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-rw-r--r--include/clang/AST/ASTContext.h38
-rw-r--r--include/clang/AST/RecursiveASTVisitor.h10
-rw-r--r--lib/AST/ASTContext.cpp329
-rw-r--r--lib/ASTMatchers/ASTMatchFinder.cpp23
-rw-r--r--unittests/AST/ASTContextParentMapTest.cpp28
-rw-r--r--unittests/Tooling/CMakeLists.txt1
-rw-r--r--unittests/Tooling/RecursiveASTVisitorTests/TraversalScope.cpp51
7 files changed, 289 insertions, 191 deletions
diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index b90552596e..7edf3b3fed 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -569,26 +569,6 @@ public:
IntrusiveRefCntPtr<ExternalASTSource> ExternalSource;
ASTMutationListener *Listener = nullptr;
- /// Contains parents of a node.
- using ParentVector = llvm::SmallVector<ast_type_traits::DynTypedNode, 2>;
-
- /// Maps from a node to its parents. This is used for nodes that have
- /// pointer identity only, which are more common and we can save space by
- /// only storing a unique pointer to them.
- using ParentMapPointers =
- llvm::DenseMap<const void *,
- llvm::PointerUnion4<const Decl *, const Stmt *,
- ast_type_traits::DynTypedNode *,
- ParentVector *>>;
-
- /// Parent map for nodes without pointer identity. We store a full
- /// DynTypedNode for all keys.
- using ParentMapOtherNodes =
- llvm::DenseMap<ast_type_traits::DynTypedNode,
- llvm::PointerUnion4<const Decl *, const Stmt *,
- ast_type_traits::DynTypedNode *,
- ParentVector *>>;
-
/// Container for either a single DynTypedNode or for an ArrayRef to
/// DynTypedNode. For use with ParentMap.
class DynTypedNodeList {
@@ -630,7 +610,17 @@ public:
}
};
- /// Returns the parents of the given node.
+ // A traversal scope limits the parts of the AST visible to certain analyses.
+ // RecursiveASTVisitor::TraverseAST will only visit reachable nodes, and
+ // getParents() will only observe reachable parent edges.
+ //
+ // The scope is defined by a set of "top-level" declarations.
+ // Initially, it is the entire TU: {getTranslationUnitDecl()}.
+ // Changing the scope clears the parent cache, which is expensive to rebuild.
+ std::vector<Decl *> getTraversalScope() const { return TraversalScope; }
+ void setTraversalScope(const std::vector<Decl *> &);
+
+ /// Returns the parents of the given node (within the traversal scope).
///
/// Note that this will lazily compute the parents of all nodes
/// and store them for later retrieval. Thus, the first call is O(n)
@@ -2924,13 +2914,13 @@ private:
// but we include it here so that ASTContext can quickly deallocate them.
llvm::PointerIntPair<StoredDeclsMap *, 1> LastSDM;
- std::unique_ptr<ParentMapPointers> PointerParents;
- std::unique_ptr<ParentMapOtherNodes> OtherParents;
+ std::vector<Decl *> TraversalScope;
+ class ParentMap;
+ std::unique_ptr<ParentMap> Parents;
std::unique_ptr<VTableContextBase> VTContext;
void ReleaseDeclContextMaps();
- void ReleaseParentMapEntries();
public:
enum PragmaSectionFlag : unsigned {
diff --git a/include/clang/AST/RecursiveASTVisitor.h b/include/clang/AST/RecursiveASTVisitor.h
index c2a13df652..eb582c7a7a 100644
--- a/include/clang/AST/RecursiveASTVisitor.h
+++ b/include/clang/AST/RecursiveASTVisitor.h
@@ -176,6 +176,16 @@ public:
/// Return whether this visitor should traverse post-order.
bool shouldTraversePostOrder() const { return false; }
+ /// Recursively visits an entire AST, starting from the top-level Decls
+ /// in the AST traversal scope (by default, the TranslationUnitDecl).
+ /// \returns false if visitation was terminated early.
+ bool TraverseAST(ASTContext &AST) {
+ for (Decl *D : AST.getTraversalScope())
+ if (!getDerived().TraverseDecl(D))
+ return false;
+ return true;
+ }
+
/// Recursively visit a statement or expression, by
/// dispatching to Traverse*() based on the argument's dynamic type.
