[Fix] Mapping issues between a dropdown with multiple answers and it's form destination

CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 
+- Fix value mapping between a multiple dropdown field and it's destination in a form
 - Fix display width for rich text fields
 - Fix massive action update on CustomAssets
 - Fix mandatory fields on a Tab block not being enforced when updating an item.

inc/destinationfield.class.php

@@ -134,6 +134,13 @@ public function applyConfiguratedValueToInputUsingAnswers(
                 if ($field->fields['type'] == 'glpi_item') {
                     $input[sprintf('itemtype_%s', $field_name)] = $answer->getRawAnswer()['itemtype'];
                     $input[sprintf('items_id_%s', $field_name)] = $answer->getRawAnswer()['items_id'];
+                } elseif (str_starts_with((string) $field->fields['type'], 'dropdown') && $field->fields['multiple']) {
+                    // Multiple dropdowns are submitted as an array of ids
+                    $raw_ids = (array) ($answer->getRawAnswer()['items_id'] ?? []);
+                    $input[$field_name] = array_values(array_filter(
+                        array_map(intval(...), $raw_ids),
+                        fn(int $id) => $id > 0,
+                    ));
                 } elseif (str_starts_with((string) $field->fields['type'], 'dropdown')) {
                     $raw_id = (int) ($answer->getRawAnswer()['items_id'] ?? 0);
                     $input[$field_name] = ($raw_id > 0) ? $raw_id : null;

inc/questiontype.class.php

@@ -242,6 +242,10 @@ public function formatRawAnswer(mixed $answer, Question $question): string
                 return '';
             }
 
+            if (is_array($answer) && array_key_exists('items_id', $answer)) {
+                $answer = $answer['items_id'];
+            }
+
             if (!is_array($answer)) {
                 $answer = [$answer];
             }

tests/Units/FieldDestinationFieldTest.php

@@ -46,6 +46,7 @@
 use Override;
 use PluginFieldsContainer;
 use PluginFieldsDestinationField;
+use PluginFieldsDropdown;
 use PluginFieldsQuestionType;
 use Problem;
 use Ticket;
@@ -120,12 +121,32 @@ private function initFieldTest(): void
         ]);
         $this->fields[] = $this->createField([
             'label'                                     => 'Location Field',
-            'type'                                      => 'dropdown-Location',
+            'type'                                      => 'dropdown-' . Location::class,
             PluginFieldsContainer::getForeignKeyField() => $this->blocks[Ticket::class]->getID(),
             'ranking'                                   => 3,
             'is_active'                                 => 1,
             'is_readonly'                               => 0,
         ]);
+        $this->fields[] = $this->createField([
+            'label'                                     => 'Multiple dropdown',
+            'type'                                      => 'dropdown',
+            'multiple'                                  => 1,
+            'default_value'                             => [],
+            PluginFieldsContainer::getForeignKeyField() => $this->blocks[Ticket::class]->getID(),
+            'ranking'                                   => 4,
+            'is_active'                                 => 1,
+            'is_readonly'                               => 0,
+        ], ['default_value']);
+        $this->fields[] = $this->createField([
+            'label'                                     => 'Multiple locations',
+            'type'                                      => 'dropdown-' . Location::class,
+            'multiple'                                  => 1,
+            'default_value'                             => [],
+            PluginFieldsContainer::getForeignKeyField() => $this->blocks[Ticket::class]->getID(),
+            'ranking'                                   => 5,
+            'is_active'                                 => 1,
+            'is_readonly'                               => 0,
+        ], ['default_value']);
     }
 
     public function setUp(): void
@@ -254,6 +275,68 @@ public function testDestinationWithLocationAdditonalFields(): void
         $location->delete($location->fields, true);
     }
 
