void InaccurateEraseCheck::registerMatchers(MatchFinder *Finder) {
  // Only register the matchers for C++; the functionality currently does not
  // provide any benefit to other languages, despite being benign.
  if (!getLangOpts().CPlusPlus)
    return;

  const auto EndCall =
      callExpr(
          callee(functionDecl(hasAnyName("remove", "remove_if", "unique"))),
          hasArgument(
              1,
              anyOf(cxxConstructExpr(has(ignoringImplicit(
                        cxxMemberCallExpr(callee(cxxMethodDecl(hasName("end"))))
                            .bind("end")))),
                    anything())))
          .bind("alg");

  const auto DeclInStd = type(hasUnqualifiedDesugaredType(
      tagType(hasDeclaration(decl(isInStdNamespace())))));
  Finder->addMatcher(
      cxxMemberCallExpr(
          on(anyOf(hasType(DeclInStd), hasType(pointsTo(DeclInStd)))),
          callee(cxxMethodDecl(hasName("erase"))), argumentCountIs(1),
          hasArgument(0, has(ignoringImplicit(
                             anyOf(EndCall, has(ignoringImplicit(EndCall)))))),
          unless(isInTemplateInstantiation()))
          .bind("erase"),
      this);
}
void InaccurateEraseCheck::registerMatchers(MatchFinder *Finder) {
  // Only register the matchers for C++; the functionality currently does not
  // provide any benefit to other languages, despite being benign.
  if (!getLangOpts().CPlusPlus)
    return;

  const auto CheckForEndCall = hasArgument(
      1, anyOf(cxxConstructExpr(has(ignoringParenImpCasts(
                   cxxMemberCallExpr(callee(cxxMethodDecl(hasName("end"))))
                       .bind("InaccEndCall")))),
               anything()));

  Finder->addMatcher(
      cxxMemberCallExpr(
          on(hasType(namedDecl(matchesName("^::std::")))),
          callee(cxxMethodDecl(hasName("erase"))), argumentCountIs(1),
          hasArgument(0, has(ignoringParenImpCasts(
                             callExpr(callee(functionDecl(matchesName(
                                          "^::std::(remove(_if)?|unique)$"))),
                                      CheckForEndCall)
                                 .bind("InaccAlgCall")))),
          unless(isInTemplateInstantiation()))
          .bind("InaccErase"),
      this);
}
void MakeSmartPtrCheck::registerMatchers(ast_matchers::MatchFinder *Finder) {
  if (!isLanguageVersionSupported(getLangOpts()))
    return;

  // Calling make_smart_ptr from within a member function of a type with a
  // private or protected constructor would be ill-formed.
  auto CanCallCtor = unless(has(ignoringImpCasts(
      cxxConstructExpr(hasDeclaration(decl(unless(isPublic())))))));

  Finder->addMatcher(
      cxxBindTemporaryExpr(has(ignoringParenImpCasts(
          cxxConstructExpr(
              hasType(getSmartPointerTypeMatcher()), argumentCountIs(1),
              hasArgument(0,
                          cxxNewExpr(hasType(pointsTo(qualType(hasCanonicalType(
                                         equalsBoundNode(PointerType))))),
                                     CanCallCtor)
                              .bind(NewExpression)),
              unless(isInTemplateInstantiation()))
              .bind(ConstructorCall)))),
      this);

  Finder->addMatcher(
      cxxMemberCallExpr(
          thisPointerType(getSmartPointerTypeMatcher()),
          callee(cxxMethodDecl(hasName("reset"))),
          hasArgument(0, cxxNewExpr(CanCallCtor).bind(NewExpression)),
          unless(isInTemplateInstantiation()))
          .bind(ResetCall),
      this);
}
void ShrinkToFitCheck::registerMatchers(MatchFinder *Finder) {
  // Swap as a function need not to be considered, because rvalue can not
  // be bound to a non-const reference.
  const auto ShrinkableAsMember =
      memberExpr(member(valueDecl().bind("ContainerDecl")));
  const auto ShrinkableAsDecl =
      declRefExpr(hasDeclaration(valueDecl().bind("ContainerDecl")));
  const auto CopyCtorCall = cxxConstructExpr(
      hasArgument(0, anyOf(ShrinkableAsMember, ShrinkableAsDecl,
                           unaryOperator(has(ShrinkableAsMember)),
                           unaryOperator(has(ShrinkableAsDecl)))));
  const auto SwapParam = expr(anyOf(
      memberExpr(member(equalsBoundNode("ContainerDecl"))),
      declRefExpr(hasDeclaration(equalsBoundNode("ContainerDecl"))),
      unaryOperator(has(memberExpr(member(equalsBoundNode("ContainerDecl"))))),
      unaryOperator(
          has(declRefExpr(hasDeclaration(equalsBoundNode("ContainerDecl")))))));

