Implement libclang support for using declarations. Clang actually uses

three different kinds of AST nodes to represent using declarations:
UsingDecl, UnresolvedUsingValueDecl, and
UnresolvedUsingTypenameDecl. These three are collapsed into a single
cursor kind for using declarations, since libclang clients don't need
the distinction.

Several related changes here:
  - Cursor visitation of the three AST nodes for using declarations
  - Proper source-range computation for these AST nodes
  - Using declarations have no USRs, since they don't actually declare
    any entities.

llvm-svn: 112730

9 files changed, 99 insertions, 22 deletions

diff --git a/clang/include/clang-c/Index.h b/clang/include/clang-c/Index.h
index 0716f82eaf6..d5e3373b91d 100644
--- a/clang/include/clang-c/Index.h
+++ b/clang/include/clang-c/Index.h
@@ -998,9 +998,11 @@ enum CXCursorKind {
   CXCursor_NamespaceAlias                = 33,
   /** \brief A C++ using directive. */
   CXCursor_UsingDirective                = 34,
+  /** \brief A using declaration. */
+  CXCursor_UsingDeclaration              = 35,
   
   CXCursor_FirstDecl                     = CXCursor_UnexposedDecl,
-  CXCursor_LastDecl                      = CXCursor_UsingDirective,
+  CXCursor_LastDecl                      = CXCursor_UsingDeclaration,
 
   /* References */
   CXCursor_FirstRef                      = 40, /* Decl references */
diff --git a/clang/include/clang/AST/DeclCXX.h b/clang/include/clang/AST/DeclCXX.h
index f5cbfd0d597..a9802bfcaf4 100644
--- a/clang/include/clang/AST/DeclCXX.h
+++ b/clang/include/clang/AST/DeclCXX.h
@@ -2060,6 +2060,10 @@ public:
                            const DeclarationNameInfo &NameInfo,
                            bool IsTypeNameArg);
 
+  SourceRange getSourceRange() const {
+    return SourceRange(UsingLocation, getNameInfo().getEndLoc());
+  }
+
   static bool classof(const Decl *D) { return classofKind(D->getKind()); }
   static bool classof(const UsingDecl *D) { return true; }
   static bool classofKind(Kind K) { return K == Using; }
@@ -2134,6 +2138,10 @@ public:
            SourceRange TargetNNR, NestedNameSpecifier *TargetNNS,
            const DeclarationNameInfo &NameInfo);
 
+  SourceRange getSourceRange() const {
+    return SourceRange(UsingLocation, getNameInfo().getEndLoc());
+  }
+
   static bool classof(const Decl *D) { return classofKind(D->getKind()); }
   static bool classof(const UnresolvedUsingValueDecl *D) { return true; }
   static bool classofKind(Kind K) { return K == UnresolvedUsingValue; }
@@ -2170,43 +2178,34 @@ class UnresolvedUsingTypenameDecl : public TypeDecl {
     TypenameLocation(TypenameLoc), TargetNestedNameSpecifier(TargetNNS)
   { }
 
+  friend class ASTDeclReader;
+  
 public:
   /// \brief Returns the source range that covers the nested-name-specifier
   /// preceding the namespace name.
   SourceRange getTargetNestedNameRange() const { return TargetNestedNameRange; }
 
-  /// \brief Set the source range coverting the nested-name-specifier preceding
-  /// the namespace name.
-  void setTargetNestedNameRange(SourceRange R) { TargetNestedNameRange = R; }
-
   /// \brief Get target nested name declaration.
   NestedNameSpecifier* getTargetNestedNameSpecifier() {
     return TargetNestedNameSpecifier;
   }
 
-  /// \brief Set the nested name declaration.
-  void setTargetNestedNameSpecifier(NestedNameSpecifier* NNS) {
-    TargetNestedNameSpecifier = NNS;
-  }
-
   /// \brief Returns the source location of the 'using' keyword.
   SourceLocation getUsingLoc() const { return UsingLocation; }
 
