[AST] Add shouldHideFromEditor() method

This replaces shouldHideDeclFromCompletionResults() in IDE.

Author: rintaro

include/swift/AST/Decl.h

@@ -2412,6 +2412,10 @@ class ValueDecl : public Decl {
 
   bool isUsableFromInline() const;
 
+  /// Returns \c true if this declaration is *not* intended to be used directly
+  /// by application developers despite of the visibility.
+  bool shouldHideFromEditor() const;
+
   bool hasAccess() const {
     return TypeAndAccess.getInt().hasValue();
   }

lib/AST/Decl.cpp

@@ -2550,6 +2550,34 @@ bool ValueDecl::isUsableFromInline() const {
   return false;
 }
 
+/// Returns \c true if this declaration is *not* intended to be used directly
+/// by application developers despite of the visibility.
+bool ValueDecl::shouldHideFromEditor() const {
+  // Hide private stdlib declarations.
+  if (isPrivateStdlibDecl(/*treatNonBuiltinProtocolsAsPublic*/ false) ||
+      // ShowInInterfaceAttr is for decls to show in interface as exception but
+      // they are not intended to be used directly.
+      getAttrs().hasAttribute<ShowInInterfaceAttr>())
+    return true;
+
+  if (AvailableAttr::isUnavailable(this))
+    return true;
+
+  if (auto *ClangD = getClangDecl()) {
+    if (ClangD->hasAttr<clang::SwiftPrivateAttr>())
+      return true;
+  }
+
+  if (!isUserAccessible())
+    return true;
+
+  // Hide editor placeholders.
+  if (getBaseName().isEditorPlaceholder())
+    return true;
+
+  return false;
+}
+
 /// Return the access level of an internal or public declaration
 /// that's been testably imported.
 static AccessLevel getTestableOrPrivateImportsAccess(const ValueDecl *decl) {

lib/IDE/CodeCompletion.cpp

@@ -2116,7 +2116,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
   void addVarDeclRef(const VarDecl *VD, DeclVisibilityKind Reason) {
     if (!VD->hasName() ||
         !VD->isAccessibleFrom(CurrDeclContext) ||
-        shouldHideDeclFromCompletionResults(VD))
+        VD->shouldHideFromEditor())
       return;
 
     StringRef Name = VD->getName().get();
@@ -2637,7 +2637,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
                                          NL_QualifiedDefault,
                                          TypeResolver, initializers)) {
       for (auto *init : initializers) {
-        if (shouldHideDeclFromCompletionResults(init))
+        if (init->shouldHideFromEditor())
           continue;
         if (IsUnresolvedMember &&
             cast<ConstructorDecl>(init)->getFailability() == OTK_Optional) {
@@ -2782,7 +2782,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
                          bool HasTypeContext) {
     if (!EED->hasName() ||
         !EED->isAccessibleFrom(CurrDeclContext) ||
-        shouldHideDeclFromCompletionResults(EED))
+        EED->shouldHideFromEditor())
       return;
 
     CommandWordsPairs Pairs;
@@ -2895,7 +2895,7 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
 
   // Implement swift::VisibleDeclConsumer.
   void foundDecl(ValueDecl *D, DeclVisibilityKind Reason) override {
-    if (shouldHideDeclFromCompletionResults(D))
+    if (D->shouldHideFromEditor())
       return;
 
     if (IsKeyPathExpr && !KeyPathFilter(D, Reason))
@@ -4152,7 +4152,7 @@ class CompletionOverrideLookup : public swift::VisibleDeclConsumer {
     if (Reason == DeclVisibilityKind::MemberOfCurrentNominal)
       return;
 
-    if (shouldHideDeclFromCompletionResults(D))
+    if (D->shouldHideFromEditor())
       return;
 
     if (D->getAttrs().hasAttribute<FinalAttr>())
@@ -4993,7 +4993,7 @@ void collectPossibleCalleesByQualifiedLookup(
 
   for (auto *VD : decls) {
     if ((!isa<AbstractFunctionDecl>(VD) && !isa<SubscriptDecl>(VD)) ||
-        shouldHideDeclFromCompletionResults(VD))
+        VD->shouldHideFromEditor())
       continue;
     resolver->resolveDeclSignature(VD);
     if (!VD->hasInterfaceType())