Implement basic visitation for nested name specifiers via libclang

cursors. Sadly, this visitation is a hack, because we don't have
proper source-location information for nested-name-specifiers in the
AST. It does improve on the status quo, however.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112837 91177308-0d34-0410-b5e6-96231b3b80d8

test/Index/load-classes.cpp

@@ -7,6 +7,9 @@ struct X {
   operator X*();
 };
 
+X::X(int value) {
+}
+
 // RUN: c-index-test -test-load-source all %s | FileCheck %s
 // CHECK: load-classes.cpp:3:8: StructDecl=X:3:8 (Definition) Extent=[3:1 - 8:2]
 // CHECK: load-classes.cpp:4:3: CXXConstructor=X:4:3 Extent=[4:3 - 4:15]
@@ -20,3 +23,6 @@ struct X {
 // FIXME: missing TypeRef in the destructor name
 // CHECK: load-classes.cpp:7:3: CXXConversion=operator struct X *:7:3 Extent=[7:3 - 7:16]
 // CHECK: load-classes.cpp:7:12: TypeRef=struct X:3:8 Extent=[7:12 - 7:13]
+// CHECK: load-classes.cpp:10:4: CXXConstructor=X:10:4 (Definition) Extent=[10:4 - 11:2]
+// CHECK: load-classes.cpp:10:1: TypeRef=struct X:3:8 Extent=[10:1 - 10:2]
+// CHECK: load-classes.cpp:10:10: ParmDecl=value:10:10 (Definition) Extent=[10:6 - 10:15]

test/Index/load-namespaces.cpp

@@ -21,6 +21,11 @@ namespace std {
 
 using std::g;
 
+void std::g() {
+}
+
+namespace my_rel_ops = std::rel_ops;
+
 // RUN: c-index-test -test-load-source all %s | FileCheck %s
 // CHECK: load-namespaces.cpp:3:11: Namespace=std:3:11 (Definition) Extent=[3:11 - 7:2]
 // CHECK: load-namespaces.cpp:4:13: Namespace=rel_ops:4:13 (Definition) Extent=[4:13 - 6:4]
@@ -37,3 +42,9 @@ using std::g;
 // CHECK: load-namespaces.cpp:19:7: FunctionDecl=g:19:7 Extent=[19:7 - 19:13]
 // CHECK: load-namespaces.cpp:19:12: ParmDecl=:19:12 (Definition) Extent=[19:9 - 19:13]
 // CHECK: load-namespaces.cpp:22:12: UsingDeclaration=g:22:12 Extent=[22:1 - 22:13]
+// CHECK: load-namespaces.cpp:22:7: NamespaceRef=std:18:11 Extent=[22:7 - 22:10]
+// CHECK: load-namespaces.cpp:24:11: FunctionDecl=g:24:11 (Definition) Extent=[24:11 - 25:2]
+// CHECK: load-namespaces.cpp:24:6: NamespaceRef=std:18:11 Extent=[24:6 - 24:9]
+// CHECK: load-namespaces.cpp:27:11: NamespaceAlias=my_rel_ops:27:11 Extent=[27:1 - 27:36]
+// CHECK: load-namespaces.cpp:27:24: NamespaceRef=std:18:11 Extent=[27:24 - 27:27]
+// CHECK: load-namespaces.cpp:27:29: NamespaceRef=rel_ops:4:13 Extent=[27:29 - 27:36]

tools/libclang/CIndex.cpp

@@ -327,6 +327,7 @@ public:
   
   // Name visitor
   bool VisitDeclarationNameInfo(DeclarationNameInfo Name);
+  bool VisitNestedNameSpecifier(NestedNameSpecifier *NNS, SourceRange Range);
   
   // Template visitors
   bool VisitTemplateParameters(const TemplateParameterList *Params);
@@ -700,7 +701,10 @@ bool CursorVisitor::VisitFunctionDecl(FunctionDecl *ND) {
         (!FTL && Visit(TL)))
       return true;
     
-    // FIXME: Visit the nested-name-specifier, if present.
+    // Visit the nested-name-specifier, if present.
+    if (NestedNameSpecifier *Qualifier = ND->getQualifier())
+      if (VisitNestedNameSpecifier(Qualifier, ND->getQualifierRange()))
+        return true;
     