-  /// \brief Set the source location of the 'using' keyword.
-  void setUsingLoc(SourceLocation L) { UsingLocation = L; }
-
   /// \brief Returns the source location of the 'typename' keyword.
   SourceLocation getTypenameLoc() const { return TypenameLocation; }
 
-  /// \brief Set the source location of the 'typename' keyword.
-  void setTypenameLoc(SourceLocation L) { TypenameLocation = L; }
-
   static UnresolvedUsingTypenameDecl *
     Create(ASTContext &C, DeclContext *DC, SourceLocation UsingLoc,
            SourceLocation TypenameLoc,
            SourceRange TargetNNR, NestedNameSpecifier *TargetNNS,
            SourceLocation TargetNameLoc, DeclarationName TargetName);
 
+  SourceRange getSourceRange() const {
+    return SourceRange(UsingLocation, getLocation());
+  }
+  
   static bool classof(const Decl *D) { return classofKind(D->getKind()); }
   static bool classof(const UnresolvedUsingTypenameDecl *D) { return true; }
   static bool classofKind(Kind K) { return K == UnresolvedUsingTypename; }
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index cb6f29a0770..7adbe1220ff 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -695,10 +695,10 @@ void ASTDeclReader::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
 void ASTDeclReader::VisitUnresolvedUsingTypenameDecl(
                                                UnresolvedUsingTypenameDecl *D) {
   VisitTypeDecl(D);
-  D->setTargetNestedNameRange(Reader.ReadSourceRange(Record, Idx));
-  D->setUsingLoc(Reader.ReadSourceLocation(Record, Idx));
-  D->setTypenameLoc(Reader.ReadSourceLocation(Record, Idx));
-  D->setTargetNestedNameSpecifier(Reader.ReadNestedNameSpecifier(Record, Idx));
+  D->TargetNestedNameRange = Reader.ReadSourceRange(Record, Idx);
+  D->UsingLocation = Reader.ReadSourceLocation(Record, Idx);
+  D->TypenameLocation = Reader.ReadSourceLocation(Record, Idx);
+  D->TargetNestedNameSpecifier = Reader.ReadNestedNameSpecifier(Record, Idx);
 }
 
 void ASTDeclReader::VisitCXXRecordDecl(CXXRecordDecl *D) {
diff --git a/clang/test/Index/index-templates.cpp b/clang/test/Index/index-templates.cpp
index 9b860180091..09512630f1e 100644
--- a/clang/test/Index/index-templates.cpp
+++ b/clang/test/Index/index-templates.cpp
@@ -24,6 +24,14 @@ class vector<Z2> {
   void clear();
 };
 
+template<typename T, typename U>
+struct Y {
+  using typename T::type;
+  using U::operator Z2;
+};
+
+struct Z3 { };
+
 // RUN: c-index-test -test-load-source all %s | FileCheck -check-prefix=CHECK-LOAD %s
 // CHECK-LOAD: index-templates.cpp:4:6: FunctionTemplate=f:4:6 Extent=[3:1 - 4:22]
 // CHECK-LOAD: index-templates.cpp:3:19: TemplateTypeParameter=T:3:19 (Definition) Extent=[3:19 - 3:20]
@@ -50,6 +58,12 @@ class vector<Z2> {
 // CHECK-LOAD: index-templates.cpp:23:7: ClassDecl=vector:23:7 (Definition) Extent=[22:1 - 25:2]
 // CHECK-LOAD: index-templates.cpp:23:14: TypeRef=struct Z2:20:8 Extent=[23:14 - 23:16]
 // CHECK-LOAD: index-templates.cpp:24:8: CXXMethod=clear:24:8 Extent=[24:8 - 24:15]
+// CHECK-LOAD: index-templates.cpp:28:8: ClassTemplate=Y:28:8 (Definition) Extent=[27:1 - 31:2]
+// CHECK-LOAD: index-templates.cpp:27:19: TemplateTypeParameter=T:27:19 (Definition) Extent=[27:19 - 27:20]
+// CHECK-LOAD: index-templates.cpp:27:31: TemplateTypeParameter=U:27:31 (Definition) Extent=[27:31 - 27:32]
+// CHECK-LOAD: index-templates.cpp:29:21: UsingDeclaration=type:29:21 Extent=[29:3 - 29:25]
+// CHECK-LOAD: index-templates.cpp:30:12: UsingDeclaration=operator Z2:30:12 Extent=[30:3 - 30:23]
+// CHECK-LOAD: index-templates.cpp:30:21: TypeRef=struct Z2:20:8 Extent=[30:21 - 30:23]
 
