Method isWritable

lib/vf_analyzers.cpp:1473–1511

    }

    Action isWritable(const Token* tok, Direction /*d*/) const override
    {
        if (astIsIterator(tok))
            return Action::None;
        if (!getValue(tok))
            return Action::None;
        if (!tok->valueType())
            return Action::None;
        if (!astIsContainer(tok))
            return Action::None;
        const Token* parent = tok->astParent();
        const Library::Container* container = getLibraryContainer(tok);

        if (container->stdStringLike && Token::simpleMatch(parent, "+=") && astIsLHS(tok) && parent->astOperand2()) {
            const Token* rhs = parent->astOperand2();
            if (rhs->tokType() == Token::eString)
                return Action::Read | Action::Write | Action::Incremental;
            const Library::Container* rhsContainer = getLibraryContainer(rhs);
            if (rhsContainer && rhsContainer->stdStringLike) {
                if (std::any_of(rhs->values().cbegin(), rhs->values().cend(), [&](const ValueFlow::Value &rhsval) {
                    return rhsval.isKnown() && rhsval.isContainerSizeValue();
                }))
                    return Action::Read | Action::Write | Action::Incremental;
            }
        } else if (astIsLHS(tok) && Token::Match(tok->astParent(), ". %name% (")) {
            const Library::Container::Action action = container->getAction(tok->astParent()->strAt(1));
            if (action == Library::Container::Action::PUSH || action == Library::Container::Action::POP || action == Library::Container::Action::APPEND) { // TODO: handle more actions?
                std::vector<const Token*> args = getArguments(tok->tokAt(3));
                bool isVariadic = false;
                if (const Library::Function* libFunc = settings.library.getFunction(tok->tokAt(2))) {
                    const auto& argChecks = libFunc->argumentChecks;
                    isVariadic = argChecks.find(-1) != argChecks.end() && argChecks.at(-1).variadic;
                }
                if (args.size() < 2 || action == Library::Container::Action::APPEND || isVariadic)
                    return Action::Read | Action::Write | Action::Incremental;
            }
        }
        return Action::None;
    }

    void writeValue(ValueFlow::Value* val, const Token* tok, Direction d) const override {
        if (!val)