void DeleteNullPointerCheck::registerMatchers(MatchFinder *Finder) {
  const auto DeleteExpr =
      cxxDeleteExpr(has(castExpr(has(declRefExpr(
                        to(decl(equalsBoundNode("deletedPointer"))))))))
          .bind("deleteExpr");

  const auto DeleteMemberExpr =
      cxxDeleteExpr(has(castExpr(has(memberExpr(hasDeclaration(
                        fieldDecl(equalsBoundNode("deletedMemberPointer"))))))))
          .bind("deleteMemberExpr");

  const auto PointerExpr = ignoringImpCasts(anyOf(
      declRefExpr(to(decl().bind("deletedPointer"))),
      memberExpr(hasDeclaration(fieldDecl().bind("deletedMemberPointer")))));

  const auto PointerCondition = castExpr(hasCastKind(CK_PointerToBoolean),
                                         hasSourceExpression(PointerExpr));
  const auto BinaryPointerCheckCondition =
      binaryOperator(hasEitherOperand(castExpr(hasCastKind(CK_NullToPointer))),
                     hasEitherOperand(PointerExpr));

  Finder->addMatcher(
      ifStmt(hasCondition(anyOf(PointerCondition, BinaryPointerCheckCondition)),
             hasThen(anyOf(
                 DeleteExpr, DeleteMemberExpr,
                 compoundStmt(anyOf(has(DeleteExpr), has(DeleteMemberExpr)),
                              statementCountIs(1))
                     .bind("compound"))))
          .bind("ifWithDelete"),
      this);
}
void UseEmplaceCheck::registerMatchers(MatchFinder *Finder) {
  if (!getLangOpts().CPlusPlus11)
    return;

  // FIXME: Bunch of functionality that could be easily added:
  // + add handling of `push_front` for std::forward_list, std::list
  // and std::deque.
  // + add handling of `push` for std::stack, std::queue, std::priority_queue
  // + add handling of `insert` for stl associative container, but be careful
  // because this requires special treatment (it could cause performance
  // regression)
  // + match for emplace calls that should be replaced with insertion
  // + match for make_pair calls.
  auto callPushBack = cxxMemberCallExpr(
      hasDeclaration(functionDecl(hasName("push_back"))),
      on(hasType(cxxRecordDecl(hasAnyName("std::vector", "llvm::SmallVector",
                                          "std::list", "std::deque")))));

  // We can't replace push_backs of smart pointer because
  // if emplacement fails (f.e. bad_alloc in vector) we will have leak of
  // passed pointer because smart pointer won't be constructed
  // (and destructed) as in push_back case.
  auto isCtorOfSmartPtr = hasDeclaration(cxxConstructorDecl(
      ofClass(hasAnyName("std::shared_ptr", "std::unique_ptr", "std::auto_ptr",
                         "std::weak_ptr"))));

  // Bitfields binds only to consts and emplace_back take it by universal ref.
  auto bitFieldAsArgument = hasAnyArgument(ignoringParenImpCasts(
      memberExpr(hasDeclaration(fieldDecl(matchers::isBitfield())))));

  // We could have leak of resource.
  auto newExprAsArgument = hasAnyArgument(ignoringParenImpCasts(cxxNewExpr()));
  auto constructingDerived =
      hasParent(implicitCastExpr(hasCastKind(CastKind::CK_DerivedToBase)));

  auto hasInitList = has(ignoringParenImpCasts(initListExpr()));
  auto soughtConstructExpr =
      cxxConstructExpr(
          unless(anyOf(isCtorOfSmartPtr, hasInitList, bitFieldAsArgument,
                       newExprAsArgument, constructingDerived,
                       has(materializeTemporaryExpr(hasInitList)))))
          .bind("ctor");
  auto hasConstructExpr = has(ignoringParenImpCasts(soughtConstructExpr));

  auto ctorAsArgument = materializeTemporaryExpr(
      anyOf(hasConstructExpr, has(cxxFunctionalCastExpr(hasConstructExpr))));

  Finder->addMatcher(
      cxxMemberCallExpr(callPushBack, has(ctorAsArgument)).bind("call"), this);
}
void UseEmplaceCheck::registerMatchers(MatchFinder *Finder) {
  if (!getLangOpts().CPlusPlus11)
    return;

  // FIXME: Bunch of functionality that could be easily added:
  // + add handling of `push_front` for std::forward_list, std::list
  // and std::deque.
  // + add handling of `push` for std::stack, std::queue, std::priority_queue
  // + add handling of `insert` for stl associative container, but be careful
  // because this requires special treatment (it could cause performance
  // regression)
  // + match for emplace calls that should be replaced with insertion
  // + match for make_pair calls.
  auto callPushBack = cxxMemberCallExpr(
      hasDeclaration(functionDecl(hasName("push_back"))),
      on(hasType(cxxRecordDecl(hasAnyName(SmallVector<StringRef, 5>(
          ContainersWithPushBack.begin(), ContainersWithPushBack.end()))))));

  // We can't replace push_backs of smart pointer because
  // if emplacement fails (f.e. bad_alloc in vector) we will have leak of
  // passed pointer because smart pointer won't be constructed
  // (and destructed) as in push_back case.
  auto isCtorOfSmartPtr = hasDeclaration(cxxConstructorDecl(ofClass(hasAnyName(
      SmallVector<StringRef, 5>(SmartPointers.begin(), SmartPointers.end())))));

  // Bitfields binds only to consts and emplace_back take it by universal ref.
  auto bitFieldAsArgument = hasAnyArgument(
      ignoringImplicit(memberExpr(hasDeclaration(fieldDecl(isBitField())))));