     // Visit the declaration name.
     if (VisitDeclarationNameInfo(ND->getNameInfo()))
@@ -934,14 +938,20 @@ bool CursorVisitor::VisitNamespaceDecl(NamespaceDecl *D) {
 }
 
 bool CursorVisitor::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
-  // FIXME: Visit nested-name-specifier.
+  // Visit nested-name-specifier.
+  if (NestedNameSpecifier *Qualifier = D->getQualifier())
+    if (VisitNestedNameSpecifier(Qualifier, D->getQualifierRange()))
+      return true;
   
   return Visit(MakeCursorNamespaceRef(D->getAliasedNamespace(), 
                                       D->getTargetNameLoc(), TU));
 }
 
 bool CursorVisitor::VisitUsingDecl(UsingDecl *D) {
-  // FIXME: Visit nested-name-specifier.
+  // Visit nested-name-specifier.
+  if (NestedNameSpecifier *Qualifier = D->getTargetNestedNameDecl())
+    if (VisitNestedNameSpecifier(Qualifier, D->getNestedNameRange()))
+      return true;
   
   // FIXME: Provide a multi-reference of some kind for all of the declarations
   // that the using declaration refers to. We don't have this kind of cursor
@@ -951,21 +961,31 @@ bool CursorVisitor::VisitUsingDecl(UsingDecl *D) {
 }
 
 bool CursorVisitor::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
-  // FIXME: Visit nested-name-specifier.
+  // Visit nested-name-specifier.
+  if (NestedNameSpecifier *Qualifier = D->getQualifier())
+    if (VisitNestedNameSpecifier(Qualifier, D->getQualifierRange()))
+      return true;
 
   return Visit(MakeCursorNamespaceRef(D->getNominatedNamespaceAsWritten(),
                                       D->getIdentLocation(), TU));
 }
 
 bool CursorVisitor::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
-  // FIXME: Visit nested-name-specifier.
-  
+  // Visit nested-name-specifier.
+  if (NestedNameSpecifier *Qualifier = D->getTargetNestedNameSpecifier())
+    if (VisitNestedNameSpecifier(Qualifier, D->getTargetNestedNameRange()))
+      return true;
+
   return VisitDeclarationNameInfo(D->getNameInfo());
 }
 
 bool CursorVisitor::VisitUnresolvedUsingTypenameDecl(
                                                UnresolvedUsingTypenameDecl *D) {
-  // FIXME: Visit nested-name-specifier.
+  // Visit nested-name-specifier.
+  if (NestedNameSpecifier *Qualifier = D->getTargetNestedNameSpecifier())
+    if (VisitNestedNameSpecifier(Qualifier, D->getTargetNestedNameRange()))
+      return true;
+  
   return false;
 }
 
@@ -994,6 +1014,50 @@ bool CursorVisitor::VisitDeclarationNameInfo(DeclarationNameInfo Name) {
   return false;
 }
 
+bool CursorVisitor::VisitNestedNameSpecifier(NestedNameSpecifier *NNS, 
+                                             SourceRange Range) {
+  // FIXME: This whole routine is a hack to work around the lack of proper
+  // source information in nested-name-specifiers (PR5791). Since we do have
+  // a beginning source location, we can visit the first component of the
+  // nested-name-specifier, if it's a single-token component.
+  if (!NNS)
+    return false;
+  
+  // Get the first component in the nested-name-specifier.
+  while (NestedNameSpecifier *Prefix = NNS->getPrefix())
+    NNS = Prefix;
+  
+  switch (NNS->getKind()) {
+  case NestedNameSpecifier::Namespace:
+    // FIXME: The token at this source location might actually have been a
+    // namespace alias, but we don't model that. Lame!
+    return Visit(MakeCursorNamespaceRef(NNS->getAsNamespace(), Range.getBegin(),
+                                        TU));
+
+  case NestedNameSpecifier::TypeSpec: {
+    // If the type has a form where we know that the beginning of the source
+    // range matches up with a reference cursor. Visit the appropriate reference
+    // cursor.
+    Type *T = NNS->getAsType();
+    if (const TypedefType *Typedef = dyn_cast<TypedefType>(T))
+      return Visit(MakeCursorTypeRef(Typedef->getDecl(), Range.getBegin(), TU));
+    if (const TagType *Tag = dyn_cast<TagType>(T))
+      return Visit(MakeCursorTypeRef(Tag->getDecl(), Range.getBegin(), TU));
+    if (const TemplateSpecializationType *TST
+                                      = dyn_cast<TemplateSpecializationType>(T))
+      return VisitTemplateName(TST->getTemplateName(), Range.getBegin());
+    break;
+  }
+      
+  case NestedNameSpecifier::TypeSpecWithTemplate:
+  case NestedNameSpecifier::Global:
+  case NestedNameSpecifier::Identifier:
+    break;      
+  }
+  
+  return false;
+}
+
 bool CursorVisitor::VisitTemplateParameters(
                                           const TemplateParameterList *Params) {
   if (!Params)