path: root/include/clang/ASTMatchers/ASTMatchersInternal.h

//===--- ASTMatchersInternal.h - Structural query framework -----*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  Implements the base layer of the matcher framework.
//
//  Matchers are methods that return a Matcher<T> which provides a method
//  Matches(...) which is a predicate on an AST node. The Matches method's
//  parameters define the context of the match, which allows matchers to recurse
//  or store the current node as bound to a specific string, so that it can be
//  retrieved later.
//
//  In general, matchers have two parts:
//  1. A function Matcher<T> MatcherName(<arguments>) which returns a Matcher<T>
//     based on the arguments and optionally on template type deduction based
//     on the arguments. Matcher<T>s form an implicit reverse hierarchy
//     to clang's AST class hierarchy, meaning that you can use a Matcher<Base>
//     everywhere a Matcher<Derived> is required.
//  2. An implementation of a class derived from MatcherInterface<T>.
//
//  The matcher functions are defined in ASTMatchers.h. To make it possible
//  to implement both the matcher function and the implementation of the matcher
//  interface in one place, ASTMatcherMacros.h defines macros that allow
//  implementing a matcher in a single place.
//
//  This file contains the base classes needed to construct the actual matchers.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_AST_MATCHERS_AST_MATCHERS_INTERNAL_H
#define LLVM_CLANG_AST_MATCHERS_AST_MATCHERS_INTERNAL_H

#include "clang/AST/ASTTypeTraits.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/Decl.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/StmtCXX.h"
#include "clang/AST/Stmt.h"
#include "clang/AST/Type.h"
#include "llvm/ADT/VariadicFunction.h"
#include "llvm/Support/type_traits.h"
#include <map>
#include <string>
#include <vector>

namespace clang {
namespace ast_matchers {

/// FIXME: Move into the llvm support library.
template <bool> struct CompileAssert {};
#define TOOLING_COMPILE_ASSERT(Expr, Msg) \
  typedef CompileAssert<(bool(Expr))> Msg[bool(Expr) ? 1 : -1]

class BoundNodes;

namespace internal {

class BoundNodesTreeBuilder;
/// \brief Internal version of BoundNodes. Holds all the bound nodes.
class BoundNodesMap {
public:
  /// \brief Adds \c Node to the map with key \c ID.
  ///
  /// The node's base type should be in NodeBaseType or it will be unaccessible.
  template <typename T>
  void addNode(StringRef ID, const T* Node) {
    NodeMap[ID] = ast_type_traits::DynTypedNode::create(*Node);
  }
  void addNode(StringRef ID, ast_type_traits::DynTypedNode Node) {
    NodeMap[ID] = Node;
  }

  /// \brief Returns the AST node bound to \c ID.
  ///
  /// Returns NULL if there was no node bound to \c ID or if there is a node but
  /// it cannot be converted to the specified type.
  template <typename T>
  const T *getNodeAs(StringRef ID) const {
    IDToNodeMap::const_iterator It = NodeMap.find(ID);
    if (It == NodeMap.end()) {
      return NULL;
    }
    return It->second.get<T>();
  }

  /// \brief Copies all ID/Node pairs to BoundNodesTreeBuilder \c Builder.
  void copyTo(BoundNodesTreeBuilder *Builder) const;

  /// \brief Copies all ID/Node pairs to BoundNodesMap \c Other.
  void copyTo(BoundNodesMap *Other) const;

private:
  /// \brief A map from IDs to the bound nodes.
  typedef std::map<std::string, ast_type_traits::DynTypedNode> IDToNodeMap;

  IDToNodeMap NodeMap;
};

/// \brief A tree of bound nodes in match results.
///
/// If a match can contain multiple matches on the same node with different
/// matching subexpressions, BoundNodesTree contains a branch for each of
/// those matching subexpressions.
///
/// BoundNodesTree's are created during the matching process; when a match
/// is found, we iterate over the tree and create a BoundNodes object containing
/// the union of all bound nodes on the path from the root to a each leaf.
class BoundNodesTree {
public:
  /// \brief A visitor interface to visit all BoundNodes results for a
  /// BoundNodesTree.
  class Visitor {
  public:
    virtual ~Visitor() {}

    /// \brief Called multiple times during a single call to VisitMatches(...).
    ///
    /// 'BoundNodesView' contains the bound nodes for a single match.
    virtual void visitMatch(const BoundNodes& BoundNodesView) = 0;
  };

  BoundNodesTree();

  /// \brief Create a BoundNodesTree from pre-filled maps of bindings.