///
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 33c5b50f66..1ac46f897c 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -796,11 +796,10 @@ ASTContext::ASTContext(LangOptions &LOpts, SourceManager &SM,
CommentCommandTraits(BumpAlloc, LOpts.CommentOpts),
CompCategories(this_()), LastSDM(nullptr, 0) {
TUDecl = TranslationUnitDecl::Create(*this);
+ TraversalScope = {TUDecl};
}
ASTContext::~ASTContext() {
- ReleaseParentMapEntries();
-
// Release the DenseMaps associated with DeclContext objects.
// FIXME: Is this the ideal solution?
ReleaseDeclContextMaps();
@@ -838,22 +837,80 @@ ASTContext::~ASTContext() {
Value.second->~PerModuleInitializers();
}
-void ASTContext::ReleaseParentMapEntries() {
- if (!PointerParents) return;
- for (const auto &Entry : *PointerParents) {
- if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
- delete Entry.second.get<ast_type_traits::DynTypedNode *>();
- } else if (Entry.second.is<ParentVector *>()) {
- delete Entry.second.get<ParentVector *>();
+class ASTContext::ParentMap {
+ /// Contains parents of a node.
+ using ParentVector = llvm::SmallVector<ast_type_traits::DynTypedNode, 2>;
+
+ /// Maps from a node to its parents. This is used for nodes that have
+ /// pointer identity only, which are more common and we can save space by
+ /// only storing a unique pointer to them.
+ using ParentMapPointers = llvm::DenseMap<
+ const void *,
+ llvm::PointerUnion4<const Decl *, const Stmt *,
+ ast_type_traits::DynTypedNode *, ParentVector *>>;
+
+ /// Parent map for nodes without pointer identity. We store a full
+ /// DynTypedNode for all keys.
+ using ParentMapOtherNodes = llvm::DenseMap<
+ ast_type_traits::DynTypedNode,
+ llvm::PointerUnion4<const Decl *, const Stmt *,
+ ast_type_traits::DynTypedNode *, ParentVector *>>;
+
+ ParentMapPointers PointerParents;
+ ParentMapOtherNodes OtherParents;
+ class ASTVisitor;
+
+ static ast_type_traits::DynTypedNode
+ getSingleDynTypedNodeFromParentMap(ParentMapPointers::mapped_type U) {
+ if (const auto *D = U.dyn_cast<const Decl *>())
+ return ast_type_traits::DynTypedNode::create(*D);
+ if (const auto *S = U.dyn_cast<const Stmt *>())
+ return ast_type_traits::DynTypedNode::create(*S);
+ return *U.get<ast_type_traits::DynTypedNode *>();
+ }
+
+ template <typename NodeTy, typename MapTy>
+ static ASTContext::DynTypedNodeList getDynNodeFromMap(const NodeTy &Node,
+ const MapTy &Map) {
+ auto I = Map.find(Node);
+ if (I == Map.end()) {
+ return llvm::ArrayRef<ast_type_traits::DynTypedNode>();
+ }
+ if (const auto *V = I->second.template dyn_cast<ParentVector *>()) {
+ return llvm::makeArrayRef(*V);
+ }
+ return getSingleDynTypedNodeFromParentMap(I->second);
+ }
+
+public:
+ ParentMap(ASTContext &Ctx);
+ ~ParentMap() {
+ for (const auto &Entry : PointerParents) {
+ if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
+ delete Entry.second.get<ast_type_traits::DynTypedNode *>();
+ } else if (Entry.second.is<ParentVector *>()) {
+ delete Entry.second.get<ParentVector *>();
+ }
}
- }
- for (const auto &Entry : *OtherParents) {
- if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
- delete Entry.second.get<ast_type_traits::DynTypedNode *>();