  Finder->addMatcher(
      cxxMemberCallExpr(on(hasType(namedDecl(stlShrinkableContainer()))),
                        callee(cxxMethodDecl(hasName("swap"))),
                        has(memberExpr(hasDescendant(CopyCtorCall))),
                        hasArgument(0, SwapParam.bind("ContainerToShrink")),
                        unless(isInTemplateInstantiation()))
          .bind("CopyAndSwapTrick"),
      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 FasterStringFindCheck::registerMatchers(MatchFinder *Finder) {
  if (!getLangOpts().CPlusPlus)
    return;

  const auto SingleChar =
      expr(ignoringParenCasts(stringLiteral(hasSize(1)).bind("literal")));

  const auto StringFindFunctions =
      anyOf(hasName("find"), hasName("rfind"), hasName("find_first_of"),
            hasName("find_first_not_of"), hasName("find_last_of"),
            hasName("find_last_not_of"));

  llvm::Optional<ast_matchers::internal::Matcher<NamedDecl>> IsStringClass;

  for (const auto &ClassName : StringLikeClasses) {
    const auto HasName = hasName(ClassName);
    IsStringClass = IsStringClass ? anyOf(*IsStringClass, HasName) : HasName;
  }

  if (IsStringClass) {
    Finder->addMatcher(
        cxxMemberCallExpr(
            callee(functionDecl(StringFindFunctions).bind("func")),
            anyOf(argumentCountIs(1), argumentCountIs(2)),
            hasArgument(0, SingleChar),
            on(expr(hasType(recordDecl(*IsStringClass)),
                    unless(hasSubstitutedType())))),
        this);
  }
}
void ParentVirtualCallCheck::registerMatchers(MatchFinder *Finder) {
  Finder->addMatcher(
      cxxMemberCallExpr(
          callee(memberExpr(hasDescendant(implicitCastExpr(
                                hasImplicitDestinationType(pointsTo(
                                    type(anything()).bind("castToType"))),
                                hasSourceExpression(cxxThisExpr(hasType(
                                    type(anything()).bind("thisType")))))))
                     .bind("member")),
          callee(cxxMethodDecl(isVirtual()))),
      this);
}
void UniqueptrResetReleaseCheck::registerMatchers(MatchFinder *Finder) {
  // Only register the matchers for C++11; the functionality currently does not
  // provide any benefit to other languages, despite being benign.
  if (!getLangOpts().CPlusPlus11)
    return;

  Finder->addMatcher(
      cxxMemberCallExpr(
          on(expr().bind("left")), callee(memberExpr().bind("reset_member")),
          callee(
              cxxMethodDecl(hasName("reset"),
                            ofClass(cxxRecordDecl(hasName("::std::unique_ptr"),
                                                  decl().bind("left_class"))))),
          has(ignoringParenImpCasts(cxxMemberCallExpr(
              on(expr().bind("right")),
              callee(memberExpr().bind("release_member")),
              callee(cxxMethodDecl(
                  hasName("release"),
                  ofClass(cxxRecordDecl(hasName("::std::unique_ptr"),
                                        decl().bind("right_class")))))))))
          .bind("reset_call"),
      this);
}
void UniqueptrDeleteReleaseCheck::registerMatchers(MatchFinder *Finder) {
  auto IsSusbstituted = qualType(anyOf(
      substTemplateTypeParmType(), hasDescendant(substTemplateTypeParmType())));

  auto UniquePtrWithDefaultDelete = classTemplateSpecializationDecl(
      hasName("std::unique_ptr"),
      hasTemplateArgument(1, refersToType(qualType(hasDeclaration(cxxRecordDecl(
                                 hasName("std::default_delete")))))));

  Finder->addMatcher(
      cxxDeleteExpr(has(ignoringParenImpCasts(cxxMemberCallExpr(
                        on(expr(hasType(UniquePtrWithDefaultDelete),
                                unless(hasType(IsSusbstituted)))
                               .bind("uptr")),
                        callee(cxxMethodDecl(hasName("release")))))))
          .bind("delete"),
      this);
}
void ProperlySeededRandomGeneratorCheck::registerMatchers(MatchFinder *Finder) {
  auto RandomGeneratorEngineDecl = cxxRecordDecl(hasAnyName(
      "::std::linear_congruential_engine", "::std::mersenne_twister_engine",
      "::std::subtract_with_carry_engine", "::std::discard_block_engine",
      "::std::independent_bits_engine", "::std::shuffle_order_engine"));
  auto RandomGeneratorEngineTypeMatcher = hasType(hasUnqualifiedDesugaredType(
      recordType(hasDeclaration(RandomGeneratorEngineDecl))));

