$builder    ->add('choice1', ChoiceType::class, ['choices' => ['a' =>'a','b' =>'b','c' =>'c',        ],'multiple' =>true,    ])    ->add('choice2', ChoiceType::class, ['choices' => ['ab' => ['a' =>'a','b' =>'b',            ],'c' =>'c',        ],'multiple' =>true,    ]);

The code above will result in two identical selects:

The reason for this is hash generation inSymfony\Component\Form\ChoiceList\Factory\CachingFactoryDecorator::createListFromChoices() — it does not take array structure into account. Seethe comment and the code below it.

The comment says that the same choice list should be returned for the same collection of choices no matter the structure. This is wrong, becauseChoiceListInterface has a methodgetStructuredValues() and thus a list instance cannot identified by a hash which does not take structure into account.

I propose a simple change that fixes this and allows for similar choice fields with different groupings.

ping@HeahDude

Do not ignore the choice groups for caching

9007911

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Dec 26, 2018

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Dec 27, 2018

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👍 for me. Thanks!

Ping@stof, I remember discussing this edge case with you in Berlin two years ago (the workaround being the use ofgroup_by option instead of relying on the structured values), it seems it's worth to fix the issue to simplify things in master.

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nicolas-grekas added this to the3.4 milestone

Jan 3, 2019

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fabpot commentedJan 3, 2019

Thank you@vudaltsov.

fabpot merged commit9007911 intosymfony:3.4

Jan 3, 2019

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Jan 3, 2019

bug#29695[Form] Do not ignore the choice groups for caching (vudalt…

44bb346

…sov)This PR was merged into the 3.4 branch.Discussion----------[Form] Do not ignore the choice groups for caching| Q             | A| ------------- | ---| Branch?       | 3.4| Bug fix?      | yes| New feature?  | no| BC breaks?    | no| Deprecations? | no| Tests pass?   | yes| Fixed tickets | n/a| License       | MIT| Doc PR        | n/aWhile working on a different issue I suddenly came over a strange behaviour.```php$builder    ->add('choice1', ChoiceType::class, [        'choices' => [            'a' => 'a',            'b' => 'b',            'c' => 'c',        ],        'multiple' => true,    ])    ->add('choice2', ChoiceType::class, [        'choices' => [            'ab' => [                'a' => 'a',                'b' => 'b',            ],            'c' => 'c',        ],        'multiple' => true,    ]);```The code above will result in two identical selects:![image](https://user-images.githubusercontent.com/2552865/50459865-b3e36980-0980-11e9-8f3d-17f9cfa9a7f8.png)The reason for this is hash generation in `Symfony\Component\Form\ChoiceList\Factory\CachingFactoryDecorator::createListFromChoices()` — it does not take array structure into account. See [the comment and the code below it](https://github.com/symfony/symfony/blob/7f46dfb1c4ce5e45a5f1918ad6223a3bbdd52a0b/src/Symfony/Component/Form/ChoiceList/Factory/CachingFactoryDecorator.php#L116).The comment says that the same choice list should be returned for the same collection of choices no matter the structure. This is wrong, because `ChoiceListInterface` has a method `getStructuredValues()` and thus a list instance cannot identified by a hash which does not take structure into account.I propose a simple change that fixes this and allows for similar choice fields with different groupings.ping@HeahDudeCommits-------9007911 Do not ignore the choice groups for caching