Function singleAssignInScope

lib/checkstl.cpp:2652–2684

enum class LoopType : std::uint8_t { OTHER, RANGE, ITERATOR, INDEX };

static const Token *singleAssignInScope(const Token *start, nonneg int varid, bool &input, bool &hasBreak, LoopType loopType, const Settings& settings)
{
    const Token *endStatement = singleStatement(start);
    if (!endStatement)
        return nullptr;
    if (!Token::Match(start->next(), "%var% %assign%"))
        return nullptr;
    const Token *assignTok = start->tokAt(2);
    if (isVariableChanged(assignTok->next(), endStatement, assignTok->astOperand1()->varId(), /*globalvar*/ false, settings))
        return nullptr;
    if (isVariableChanged(assignTok->next(), endStatement, varid, /*globalvar*/ false, settings))
        return nullptr;
    input = Token::findmatch(assignTok->next(), "%varid%", endStatement, varid) || !Token::Match(start->next(), "%var% =");
    hasBreak = Token::simpleMatch(endStatement->previous(), "break");

    if (loopType == LoopType::INDEX) { // check for container access
        nonneg int containerId{};
        for (const Token* tok = assignTok->next(); tok != endStatement; tok = tok->next()) {
            if (tok->varId() == varid) {
                if (!Token::simpleMatch(tok->astParent(), "["))
                    return nullptr;
                const Token* contTok = tok->astParent()->astOperand1();
                if (!contTok->valueType() || !contTok->valueType()->container || contTok->varId() == 0)
                    return nullptr;
                if (containerId > 0 && containerId != contTok->varId()) // allow only one container
                    return nullptr;
                containerId = contTok->varId();
            }
        }
        return containerId > 0 ? assignTok : nullptr;
    }
    return assignTok;
}

static const Token *singleMemberCallInScope(const Token *start, nonneg int varid, bool &input, const Settings& settings)
{