Teach loadNamedMembers to import inherited constructors

Author: CodaFi

lib/AST/NameLookup.cpp

@@ -1274,13 +1274,6 @@ TinyPtrVector<ValueDecl *> NominalTypeDecl::lookupDirect(
   bool includeAttrImplements =
       flags.contains(LookupDirectFlags::IncludeAttrImplements);
 
-  // FIXME: At present, lazy member is not able to find inherited constructors
-  // in imported classes, because SwiftDeclConverter::importInheritedConstructors()
-  // is only called via ClangImporter::Implementation::loadAllMembers().
-  if (hasClangNode() &&
-      name.getBaseName() == DeclBaseName::createConstructor())
-    useNamedLazyMemberLoading = false;
-
   LLVM_DEBUG(llvm::dbgs() << getNameStr() << ".lookupDirect("
              << name << ")"
         << ", isLookupTablePopulated()=" << isLookupTablePopulated()

lib/ClangImporter/ClangImporter.cpp

@@ -3822,6 +3822,16 @@ ClangImporter::Implementation::loadNamedMembers(
       }
     }
   }
+
+  if (N == DeclBaseName::createConstructor()) {
+    if (auto *classDecl = dyn_cast<ClassDecl>(D)) {
+      SmallVector<Decl *, 4> ctors;
+      importInheritedConstructors(cast<clang::ObjCInterfaceDecl>(CD),
+                                  classDecl, ctors);
+      for (auto ctor : ctors)
+        Members.push_back(cast<ValueDecl>(ctor));
+    }
+  }
   return Members;
 }
 

lib/ClangImporter/ImportDecl.cpp

@@ -4518,8 +4518,7 @@ namespace {
     void importMirroredProtocolMembers(const clang::ObjCContainerDecl *decl,
                                        DeclContext *dc,
                                        ArrayRef<ProtocolDecl *> protocols,
-                                       SmallVectorImpl<Decl *> &members,
-                                       ASTContext &Ctx);
+                                       SmallVectorImpl<Decl *> &members);
 
     void importNonOverriddenMirroredMethods(DeclContext *dc,
                                   MutableArrayRef<MirroredMethodEntry> entries,
@@ -8672,6 +8671,15 @@ void ClangImporter::Implementation::insertMembersAndAlternates(
   });
 }
 
+void ClangImporter::Implementation::importInheritedConstructors(
+     const clang::ObjCInterfaceDecl *curObjCClass,
+     const ClassDecl *classDecl, SmallVectorImpl<Decl *> &newMembers) {
+   if (curObjCClass->getName() != "Protocol") {
+     SwiftDeclConverter converter(*this, CurrentVersion);
+     converter.importInheritedConstructors(classDecl, newMembers);
+   }
+ }
+
 void ClangImporter::Implementation::collectMembersToAdd(
     const clang::ObjCContainerDecl *objcContainer, Decl *D, DeclContext *DC,
     SmallVectorImpl<Decl *> &members) {
@@ -8686,15 +8694,8 @@ void ClangImporter::Implementation::collectMembersToAdd(
 
   auto protos = getImportedProtocols(D);
   if (auto clangClass = dyn_cast<clang::ObjCInterfaceDecl>(objcContainer)) {
-    auto swiftClass = cast<ClassDecl>(D);
     objcContainer = clangClass = clangClass->getDefinition();
-
-    // Imported inherited initializers.
-    if (clangClass->getName() != "Protocol") {
-      converter.importInheritedConstructors(const_cast<ClassDecl *>(swiftClass),
-                                            members);
-    }
-
+    importInheritedConstructors(clangClass, cast<ClassDecl>(D), members);
   } else if (auto clangProto
                = dyn_cast<clang::ObjCProtocolDecl>(objcContainer)) {
     objcContainer = clangProto->getDefinition();

lib/ClangImporter/ImporterImpl.h

@@ -812,6 +812,10 @@ class LLVM_LIBRARY_VISIBILITY ClangImporter::Implementation
   Decl *importMirroredDecl(const clang::NamedDecl *decl, DeclContext *dc,
                            Version version, ProtocolDecl *proto);
 
