Remove DeclContext::isCascadingContextForLookup

Author: CodaFi

include/swift/AST/DeclContext.h

@@ -508,14 +508,6 @@ class alignas(1 << DeclContextAlignInBits) DeclContext {
   /// FIXME: do this for Protocols, too someday
   bool canBeParentOfExtension() const;
 
-  /// Returns true if lookups within this context could affect downstream files.
-  ///
-  /// \param functionsAreNonCascading If true, functions are considered non-
-  /// cascading contexts. If false, functions are considered non-cascading only
-  /// if implicitly or explicitly marked private. When concerned only with a
-  /// function's body, pass true.
-  bool isCascadingContextForLookup(bool functionsAreNonCascading) const;
-
   /// Look for the set of declarations with the given name within a type,
   /// its extensions and, optionally, its supertypes.
   ///

lib/AST/ASTScopeLookup.cpp

@@ -525,13 +525,9 @@ NullablePtr<const ASTScopeImpl> ASTScopeImpl::ancestorWithDeclSatisfying(
 
 #pragma mark ifUnknownIsCascadingUseAccordingTo
 
-static bool isCascadingUseAccordingTo(const DeclContext *const dc) {
-  return dc->isCascadingContextForLookup(false);
-}
-
 static bool ifUnknownIsCascadingUseAccordingTo(Optional<bool> isCascadingUse,
                                                const DeclContext *const dc) {
-  return isCascadingUse.getValueOr(isCascadingUseAccordingTo(dc));
+  return isCascadingUse.getValueOr(false);
 }
 
 #pragma mark resolveIsCascadingUseForThisScope
@@ -550,8 +546,7 @@ Optional<bool> GenericParamScope::resolveIsCascadingUseForThisScope(
 
 Optional<bool> AbstractFunctionDeclScope::resolveIsCascadingUseForThisScope(
     Optional<bool> isCascadingUse) const {
-  return decl->isCascadingContextForLookup(false) &&
-         isCascadingUse.getValueOr(true);
+  return false;
 }
 
 Optional<bool> AbstractFunctionBodyScope::resolveIsCascadingUseForThisScope(

lib/AST/DeclContext.cpp

@@ -445,52 +445,6 @@ bool DeclContext::isInnermostContextGeneric() const {
   return false;
 }
 
-bool
-DeclContext::isCascadingContextForLookup(bool functionsAreNonCascading) const {
-  // FIXME: This is explicitly checking for attributes in some cases because
-  // it can be called before access control is computed.
-  switch (getContextKind()) {
-  case DeclContextKind::AbstractClosureExpr:
-    break;
-
-  case DeclContextKind::SerializedLocal:
-    llvm_unreachable("should not perform lookups in deserialized contexts");
-
-  case DeclContextKind::Initializer:
-    // Default arguments still require a type.
-    if (isa<DefaultArgumentInitializer>(this))
-      return false;
-    break;
-
-  case DeclContextKind::TopLevelCodeDecl:
-    // FIXME: Pattern initializers at top-level scope end up here.
-    return true;
-
-  case DeclContextKind::AbstractFunctionDecl:
-    if (functionsAreNonCascading)
-      return false;
-    break;
-
-  case DeclContextKind::SubscriptDecl:
-    break;
-
-  case DeclContextKind::EnumElementDecl:
-    break;
-
-  case DeclContextKind::Module:
-  case DeclContextKind::FileUnit:
-    return true;
-
-  case DeclContextKind::GenericTypeDecl:
-    break;
-
-  case DeclContextKind::ExtensionDecl:
-    return true;
-  }
-
-  return getParent()->isCascadingContextForLookup(true);
-}
-
 unsigned DeclContext::getSyntacticDepth() const {
   // Module scope == depth 0.
   if (isModuleScopeContext())

lib/AST/NameLookupRequests.cpp

@@ -371,18 +371,7 @@ swift::extractNearestSourceLoc(const LookupConformanceDescriptor &desc) {
 evaluator::DependencySource ModuleQualifiedLookupRequest::readDependencySource(
     const evaluator::DependencyRecorder &eval) const {
   auto *DC = std::get<0>(getStorage());
-  auto options = std::get<3>(getStorage());
-
-  // FIXME(Evaluator Incremental Dependencies): This is an artifact of the
-  // current scheme and should be removed. There are very few callers that are
-  // accurately passing the right known dependencies mask.
-  const bool fromPrivateDC =
-      DC->isCascadingContextForLookup(/*functionsAreNonCascading=*/false);
-
-  auto scope = evaluator::DependencyScope::Cascading;
-  if (fromPrivateDC)
-    scope = evaluator::DependencyScope::Private;
-  return { DC->getParentSourceFile(), scope };
+  return { DC->getParentSourceFile(), evaluator::DependencyScope::Private };
 }
 
 void ModuleQualifiedLookupRequest::writeDependencySink(
@@ -453,18 +442,9 @@ void UnqualifiedLookupRequest::writeDependencySink(
 evaluator::DependencySource QualifiedLookupRequest::readDependencySource(
     const evaluator::DependencyRecorder &) const {
   auto *dc = std::get<0>(getStorage());
-  auto opts = std::get<3>(getStorage());
-  // FIXME(Evaluator Incremental Dependencies): This is an artifact of the
-  // current scheme and should be removed. There are very few callers that are
-  // accurately passing the right known dependencies mask.
-  const bool cascades =
-      dc->isCascadingContextForLookup(/*functionsAreNonCascading*/ false);
-  auto scope = evaluator::DependencyScope::Cascading;
-  if (!cascades)
-    scope = evaluator::DependencyScope::Private;
   return {
     dyn_cast<SourceFile>(dc->getModuleScopeContext()),
-    scope
+    evaluator::DependencyScope::Private
   };
 }