ASTScope: SourceFile scopes are always current

Author: slavapestov

include/swift/AST/ASTScope.h

@@ -530,12 +530,6 @@ class ASTSourceFileScope final : public ASTScopeImpl {
   ScopeCreator *const scopeCreator;
   ASTScopeImpl *insertionPoint;
 
-  /// The number of \c Decls in the \c SourceFile that were already seen.
-  /// Since parsing can be interleaved with type-checking, on every
-  /// lookup, look at creating scopes for any \c Decls beyond this number.
-  /// TODO: Unify with numberOfChildrenWhenLastExpanded
-  size_t numberOfDeclsAlreadySeen = 0;
-
   ASTSourceFileScope(SourceFile *SF, ScopeCreator *scopeCreator);
 
   std::string getClassName() const override;
@@ -560,8 +554,6 @@ class ASTSourceFileScope final : public ASTScopeImpl {
 
 protected:
   ASTScopeImpl *expandSpecifically(ScopeCreator &scopeCreator) override;
-  bool isCurrentIfWasExpanded() const override;
-  void beCurrent() override;
   bool doesExpansionOnlyAddNewDeclsAtEnd() const override;
 
   ScopeCreator &getScopeCreator() override;

lib/AST/ASTScopeCreation.cpp

@@ -1056,8 +1056,7 @@ ASTSourceFileScope::expandAScopeThatCreatesANewInsertionPoint(
   ASTScopeAssert(SF, "Must already have a SourceFile.");
   ArrayRef<Decl *> decls = SF->getTopLevelDecls();
   // Assume that decls are only added at the end, in source order
-  ArrayRef<Decl *> newDecls = decls.slice(numberOfDeclsAlreadySeen);
-  std::vector<ASTNode> newNodes(newDecls.begin(), newDecls.end());
+  std::vector<ASTNode> newNodes(decls.begin(), decls.end());
   insertionPoint =
       scopeCreator.addSiblingsToScopeTree(insertionPoint, this, newNodes);
   // Too slow to perform all the time:
@@ -1688,13 +1687,6 @@ bool ASTScopeImpl::isCurrent() const {
 void ASTScopeImpl::beCurrent() {}
 bool ASTScopeImpl::isCurrentIfWasExpanded() const { return true; }
 
-void ASTSourceFileScope::beCurrent() {
-  numberOfDeclsAlreadySeen = SF->getTopLevelDecls().size();
-}
-bool ASTSourceFileScope::isCurrentIfWasExpanded() const {
-  return SF->getTopLevelDecls().size() == numberOfDeclsAlreadySeen;
-}
-
 #pragma mark getParentOfASTAncestorScopesToBeRescued
 NullablePtr<ASTScopeImpl>
 ASTScopeImpl::getParentOfASTAncestorScopesToBeRescued() {