Hydrating enumType as array gives *string* instead of Enum

[janedbal]

Bug Report

As discussed in original topic: #9588, but I see this as a bug as it behaves differently than any custom type. So migrating from enums used as custom types to this native form is impossible. Tested version: 2.11.2

Summary

$queryBuilder = $this->createQueryBuilder('f')
    ->select('f.id, f.suit')
    ->getQuery()
    ->getResult() // suit is string, not Suit enum
;

Current behavior

Column defined as enumType gets hydrated as string when array hydration occurs.

How to reproduce

Use entity as described and fetch from query builder as array.

Expected behavior

To be hydrated as enum.

[michnovka]

Ok, so given this some debugging and thought, this is a bit more difficult than it seemed. The reason why find()/findAll() methods hydrate the Enum type correctly is, that this is handled on the UoW level inside createEntity() through ClassMetadata::reflFields[]->setValue(). When using select of individual fields OR when using getArrayResult(), then hydration is done on individual fields and entity itself is not created.

[michnovka]

@derrabus I think that the issue here is that AbstractHydrator::hydrateAll() gets $resultSetMapping with scalarMappings set to string for suit column. I dont think I can access the enumType of the column from there. What would be the proper way? Can we leverage some other "mapping", like fieldMapping?

[michnovka]

So I see the $resultSetMapping is set inside SqlWalker here

orm/lib/Doctrine/ORM/Query/SqlWalker.php

Lines 1335 to 1352 in f4d5283

	$fieldMapping = $class->fieldMappings[$fieldName];
	$columnName = $this->quoteStrategy->getColumnName($fieldName, $class, $this->platform);
	$columnAlias = $this->getSQLColumnAlias($fieldMapping['columnName']);
	$col = $sqlTableAlias . '.' . $columnName;
	if (isset($fieldMapping['requireSQLConversion'])) {
	$type = Type::getType($fieldMapping['type']);
	$col = $type->convertToPHPValueSQL($col, $this->conn->getDatabasePlatform());
	}
	$sql .= $col . ' AS ' . $columnAlias;
	$this->scalarResultAliasMap[$resultAlias] = $columnAlias;
	if (! $hidden) {
	$this->rsm->addScalarResult($columnAlias, $resultAlias, $fieldMapping['type']);
	$this->scalarFields[$dqlAlias][$fieldName] = $columnAlias;
	}

Now the question is - do we introduce enumMappings? like

if(!empty($fieldMapping['enumType'])) {
    $this->rsm->addEnumMapping($columnAlias, $fieldMapping['enumType']);
}

then when walking $resultSetMapping->scalarMapping check for $resultSetMapping->enumMappings and if present cast to enum.

Or do you have another idea? Can we leverage something already present in the resultSetMapping?