Allow MAX function as a CONCAT argument (improvement?)

[stphane]

I recently migrated our project from doctrine v2.5.6 to v2.6.1. and ran into an error saying:

Expected StateFieldPathExpression | string | InputParameter | FunctionsReturningStrings | AggregateExpression, got 'MAX'

… with the query being:

$QB = $this->_em->createQueryBuilder();
$QB ->addSelect("CONCAT(t2.dagId, MAX(t1.executionDate))")
    ->from(TaskInstance::class, 't1')
    ->join('t1.dag', 't2')
    ->addGroupBy('t2.dagId')
    ;


// Calling either getResults() or getSQL raises the error.
print_r($QB->getQuery()->getSQL());

After looking at Doctrine\ORM\Query\Parser::StringPrimary(), I ended up nesting MAX(…) call within a IF to fix the error:

$QB ->addSelect("CONCAT(t2.dagId, IF(1=1, MAX(t1.executionDate)))")

Is such a call rejection normal/intended or should this problem be addressed ?

[stof]

shouldn't MAX be an AggregateExpression ?

[stphane]

That's what I thought since it is an aggregate function. It feels surprising that such functions are not considered to be valid tokens in this context.

[NothingWeAre]

After encountering similar problem, and looking at code i've noticed that StringPrimary no longer processes aggregate functions, this change happened somwhere betwean 2.5.14 - 2.6.1
Old function looked like:

            case Lexer::T_CASE:
            case Lexer::T_COALESCE:
            case Lexer::T_NULLIF:
                return $this->CaseExpression();

            default:
                if ($this->isAggregateFunction($lookaheadType)) {
                    return $this->AggregateExpression();
                }
        }
        $this->syntaxError(
            'StateFieldPathExpression | string | InputParameter | FunctionsReturningStrings | AggregateExpression'
        );

while new one missing part responsible for accepting aggregate expressions:

            case Lexer::T_CASE:
            case Lexer::T_COALESCE:
            case Lexer::T_NULLIF:
                return $this->CaseExpression();
        }
        $this->syntaxError(
            'StateFieldPathExpression | string | InputParameter | FunctionsReturningStrings | AggregateExpression'
        );

I did not find any mentions of this in documentation (but I could have missed it), so i think this is regression.

[Majkl578]

This has been fixed in 2.6.2 via #7296.