- } else if (Entry.second.is<ParentVector *>()) {
- delete Entry.second.get<ParentVector *>();
+ for (const auto &Entry : OtherParents) {
+ if (Entry.second.is<ast_type_traits::DynTypedNode *>()) {
+ delete Entry.second.get<ast_type_traits::DynTypedNode *>();
+ } else if (Entry.second.is<ParentVector *>()) {
+ delete Entry.second.get<ParentVector *>();
+ }
}
}
+
+ DynTypedNodeList getParents(const ast_type_traits::DynTypedNode &Node) {
+ if (Node.getNodeKind().hasPointerIdentity())
+ return getDynNodeFromMap(Node.getMemoizationData(), PointerParents);
+ return getDynNodeFromMap(Node, OtherParents);
+ }
+};
+
+void ASTContext::setTraversalScope(const std::vector<Decl *> &TopLevelDecls) {
+ TraversalScope = TopLevelDecls;
+ Parents.reset();
}
void ASTContext::AddDeallocation(void (*Callback)(void*), void *Data) {
@@ -10104,21 +10161,10 @@ bool ASTContext::AtomicUsesUnsupportedLibcall(const AtomicExpr *E) const {
return (Size != Align || toBits(sizeChars) > MaxInlineWidthInBits);
}
-static ast_type_traits::DynTypedNode getSingleDynTypedNodeFromParentMap(
- ASTContext::ParentMapPointers::mapped_type U) {
- if (const auto *D = U.dyn_cast<const Decl *>())
- return ast_type_traits::DynTypedNode::create(*D);
- if (const auto *S = U.dyn_cast<const Stmt *>())
- return ast_type_traits::DynTypedNode::create(*S);
- return *U.get<ast_type_traits::DynTypedNode *>();
-}
-
-namespace {
-
/// Template specializations to abstract away from pointers and TypeLocs.
/// @{
template <typename T>
-ast_type_traits::DynTypedNode createDynTypedNode(const T &Node) {
+static ast_type_traits::DynTypedNode createDynTypedNode(const T &Node) {
return ast_type_traits::DynTypedNode::create(*Node);
}
template <>
@@ -10132,160 +10178,121 @@ createDynTypedNode(const NestedNameSpecifierLoc &Node) {
}
/// @}
- /// A \c RecursiveASTVisitor that builds a map from nodes to their
- /// parents as defined by the \c RecursiveASTVisitor.
- ///
- /// Note that the relationship described here is purely in terms of AST
- /// traversal - there are other relationships (for example declaration context)
- /// in the AST that are better modeled by special matchers.
- ///
- /// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
- class ParentMapASTVisitor : public RecursiveASTVisitor<ParentMapASTVisitor> {
- public:
- /// Builds and returns the translation unit's parent map.
- ///
- /// The caller takes ownership of the returned \c ParentMap.
- static std::pair<ASTContext::ParentMapPointers *,
- ASTContext::ParentMapOtherNodes *>
- buildMap(TranslationUnitDecl &TU) {
- ParentMapASTVisitor Visitor(new ASTContext::ParentMapPointers,
- new ASTContext::ParentMapOtherNodes);
- Visitor.TraverseDecl(&TU);
- return std::make_pair(Visitor.Parents, Visitor.OtherParents);
- }
+/// A \c RecursiveASTVisitor that builds a map from nodes to their
+/// parents as defined by the \c RecursiveASTVisitor.
+///
+/// Note that the relationship described here is purely in terms of AST
+/// traversal - there are other relationships (for example declaration context)
+/// in the AST that are better modeled by special matchers.
+///
+/// FIXME: Currently only builds up the map using \c Stmt and \c Decl nodes.