  // std::mt19937 engine;
  // engine.seed();
  //        ^
  // engine.seed(1);
  //        ^
  // const int x = 1;
  // engine.seed(x);
  //        ^
  Finder->addMatcher(
      cxxMemberCallExpr(
          has(memberExpr(has(declRefExpr(RandomGeneratorEngineTypeMatcher)),
                         member(hasName("seed")),
                         unless(hasDescendant(cxxThisExpr())))))
          .bind("seed"),
      this);

  // std::mt19937 engine;
  //              ^
  // std::mt19937 engine(1);
  //              ^
  // const int x = 1;
  // std::mt19937 engine(x);
  //              ^
  Finder->addMatcher(
      cxxConstructExpr(RandomGeneratorEngineTypeMatcher).bind("ctor"), this);

  // srand();
  // ^
  // const int x = 1;
  // srand(x);
  // ^
  Finder->addMatcher(
      callExpr(callee(functionDecl(hasAnyName("::srand", "::std::srand"))))
          .bind("srand"),
      this);
}
void FasterStringFindCheck::registerMatchers(MatchFinder *Finder) {
  if (!getLangOpts().CPlusPlus)
    return;

  const auto SingleChar =
      expr(ignoringParenCasts(stringLiteral(hasSize(1)).bind("literal")));
  const auto StringFindFunctions =
      hasAnyName("find", "rfind", "find_first_of", "find_first_not_of",
                 "find_last_of", "find_last_not_of");

  Finder->addMatcher(
      cxxMemberCallExpr(
          callee(functionDecl(StringFindFunctions).bind("func")),
          anyOf(argumentCountIs(1), argumentCountIs(2)),
          hasArgument(0, SingleChar),
          on(expr(
              hasType(hasUnqualifiedDesugaredType(recordType(hasDeclaration(
                  recordDecl(hasAnyName(SmallVector<StringRef, 4>(
                      StringLikeClasses.begin(), StringLikeClasses.end()))))))),
              unless(hasSubstitutedType())))),
      this);
}
void ContainerSizeEmptyCheck::registerMatchers(MatchFinder *Finder) {
  // Only register the matchers for C++; the functionality currently does not
  // provide any benefit to other languages, despite being benign.
  if (!getLangOpts().CPlusPlus)
    return;

  const auto ValidContainer = cxxRecordDecl(isSameOrDerivedFrom(
      namedDecl(
          has(cxxMethodDecl(
                  isConst(), parameterCountIs(0), isPublic(), hasName("size"),
                  returns(qualType(isInteger(), unless(booleanType()))))
                  .bind("size")),
          has(cxxMethodDecl(isConst(), parameterCountIs(0), isPublic(),
                            hasName("empty"), returns(booleanType()))
                  .bind("empty")))
          .bind("container")));

  const auto WrongUse = anyOf(
      hasParent(binaryOperator(
                    matchers::isComparisonOperator(),
                    hasEitherOperand(ignoringImpCasts(anyOf(
                        integerLiteral(equals(1)), integerLiteral(equals(0))))))
                    .bind("SizeBinaryOp")),
      hasParent(implicitCastExpr(
          hasImplicitDestinationType(booleanType()),
          anyOf(
              hasParent(unaryOperator(hasOperatorName("!")).bind("NegOnSize")),
              anything()))),
      hasParent(explicitCastExpr(hasDestinationType(booleanType()))));

  Finder->addMatcher(
      cxxMemberCallExpr(on(expr(anyOf(hasType(ValidContainer),
                                      hasType(pointsTo(ValidContainer)),
                                      hasType(references(ValidContainer))))
                               .bind("STLObject")),
                        callee(cxxMethodDecl(hasName("size"))), WrongUse)
          .bind("SizeCallExpr"),
      this);
}
Пример #13
0
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);
}
Пример #14
0
void CanRunScriptChecker::registerMatchers(MatchFinder *AstMatcher) {
  auto InvalidArg =
      // We want to find any expression,
      ignoreTrivials(expr(
          // which has a refcounted pointer type,
          hasType(pointerType(
              pointee(hasDeclaration(cxxRecordDecl(isRefCounted()))))),
          // and which is not this,
          unless(cxxThisExpr()),
          // and which is not a method call on a smart ptr,
          unless(cxxMemberCallExpr(on(hasType(isSmartPtrToRefCounted())))),
          // and which is not a parameter of the parent function,
          unless(declRefExpr(to(parmVarDecl()))),
          // and which is not a MOZ_KnownLive wrapped value.
          unless(callExpr(callee(functionDecl(hasName("MOZ_KnownLive"))))),
          expr().bind("invalidArg")));

  auto OptionalInvalidExplicitArg = anyOf(
      // We want to find any argument which is invalid.
      hasAnyArgument(InvalidArg),

