From: Peter Collingbourne <peter@pcc.me.uk>
Date: Sat, 23 Nov 2013 01:40:07 +0000 (+0000)
Subject: Add Distance parameter to ASTNodeKind::isBaseOf.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e6d601f912ea8fb367204f342f799196782195dd;p=clang

Add Distance parameter to ASTNodeKind::isBaseOf.

This will allow the completer to order results by relevance.

Differential Revision: http://llvm-reviews.chandlerc.com/D2209

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@195540 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/AST/ASTTypeTraits.h b/include/clang/AST/ASTTypeTraits.h
index 087ad56090..f826436c6d 100644
--- a/include/clang/AST/ASTTypeTraits.h
+++ b/include/clang/AST/ASTTypeTraits.h
@@ -57,7 +57,9 @@ public:
   bool isSame(ASTNodeKind Other) const;
 
   /// \brief Returns \c true if \c this is a base kind of (or same as) \c Other.
-  bool isBaseOf(ASTNodeKind Other) const;
+  /// \param Distance If non-null, used to return the distance between \c this
+  /// and \c Other in the class hierarchy.
+  bool isBaseOf(ASTNodeKind Other, unsigned *Distance = 0) const;
 
   /// \brief String representation of the kind.
   StringRef asStringRef() const;
@@ -91,7 +93,9 @@ private:
 
   /// \brief Returns \c true if \c Base is a base kind of (or same as) \c
   ///   Derived.
-  static bool isBaseOf(NodeKindId Base, NodeKindId Derived);
+  /// \param Distance If non-null, used to return the distance between \c Base
+  /// and \c Derived in the class hierarchy.
+  static bool isBaseOf(NodeKindId Base, NodeKindId Derived, unsigned *Distance);
 
   /// \brief Helper meta-function to convert a kind T to its enum value.
   ///
diff --git a/lib/AST/ASTTypeTraits.cpp b/lib/AST/ASTTypeTraits.cpp
index ae47ea9888..02d82d819e 100644
--- a/lib/AST/ASTTypeTraits.cpp
+++ b/lib/AST/ASTTypeTraits.cpp
@@ -39,18 +39,24 @@ const ASTNodeKind::KindInfo ASTNodeKind::AllKindInfo[] = {
 #include "clang/AST/TypeNodes.def"
 };
 
-bool ASTNodeKind::isBaseOf(ASTNodeKind Other) const {
-  return isBaseOf(KindId, Other.KindId);
+bool ASTNodeKind::isBaseOf(ASTNodeKind Other, unsigned *Distance) const {
+  return isBaseOf(KindId, Other.KindId, Distance);
 }
 
 bool ASTNodeKind::isSame(ASTNodeKind Other) const {
   return KindId != NKI_None && KindId == Other.KindId;
 }
 
-bool ASTNodeKind::isBaseOf(NodeKindId Base, NodeKindId Derived) {
+bool ASTNodeKind::isBaseOf(NodeKindId Base, NodeKindId Derived,
+                           unsigned *Distance) {
   if (Base == NKI_None || Derived == NKI_None) return false;
-  while (Derived != Base && Derived != NKI_None)
+  unsigned Dist = 0;
+  while (Derived != Base && Derived != NKI_None) {
     Derived = AllKindInfo[Derived].ParentId;
+    ++Dist;
+  }
+  if (Distance)
+    *Distance = Dist;
   return Derived == Base;
 }
 
diff --git a/unittests/AST/ASTTypeTraitsTest.cpp b/unittests/AST/ASTTypeTraitsTest.cpp
index dd73b52206..634577c5e8 100644
--- a/unittests/AST/ASTTypeTraitsTest.cpp
+++ b/unittests/AST/ASTTypeTraitsTest.cpp
@@ -34,6 +34,19 @@ TEST(ASTNodeKind, Bases) {
   EXPECT_TRUE(DNT<Decl>().isSame(DNT<Decl>()));
 }
 
+TEST(ASTNodeKind, BaseDistances) {
+  unsigned Distance = 1;
+  EXPECT_TRUE(DNT<Expr>().isBaseOf(DNT<Expr>(), &Distance));
+  EXPECT_EQ(0u, Distance);
+
+  EXPECT_TRUE(DNT<Stmt>().isBaseOf(DNT<IfStmt>(), &Distance));
+  EXPECT_EQ(1u, Distance);
+
+  Distance = 3;
+  EXPECT_TRUE(DNT<DeclaratorDecl>().isBaseOf(DNT<ParmVarDecl>(), &Distance));
+  EXPECT_EQ(2u, Distance);
+}
+
 TEST(ASTNodeKind, SameBase) {
   EXPECT_TRUE(DNT<Expr>().isBaseOf(DNT<CallExpr>()));
   EXPECT_TRUE(DNT<Expr>().isBaseOf(DNT<BinaryOperator>()));