+class ASTContext::ParentMap::ASTVisitor
+ : public RecursiveASTVisitor<ASTVisitor> {
+public:
+ ASTVisitor(ParentMap &Map) : Map(Map) {}
- private:
- friend class RecursiveASTVisitor<ParentMapASTVisitor>;
+private:
+ friend class RecursiveASTVisitor<ASTVisitor>;
- using VisitorBase = RecursiveASTVisitor<ParentMapASTVisitor>;
+ using VisitorBase = RecursiveASTVisitor<ASTVisitor>;
- ParentMapASTVisitor(ASTContext::ParentMapPointers *Parents,
- ASTContext::ParentMapOtherNodes *OtherParents)
- : Parents(Parents), OtherParents(OtherParents) {}
+ bool shouldVisitTemplateInstantiations() const { return true; }
- bool shouldVisitTemplateInstantiations() const {
- return true;
- }
+ bool shouldVisitImplicitCode() const { return true; }
- bool shouldVisitImplicitCode() const {
+ template <typename T, typename MapNodeTy, typename BaseTraverseFn,
+ typename MapTy>
+ bool TraverseNode(T Node, MapNodeTy MapNode, BaseTraverseFn BaseTraverse,
+ MapTy *Parents) {
+ if (!Node)
return true;
- }
-
- template <typename T, typename MapNodeTy, typename BaseTraverseFn,
- typename MapTy>
- bool TraverseNode(T Node, MapNodeTy MapNode,
- BaseTraverseFn BaseTraverse, MapTy *Parents) {
- if (!Node)
- return true;
- if (ParentStack.size() > 0) {
- // FIXME: Currently we add the same parent multiple times, but only
- // when no memoization data is available for the type.
- // For example when we visit all subexpressions of template
- // instantiations; this is suboptimal, but benign: the only way to
- // visit those is with hasAncestor / hasParent, and those do not create
- // new matches.
- // The plan is to enable DynTypedNode to be storable in a map or hash
- // map. The main problem there is to implement hash functions /
- // comparison operators for all types that DynTypedNode supports that
- // do not have pointer identity.
- auto &NodeOrVector = (*Parents)[MapNode];
- if (NodeOrVector.isNull()) {
- if (const auto *D = ParentStack.back().get<Decl>())
- NodeOrVector = D;
- else if (const auto *S = ParentStack.back().get<Stmt>())
- NodeOrVector = S;
- else
- NodeOrVector =
- new ast_type_traits::DynTypedNode(ParentStack.back());
- } else {
- if (!NodeOrVector.template is<ASTContext::ParentVector *>()) {
- auto *Vector = new ASTContext::ParentVector(
- 1, getSingleDynTypedNodeFromParentMap(NodeOrVector));
- delete NodeOrVector
- .template dyn_cast<ast_type_traits::DynTypedNode *>();
- NodeOrVector = Vector;
- }
-
- auto *Vector =
- NodeOrVector.template get<ASTContext::ParentVector *>();
- // Skip duplicates for types that have memoization data.
- // We must check that the type has memoization data before calling
- // std::find() because DynTypedNode::operator== can't compare all
- // types.
- bool Found = ParentStack.back().getMemoizationData() &&
- std::find(Vector->begin(), Vector->end(),
- ParentStack.back()) != Vector->end();
- if (!Found)
- Vector->push_back(ParentStack.back());
+ if (ParentStack.size() > 0) {
+ // FIXME: Currently we add the same parent multiple times, but only
+ // when no memoization data is available for the type.
+ // For example when we visit all subexpressions of template
+ // instantiations; this is suboptimal, but benign: the only way to
+ // visit those is with hasAncestor / hasParent, and those do not create
+ // new matches.
+ // The plan is to enable DynTypedNode to be storable in a map or hash
+ // map. The main problem there is to implement hash functions /
+ // comparison operators for all types that DynTypedNode supports that
+ // do not have pointer identity.
+ auto &NodeOrVector = (*Parents)[MapNode];
+ if (NodeOrVector.isNull()) {
+ if (const auto *D = ParentStack.back().get<Decl>())
+ NodeOrVector = D;
+ else if (const auto *S = ParentStack.back().get<Stmt>())
+ NodeOrVector = S;
+ else
+ NodeOrVector = new ast_type_traits::DynTypedNode(ParentStack.back());
+ } else {
+ if (!NodeOrVector.template is<ParentVector *>()) {
+ auto *Vector = new ParentVector(
+ 1, getSingleDynTypedNodeFromParentMap(NodeOrVector));
+ delete NodeOrVector
+ .template dyn_cast<ast_type_traits::DynTypedNode *>();
+ NodeOrVector = Vector;
}
- }
- ParentStack.push_back(createDynTypedNode(Node));
- bool Result = BaseTraverse();
- ParentStack.pop_back();
- return Result;
- }
- bool TraverseDecl(Decl *DeclNode) {
- return TraverseNode(DeclNode, DeclNode,
- [&] { return VisitorBase::TraverseDecl(DeclNode); },
- Parents);
+ auto *Vector = NodeOrVector.template get<ParentVector *>();
+ // Skip duplicates for types that have memoization data.