 // RUN: c-index-test -test-load-source-usrs all %s | FileCheck -check-prefix=CHECK-USRS %s
 // CHECK-USRS: index-templates.cpp c:@FT@>3#T#Nt0.0#t>2#T#Nt1.0f#>t0.22t0.0# Extent=[3:1 - 4:22]
@@ -70,3 +84,8 @@ class vector<Z2> {
 // CHECK-USRS: index-templates.cpp c:@S@Z2 Extent=[20:1 - 20:14]
 // CHECK-USRS: index-templates.cpp c:@C@vector>#$@S@Z2#$@C@allocator>#$@S@Z2 Extent=[22:1 - 25:2]
 // CHECK-USRS: index-templates.cpp c:@C@vector>#$@S@Z2#$@C@allocator>#$@S@Z2@F@clear# Extent=[24:8 - 24:15]
+// CHECK-USRS: index-templates.cpp c:@ST>2#T#T@Y Extent=[27:1 - 31:2]
+// CHECK-USRS: index-templates.cpp c:index-templates.cpp@452 Extent=[27:19 - 27:20]
+// CHECK-USRS: index-templates.cpp c:index-templates.cpp@464 Extent=[27:31 - 27:32]
+// CHECK-USRS-NOT: type
+// CHECK-USRS: index-templates.cpp c:@S@Z3 Extent=[33:1 - 33:14]
diff --git a/clang/test/Index/load-namespaces.cpp b/clang/test/Index/load-namespaces.cpp
index 9c8db0a3a52..adb6183d171 100644
--- a/clang/test/Index/load-namespaces.cpp
+++ b/clang/test/Index/load-namespaces.cpp
@@ -15,6 +15,12 @@ namespace std0x = std98;
 
 using namespace std0x;
 
+namespace std {
+  int g(int);
+}
+
+using std::g;
+
 // 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]
@@ -27,3 +33,7 @@ using namespace std0x;
 // CHECK: load-namespaces.cpp:14:19: NamespaceRef=std98:13:11 Extent=[14:19 - 14:24]
 // CHECK: load-namespaces.cpp:16:17: UsingDirective=:16:17 Extent=[16:1 - 16:22]
 // CHECK: load-namespaces.cpp:16:17: NamespaceRef=std0x:14:11 Extent=[16:17 - 16:22]
+// CHECK: load-namespaces.cpp:18:11: Namespace=std:18:11 (Definition) Extent=[18:11 - 20:2]
+// 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]
diff --git a/clang/test/Index/usrs.cpp b/clang/test/Index/usrs.cpp
index 50d209feba1..698aded8438 100644
--- a/clang/test/Index/usrs.cpp
+++ b/clang/test/Index/usrs.cpp
@@ -61,6 +61,10 @@ using namespace foo;
 
 namespace foo_alias2 = foo;
 
+using foo::ClsB;
+
+namespace foo_alias3 = foo;
+
 // RUN: c-index-test -test-load-source-usrs all %s | FileCheck %s
 // CHECK: usrs.cpp c:@N@foo Extent=[1:11 - 4:2]
 // CHECK: usrs.cpp c:@N@foo@x Extent=[2:3 - 2:8]
@@ -116,3 +120,5 @@ namespace foo_alias2 = foo;
 // CHECK: usrs.cpp c:@NA@foo_alias
 // CHECK-NOT: foo
 // CHECK: usrs.cpp c:@NA@foo_alias2
+// CHECK-NOT: ClsB
+// CHECK: usrs.cpp c:@NA@foo_alias3
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index 3c4211efdc5..947b3b28262 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -319,6 +319,9 @@ public:
   bool VisitNamespaceDecl(NamespaceDecl *D);
   bool VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
   bool VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
+  bool VisitUsingDecl(UsingDecl *D);
+  bool VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D);
+  bool VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D);
   
