
+  // Also skip synthesized constructors
+  // CHECK-NOT: "precise": "s:24SuperclassImplementation7DerivedCACycfc"
 }
 
 public class DerivedDerived: Derived {
   // CHECK-NOT: "precise": "s:24SuperclassImplementation4BaseC3fooyyF::SYNTHESIZED::s:24SuperclassImplementation07DerivedC0C"
+
+  // Also skip synthesized constructors
+  // CHECK-NOT: "precise": "s:24SuperclassImplementation07DerivedC0CACycfc"
 }