+ // We must check that the type has memoization data before calling
+ // std::find() because DynTypedNode::operator== can't compare all
+ // types.
+ bool Found = ParentStack.back().getMemoizationData() &&
+ std::find(Vector->begin(), Vector->end(),
+ ParentStack.back()) != Vector->end();
+ if (!Found)
+ Vector->push_back(ParentStack.back());
+ }
}
+ ParentStack.push_back(createDynTypedNode(Node));
+ bool Result = BaseTraverse();
+ ParentStack.pop_back();
+ return Result;
+ }
- bool TraverseStmt(Stmt *StmtNode) {
- return TraverseNode(StmtNode, StmtNode,
- [&] { return VisitorBase::TraverseStmt(StmtNode); },
- Parents);
- }
+ bool TraverseDecl(Decl *DeclNode) {
+ return TraverseNode(
+ DeclNode, DeclNode, [&] { return VisitorBase::TraverseDecl(DeclNode); },
+ &Map.PointerParents);
+ }
- bool TraverseTypeLoc(TypeLoc TypeLocNode) {
- return TraverseNode(
- TypeLocNode, ast_type_traits::DynTypedNode::create(TypeLocNode),
- [&] { return VisitorBase::TraverseTypeLoc(TypeLocNode); },
- OtherParents);
- }
+ bool TraverseStmt(Stmt *StmtNode) {
+ return TraverseNode(
+ StmtNode, StmtNode, [&] { return VisitorBase::TraverseStmt(StmtNode); },
+ &Map.PointerParents);
+ }
- bool TraverseNestedNameSpecifierLoc(NestedNameSpecifierLoc NNSLocNode) {
- return TraverseNode(
- NNSLocNode, ast_type_traits::DynTypedNode::create(NNSLocNode),
- [&] {
- return VisitorBase::TraverseNestedNameSpecifierLoc(NNSLocNode);
- },
- OtherParents);
- }
+ bool TraverseTypeLoc(TypeLoc TypeLocNode) {
+ return TraverseNode(
+ TypeLocNode, ast_type_traits::DynTypedNode::create(TypeLocNode),
+ [&] { return VisitorBase::TraverseTypeLoc(TypeLocNode); },
+ &Map.OtherParents);
+ }
- ASTContext::ParentMapPointers *Parents;
- ASTContext::ParentMapOtherNodes *OtherParents;
- llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
- };
+ bool TraverseNestedNameSpecifierLoc(NestedNameSpecifierLoc NNSLocNode) {
+ return TraverseNode(
+ NNSLocNode, ast_type_traits::DynTypedNode::create(NNSLocNode),
+ [&] { return VisitorBase::TraverseNestedNameSpecifierLoc(NNSLocNode); },
+ &Map.OtherParents);
+ }
-} // namespace
+ ParentMap &Map;
+ llvm::SmallVector<ast_type_traits::DynTypedNode, 16> ParentStack;
+};
-template <typename NodeTy, typename MapTy>
-static ASTContext::DynTypedNodeList getDynNodeFromMap(const NodeTy &Node,
- const MapTy &Map) {
- auto I = Map.find(Node);
- if (I == Map.end()) {
- return llvm::ArrayRef<ast_type_traits::DynTypedNode>();
- }
- if (const auto *V =
- I->second.template dyn_cast<ASTContext::ParentVector *>()) {
- return llvm::makeArrayRef(*V);
- }
- return getSingleDynTypedNodeFromParentMap(I->second);
+ASTContext::ParentMap::ParentMap(ASTContext &Ctx) {
+ ASTVisitor(*this).TraverseAST(Ctx);
}
ASTContext::DynTypedNodeList
ASTContext::getParents(const ast_type_traits::DynTypedNode &Node) {
- if (!PointerParents) {
- // We always need to run over the whole translation unit, as
+ if (!Parents)
+ // We build the parent map for the traversal scope (usually whole TU), as
// hasAncestor can escape any subtree.
