minor #17351 [Form] Improve ChoiceType CS (HeahDude)

This PR was merged into the 4.4 branch.

Discussion
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[Form] Improve `ChoiceType` CS

Commits
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5e9482b [Form] Improve `ChoiceType` CS

Author: javiereguiluz

reference/forms/types/choice.rst

@@ -72,21 +72,21 @@ method::
         // a callback to return the label for a given choice
         // if a placeholder is used, its empty value (null) may be passed but
         // its label is defined by its own "placeholder" option
-        'choice_label' => function(?Category $category) {
+        'choice_label' => function (?Category $category) {
             return $category ? strtoupper($category->getName()) : '';
         },
         // returns the html attributes for each option input (may be radio/checkbox)
-        'choice_attr' => function(?Category $category) {
+        'choice_attr' => function (?Category $category) {
             return $category ? ['class' => 'category_'.strtolower($category->getName())] : [];
         },
         // every option can use a string property path or any callable that get
         // passed each choice as argument, but it may not be needed
-        'group_by' => function() {
+        'group_by' => function () {
             // randomly assign things into 2 groups
             return rand(0, 1) == 1 ? 'Group A' : 'Group B';
         },
         // a callback to return whether a category is preferred
-        'preferred_choices' => function(?Category $category) {
+        'preferred_choices' => function (?Category $category) {
             return $category && 100 < $category->getArticleCounts();
         },
     ]);
@@ -190,7 +190,7 @@ if you want to take advantage of lazy loading::
     // ...
 
     $builder->add('constants', ChoiceType::class, [
-        'choice_loader' => new CallbackChoiceLoader(function() {
+        'choice_loader' => new CallbackChoiceLoader(function () {
             return StaticClass::getConstants();
         }),
     ]);

reference/forms/types/options/choice_attr.rst.inc

@@ -33,7 +33,7 @@ If an array, the keys of the ``choices`` array must be used as keys::
             'No' => false,
             'Maybe' => null,
         ],
-        'choice_attr' => function($choice, $key, $value) {
+        'choice_attr' => function ($choice, $key, $value) {
             // adds a class like attending_yes, attending_no, etc
             return ['class' => 'attending_'.strtolower($key)];
         },