bug #17163 [Form] fix Catchable Fatal Error if choices is not an array (Gladhon, nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
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[Form] fix Catchable Fatal Error if choices is not an array

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        |

Since 2.7.8 I got a BC-Break Error

Catchable Fatal Error: Argument 1 passed to Symfony\Component\Form\Extension\Core\Type\ChoiceType::normalizeLegacyChoices() must be of the type array, null given

normalizeLegacyChoices work only with array, so if choices not an array, just don't try to normlize.

Commits
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f3c2a9b [Form] fix Catchable Fatal Error if choices is not an array

Author: nicolas-grekas

Extension/Core/Type/ChoiceType.php

@@ -263,9 +263,11 @@ public function configureOptions(OptionsResolver $resolver)
                 return $choices;
             }
 
-            ChoiceType::normalizeLegacyChoices($choices, $choiceLabels);
+            if (null === $choices) {
+                return;
+            }
 
-            return $choices;
+            return ChoiceType::normalizeLegacyChoices($choices, $choiceLabels);
         };
 
         // BC closure, to be removed in 3.0
@@ -504,26 +506,30 @@ private function createChoiceListView(ChoiceListInterface $choiceList, array $op
      * are lost. Store them in a utility array that is used from the
      * "choice_label" closure by default.
      *
-     * @param array  $choices      The choice labels indexed by choices.
-     *                             Labels are replaced by generated keys.
-     * @param object $choiceLabels The object that receives the choice labels
-     *                             indexed by generated keys.
-     * @param int    $nextKey      The next generated key.
+     * @param array|\Traversable $choices      The choice labels indexed by choices.
+     * @param object             $choiceLabels The object that receives the choice labels
+     *                                         indexed by generated keys.
+     * @param int                $nextKey      The next generated key.
+     *
+     * @return array The choices in a normalized array with labels replaced by generated keys.
      *
      * @internal Public only to be accessible from closures on PHP 5.3. Don't
      *           use this method as it may be removed without notice and will be in 3.0.
      */
-    public static function normalizeLegacyChoices(array &$choices, $choiceLabels, &$nextKey = 0)
+    public static function normalizeLegacyChoices($choices, $choiceLabels, &$nextKey = 0)
     {
+        $normalizedChoices = array();
+
         foreach ($choices as $choice => $choiceLabel) {
-            if (is_array($choiceLabel)) {
-                $choiceLabel = ''; // Dereference $choices[$choice]
-                self::normalizeLegacyChoices($choices[$choice], $choiceLabels, $nextKey);
+            if (is_array($choiceLabel) || $choiceLabel instanceof \Traversable) {
+                $normalizedChoices[$choice] = self::normalizeLegacyChoices($choiceLabel, $choiceLabels, $nextKey);
                 continue;
             }
 
             $choiceLabels->labels[$nextKey] = $choiceLabel;
-            $choices[$choice] = $nextKey++;
+            $normalizedChoices[$choice] = $nextKey++;
         }
+
+        return $normalizedChoices;
     }
 }

Tests/Extension/Core/Type/ChoiceTypeTest.php

@@ -487,6 +487,21 @@ public function testSubmitSingleNonExpandedObjectChoices()
         $this->assertTrue($form->isSynchronized());
     }
 
+    /**
+     * @group legacy
+     */
+    public function testLegacyNullChoices()
+    {
+        $form = $this->factory->create('choice', null, array(
+            'multiple' => false,
+            'expanded' => false,
+            'choices' => null,
+        ));
+        $this->assertNull($form->getConfig()->getOption('choices'));
+        $this->assertFalse($form->getConfig()->getOption('multiple'));
+        $this->assertFalse($form->getConfig()->getOption('expanded'));
+    }
+
     /**
      * @group legacy
      */