- auto Maps = ParentMapASTVisitor::buildMap(*getTranslationUnitDecl());
- PointerParents.reset(Maps.first);
- OtherParents.reset(Maps.second);
- }
- if (Node.getNodeKind().hasPointerIdentity())
- return getDynNodeFromMap(Node.getMemoizationData(), *PointerParents);
- return getDynNodeFromMap(Node, *OtherParents);
+ Parents = llvm::make_unique<ParentMap>(*this);
+ return Parents->getParents(Node);
}
bool
diff --git a/lib/ASTMatchers/ASTMatchFinder.cpp b/lib/ASTMatchers/ASTMatchFinder.cpp
index 63f8395b82..8d65714317 100644
--- a/lib/ASTMatchers/ASTMatchFinder.cpp
+++ b/lib/ASTMatchers/ASTMatchFinder.cpp
@@ -635,10 +635,6 @@ private:
bool memoizedMatchesAncestorOfRecursively(
const ast_type_traits::DynTypedNode &Node, const DynTypedMatcher &Matcher,
BoundNodesTreeBuilder *Builder, AncestorMatchMode MatchMode) {
- if (Node.get<TranslationUnitDecl>() ==
- ActiveASTContext->getTranslationUnitDecl())
- return false;
-
// For AST-nodes that don't have an identity, we can't memoize.
if (!Builder->isComparable())
return matchesAncestorOfRecursively(Node, Matcher, Builder, MatchMode);
@@ -673,7 +669,22 @@ private:
BoundNodesTreeBuilder *Builder,
AncestorMatchMode MatchMode) {
const auto &Parents = ActiveASTContext->getParents(Node);
- assert(!Parents.empty() && "Found node that is not in the parent map.");
+ if (Parents.empty()) {
+ // Nodes may have no parents if:
+ // a) the node is the TranslationUnitDecl
+ // b) we have a limited traversal scope that excludes the parent edges
+ // c) there is a bug in the AST, and the node is not reachable
+ // Usually the traversal scope is the whole AST, which precludes b.
+ // Bugs are common enough that it's worthwhile asserting when we can.
+ assert(Node.get<TranslationUnitDecl>() ||
+ /* Traversal scope is limited if none of the bounds are the TU */
+ llvm::none_of(ActiveASTContext->getTraversalScope(),
+ [](Decl *D) {
+ return D->getKind() == Decl::TranslationUnit;
+ }) &&
+ "Found node that is not in the complete parent map!");
+ return false;
+ }
if (Parents.size() == 1) {
// Only one parent - do recursive memoization.
const ast_type_traits::DynTypedNode Parent = Parents[0];
@@ -1019,7 +1030,7 @@ void MatchFinder::matchAST(ASTContext &Context) {
internal::MatchASTVisitor Visitor(&Matchers, Options);
Visitor.set_active_ast_context(&Context);
Visitor.onStartOfTranslationUnit();
- Visitor.TraverseDecl(Context.getTranslationUnitDecl());
+ Visitor.TraverseAST(Context);
Visitor.onEndOfTranslationUnit();
}
diff --git a/unittests/AST/ASTContextParentMapTest.cpp b/unittests/AST/ASTContextParentMapTest.cpp
index a39189620b..f06f32bf76 100644
--- a/unittests/AST/ASTContextParentMapTest.cpp
+++ b/unittests/AST/ASTContextParentMapTest.cpp
@@ -17,6 +17,9 @@
#include "clang/ASTMatchers/ASTMatchers.h"
#include "clang/Tooling/Tooling.h"
#include "gtest/gtest.h"
+#include "gmock/gmock.h"
+
+using testing::ElementsAre;
namespace clang {
namespace ast_matchers {
@@ -78,5 +81,30 @@ TEST(GetParents, ReturnsMultipleParentsInTemplateInstantiations) {
hasAncestor(cxxRecordDecl(unless(isTemplateInstantiation())))))));
}
+TEST(GetParents, RespectsTraversalScope) {
+ auto AST =
+ tooling::buildASTFromCode("struct foo { int bar; };", "foo.cpp",
+ std::make_shared<PCHContainerOperations>());
+ auto &Ctx = AST->getASTContext();
+ auto &TU = *Ctx.getTranslationUnitDecl();
+ auto &Foo = *TU.lookup(&Ctx.Idents.get("foo")).front();
+ auto &Bar = *cast<DeclContext>(Foo).lookup(&Ctx.Idents.get("bar")).front();
+
+ using ast_type_traits::DynTypedNode;
+ // Initially, scope is the whole TU.