      // This makes this matcher optional.
      anything());

  // Please not that the hasCanRunScriptAnnotation() matchers are not present
  // directly in the cxxMemberCallExpr, callExpr and constructExpr matchers
  // because we check that the corresponding functions can run script later in
  // the checker code.
  AstMatcher->addMatcher(
      expr(
          anyOf(
              // We want to match a method call expression,
              cxxMemberCallExpr(
                  // which optionally has an invalid arg,
                  OptionalInvalidExplicitArg,
                  // or which optionally has an invalid implicit this argument,
                  anyOf(
                      // which derefs into an invalid arg,
                      on(cxxOperatorCallExpr(
                          anyOf(hasAnyArgument(InvalidArg), anything()))),
                      // or is an invalid arg.
                      on(InvalidArg),

                      anything()),
                  expr().bind("callExpr")),
              // or a regular call expression,
              callExpr(
                  // which optionally has an invalid arg.
                  OptionalInvalidExplicitArg, expr().bind("callExpr")),
              // or a construct expression,
              cxxConstructExpr(
                  // which optionally has an invalid arg.
                  OptionalInvalidExplicitArg, expr().bind("constructExpr"))),

          anyOf(
              // We want to match the parent function.
              forFunction(functionDecl().bind("nonCanRunScriptParentFunction")),

              // ... optionally.
              anything())),
      this);
}
void DanglingOnTemporaryChecker::registerMatchers(MatchFinder *AstMatcher) {
  ////////////////////////////////////////
  // Quick annotation conflict checkers //
  ////////////////////////////////////////

  AstMatcher->addMatcher(
      // This is a matcher on a method declaration,
      cxxMethodDecl(
          // which is marked as no dangling on temporaries,
          noDanglingOnTemporaries(),

          // and which is && ref-qualified.
          isRValueRefQualified(),

          decl().bind("invalidMethodRefQualified")),
      this);

  AstMatcher->addMatcher(
      // This is a matcher on a method declaration,
      cxxMethodDecl(
          // which is marked as no dangling on temporaries,
          noDanglingOnTemporaries(),

          // which returns a primitive type,
          returns(builtinType()),

          // and which doesn't return a pointer.
          unless(returns(pointerType())),

          decl().bind("invalidMethodPointer")),
      this);

  //////////////////
  // Main checker //
  //////////////////

  auto hasParentCall =
      hasParent(expr(anyOf(
          cxxOperatorCallExpr(
              // If we're in a lamda, we may have an operator call expression
              // ancestor in the AST, but the temporary we're matching
              // against is not going to have the same lifetime as the
              // constructor call.
              unless(has(expr(ignoreTrivials(lambdaExpr())))),
              expr().bind("parentOperatorCallExpr")),
          callExpr(
              // If we're in a lamda, we may have a call expression
              // ancestor in the AST, but the temporary we're matching
              // against is not going to have the same lifetime as the
              // function call.
              unless(has(expr(ignoreTrivials(lambdaExpr())))),
              expr().bind("parentCallExpr")),
          objcMessageExpr(
              // If we're in a lamda, we may have an objc message expression
              // ancestor in the AST, but the temporary we're matching
              // against is not going to have the same lifetime as the
              // function call.
              unless(has(expr(ignoreTrivials(lambdaExpr())))),
              expr().bind("parentObjCMessageExpr")),
          cxxConstructExpr(
              // If we're in a lamda, we may have a construct expression
              // ancestor in the AST, but the temporary we're matching
              // against is not going to have the same lifetime as the
              // constructor call.
              unless(has(expr(ignoreTrivials(lambdaExpr())))),
              expr().bind("parentConstructExpr")))));

  AstMatcher->addMatcher(
      // This is a matcher on a method call,
      cxxMemberCallExpr(
          // which is in first party code,
          isFirstParty(),

          // and which is performed on a temporary,
          on(allOf(
              unless(hasType(pointerType())),
              isTemporary(),
              // but which is not `this`.
              unless(cxxThisExpr()))),

          // and which is marked as no dangling on temporaries.
          callee(cxxMethodDecl(noDanglingOnTemporaries())),

          expr().bind("memberCallExpr"),

          // We optionally match a parent call expression or a parent construct
          // expression because using a temporary inside a call is fine as long
          // as the pointer doesn't escape the function call.
          anyOf(
              // This is the case where the call is the direct parent, so we
              // know that the member call expression is the argument.
              allOf(hasParentCall, expr().bind("parentCallArg")),

              // This is the case where the call is not the direct parent, so we
              // get its child to know in which argument tree we are.
              hasAncestor(expr(
                  hasParentCall,
                  expr().bind("parentCallArg"))),
              // To make it optional.
              anything())),
      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);
}