+    public function testDestinationWithMultipleDropdownAdditionalFields(): void
+    {
+        $this->login();
+
+        $dropdown_field  = $this->fields[5];
+        $locations_field = $this->fields[6];
+
+        $form = $this->createForm(
+            (new FormBuilder())
+                ->addQuestion("Multiple dropdown", PluginFieldsQuestionType::class, extra_data: json_encode([
+                    'block_id' => $this->blocks[Ticket::class]->getID(),
+                    'field_id' => $dropdown_field->getID(),
+                ]))
+                ->addQuestion("Multiple locations", PluginFieldsQuestionType::class, extra_data: json_encode([
+                    'block_id' => $this->blocks[Ticket::class]->getID(),
+                    'field_id' => $locations_field->getID(),
+                ])),
+        );
+
+        $dropdown_class = PluginFieldsDropdown::getClassname($dropdown_field->fields['name']);
+        $value1 = $this->createItem($dropdown_class, ['name' => 'Value 1', 'entities_id' => 0]);
+        $value2 = $this->createItem($dropdown_class, ['name' => 'Value 2', 'entities_id' => 0]);
+
+        $location1 = $this->createItem(Location::class, [
+            'name'        => 'Location 1',
+            'entities_id' => $this->getTestRootEntity(true),
+        ]);
+        $location2 = $this->createItem(Location::class, [
+            'name'        => 'Location 2',
+            'entities_id' => $this->getTestRootEntity(true),
+        ]);
+
+        try {
+            $this->sendFormAndAssertITILObjectAdditionalFields(
+                form: $form,
+                config: new SimpleValueConfig(1),
+                answers: [
+                    // Multiple dropdowns are submitted as an array of ids
+                    "Multiple dropdown" => [
+                        'itemtype' => $dropdown_class,
+                        'items_id' => [(string) $value1->getID(), (string) $value2->getID()],
+                    ],
+                    "Multiple locations" => [
+                        'itemtype' => Location::class,
+                        'items_id' => [(string) $location1->getID(), (string) $location2->getID()],
+                    ],
+                ],
+                expected_field_values: [
+                    Ticket::class => [
+                        'plugin_fields_' . $dropdown_field->fields['name'] . 'dropdowns_id' => json_encode([$value1->getID(), $value2->getID()]),
+                        $locations_field->fields['name'] => json_encode([$location1->getID(), $location2->getID()]),
+                    ],
+                ],
+            );
+        } finally {
+            // delete created items for another run
+            foreach ([$value1, $value2, $location1, $location2] as $item) {
+                $item->delete($item->fields, true);
+            }
+        }
+    }
+
     #[Override]
     public static function provideConvertFieldConfigFromFormCreator(): iterable
     {

tests/Units/FieldQuestionTypeTest.php

@@ -38,10 +38,12 @@
 use Glpi\Form\Condition\Type;
 use Glpi\Form\Condition\ValueOperator;
 use Glpi\Form\Condition\VisibilityStrategy;
+use Glpi\Form\Question;
 use Glpi\Form\QuestionType\QuestionTypeShortText;
 use Glpi\Form\QuestionType\QuestionTypesManager;
 use Glpi\Tests\FormBuilder;
 use GlpiPlugin\Field\Tests\QuestionTypeTestCase;
+use Location;
 use LogicException;
 use PluginFieldsContainer;
 use PluginFieldsDropdown;
@@ -188,6 +190,58 @@ public function testFieldsQuestionSubmitEmptyDropdown(): void
         ]);
     }
 
+    public function testFormatRawAnswerForMultipleGlpiItemDropdown(): void
+    {
+        $this->login();
+
+        // Arrange: create a multiple "dropdown-Location" field
+        $this->fields['locations'] = $this->createField([
+            'label'                                     => 'Locations',
+            'type'                                      => 'dropdown-' . Location::class,
+            'multiple'                                  => 1,
+            'default_value'                             => [],
+            PluginFieldsContainer::getForeignKeyField() => $this->block->getID(),
+            'ranking'                                   => 2,
+            'is_active'                                 => 1,
+        ], ['default_value']);
+
+        $location1 = $this->createItem(Location::class, [
+            'name'        => __FUNCTION__ . ' 1',
+            'entities_id' => $this->getTestRootEntity(true),
+        ]);
+        $location2 = $this->createItem(Location::class, [
+            'name'        => __FUNCTION__ . ' 2',
+            'entities_id' => $this->getTestRootEntity(true),
+        ]);
+
+        $builder = new FormBuilder("My form");
+        $builder->addQuestion(
+            "Locations question",
+            PluginFieldsQuestionType::class,
+            extra_data: json_encode($this->getFieldExtraDataConfig('locations')),
+        );
+        $form = $this->createForm($builder);
+        $question = Question::getById($this->getQuestionId($form, "Locations question"));
+
+        try {
+            // Act: format the answer as submitted by the end user template
+            $formatted = (new PluginFieldsQuestionType())->formatRawAnswer([
+                'itemtype' => Location::class,
+                'items_id' => [(string) $location1->getID(), (string) $location2->getID()],
+            ], $question);
+
+            // Assert: both location names are displayed
+            $this->assertEquals(
+                $location1->fields['name'] . ', ' . $location2->fields['name'],
+                $formatted,
+            );
+        } finally {
+            // delete locations for another run
+            $location1->delete($location1->fields, true);
+            $location2->delete($location2->fields, true);
+        }
+    }
+
     public function testFieldDeletionWhenUsedInForm(): void
     {
         $this->login();