+ EXPECT_THAT(Ctx.getParents(Bar), ElementsAre(DynTypedNode::create(Foo)));
+ EXPECT_THAT(Ctx.getParents(Foo), ElementsAre(DynTypedNode::create(TU)));
+
+ // Restrict the scope, now some parents are gone.
+ Ctx.setTraversalScope({&Foo});
+ EXPECT_THAT(Ctx.getParents(Bar), ElementsAre(DynTypedNode::create(Foo)));
+ EXPECT_THAT(Ctx.getParents(Foo), ElementsAre());
+
+ // Reset the scope, we get back the original results.
+ Ctx.setTraversalScope({&TU});
+ EXPECT_THAT(Ctx.getParents(Bar), ElementsAre(DynTypedNode::create(Foo)));
+ EXPECT_THAT(Ctx.getParents(Foo), ElementsAre(DynTypedNode::create(TU)));
+}
+
} // end namespace ast_matchers
} // end namespace clang
diff --git a/unittests/Tooling/CMakeLists.txt b/unittests/Tooling/CMakeLists.txt
index e9910fb87a..823971a242 100644
--- a/unittests/Tooling/CMakeLists.txt
+++ b/unittests/Tooling/CMakeLists.txt
@@ -40,6 +40,7 @@ add_clang_unittest(ToolingTests
RecursiveASTVisitorTests/NestedNameSpecifiers.cpp
RecursiveASTVisitorTests/ParenExpr.cpp
RecursiveASTVisitorTests/TemplateArgumentLocTraverser.cpp
+ RecursiveASTVisitorTests/TraversalScope.cpp
RecursiveASTVisitorTestDeclVisitor.cpp
RecursiveASTVisitorTestPostOrderVisitor.cpp
RecursiveASTVisitorTestTypeLocVisitor.cpp
diff --git a/unittests/Tooling/RecursiveASTVisitorTests/TraversalScope.cpp b/unittests/Tooling/RecursiveASTVisitorTests/TraversalScope.cpp
new file mode 100644
index 0000000000..72f6c644b3
--- /dev/null
+++ b/unittests/Tooling/RecursiveASTVisitorTests/TraversalScope.cpp
@@ -0,0 +1,51 @@
+//===- unittest/Tooling/RecursiveASTVisitorTests/TraversalScope.cpp -------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "TestVisitor.h"
+
+using namespace clang;
+
+namespace {
+
+class Visitor : public ExpectedLocationVisitor<Visitor, clang::TestVisitor> {
+public:
+ Visitor(ASTContext *Context) { this->Context = Context; }
+
+ bool VisitNamedDecl(NamedDecl *D) {
+ if (!D->isImplicit())
+ Match(D->getName(), D->getLocation());
+ return true;
+ }
+};
+
+TEST(RecursiveASTVisitor, RespectsTraversalScope) {
+ auto AST = tooling::buildASTFromCode(
+ R"cpp(
+struct foo {
+ struct bar {
+ struct baz {};
+ };
+};
+ )cpp",
+ "foo.cpp", std::make_shared<PCHContainerOperations>());
+ auto &Ctx = AST->getASTContext();
+ auto &TU = *Ctx.getTranslationUnitDecl();
+ auto &Foo = *TU.lookup(&Ctx.Idents.get("foo")).front();
+ auto &Bar = *cast<DeclContext>(Foo).lookup(&Ctx.Idents.get("bar")).front();
+
+ Ctx.setTraversalScope({&Bar});
+
+ Visitor V(&Ctx);
+ V.DisallowMatch("foo", 2, 8);
+ V.ExpectMatch("bar", 3, 10);
+ V.ExpectMatch("baz", 4, 12);
+ V.TraverseAST(Ctx);
+}
+
+} // end anonymous namespace