C++ NotMatchExpression类代码示例

// static
MatchExpression* CanonicalQuery::normalizeTree(MatchExpression* root) {
    // root->isLogical() is true now.  We care about AND, OR, and NOT. NOR currently scares us.
    if (MatchExpression::AND == root->matchType() || MatchExpression::OR == root->matchType()) {
        // We could have AND of AND of AND.  Make sure we clean up our children before merging
        // them.
        // UNITTEST 11738048
        for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
            (*root->getChildVector())[i] = normalizeTree(root->getChild(i));
        }

        // If any of our children are of the same logical operator that we are, we remove the
        // child's children and append them to ourselves after we examine all children.
        std::vector<MatchExpression*> absorbedChildren;

        for (size_t i = 0; i < root->numChildren();) {
            MatchExpression* child = root->getChild(i);
            if (child->matchType() == root->matchType()) {
                // AND of an AND or OR of an OR.  Absorb child's children into ourself.
                for (size_t j = 0; j < child->numChildren(); ++j) {
                    absorbedChildren.push_back(child->getChild(j));
                }
                // TODO(opt): this is possibly n^2-ish
                root->getChildVector()->erase(root->getChildVector()->begin() + i);
                child->getChildVector()->clear();
                // Note that this only works because we cleared the child's children
                delete child;
                // Don't increment 'i' as the current child 'i' used to be child 'i+1'
            } else {
                ++i;
            }
        }

        root->getChildVector()->insert(
            root->getChildVector()->end(), absorbedChildren.begin(), absorbedChildren.end());

        // AND of 1 thing is the thing, OR of 1 thing is the thing.
        if (1 == root->numChildren()) {
            MatchExpression* ret = root->getChild(0);
            root->getChildVector()->clear();
            delete root;
            return ret;
        }
    } else if (MatchExpression::NOT == root->matchType()) {
        // Normalize the rest of the tree hanging off this NOT node.
        NotMatchExpression* nme = static_cast<NotMatchExpression*>(root);
        MatchExpression* child = nme->releaseChild();
        // normalizeTree(...) takes ownership of 'child', and then
        // transfers ownership of its return value to 'nme'.
        nme->resetChild(normalizeTree(child));
    } else if (MatchExpression::ELEM_MATCH_VALUE == root->matchType()) {
        // Just normalize our children.
        for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
            (*root->getChildVector())[i] = normalizeTree(root->getChild(i));
        }
    }

    return root;
}

TEST(NotMatchExpression, MatchesScalar) {
    BSONObj baseOperand = BSON("$lt" << 5);
    unique_ptr<ComparisonMatchExpression> lt(new LTMatchExpression());
    ASSERT(lt->init("a", baseOperand["$lt"]).isOK());
    NotMatchExpression notOp;
    ASSERT(notOp.init(lt.release()).isOK());
    ASSERT(notOp.matchesBSON(BSON("a" << 6), NULL));
    ASSERT(!notOp.matchesBSON(BSON("a" << 4), NULL));
}

// static
MatchExpression* CanonicalQuery::normalizeTree(MatchExpression* root) {
    if (MatchExpression::AND == root->matchType() || MatchExpression::OR == root->matchType()) {
        // We could have AND of AND of AND.  Make sure we clean up our children before merging them.
        for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
            (*root->getChildVector())[i] = normalizeTree(root->getChild(i));
        }

        // If any of our children are of the same logical operator that we are, we remove the
        // child's children and append them to ourselves after we examine all children.
        std::vector<MatchExpression*> absorbedChildren;

        for (size_t i = 0; i < root->numChildren();) {
            MatchExpression* child = root->getChild(i);
            if (child->matchType() == root->matchType()) {
                // AND of an AND or OR of an OR.  Absorb child's children into ourself.
                for (size_t j = 0; j < child->numChildren(); ++j) {
                    absorbedChildren.push_back(child->getChild(j));
                }
                // TODO(opt): this is possibly n^2-ish
                root->getChildVector()->erase(root->getChildVector()->begin() + i);
                child->getChildVector()->clear();
                // Note that this only works because we cleared the child's children
                delete child;
                // Don't increment 'i' as the current child 'i' used to be child 'i+1'
            } else {
                ++i;
            }
        }

        root->getChildVector()->insert(
            root->getChildVector()->end(), absorbedChildren.begin(), absorbedChildren.end());

        // AND of 1 thing is the thing, OR of 1 thing is the thing.
        if (1 == root->numChildren()) {
            MatchExpression* ret = root->getChild(0);
            root->getChildVector()->clear();
            delete root;
            return ret;
        }
    } else if (MatchExpression::NOR == root->matchType()) {
        // First clean up children.
        for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
            (*root->getChildVector())[i] = normalizeTree(root->getChild(i));
        }

        // NOR of one thing is NOT of the thing.
        if (1 == root->numChildren()) {
            // Detach the child and assume ownership.
            std::unique_ptr<MatchExpression> child(root->getChild(0));
            root->getChildVector()->clear();

            // Delete the root when this goes out of scope.
            std::unique_ptr<NorMatchExpression> ownedRoot(static_cast<NorMatchExpression*>(root));

            // Make a NOT to be the new root and transfer ownership of the child to it.
            auto newRoot = stdx::make_unique<NotMatchExpression>();
            newRoot->init(child.release()).transitional_ignore();

            return newRoot.release();
        }
    } else if (MatchExpression::NOT == root->matchType()) {
        // Normalize the rest of the tree hanging off this NOT node.
        NotMatchExpression* nme = static_cast<NotMatchExpression*>(root);
        MatchExpression* child = nme->releaseChild();
        // normalizeTree(...) takes ownership of 'child', and then
        // transfers ownership of its return value to 'nme'.
        nme->resetChild(normalizeTree(child));
    } else if (MatchExpression::ELEM_MATCH_OBJECT == root->matchType()) {
        // Normalize the rest of the tree hanging off this ELEM_MATCH_OBJECT node.
        ElemMatchObjectMatchExpression* emome = static_cast<ElemMatchObjectMatchExpression*>(root);
        auto child = emome->releaseChild();
        // normalizeTree(...) takes ownership of 'child', and then
        // transfers ownership of its return value to 'emome'.
        emome->resetChild(std::unique_ptr<MatchExpression>(normalizeTree(child.release())));
    } else if (MatchExpression::ELEM_MATCH_VALUE == root->matchType()) {
        // Just normalize our children.
        for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
            (*root->getChildVector())[i] = normalizeTree(root->getChild(i));
        }
    } else if (MatchExpression::MATCH_IN == root->matchType()) {
        std::unique_ptr<InMatchExpression> in(static_cast<InMatchExpression*>(root));

        // IN of 1 regex is the regex.
        if (in->getRegexes().size() == 1 && in->getEqualities().empty()) {
            RegexMatchExpression* childRe = in->getRegexes().begin()->get();
            invariant(!childRe->getTag());

            // Create a new RegexMatchExpression, because 'childRe' does not have a path.
            auto re = stdx::make_unique<RegexMatchExpression>();
            re->init(in->path(), childRe->getString(), childRe->getFlags()).transitional_ignore();
            if (in->getTag()) {
                re->setTag(in->getTag()->clone());
            }
            return normalizeTree(re.release());
        }

        // IN of 1 equality is the equality.
        if (in->getEqualities().size() == 1 && in->getRegexes().empty()) {
            auto eq = stdx::make_unique<EqualityMatchExpression>();
//.........这里部分代码省略.........