+  void importInheritedConstructors(const clang::ObjCInterfaceDecl *curObjCClass,
+                                   const ClassDecl *classDecl,
+                                   SmallVectorImpl<Decl *> &newMembers);
+  
   /// Utility function for building simple generic signatures.
   GenericSignature buildGenericSignature(GenericParamList *genericParams,
                                           DeclContext *dc);

test/ClangImporter/attr-swift_name.swift

@@ -1,5 +1,5 @@
 // RUN: %empty-directory(%t.mcp)
-// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -I %S/Inputs/custom-modules -Xcc -w -typecheck %s -module-cache-path %t.mcp 2>&1 | %FileCheck %s
+// RUN: %target-swift-frontend(mock-sdk: %clang-importer-sdk) -I %S/Inputs/custom-modules -Xcc -w -typecheck %s -module-cache-path %t.mcp -disable-named-lazy-member-loading 2>&1 | %FileCheck %s
 
 // REQUIRES: objc_interop
 

test/NameBinding/Inputs/NamedLazyMembers/NamedLazyMembers.h

@@ -26,6 +26,8 @@
 // Don't conform to the protocol; that loads all protocol members.
 @interface SimpleDoer
 
+- (instancetype)initWithValue: (int)value;
+
 // These are names we're hoping don't interfere with Doer, above.
 + (SimpleDoer*)Doer;
 + (SimpleDoer*)DoerOfNoWork;
@@ -107,4 +109,14 @@
 @interface SimpleDoerSubclass : SimpleDoer
 - (void)simplyDoSomeWorkWithSpeed:(int)s thoroughness:(int)t
   NS_SWIFT_NAME(simplyDoVeryImportantWork(speed:thoroughness:));
+
+- (void)exuberantlyGoForWalk;
+- (void)exuberantlyTakeNap;
+- (void)exuberantlyEatMeal;
+- (void)exuberantlyTidyHome;
+- (void)exuberantlyCallFamily;
+- (void)exuberantlySingSong;
+- (void)exuberantlyReadBook;
+- (void)exuberantlyAttendLecture;
+- (void)exuberantlyWriteLetter;
 @end

test/NameBinding/named_lazy_member_loading_objc_interface.swift

@@ -8,17 +8,23 @@
 // Check that named-lazy-member-loading reduces the number of Decls deserialized
 // RUN: %target-swift-frontend -typecheck -I %S/Inputs/NamedLazyMembers -disable-named-lazy-member-loading -stats-output-dir %t/stats-pre -primary-file %s %S/Inputs/NamedLazyMembers/NamedLazyMembersExt.swift
 // RUN: %target-swift-frontend -typecheck -I %S/Inputs/NamedLazyMembers -stats-output-dir %t/stats-post -primary-file %s %S/Inputs/NamedLazyMembers/NamedLazyMembersExt.swift
-// RUN: %{python} %utils/process-stats-dir.py --evaluate-delta 'NumTotalClangImportedEntities <= -1' %t/stats-pre %t/stats-post
+// RUN: %{python} %utils/process-stats-dir.py --evaluate-delta 'NumTotalClangImportedEntities <= -10' %t/stats-pre %t/stats-post
 
 import NamedLazyMembers
 
-public func bar(d: SimpleDoerSubclass) {
-    let _ = d.simplyDoVeryImportantWork(speed: 10, motivation: 42)
+public func bar() {
+  let d = SimpleDoerSubclass(value: 123)!
+  let _ = d.simplyDoVeryImportantWork(speed: 10, motivation: 42)
 }
 
-public func foo(d: SimpleDoer) {
+public func foo() {
+  let d = SimpleDoer(value: 123)!
   let _ = d.simplyDoSomeWork()
   let _ = d.simplyDoSomeWork(withSpeed:10)
   let _ = d.simplyDoVeryImportantWork(speed:10, thoroughness:12)
   let _ = d.simplyDoSomeWorkWithSpeed(speed:10, levelOfAlacrity:12)
 }
+
+// Make sure that simply subclassing an imported subclass doesn't page in all
+// members.
+class MostDoerSubclass : SimpleDoerSubclass {}