  // Initializer list can't be passed to universal reference.
  auto initializerListAsArgument = hasAnyArgument(
      ignoringImplicit(cxxConstructExpr(isListInitialization())));

  // We could have leak of resource.
  auto newExprAsArgument = hasAnyArgument(ignoringImplicit(cxxNewExpr()));
  // We would call another constructor.
  auto constructingDerived =
      hasParent(implicitCastExpr(hasCastKind(CastKind::CK_DerivedToBase)));

  // emplace_back can't access private constructor.
  auto isPrivateCtor = hasDeclaration(cxxConstructorDecl(isPrivate()));

  auto hasInitList = has(ignoringImplicit(initListExpr()));
  // FIXME: Discard 0/NULL (as nullptr), static inline const data members,
  // overloaded functions and template names.
  auto soughtConstructExpr =
      cxxConstructExpr(
          unless(anyOf(isCtorOfSmartPtr, hasInitList, bitFieldAsArgument,
                       initializerListAsArgument, newExprAsArgument,
                       constructingDerived, isPrivateCtor)))
          .bind("ctor");
  auto hasConstructExpr = has(ignoringImplicit(soughtConstructExpr));

  auto ctorAsArgument = materializeTemporaryExpr(
      anyOf(hasConstructExpr, has(cxxFunctionalCastExpr(hasConstructExpr))));

  Finder->addMatcher(cxxMemberCallExpr(callPushBack, has(ctorAsArgument),
                                       unless(isInTemplateInstantiation()))
                         .bind("call"),
                     this);
}
void UpgradeDurationConversionsCheck::registerMatchers(MatchFinder *Finder) {
  if (!getLangOpts().CPlusPlus)
    return;

  // For the arithmetic calls, we match only the uses of the templated operators
  // where the template parameter is not a built-in type. This means the
  // instantiation makes use of an available user defined conversion to
  // `int64_t`.
  //
  // The implementation of these templates will be updated to fail SFINAE for
  // non-integral types. We match them to suggest an explicit cast.

  // Match expressions like `a *= b` and `a /= b` where `a` has type
  // `absl::Duration` and `b` is not of a built-in type.
  Finder->addMatcher(
      cxxOperatorCallExpr(
          argumentCountIs(2),
          hasArgument(
              0, expr(hasType(cxxRecordDecl(hasName("::absl::Duration"))))),
          hasArgument(1, expr().bind("arg")),
          callee(functionDecl(
              hasParent(functionTemplateDecl()),
              unless(hasTemplateArgument(0, refersToType(builtinType()))),
              hasAnyName("operator*=", "operator/=")))),
      this);

  // Match expressions like `a.operator*=(b)` and `a.operator/=(b)` where `a`
  // has type `absl::Duration` and `b` is not of a built-in type.
  Finder->addMatcher(
      cxxMemberCallExpr(
          callee(cxxMethodDecl(
              ofClass(cxxRecordDecl(hasName("::absl::Duration"))),
              hasParent(functionTemplateDecl()),
              unless(hasTemplateArgument(0, refersToType(builtinType()))),
              hasAnyName("operator*=", "operator/="))),
          argumentCountIs(1), hasArgument(0, expr().bind("arg"))),
      this);

  // Match expressions like `a * b`, `a / b`, `operator*(a, b)`, and
  // `operator/(a, b)` where `a` has type `absl::Duration` and `b` is not of a
  // built-in type.
  Finder->addMatcher(
      callExpr(callee(functionDecl(
                   hasParent(functionTemplateDecl()),
                   unless(hasTemplateArgument(0, refersToType(builtinType()))),
                   hasAnyName("::absl::operator*", "::absl::operator/"))),
               argumentCountIs(2),
               hasArgument(0, expr(hasType(
                                  cxxRecordDecl(hasName("::absl::Duration"))))),
               hasArgument(1, expr().bind("arg"))),
      this);

  // Match expressions like `a * b` and `operator*(a, b)` where `a` is not of a
  // built-in type and `b` has type `absl::Duration`.
  Finder->addMatcher(
      callExpr(callee(functionDecl(
                   hasParent(functionTemplateDecl()),
                   unless(hasTemplateArgument(0, refersToType(builtinType()))),
                   hasName("::absl::operator*"))),
               argumentCountIs(2), hasArgument(0, expr().bind("arg")),
               hasArgument(1, expr(hasType(cxxRecordDecl(
                                  hasName("::absl::Duration")))))),
      this);

  // For the factory functions, we match only the non-templated overloads that
  // take an `int64_t` parameter. Within these calls, we care about implicit
  // casts through a user defined conversion to `int64_t`.
  //
  // The factory functions will be updated to be templated and SFINAE on whether
  // the template parameter is an integral type. This complements the already
  // existing templated overloads that only accept floating point types.

  // Match calls like:
  //   `absl::Nanoseconds(x)`
  //   `absl::Microseconds(x)`
  //   `absl::Milliseconds(x)`
  //   `absl::Seconds(x)`
  //   `absl::Minutes(x)`
  //   `absl::Hours(x)`
  // where `x` is not of a built-in type.
  Finder->addMatcher(
      implicitCastExpr(
          anyOf(hasCastKind(CK_UserDefinedConversion),
                has(implicitCastExpr(hasCastKind(CK_UserDefinedConversion)))),
          hasParent(callExpr(
              callee(functionDecl(DurationFactoryFunction(),
                  unless(hasParent(functionTemplateDecl())))),
              hasArgument(0, expr().bind("arg"))))),
      this);
}