Rename shouldVisitImplicitDeclarations to shouldVisitImplicitCode.

Fix RecursiveASTVisitor to visit CXXForRangeStmts accordingly to visit
implicit or explicit code.

The key bug that inspired this was the Visitor not visiting the range
initializer of such a loop, which is explicit code.

llvm-svn: 158395

2 files changed, 38 insertions, 6 deletions

diff --git a/clang/include/clang/AST/RecursiveASTVisitor.h b/clang/include/clang/AST/RecursiveASTVisitor.h
index de042cafb6d..2014f071523 100644
--- a/clang/include/clang/AST/RecursiveASTVisitor.h
+++ b/clang/include/clang/AST/RecursiveASTVisitor.h
@@ -149,8 +149,8 @@ public:
   bool shouldWalkTypesOfTypeLocs() const { return true; }
 
   /// \brief Return whether this visitor should recurse into implicit
-  /// declarations, e.g., implicit constructors and destructors.
-  bool shouldVisitImplicitDeclarations() const { return false; }
+  /// code, e.g., implicit constructors and destructors.
+  bool shouldVisitImplicitCode() const { return false; }
 
   /// \brief Return whether \param S should be traversed using data recursion
   /// to avoid a stack overflow with extreme cases.
@@ -607,7 +607,7 @@ bool RecursiveASTVisitor<Derived>::TraverseDecl(Decl *D) {
 
   // As a syntax visitor, by default we want to ignore declarations for
   // implicit declarations (ones not typed explicitly by the user).
-  if (!getDerived().shouldVisitImplicitDeclarations() && D->isImplicit())
+  if (!getDerived().shouldVisitImplicitCode() && D->isImplicit())
     return true;
 
   switch (D->getKind()) {
@@ -1755,7 +1755,8 @@ template<typename Derived>
 bool RecursiveASTVisitor<Derived>::TraverseVarHelper(VarDecl *D) {
   TRY_TO(TraverseDeclaratorHelper(D));
   // Default params are taken care of when we traverse the ParmVarDecl.
-  if (!isa<ParmVarDecl>(D))
+  if (!isa<ParmVarDecl>(D) &&
+      (!D->isCXXForRangeDecl() || shouldVisitImplicitCode()))
     TRY_TO(TraverseStmt(D->getInit()));
   return true;
 }
@@ -1873,7 +1874,14 @@ DEF_TRAVERSE_STMT(ObjCAtThrowStmt, { })
 DEF_TRAVERSE_STMT(ObjCAtTryStmt, { })
 DEF_TRAVERSE_STMT(ObjCForCollectionStmt, { })
 DEF_TRAVERSE_STMT(ObjCAutoreleasePoolStmt, { })
-DEF_TRAVERSE_STMT(CXXForRangeStmt, { })
+DEF_TRAVERSE_STMT(CXXForRangeStmt, {
+  if (!shouldVisitImplicitCode()) {
+    TRY_TO(TraverseStmt(S->getLoopVarStmt()));
+    TRY_TO(TraverseStmt(S->getRangeInit()));
+    // Visit everything else only if shouldVisitImplicitCode().
+    return true;
+  }
+})
 DEF_TRAVERSE_STMT(MSDependentExistsStmt, {
     TRY_TO(TraverseNestedNameSpecifierLoc(S->getQualifierLoc()));
     TRY_TO(TraverseDeclarationNameInfo(S->getNameInfo()));
diff --git a/clang/unittests/Tooling/RecursiveASTVisitorTest.cpp b/clang/unittests/Tooling/RecursiveASTVisitorTest.cpp
index 52b3987bc84..9d693095d7c 100644
--- a/clang/unittests/Tooling/RecursiveASTVisitorTest.cpp
+++ b/clang/unittests/Tooling/RecursiveASTVisitorTest.cpp
@@ -142,6 +142,14 @@ public:
   }
 };
 
+class VarDeclVisitor : public ExpectedLocationVisitor<VarDeclVisitor> {
+public:
+ bool VisitVarDecl(VarDecl *Variable) {
+   Match(Variable->getNameAsString(), Variable->getLocStart());
+   return true;
+ }
+};
+
 class CXXMemberCallVisitor
   : public ExpectedLocationVisitor<CXXMemberCallVisitor> {
 public:
@@ -250,6 +258,22 @@ TEST(RecursiveASTVisitor, VisitsBaseClassTemplateArguments) {
     "void x(); template <void (*T)()> class X {};\nX<x> y;"));
 }
 
+TEST(RecursiveASTVisitor, VisitsCXXForRangeStmtRange) {
+  DeclRefExprVisitor Visitor;
+  Visitor.ExpectMatch("x", 2, 25);
+  EXPECT_TRUE(Visitor.runOver(
+    "int x[5];\n"
+    "void f() { for (int i : x) {} }"));
+}
+
+TEST(RecursiveASTVisitor, VisitsCXXForRangeStmtLoopVariable) {
+  VarDeclVisitor Visitor;
+  Visitor.ExpectMatch("i", 2, 17);
+  EXPECT_TRUE(Visitor.runOver(
+    "int x[5];\n"
+    "void f() { for (int i : x) {} }"));
+}
+
 TEST(RecursiveASTVisitor, VisitsCallExpr) {
   DeclRefExprVisitor Visitor;
   Visitor.ExpectMatch("x", 1, 22);
@@ -452,7 +476,7 @@ TEST(RecursiveASTVisitor, VisitsClassTemplateTemplateParmDefaultArgument) {
 class ImplicitCtorVisitor
     : public ExpectedLocationVisitor<ImplicitCtorVisitor> {
 public:
-  bool shouldVisitImplicitDeclarations() const { return true; }
+  bool shouldVisitImplicitCode() const { return true; }
 
   bool VisitCXXConstructorDecl(CXXConstructorDecl* Ctor) {
     if (Ctor->isImplicit()) {  // Was not written in source code