   // Name visitor
   bool VisitDeclarationNameInfo(DeclarationNameInfo Name);
@@ -902,19 +905,41 @@ bool CursorVisitor::VisitNamespaceDecl(NamespaceDecl *D) {
 }
 
 bool CursorVisitor::VisitNamespaceAliasDecl(NamespaceAliasDecl *D) {
-  // FIXME: Visit nested-name-specifier
+  // FIXME: Visit nested-name-specifier.
   
   return Visit(MakeCursorNamespaceRef(D->getAliasedNamespace(), 
                                       D->getTargetNameLoc(), TU));
 }
 
+bool CursorVisitor::VisitUsingDecl(UsingDecl *D) {
+  // FIXME: Visit nested-name-specifier.
+  
+  // 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
+  // yet.
+  
+  return VisitDeclarationNameInfo(D->getNameInfo());
+}
+
 bool CursorVisitor::VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
-  // FIXME: Visit nested-name-specifier
+  // FIXME: Visit nested-name-specifier.
 
   return Visit(MakeCursorNamespaceRef(D->getNominatedNamespaceAsWritten(),
                                       D->getIdentLocation(), TU));
 }
 
+bool CursorVisitor::VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) {
+  // FIXME: Visit nested-name-specifier.
+  
+  return VisitDeclarationNameInfo(D->getNameInfo());
+}
+
+bool CursorVisitor::VisitUnresolvedUsingTypenameDecl(
+                                               UnresolvedUsingTypenameDecl *D) {
+  // FIXME: Visit nested-name-specifier.
+  return false;
+}
+
 bool CursorVisitor::VisitDeclarationNameInfo(DeclarationNameInfo Name) {
   switch (Name.getName().getNameKind()) {
   case clang::DeclarationName::Identifier:
@@ -2268,6 +2293,8 @@ CXString clang_getCursorKindSpelling(enum CXCursorKind Kind) {
     return createCXString("NamespaceAlias");
   case CXCursor_UsingDirective:
     return createCXString("UsingDirective");
+  case CXCursor_UsingDeclaration:
+    return createCXString("UsingDeclaration");
   }
 
   llvm_unreachable("Unhandled CXCursorKind");
diff --git a/clang/tools/libclang/CIndexUSRs.cpp b/clang/tools/libclang/CIndexUSRs.cpp
index a60d1d3e189..8f3dacfad21 100644
--- a/clang/tools/libclang/CIndexUSRs.cpp
+++ b/clang/tools/libclang/CIndexUSRs.cpp
@@ -86,6 +86,15 @@ public:
   void VisitUsingDirectiveDecl(UsingDirectiveDecl *D) {
     IgnoreResults = true;
   }
+  void VisitUsingDecl(UsingDecl *D) { 
+    IgnoreResults = true;
+  }
+  void VisitUnresolvedUsingValueDecl(UnresolvedUsingValueDecl *D) { 
+    IgnoreResults = true;
+  }
+  void VisitUnresolvedUsingTypenameDecl(UnresolvedUsingTypenameDecl *D) { 
+    IgnoreResults = true;
+  }
   
   /// Generate the string component containing the location of the
   ///  declaration.
diff --git a/clang/tools/libclang/CXCursor.cpp b/clang/tools/libclang/CXCursor.cpp
index 75806ffa8d7..506033e7663 100644
--- a/clang/tools/libclang/CXCursor.cpp
+++ b/clang/tools/libclang/CXCursor.cpp
@@ -71,6 +71,11 @@ static CXCursorKind GetCursorKind(Decl *D) {
       return CXCursor_ClassTemplatePartialSpecialization;
     case Decl::UsingDirective:     return CXCursor_UsingDirective;
       
+    case Decl::Using:
+    case Decl::UnresolvedUsingValue:
+    case Decl::UnresolvedUsingTypename: 
+      return CXCursor_UsingDeclaration;
+      
     default:
       if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
         switch (TD->getTagKind()) {